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1.
Phys Rev Lett ; 130(8): 089901, 2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36898127

RESUMO

This corrects the article DOI: 10.1103/PhysRevLett.129.180402.

3.
Phys Chem Chem Phys ; 20(9): 6198-6210, 2018 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-29431772

RESUMO

Cyclopropyl cyanide and other simple nitriles detected in Titan's atmosphere could be precursors leading to the formation of organic macromolecules in the atmosphere of Saturn's largest satellite. Proposing a thermodynamically possible mechanism that explains their formation and supports experimental results represents a difficult challenge. Experiments done in the Atomic and Molecular Physics Laboratory at the University of Trento (AMPL) have studied the ion-molecule reaction between cyclopropyl cyanide and its protonated form, with reaction products being characterized by mass spectrometry. In addition to the expected ion-molecule adduct stabilized by non-covalent long-range interactions, in this work we prove that another distinct species having the same mass to charge ratio (m/z) of 135 is also produced. Moreover, from a previous study of the neutral cyclopropyl cyanide potential energy surface (PES) which shows a partial biradical character it has been possible to characterize the formation through the bimolecular reaction of a new covalent cyclic organic molecule. Calculations have been carried out at the ab initio Møller-Plesset (MP2) level of theory, ensuring the connectivity of the stationary points by using the intrinsic reaction coordinate (IRC) procedure. In order to characterize the reaction transition state, multireference calculations were done using a complete active space involving six electrons and six molecular orbitals [CAS (6 e-, 6 m.o.)]. This study opens the possibility of exploring the formation of new organic molecules by gaseous phase ion-molecule interaction schemes, with such molecules having relevance in interstellar space and in astrobiology (and may be involved in prebiotic molecular evolution).

4.
Clin Transl Oncol ; 20(7): 862-869, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29178019

RESUMO

INTRODUCTION: This study aimed to describe the efficacy of fulvestrant 500 mg in postmenopausal women with estrogen receptor (ER)-positive advanced/metastatic breast cancer who had disease progression after receiving anti-estrogen therapy in clinical practice, getting real-world data. MATERIALS AND METHODS: Multicenter, retrospective, observational study conducted in Spain. Postmenopausal women with locally advanced/metastatic ER-positive breast cancer who received treatment with fulvestrant 500 mg after progression with a previous anti-estrogen therapy were eligible. The primary endpoint was progression-free survival (PFS); secondary endpoints were overall survival (OS), clinical benefit rate (CBR), duration of clinical benefit (DoCB), and safety profile. RESULTS: A total of 263 women were evaluated (median age, 65.8 years). At a median follow-up of 21.5 months, median PFS and OS were 10.6 and 43.2 months, respectively. PFS according to 1st, 2nd, 3rd, and ≥ 4th lines were 11.5, 10.6, 9.9, and 8.5 months, respectively (p = 0.0245). PFS in patients with visceral involvement was 10 months vs 10.6 months in patients without visceral involvement (p = 0.6604), 9.6 months in patients with high Ki67 vs 10 months in patients with low Ki67 (p = 0.7224), and 10.2 months in HER2+ patients vs 10.3 months in HER2- patients (p = 0.6809). The CBR was 56.5% and the DoCB was 18.4 months. The most frequently adverse events were injection site pain (10.3%) and musculoskeletal disorders (7.6%). CONCLUSIONS: Fulvestrant 500 mg administered in clinical practice was shown to be effective (PFS, 10.6 months; CBR, 56.5%) and well tolerated, in accordance with previous trials.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Carcinoma Ductal de Mama/tratamento farmacológico , Carcinoma Lobular/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos , Estradiol/análogos & derivados , Pós-Menopausa , Idoso , Antineoplásicos Hormonais/uso terapêutico , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/metabolismo , Carcinoma Ductal de Mama/secundário , Carcinoma Lobular/metabolismo , Carcinoma Lobular/secundário , Estradiol/uso terapêutico , Feminino , Seguimentos , Fulvestranto , Humanos , Metástase Linfática , Pessoa de Meia-Idade , Prognóstico , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Estudos Retrospectivos
5.
J Chem Phys ; 146(13): 134301, 2017 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-28390361

RESUMO

Gas phase reactive collisions between lithium ions and i-C3H7X (X = Br, OH) molecules have been studied under single collision conditions in the center of mass (CM) 0.01-10.00 eV energy range using a radiofrequency-guided ion beam apparatus. Mass spectrometry analysis of the products did show the presence of [C3H6-Li]+, [HX-Li]+, C3H7+, and C2H3+ as well as of the [Li-i-C3H7Br]+ adduct while [Li-i-C3H7OH]+ was hardly detected. For all these reactive processes, the corresponding cross sections have been measured in absolute units as a function of the CM collision energy. Quantum chemistry ab initio calculations done at the second order Möller Plesset level have provided relevant information on the topology of the potential energy surfaces (PESs) where a reaction takes place allowing the characterization of the stationary points on the respective PESs along their reaction pathways. The connectivity of the different stationary points localized on the PESs was ensured by using the intrinsic reaction coordinate (IRC) method, confirming the adiabatic character of the reactions. The main topology features of the reactive PESs, in the absence of dynamical calculations, were used to interpret at the qualitative level the behavior of the experimental excitations functions, evidencing the role played by the potential energy barriers on the experimental dynamics of the reactions. Reaction rate constants at 303.2 K for different reactions have been calculated from measured excitation functions.

6.
Clin Transl Oncol ; 19(2): 149-161, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27314861

RESUMO

Metastatic breast cancer is a heterogeneous disease that presents in varying forms, and a growing number of therapeutic options makes it difficult to determine the best choice in each particular situation. When selecting a systemic treatment, it is important to consider the medication administered in the previous stages, such as acquired resistance, type of progression, time to relapse, tumor aggressiveness, age, comorbidities, pre- and post-menopausal status, and patient preferences. Moreover, tumor genomic signatures can identify different subtypes, which can be used to create patient profiles and design specific therapies. However, there is no consensus regarding the best treatment sequence for each subgroup of patients. During the SABCC Congress of 2014, specialized breast cancer oncologists from referral hospitals in Europe met to define patient profiles and to determine specific treatment sequences for each one. Conclusions were then debated in a final meeting in which a relative degree of consensus for each treatment sequence was established. Four patient profiles were defined according to established breast cancer phenotypes: pre-menopausal patients with luminal subtype, post-menopausal patients with luminal subtype, patients with triple-negative subtype, and patients with HER2-positive subtype. A treatment sequence was then defined, consisting of hormonal therapy with tamoxifen, aromatase inhibitors, fulvestrant, and mTOR inhibitors for pre- and post-menopausal patien ts; a chemotherapy sequence for the first, second, and further lines for luminal and triple-negative patients; and an optimal sequence for treatment with new antiHER2 therapies. Finally, a document detailing all treatment sequences, that had the agreement of all the oncologists, was drawn up as a guideline and advocacy tool for professionals treating patients with this disease.


Assuntos
Antineoplásicos/normas , Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Feminino , Humanos , Prognóstico , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo
7.
J Phys Chem A ; 120(27): 4758-69, 2016 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-26811987

RESUMO

Dehydrohalogenation and dehydration reactions of gas-phase i-C3H7Br and i-C3H7OH molecules induced by collision with Na(+), all participants being in their electronic ground state, were studied experimentally in our laboratory using a radiofrequency-guided ion beam apparatus and covering the 0.10-10.00 eV center of mass (CM) energy range. In Na(+) + i-C3H7Br collisions the formation of [C3H6-Na](+) and [HBr-Na](+) by dehydrohalogenation was observed and quantified, as well as that of the ion-molecule adduct [Na-i-C3H7Br](+) together with its decomposition products C3H7(+) and NaBr. In Na(+) + i-C3H7OH collisions the dehydration product [H2O-Na](+) was also found, while [C3H6-Na](+) was hardly detected. Moreover, the [Na-i-C3H7OH](+) adduct formation as well as its decomposition into C3H7(+) and NaOH were also quantified. For all these processes, absolute reaction cross sections were measured as a function of the CM collision energy. From measured excitation functions, rate constants for the formation of [C3H6-Na](+), [HBr-Na](+), and [H2O-Na](+) at 303 K were obtained. Complementing the experiments, exhaustive ab initio structure calculations at the MP2 level of theory were performed, giving information on the most relevant features of the potential energy surfaces (PESs) where the dehydrohalogenation, dehydration, and decomposition reactions take place adiabatically for both collision systems. On these PESs different stationary points associated with potential energy minima and transition state barriers were characterized, and their connectivity was ensured using the intrinsic-reaction-coordinate method. The main topology features of the ab initio calculated PESs allowed a qualitative interpretation of the experimental data also exposing the role of the sodium ion as a catalyst in elimination reactions.

8.
Rev Esp Med Nucl Imagen Mol ; 34(3): 167-72, 2015.
Artigo em Espanhol | MEDLINE | ID: mdl-25466396

RESUMO

OBJECTIVES: To evaluate if the estimation of the maximal oxygen consumption (MO2C) in METs (metabolic equivalents) by means of the table proposed in the guidelines of the Spanish Society of Cardiology is a sufficiently reliable method when applied to the bicycle exercise test. MATERIAL AND METHODS: The MO2C in METs was obtained by gas-exchange analysis on bicycle ergometer tests in 97 healthy subjects (group i). It was compared with the estimate of METs using the table in which only watts and patient's weight were included. A better-adjusted formula was validated in 289 subjects with normal exercise myocardial perfusion gated-SPECT (group ii) using the introduction of clinical and ergometric variables. RESULTS: In group i individuals a good correlation between METs estimated with the table and those obtained through gas-exchange analysis (CCI: 0.93) was observed. However, the best adjusted formula to estimate METs in group ii subjects included watts, body mass index (BMI), age and gender (METS=11.820-0.054×age-0.189×BMI+1.031×gender+0.020×watts) (women: 0, men: 1). This formula allowed the reclassification of 46.9% of group ii subjects into the category <5METs versus the estimation by table. CONCLUSIONS: Estimating the METs with the conventional table is reliable. However, the best adjustment in subjects with normal bicycle exercise SPECT was obtained when, in addition to watts and BMI, age and gender were also considered.


Assuntos
Algoritmos , Teste de Esforço , Consumo de Oxigênio , Adulto , Idoso , Índice de Massa Corporal , Tomografia Computadorizada por Emissão de Fóton Único de Sincronização Cardíaca , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Troca Gasosa Pulmonar , Método Simples-Cego
9.
J Chem Phys ; 141(16): 164310, 2014 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-25362302

RESUMO

Collisions between potassium ions and neutral i-C3H7Br and i-C3H7OH, all in their electronic ground state, have been studied in the 0.10-10.00 eV center of mass (CM) collision energy range, using the radiofrequency-guided ion beam technique. In K(+) + i-C3H7Br collisions KHBr(+) formation was observed and quantified, while the analogous KH2O(+) formation in K(+) + i-C3H7OH was hardly detected. Moreover, formation of the ion-molecule adducts and their decomposition leading to C3H7(+) and either KBr or KOH, respectively, have been observed. For all these processes, absolute cross-sections were measured as a function of the CM collision energy. Ab initio structure calculations at the MP2 level have given information about the potential energy surfaces (PESs) involved. In these, different stationary points have been characterized using the reaction coordinate method, their connectivity being ensured by using the intrinsic-reaction-coordinate method. From the measured excitation function for KHBr(+) formation the corresponding thermal rate constant at 303 K has been calculated. The topology of the calculated PESs allows an interpretation of the main features of the reaction dynamics of both systems, and in particular evidence the important role played by the potential energy wells in controlling the reactivity for the different reaction channels.

10.
J Chem Phys ; 137(15): 154202, 2012 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-23083158

RESUMO

Inelastic electronically non-adiabatic reactions between Na(+) ions and neutral ZnBr(2) molecules, both in their electronic ground state, have been studied using crossed beams techniques and measuring the decaying emission radiation of the excited species produced. The fluorescent emission corresponding to Na(3 (2)P) produced by a charge transfer reaction was observed, as well as that corresponding to the decay of Zn(4s 5s (3)S), generated by dissociation of the neutral target molecule, to Zn(4s 4p (3)P). The phosphorescent decaying emission of Zn*(4s 4p (3)P) to the zinc ground state was also observed. For each emission process, the cross section energy dependences have been measured in the 0.10-3.50 keV energy range in the laboratory system. The ground electronic state of the (NaZnBr(2))(+) collision system has been characterized by ab initio chemical structure calculations at the second order Möller-Plesset perturbation level of theory using pseudo-potentials. By performing restricted open shell Hartree-Fock calculations for C(2v) geometries, four singlet and four triplet potential energy surfaces of the system have been calculated and used to interpret qualitatively the observed reactions. A simple two-state dynamical model is presented that allows an estimation of the maximum values for measured cross sections at high collision energies to be made.

11.
Phys Chem Chem Phys ; 13(35): 15977-84, 2011 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-21826291

RESUMO

The association reactions of benzene molecules with alkali ions M(+) (Li(+), Na(+) and K(+)) under single collision conditions have been studied using a radiofrequency-guided-ion-beam apparatus and mass spectrometry characterization of the different adducts. Cross-section energy dependences for [M-C(6)H(6)](+) adduct formation have been measured at collision energies up to 1.20 eV in the center of mass frame. All excitation functions decrease when collision energy increases, showing the expected behaviour for barrierless reactions. From ab initio chemical structure calculations at the MP2(full) level, the formation of the adducts makes evident the alkali ion-benzene non-covalent chemical bond. The cross-section energy dependence and the role of radiative cooling rates and unimolecular decomposition on the stabilization of the energized collision complex are also discussed.

12.
J Phys Chem A ; 113(52): 14766-73, 2009 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-19691335

RESUMO

The association reactions between Li(+), K(+), and Rb(+) (M) and butanone and cyclohexanone molecules under single collision conditions have been studied using a radiofrequency-guided ion-beam apparatus, characterizing the adducts by mass spectrometry. The excitation function for the [M-(molecule)](+) adducts (in arbitrary units) has been obtained at low collision energies in the 0.10 eV up to a few eV range in the center of mass frame. The measured relative cross sections decrease when collision energy increases, showing the expected energy dependence for adduct formation. The energetics and structure of the different adducts have been calculated ab initio at the MP2(full) level, showing that the M(+)-molecule interaction takes place through the carbonyl oxygen atom, as an example of a nontypical covalent chemical bond. The cross-section energy dependence and the role of radiative cooling rates allowing the stabilization of the collision complexes are also discussed.

13.
J Chem Phys ; 131(2): 024306, 2009 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-19603990

RESUMO

Reactive collisions between Li(+) ions and i-C(3)H(7)Cl molecules have been studied in the 0.20-12.00 eV center-of-mass energy range using an octopole radio frequency guided-ion beam apparatus recently developed in our laboratory. At low collision energies, dehydrohalogenation reactions giving rise to Li(C(3)H(6))(+) and Li(HCl)(+) are the main reaction channels, while at higher ones C(3)H(7)(+) and C(2)H(3)(+) become dominant, all their reactive cross sections having been measured as a function of the collision energy. To obtain information about the potential energy surfaces (PESs) on which the reactive processes take place, ab initio calculations at the MP2 level have been performed. For dehydrohalogenations, the reactive ground singlet PES shows ion-molecule adduct formation in both the reactant and product sides of the surface. Following the minimum energy path connecting both minima, an unstable intermediate and the corresponding barriers, both lying below the reactant's energy, have been characterized. The entrance channel ion-molecule adduct is also involved in the formation of C(3)H(7)(+), which then generates C(2)H(3)(+) via an CH(4) unimolecular elimination. A qualitative interpretation of the experimental results based on ab initio calculations is also included.

14.
J Perinatol ; 29(3): 201-4, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19052553

RESUMO

OBJECTIVE: To describe fetal macrocrania including prenatal diagnosis, delivery considerations and clinical outcomes. STUDY DESIGN: A retrospective case series was developed by reviewing 26 885 ultrasounds performed between 1 March 2003 and 30 June 2007 for the prenatal diagnosis of macrocrania. Medical records of each mother/infant pair were reviewed for demographic information, ultrasound findings, obstetric management and outcomes. RESULT: Twenty-three fetuses were diagnosed with macrocrania. Median gestational age at diagnosis was 31.1 weeks (range 18.3-38.1) and at delivery was 36.9 weeks (range 30.7-39.9). Fifteen patients (65%) underwent amniocentesis for karyotype; none were aneuploid but one had a duplication on chromosome 7. All the 23 infants were liveborn. Twenty-one deliveries were by Cesarean (91%), with thirteen of these by classical incision (62%). Of the infants, 5 (22%) died shortly after birth, 16 (70%) were stabilized in the neonatal intensive care unit and were discharged alive and 2 (8%) were transferred to another center and subsequently died. Eighteen babies required ventriculoperitoneal shunting (78%). CONCLUSION: Macrocrania is a diagnosis usually made in children but can also be made prenatally. Fetal macrocrania is usually a result of ventriculomegaly due to an obstructive process to cerebrospinal fluid flow. Abdominal delivery is usually required, often necessitating a classical uterine incision. Targeted ultrasonography, extensive counseling of parents and delivery at a tertiary care center with availability of neurosurgery is recommended.


Assuntos
Cesárea , Doenças Fetais/diagnóstico por imagem , Crânio/anormalidades , Crânio/diagnóstico por imagem , Ultrassonografia Pré-Natal , Centros Médicos Acadêmicos , Adolescente , Adulto , Amniocentese , Estudos de Coortes , Feminino , Idade Gestacional , Humanos , Hidrocefalia/diagnóstico por imagem , Hidrocefalia/cirurgia , Recém-Nascido , Gravidez , Resultado da Gravidez , Estudos Retrospectivos , Análise de Sobrevida , Derivação Ventriculoperitoneal , Adulto Jovem
18.
Rev. toxicol ; 24(1): 56-58, 2007. ilus
Artigo em Espanhol | IBECS | ID: ibc-75361

RESUMO

Recientemente hemos observado dos intoxicaciones en ganado vacuno lechero, en granjas de Cataluña, debidas a la ingestión de estramonio (Datura stramonium). La planta había sido en ambos casos erróneamente recolectada junto con el maíz empleado para la alimentación de los animales. El cuadro fue leve y, básicamente, cursó con problemas digestivos y descenso en la producción lechera, y remitió con la retirada del alimento contaminado. Debido a factores ambientales y económicos, el problema podría estar en aumento(AU)


Recently, two poisoning episodes produced by Jimson weed (Datura stramonium) consumption have been observed in dairy cattle farms from Catalonia. The plant was mistakenly gathered, in both cases, together with corn used for animal feed. The set of symptoms were slight, basically gastrointestinal disorders and decrease of milk production, and animal recovery was observed as soon as the contaminated feed was removed. This problematic situation could be increasing in prevalence due to environmental and economic factors(AU)


Assuntos
Animais , Bovinos/anatomia & histologia , Bovinos/microbiologia , Doenças dos Bovinos/diagnóstico , Datura stramonium/efeitos adversos , Datura stramonium/toxicidade , Atropina/toxicidade , Escopolamina/toxicidade , Datura stramonium/intoxicação , Cromatografia Gasosa/métodos , Alimentos Formulados/efeitos adversos , Alimentos Formulados/toxicidade
19.
J Chem Phys ; 123(12): 124314, 2005 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-16392489

RESUMO

Inelastic and charge-transfer excitation processes in collisions between ground-state neutral Mg atoms and K+ ions have been studied by means of a crossed molecular-beam technique. Decay fluorescent emissions from Mg(3 1P1),Mg(4 3S1), and Mg(3s(1)3d(1), 3(3)D3,2,1) as well as the phosphorescent emission due to Mg(3 3P1) have been observed from excited Mg atoms and the charge-transfer emission decays from K(4 2P 3/2,1/2), K(5 2P 3/2, 1/2), K(6 2S 1/2), and K(4 2D 5/2, 3/2) for excited K atoms. The corresponding absolute cross-sections values versus collision energy functions were determined in the 0.10-3.80 keV laboratory energy range. In order to interpret the experimental results, accurate ab initio full configuration-interaction calculations using pseudopotentials have been performed for the (Mg-K)+ system, giving a manifold of adiabatic singlet and triplet potential-energy curves correlating with the different collision channels, which allow a qualitative interpretation of the emission excitation functions measured for the different processes studied. A comparative study with other Mg-alkali ion systems previously studied is also included.

20.
J Chem Phys ; 121(11): 5284-92, 2004 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-15352822

RESUMO

Inelastic collision processes between neutral Mg atoms and Rb(+) ions, both in their ground states, have been studied by means of a crossed molecular beam technique measuring the decay fluorescence of the excited species formed. Emissions corresponding to Mg(3 (1)P(1)), Mg(3 (3)D(3,2,1)), and Mg(4 (3)S(1)), formed by direct target excitation, Rb(5 (2)P(3/2,1/2)), Rb(6 (2)P(3/2,1/2)) produced by electron capture and also the phosphorescent emission due to decay of Mg(3 (3)P(1)), have been detected and the corresponding absolute cross-section values measured both as total values and resolved into their J states. No polarization measurements could be made. Ab initio calculations using pseudopotentials have been performed and from these a manifold of adiabatic energy curves correlating with the different entry and exit channels have been obtained, allowing to propose a qualitative interpretation of the results, such as the shape of the cross section vs energy for different transitions and the oscillating nature of the branching ratios due to interference effects.

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