Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 17 de 17
Filtrar
1.
Bioorg Chem ; 81: 642-648, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30253337

RESUMO

Several new molecules with different thio-scaffolds were designed, synthesised, and evaluated biologically as inhibitors of Carbonic Anhydrases (CAIs). The structure-activity relationship analysis identified thioether derivatives, here reported, as a potent and selective CAIs against hCA II and hCA IX. High resolution X-ray structure of inhibitor bound hCA II revealed extensive interactions with the hydrophobic pocket of active site and provided molecular insight into the binding properties of these new inhibitors.


Assuntos
Anidrase Carbônica II/antagonistas & inibidores , Anidrase Carbônica IX/antagonistas & inibidores , Inibidores da Anidrase Carbônica/química , Inibidores da Anidrase Carbônica/farmacologia , Sulfonamidas/química , Sulfonamidas/farmacologia , Anidrase Carbônica II/química , Anidrase Carbônica II/metabolismo , Anidrase Carbônica IX/química , Anidrase Carbônica IX/metabolismo , Inibidores da Anidrase Carbônica/síntese química , Domínio Catalítico/efeitos dos fármacos , Cristalografia por Raios X , Humanos , Simulação de Acoplamento Molecular , Compostos de Sulfidrila/síntese química , Compostos de Sulfidrila/química , Compostos de Sulfidrila/farmacologia , Sulfonamidas/síntese química
2.
J Xenobiot ; 13(1): 75-89, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36810432

RESUMO

BACKGROUND: The use of herbs to treat illnesses was common in all historical eras. Our aim was to describe the phytotherapeutic substances that cancer patients use most commonly, and to determine whether their use can increase side effects. METHODS: This was a retrospective and descriptive study conducted among older adults actively undergoing chemotherapy, admitted at the Oncology DH Unit (COES) of the Molinette Hospital AOU Città della Salute e della Scienza in Turin (Italy). Data collection was conducted through the distribution of self-compiled and closed-ended questionnaires during chemotherapy treatment. RESULTS: A total of 281 patients were enrolled. Evaluating retching and sage consumption was statistically significant in multivariate analysis. The only risk factor for dysgeusia was chamomile consumption. Ginger, pomegranate, and vinegar use were retained as mucositis predictors. CONCLUSIONS: Phytotherapeutic use needs more attention in order to decrease the risks of side effects, toxicity, and ineffective treatment. The conscious administration of these substances should be promoted for safe use and to provide the reported benefits.

3.
Cancers (Basel) ; 15(19)2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37835377

RESUMO

Background. R0 minor parenchyma-sparing hepatectomy (PSH) is feasible for colorectal liver metastases (CRLM) in contact with hepatic veins (HV) at hepatocaval confluence since HV can be reconstructed, but in the case of contact with the first-order glissonean pedicle (GP), major hepatectomy is mandatory. To pursue an R0 parenchyma-sparing policy, we proposed vessel-guided mesohepatectomy for liver partition (MLP) and eventually combination with liver augmentation techniques for staged major PSH. Methods. We analyzed 15 consecutive vessel-guided MLPs for CRLM at the hepatocaval confluence. Patients had a median of 11 (range: 0-67) lesions with a median diameter of 3.5 cm (range: 0.0-8.0), bilateral in 73% of cases. Results. Grade IIIb or more complications occurred in 13%, median hospital stay was 14 (range: 6-62) days, 90-day mortality was 0%. After a median follow-up of 17.5 months, 1-year OS and RFS were 92% and 62%. In nine (64%) patients, MLP was combined with portal vein embolization (PVE) or ALPPS to perform staged R0 major PSH. Future liver remnant (FLR) volume increased from a median of 15% (range: 7-20%) up to 41% (range: 37-69%). Super-selective PVE was performed in three (33%) patients and enhanced ALPPS (e-ALPPS) in six (66%). In two e-ALPPS an intermediate stage of deportalized liver PSH was necessary to achieve adequate FLR volume. Conclusions. Vessel-guided MLP may transform the liver in a paired organ. In selected cases of multiple bilobar CRLM, to guarantee oncological radicality (R0), major PSH is feasible combining advanced surgical parenchyma sparing with liver augmentation techniques when FLR volume is insufficient.

4.
J Pediatr Gastroenterol Nutr ; 54(5): 624-9, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22197939

RESUMO

OBJECTIVES: The extent to which variation in taste perception influences food preferences is, to date, controversial. Bitterness in food triggers an innate aversion that is responsible for dietary restriction in children. We investigated the association among genetic variations in bitter receptor TAS2R38 and food choices in healthy children in the Mediterranean area, to develop appropriate tools to evaluate the relation among genetic predisposition, dietary habits, and feeding disorders. The aims of the study were to get a first baseline picture of taste sensitivity in healthy adults and their children and to explore taste sensitivity in a preliminary sample of obese children and in samples affected by functional gastrointestinal diseases. METHODS: Individuals (98 children, 87 parents, 120 adults) were recruited from the general population in southern Italy. Bitterness sensitivity was assessed by means of a suprathreshold method with 6-propyl-2-thiouracil. Genomic DNA from saliva was used to genotype individuals for 3 polymorphisms of TAS2R38 receptor, A49P, A262 V, and V296I. Food intake was assessed by a food frequency questionnaire. RESULTS: Children's taste sensation differed from that of adults: we observed a higher frequency of supertasters among children even in the mother-child dyads with the same diplotypes. Among adults, supertaster status was related with proline-alanine-valine (taster allele) homozygous haplotype, whereas supertaster children were mainly heterozygous. Regarding the food choices, we found that a higher percentage of taster children avoided bitter vegetables or greens altogether compared with taster adults. Taster status was also associated with body mass index in boys. CONCLUSIONS: Greater sensitivity to 6-propyl-2-thiouracil predicts lower preferences for vegetables in children, showing an appreciable effect of the genetic predisposition on food choices. None of the obese boys was a supertaster.


Assuntos
Comportamento de Escolha , Comportamento Alimentar , Preferências Alimentares , Percepção Gustatória/genética , Adolescente , Adulto , Índice de Massa Corporal , Criança , Pré-Escolar , Feminino , Variação Genética , Genótipo , Humanos , Itália , Masculino , Fenótipo , Propiltiouracila/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Inquéritos e Questionários , Paladar/genética , Paladar/fisiologia , Limiar Gustativo , Verduras , Adulto Jovem
5.
Chemistry ; 17(38): 10682-9, 2011 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-21826753

RESUMO

The xenon-difluoronitrenium ion F(2)N-Xe(+) , a novel xenon-nitrogen species, was obtained in the gas phase by the nucleophilic displacement of HF from protonated NF(3) by Xe. According to Møller-Plesset (MP2) and CCSD(T) theoretical calculations, the enthalpy and Gibbs energy changes (ΔH and ΔG) of this process are predicted to be -3 kcal mol(-1) . The conceivable alternative formation of the inserted isomers FN-XeF(+) is instead endothermic by approximately 40-60 kcal mol(-1) and is not attainable under the employed ion-trap mass spectrometric conditions. F(2)N-Xe(+) is theoretically characterized as a weak electrostatic complex between NF(2)(+) and Xe, with a Xe-N bond length of 2.4-2.5 Å, and a dissociation enthalpy and free energy into its constituting fragments of 15 and 8 kcal mol(-1), respectively. F(2)N-Xe(+) is more fragile than the xenon-nitrenium ions (FO(2)S)(2)NXe(+), F(5)SN(H)Xe(+), and F(5)TeN(H)Xe(+) observed in the condensed phase, but it is still stable enough to be observed in the gas phase. Other otherwise elusive xenon-nitrogen species could be obtained under these experimental conditions.


Assuntos
Gases/química , Nitrogênio/química , Xenônio/química , Íons/química , Modelos Teóricos , Termodinâmica
6.
Eur J Mass Spectrom (Chichester) ; 17(3): 197-206, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21828411

RESUMO

The positive ion chemistry occurring in SiH(4)/GeF(4) gaseous mixtures was investigated by ion trap mass spectrometry and ab initio theoretical calculations. The GeF(3)(+) cation, the only fragment obtained from ionized GeF(4), was unreactive towards SiH(4). All the primary ions SiH(n)(+) (n = 0-3) react instead with GeF(4) so to form SiF(+) or SiH(2)F(+). The latter species reacts in turn with SiH(4) and GeF(4) so to form SiH(3)(+) and SiHF(2)(+), respectively. The potential energy profiles conceivably involved in these reactions were investigated by ab initio calculations performed at the MP2 and coupled cluster (CCSD(T)) level of theory.

7.
Nanomaterials (Basel) ; 10(6)2020 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-32585978

RESUMO

Sn-modification of TiO2 photocatalysts has been recently proposed as a suitable strategy to improve pollutant degradation as well as hydrogen production. In particular, visible light activity could be promoted by doping with Sn2+ species, which are, however, thermally unstable. Co-promotion with N and Sn has been shown to lead to synergistic effects in terms of visible light activity, but the underlying mechanism has, so far, been poorly understood due to the system complexity. Here, the structural, optical, and electronic properties of N,Sn-copromoted, nanostructured TiO2 from sol-gel synthesis were investigated: the Sn/Ti molar content was varied in the 0-20% range and different post-treatments (calcination and low temperature hydrothermal treatment) were adopted in order to promote the sample crystallinity. Depending on the adopted post-treatment, the optical properties present notable differences, which supports a combined role of Sn dopants and N-induced defects in visible light absorption. X-ray absorption spectroscopy at the Ti K-edge and Sn L2,3-edges shed light onto the electronic properties and structure of both Ti and Sn species, evidencing a marked difference at the Sn L2,3-edges between the samples with 20% and 5% Sn/Ti ratio, showing, in the latter case, the presence of tin in a partially reduced state.

8.
Eur J Mass Spectrom (Chichester) ; 15(2): 209-20, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19423906

RESUMO

The positive ion chemistry occurring in silane/nitrogen trifluoride gaseous mixtures has been investigated by ion trap mass spectrometry. Reaction sequences and rate constants have been determined for the processes involving the primary ions SiH(n)(+) (n = 0-3) and NF(x)(+) (x = 1-3) and the secondary ions obtained from their reactions with SiH(4) and NF(3). The SiH(n)(+) efficiently react with NF(3) and undergo cascades of abstraction and scrambling reactions which form the fluorinated and perfluorinated cations SiHF(m)(+) (m = 1, 2), SiH(2)F(+) and SiF(x)(+) (x = 0-3). Fluorinated Si(2)- clusters such as Si(2)H(2)F(+), Si(2)H(3)F(+) and Si(2)H(5)F(+) were also observed. The reaction of both SiH(3)(+) and SiH(2)F(+) with NF(3) produces the elusive fluoronitrenium ion NHF(+). Any NF(x)(+) reacts with SiH(4) mainly by charge transfer. Additional ionic products are, however, observed which suggest intimate reaction complexes. Worth mentioning is the formation of SiNH(2)(+) from the reaction of both NF(+) and NHF(+) with SiH(4). The primary ions NF(2)(+) and SiH(2)(+) are also "sink" species in our observed chemistry.

9.
Res Psychother ; 22(2): 378, 2019 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-32913803

RESUMO

There is an abundance of literature investigating the relationship between self-writing and well-being in cases of trauma or life-changing events, but no such research has assessed the value of keeping a daily diary in promoting small changes, describing an individual's identity in its slow, but realistic evolution. This study examined how the use of diary as a narration tool contributed to improving a patient's awareness of his personal emotions and feelings during a course of psychotherapy. It investigated the changes occurring in the prevailing writing style of a 200-page diary written by a patient suffering from hypochondria over a period of two and a half years. Sentences relating to the need for change, to the self, to suffering and to the function attributed to the self-writing activity were analyzed on the basis of specific criteria deriving from dialogical self theory, which conceptualizes ways to adopt new identity positions during the course of change. Respondent validation identified a good correspondence between the findings of the textual analysis and the writer's own point of view. Results showed an improvement in awareness of moods and feelings. Identity positions became more integrated and writing more enjoyable. These findings demonstrate the potential of innovative use of diary writing as a longitudinal tool for consolidating strategies for change and as an additional means for assessing psychotherapy efficacy. Writing a diary proved effective both in supporting the patient's personal reflections and changes and in making it easier for him to share his thoughts with the therapist.

10.
J Mass Spectrom ; 43(10): 1320-33, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18366143

RESUMO

The ion-molecule reactions occurring in GeH(4)/NF(3), GeH(4)/SF(6), and GeH(4)/SiF(4) gaseous mixtures have been investigated by ion trap mass spectrometry and ab initio calculations. While the NF(x)(+) (x=1-3) react with GeH(4) mainly by the exothermic charge transfer, the open-shell Ge(+) and GeH(2)(+) undergo the efficient F-atom abstraction from NF(3) and form GeF(+) and F-GeH(2)(+) as the only ionic products. The mechanisms of these two processes are quite similar and involve the formation of the fluorine-coordinated complexes Ge-F-NF(2)(+) and H(2)Ge-F-NF(2)(+), their subsequent crossing to the significantly more stable isomers FGe-NF(2)(+) and F-GeH(2)-NF(2)(+), and the eventual dissociation of these ions into GeF(+) (or F-GeH(2)(+)) and NF(2). The closed-shell GeH(+) and GeH(3)(+) are instead much less reactive towards NF(3), and the only observed process is the less efficient formation of GeF(+) from GeH(+). The theoretical investigation of this unusual H/F exchange reaction suggests the involvement of vibrationally-hot GeH(+). Passing from NF(3) to SF(6) and SiF(4), the average strength of the M-F bond increases from 70 to 79 and 142 kcal mol(-1), and in fact the only process observed by reacting GeH(n)(+) (n=0-3) with SF(6) and SiF(4) is the little efficient F-atom abstraction from SF(6) by Ge(+). Irrespective of the experimental conditions, we did not observe any ionic product of Ge-N, Ge-S, or Ge-Si connectivity. This is in line with the previously observed exclusive formation of GeF(+) from the reaction between Ge(+) and C-F compounds such as CH(3)F. Additionally observed processes include in particular the conceivable formation of the elusive thiohypofluorous acid FSH from the reaction between SF(+) and GeH(4).

11.
Eur J Mass Spectrom (Chichester) ; 13(6): 377-84, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18417758

RESUMO

The gas phase ion-molecule reactions in positively and negatively ionized germane/diborane mixtures have been studied by ion trap mass spectrometry. Reaction sequences and rate constants for the most interesting processes have been determined. In positive ionization, formation of Ge-B bonds exclusively occurs through condensation reactions of B(n)H(m)(+) ions with germane, followed by H(2) or BH(3) loss. No reactions of ions from germane with B(2)H(6) were observed under the experimental conditions used here. In negative ionization, the Ge(n)H(m)(-) (n = 1, 2) ion families react with diborane to yield the Ge(n)B(p)H(q)(-) (p = 1, 2) ions, again via dehydrogenation and BH(3) loss, while diborane anions proved to be unreactive. In both positive and negative ionization, Ge-B ions reach appreciable abundances. The present results afford fundamental information about the intrinsic reactivity of gas-phase ions and provide valuable indications about the first nucleation steps ultimately leading to amorphous Ge and B-doped semiconductor materials by chemical vapor deposition methods.

12.
J Mass Spectrom ; 40(5): 591-8, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15724272

RESUMO

The gas-phase ion chemistry of silane-allene-ammonia, germane-allene (or propyne)-ammonia (or phosphine) systems was studied by ion trap mass spectrometry. Reaction sequences were determined and rate constants were measured for the main processes observed. The mixture containing silane displays higher reactivity with respect to that with germane. Comparison with analogous systems provides useful information about the reactivity of different hydrocarbon molecules and the different affinities of silicon and germanium towards nitrogen and phosphorus. The most interesting product ions observed are those containing Si (or Ge), C and N (or P) elements together, as these ion species may be considered precursors of doped amorphous carbides, which are widely used in semiconductor devices.

13.
J Mass Spectrom ; 39(6): 665-71, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15236305

RESUMO

The gas-phase ion chemistry of allene-phosphine and silane-allene-phosphine mixtures was studied by ion trap mass spectrometry. Rate constants of the main processes were measured and compared with the collisional rate constants to determine the reaction efficiencies. For the binary mixture, the highest yield of C- and P-containing ions is obtained with a 1 : 1 partial pressure ratio among the reagents. In the ternary mixture, formation of ion species containing Si, C and P together is mainly achieved in reactions of Si/P ions with allene, with a lower contribution from reactions of Si/C and C/P ions with phosphine and silane, respectively. The formation of ternary ion clusters is related to their possible role as precursors of amorphous silicon carbides doped with phosphorus, obtained by deposition from properly activated silane-allene-phosphine mixtures.

14.
J Mass Spectrom ; 39(6): 682-90, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15236307

RESUMO

The gas-phase ion chemistry of propyne-phosphine and silane-propyne-phosphine mixtures was studied by ion trap mass spectrometry. For the binary mixture, the effect of different partial pressures of the reagents on the yield of C and P-containing ions was evaluated. Reaction sequences and rate constants were determined and reaction efficiencies were calculated from comparison of experimental and collisional rate constants. In the ternary silane-propyne-phosphine systems, the reaction pathways leading to formation of Si(m)C(n)P(p)H(q) (+) ions were determined and the rate constants of the most important steps were measured. For some ion species, selected by double isolation procedures (MS/MS), the low ion abundances prevented determination of the reaction rate constants. Si, C and P-containing ions are mainly produced in reactions of Si(m)P(p)H(q) (+) ions with propyne, while the reactivity of the Si(m)C(n)H(q) (+) ions towards PH(3) and of the C(n)P(p)H(q) (+) ions towards SiH(4) is very low. The formation of hydrogenated Si--C--P ions is interesting for their possible role as precursors of amorphous silicon carbides doped with phosphorus, obtained in a single step, by deposition from properly activated silane-propyne-phosphine mixtures.

16.
J Mass Spectrom ; 44(5): 725-34, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19160450

RESUMO

The gas phase ion chemistry of silane/hydrogen sulfide and germane/hydrogen sulfide mixtures was studied by ion trap mass spectrometry (ITMS), in both positive and negative ionization mode. In positive ionization, formation of X/S (X = Si, Ge) mixed ions mainly takes place via reactions of silane or germane ions with H(2)S, through condensation followed by dehydrogenation. This is particularly evident in the system with silane. On the other side, reactions of H(n)S(2)(+) ions with XH(4) (X = Si, Ge) invariably lead to formation of a single X-S bond. In negative ionization, a more limited number of mixed ion species is detected, but their overall abundance reaches appreciable values, especially in the SiH(4)/H(2)S system. Present results clearly indicate that ion processes play an important role in formation and growth of clusters eventually leading to deposition of amorphous solids in chemical vapor deposition (CVD) processes.

17.
J Mass Spectrom ; 44(9): 1348-58, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19618400

RESUMO

The gas-phase reaction of CH(3)(+) with NF(3) was investigated by ion trap mass spectrometry (ITMS). The observed products include NF(2)(+) and CH(2)F(+). Under the same experimental conditions, SiH(3)(+) reacts with NF(3) and forms up to six ionic products, namely (in order of decreasing efficiency) NF(2)(+), SiH(2)F(+), SiHF(2)(+), SiF(+), SiHF(+), and NHF(+). The GeH(3)(+) cation is instead totally unreactive toward NF(3). The different reactivity of XH(3)(+) (X = C, Si, Ge) toward NF(3) has been rationalized by ab initio calculations performed at the MP2 and coupled cluster level of theory. In the reaction of both CH(3)(+) and SiH(3)(+), the kinetically relevant intermediate is the fluorine-coordinated isomer H(3)X-F-NF(2)(+) (X = C, Si). This species forms from the exoergic attack of XH(3)(+) to one of the F atoms of NF(3) and undergoes dissociation and isomerization processes which eventually result in the experimentally observed products. The nitrogen-coordinated isomers H(3)X-NF(3)(+) (X = C, Si) were located as minimum-energy structures but do not play an active role in the reaction mechanism. The inertness of GeH(3)(+) toward NF(3) is also explained by the endoergic character of the dissociation processes involving the H(3)Ge-F-NF(2)(+) isomer.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA