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1.
Chem Soc Rev ; 51(6): 2313-2382, 2022 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-35244107

RESUMO

Visible-light photoredox catalysis has been regarded as an extremely powerful tool in organic chemistry, bringing the spotlight back to radical processes. The versatility of photocatalyzed reactions has already been demonstrated to be effective in providing alternative routes for cross-coupling as well as multicomponent reactions. The photocatalyst allows the generation of high-energy intermediates through light irradiation rather than using highly reactive reagents or harsh reaction conditions. In a similar vein, organic electrochemistry has experienced a fruitful renaissance as a tool for generating reactive intermediates without the need for any catalyst. Such milder approaches pose the basis toward higher selectivity and broader applicability. In photocatalyzed and electrochemical multicomponent reactions, the generation of the radical species acts as a starter of the cascade of events. This allows for diverse reactivity and the use of reagents is usually not covered by classical methods. Owing to the availability of cheaper and more standardized photo- and electrochemical reactors, as well as easily scalable flow-setups, it is not surprising that these two fields have become areas of increased research interest. Keeping these in view, this review is aimed at providing an overview of the synthetic approaches in the design of MCRs involving photoredox catalysis and/or electrochemical activation as a crucial step with particular focus on the choice of the difunctionalized reagent.

2.
Chimia (Aarau) ; 77(5): 327-338, 2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38047829

RESUMO

The popularity of microflow chemistry has skyrocketed in the last 20 years, more and more chemists are switching from macro-batch reactors to miniaturized flow devices. As a result, microfluidics is paving its way into the future by consolidating its position in organic chemistry not only as a trend but as a new, effective, and sustainable way of conducting chemistry, that clearly will continue to grow and evolve. This perspective highlights the most relevant examples of innovative enhancing technologies applied to microflow reactors aimed to improve and intensify chemical processes. The extensive applicability of microflow chemistry is further illustrated by briefly discussing examples of complex integrated microsystems and scale-up technologies, demonstrating ultimately that microflow chemistry has the potential to become the ideal technology for the future.

3.
Clin Exp Dermatol ; 46(6): 1075-1078, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33577095

RESUMO

During the SARS-CoV-2 (COVID-19) pandemic, an unusual outbreak of yellow-brown pigmentation on the skin of children was reported. Because of the restrictions on movement promulgated during the lockdown, most consultancies were performed using teledermatology. Data concerning personal care products and application of topical substances were collected, which revealed use of the same brand of wipes for all patients. A liquid chromatography-mass spectrometry analysis was performed to compare the components of the wipes before and after the observation of the pigmentation, in order to detect the responsible substance. This analysis revealed a level about 10-fold higher than normal of ascorbic acid and its oxidation products (dehydroascorbic acid and L-threonic acid) in the wipes associated with the pigmentation. These 'colouring wipes' represent a peculiar but harmless phenomenon that highlights the importance of careful questioning about personal care products used by patients.


Assuntos
Ácido Ascórbico/efeitos adversos , COVID-19/epidemiologia , Pandemias , Quarentena , Pigmentação da Pele/efeitos dos fármacos , Pele/patologia , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Espectrometria de Massas , Vitaminas/efeitos adversos
4.
J Eur Acad Dermatol Venereol ; 34(11): 2630-2635, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32533899

RESUMO

BACKGROUND: Over the last months, during the COVID-19 pandemic, a growing number of chilblain-like lesions were reported mainly in children and rarely in young adults. The relationship with SARS-CoV-2 infection was postulated, often without any laboratory, instrumental or clinical confirmation. The disclosure of information about chilblain-like lesions as a COVID-19 manifestation in social media has created concern in children's families and paediatricians. OBJECTIVES: To verify whether the chilblain-like lesions were caused by SARS-CoV-2 infection. METHODS: Prospective study on a case series including children who presented with acral lesions at the Pediatric Dermatology Outpatient and Pediatric Emergency Unit of the University of Bologna, from 1 April to 30 April 2020. We reported demographical, laboratory and clinical features, history of close contact with COVID-19 patients, presence of similar skin lesions in other family members, precipitating and risk factors for chilblain onset. RESULTS: We evaluated eight patients (five females, three males) aged between 11 and 15 years. We excluded acute or previous SARS-CoV-2 infection with RT-PCR nasopharyngeal swab, serum antibody levels using chemiluminescent immunoassays. Other acute infections causing purpuric lesions at the extremities were negative in all patients. Skin lesion biopsy for histological and immunohistochemical evaluation was made in two cases and was consistent with chilblain. PCR assay on skin lesion biopsy for parvovirus B19, Mycoplasma pneumoniae and SARS-CoV-2 was performed in a patient and resulted negative. We identified common precipitating and risk factors: physical (cold and wet extremities, low BMI), cold and wet indoor and outdoor environment, behaviours, habits and lifestyle. We therefore reached a diagnosis of primary chilblains. CONCLUSIONS: During the COVID-19 pandemic, a 'cluster' of primary chilblains developed in predisposed subjects, mainly teenagers, due to cold exposure in the lockdown period. Laboratory findings support our hypothesis, although it is also possible that an unknown infectious trigger may have contributed to the pathogenesis.


Assuntos
COVID-19/complicações , Pérnio/etiologia , Adolescente , Biópsia , COVID-19/epidemiologia , Teste para COVID-19 , Pérnio/epidemiologia , Criança , Feminino , Humanos , Itália/epidemiologia , Estilo de Vida , Masculino , Pandemias , Estudos Prospectivos , Quarentena , SARS-CoV-2
14.
J Craniofac Surg ; 25(2): 397-9, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24561366

RESUMO

AIM: The objective of this study was to evaluate the incidence of plate-related complications after vascularized bony reconstruction of the mandible, comparing the plate type used. PATIENTS AND METHODS: Between 2004 and December 2012, a total of 41 free osteocutaneous fibula flaps have been used in an equal number of patients for reconstruction of the mandible, at the Division of Maxillofacial surgery, San Giovanni Battista Hospital, University of Turin. Malignant pathology was the most common indication for segmental mandibulectomy.Patient outcomes were retrospectively evaluated with special attention to plate complications such as plate fracture, exposure, infection, and bony nonunion.The types of reconstruction plates used were mandible plates 2.0, locking plates 2.0, miniplates (<2.0), and locking 2.4 plates. RESULTS: Mandible plates 2.0 were used in 14 patients, locking plates 2.0 in 12 patients, and locking 2.4 plates in 4 patients. The most commonly used plates were miniplates, which were used in 86 patients.A total of 5 plate complications occurred after 41 procedures in an equal number of patients.Two complications occurred in patients receiving 2.0 mandible plates (2/14). One complication occurred in patients receiving 2.0 locking plates (1/12). Two complications occurred in patients receiving miniplates (2/86). CONCLUSIONS: In our experience, miniplates are not associated to a high rate of complications comparing to other plates. The advantage of these plates and the low rate of complications make them our first choice for mandibular reconstructions.


Assuntos
Placas Ósseas/efeitos adversos , Transplante Ósseo/métodos , Fíbula/transplante , Retalhos de Tecido Biológico , Reconstrução Mandibular/métodos , Complicações Pós-Operatórias , Adulto , Idoso , Feminino , Humanos , Masculino , Traumatismos Mandibulares/cirurgia , Neoplasias Mandibulares/cirurgia , Osteotomia Mandibular/métodos , Pessoa de Meia-Idade , Estudos Retrospectivos
16.
Front Microbiol ; 13: 999839, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36406439

RESUMO

Dental caries and periodontal diseases remain a challenge for oral health, especially given the lack of effective and safe treatment options that are currently available. Against the backdrop of an ongoing antimicrobial resistance crisis, a renewed interest in traditional medicinal plants as a potential source of new bioactive compounds has surfaced. In this context, we systematically screened the antimicrobial and anti-biofilm activities of both ethanolic and aqueous extracts of nine Algerian medicinal plants (Artemisia herba alba, Centaurium erythraea, Juglans regia, Laurus nobilis, Matricaria recutita, Mentha pulegium, Mentha piperita, Origanum vulgare and Taraxacum officinale). To evaluate the activity spectrum of the extracts, the screening was carried out against an extensive collection of Streptococcus, Enterococcus and Lacticaseibacillus isolates recovered from dental plaques of Algerian patients. Broad-spectrum antimicrobial and anti-biofilm properties were observed, especially among ethanolic extracts, which marks them as a promising source for bioactive compounds to control oral biofilms. The ethanolic extract of O. vulgare, which showed the most promising effects in the initial screening, was further characterized. We first verified the biocompatibility of this extract using human oral keratinocytes and selected a range of non-cytotoxic concentrations (0.195-0.781 mg/ml) to further validate its anti-biofilm and anti-virulence potential. At these concentrations, the extract not only prevented biofilm formation (10.04 ± 0.75-87.91 ± 9.08% of reduction) of most dental plaque isolates on a polystyrene surface, but also significantly reduced their adherence to hydroxyapatite (34.58 ± 9.09-62.77 ± 0.95%). Moreover, the extract showed curative potential against mature biofilms grown under conditions mimicking the oral niche. In addition to its anti-biofilm properties, we observed an inhibition of glucosyltransferase activity, a reduction in acidogenesis and a downregulation in the expression of multiple virulence-associated genes for extract-treated samples. Since anti-virulence properties are more robust to the development of resistance, they provide an attractive complementation to the antimicrobial activities of the extract. Thymol was identified as an important active compound of the extract using GC-MS analysis, but synergy with other compounds was also detected, suggesting a potential advantage of using the whole extract over purified thymol. Further research into the bioactive compounds of the O. vulgare ethanolic extract could yield novel products to fight dental caries.

17.
Artigo em Inglês | MEDLINE | ID: mdl-10102587

RESUMO

OBJECTIVE: The purpose of this study was to determine the anesthetic efficacy and heart rate effects of a supplemental intraosseous injection of 2% mepivacaine with 1:20,000 levonordefrin. STUDY DESIGN: Through use of a repeated-measures design, 40 subjects randomly received 3 combinations of injections at 3 separate appointments. The combinations were as follows: inferior alveolar nerve (IAN) block (with 3% mepivacaine) + intraosseous injection of 1.8 mL of 2% mepivacaine with 1:20,000 levonordefrin; IAN block + intraosseous injection of 1.8 mL of 2% lidocaine with 1:100,000 epinephrine (positive control); IAN block + mock intraosseous injection (negative control). Each first molar, second molar, and second premolar was blindly tested with a pulp tester at 2-minute cycles for 60 minutes after injection. Anesthesia was considered successful when 2 consecutive readings of 80 were obtained. Heart rate (pulse rate) was measured with a pulse oximeter. RESULTS: One hundred percent of the subjects had lip numbness with the IAN block + intraosseous mock technique and IAN block + intraosseous techniques. The anesthetic success rates for IAN block + mock intraosseous injection, IAN block + intraosseous lidocaine, and IAN block + intraosseous mepivacaine, respectively, were as follows: 80%, 100%, and 100% for the first molar; 90%, 100%, and 100% for the second molar; 77%, 97%, and 97% for the second premolar. For the first molar and second premolar, the differences were significant (P< .05) when the intraosseous mepivacaine and lidocaine techniques were compared with the IAN block + mock intraosseous injection. There were no significant differences between the intraosseous mepivacaine and lidocaine techniques. Eighty percent of the subjects had a mean increase in heart rate of 23-24 beats per minute with the intraosseous injection of the mepivacaine and lidocaine solutions; there were no significant differences between results with the 2 solutions. CONCLUSIONS: We concluded that intraosseous injection of 1.8 mL of 2% lidocaine with 1:100,000 epinephrine or 2% mepivacaine with 1:20,000 levonordefrin, used to supplement an IAN block, significantly increased anesthetic success in first molars and second premolars. The 2 solutions were equivalent with regard to intraosseous anesthetic success rate, failure rate, and heart rate increase after IAN block.


Assuntos
Anestesia Dentária/métodos , Frequência Cardíaca/efeitos dos fármacos , Mepivacaína/farmacologia , Bloqueio Nervoso/métodos , Nordefrin/farmacologia , Adulto , Feminino , Humanos , Injeções/métodos , Masculino , Nervo Mandibular , Mepivacaína/administração & dosagem , Nordefrin/administração & dosagem , Avaliação de Resultados em Cuidados de Saúde , Medição da Dor
18.
Chir Ital ; 30(3): 286-93, 1978 Jun.
Artigo em Italiano | MEDLINE | ID: mdl-688552

RESUMO

A very rare case of carcinoid of the testicle combined with teratoma is illustrated. In fact the literature of the last twenty years reports only eleven cases of carcinoid of the testicle, of which only four combined with teratoma. It is stressed that it is possible that these neoplasias arise on already existing teratomas which may be very small and hence not always evidenced.


Assuntos
Tumor Carcinoide , Neoplasias Testiculares , Adulto , Tumor Carcinoide/complicações , Humanos , Masculino , Neoplasias Primárias Múltiplas , Teratoma/complicações
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