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1.
Angew Chem Int Ed Engl ; 62(27): e202302809, 2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37075196

RESUMO

Here, we report a new class of peptidomimetic macrocycles with well-defined three-dimensional structures and low conformational flexibility. They are assembled from fused-ring spiro-ladder oligomers (spiroligomers) by modular solid-phase synthesis. Two-dimensional nuclear magnetic resonance confirms their shape persistency. Triangular macrocycles of tunable sizes assemble into membranes with atomically precise pores, which exhibit size and shape-dependent molecular sieving towards a series of structurally similar compounds. The exceptional structural diversity and stability of spiroligomer-based macrocycles will be explored for more applications.

2.
J Proteome Res ; 20(6): 3256-3267, 2021 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-33950683

RESUMO

Angiotensin II type 1 receptors (AT1Rs) are one of the most widely studied G-protein-coupled receptors. To fully appreciate the diversity in cellular signaling profiles activated by AT1R transducer-biased ligands, we utilized peroxidase-catalyzed proximity labeling to capture proteins in close proximity to AT1Rs in response to six different ligands: angiotensin II (full agonist), S1I8 (partial agonist), TRV055 and TRV056 (G-protein-biased agonists), and TRV026 and TRV027 (ß-arrestin-biased agonists) at 90 s, 10 min, and 60 min after stimulation (ProteomeXchange Identifier PXD023814). We systematically analyzed the kinetics of AT1R trafficking and determined that distinct ligands lead AT1R to different cellular compartments for downstream signaling activation and receptor degradation/recycling. Distinct proximity labeling of proteins from a number of functional classes, including GTPases, adaptor proteins, and kinases, was activated by different ligands suggesting unique signaling and physiological roles of the AT1R. Ligands within the same class, that is, either G-protein-biased or ß-arrestin-biased, shared high similarity in their labeling profiles. A comparison between ligand classes revealed distinct signaling activation such as greater labeling by G-protein-biased ligands on ESCRT-0 complex proteins that act as the sorting machinery for ubiquitinated proteins. Our study provides a comprehensive analysis of AT1R receptor-trafficking kinetics and signaling activation profiles induced by distinct classes of ligands.


Assuntos
Proteômica , Receptor Tipo 1 de Angiotensina , Ligantes , Receptor Tipo 1 de Angiotensina/genética , Receptor Tipo 1 de Angiotensina/metabolismo , Transdução de Sinais , beta-Arrestinas
3.
Clin Infect Dis ; 73(2): 183-191, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-32277809

RESUMO

BACKGROUND: We evaluated the efficacy, pharmacokinetics (PK), and safety of clofazimine (CFZ) in patients living with human immunodeficiency virus (HIV) with cryptosporidiosis. METHODS: We performed a randomized, double-blind, placebo-controlled study. Primary outcomes in part A were reduction in Cryptosporidium shedding, safety, and PK. Primary analysis was according to protocol (ATP). Part B of the study compared CFZ PK in matched individuals living with HIV without cryptosporidiosis. RESULTS: Twenty part A and 10 part B participants completed the study ATP. Almost all part A participants had high viral loads and low CD4 counts, consistent with failure of antiretroviral (ARV) therapy. At study entry, the part A CFZ group had higher Cryptosporidium shedding, total stool weight, and more diarrheal episodes compared with the placebo group. Over the inpatient period, compared with those who received placebo, the CFZ group Cryptosporidium shedding increased by 2.17 log2 Cryptosporidium per gram stool (95% upper confidence limit, 3.82), total stool weight decreased by 45.3 g (P = .37), and number of diarrheal episodes increased by 2.32 (P = .87). The most frequent solicited adverse effects were diarrhea, abdominal pain, and malaise. One placebo and 3 CFZ participants died during the study. Plasma levels of CFZ in participants with cryptosporidiosis were 2-fold lower than in part B controls. CONCLUSIONS: Our findings do not support the efficacy of CFZ for the treatment of cryptosporidiosis in a severely immunocompromised HIV population. However, this trial demonstrates a pathway to assess the therapeutic potential of drugs for cryptosporidiosis treatment. Screening persons living with HIV for diarrhea, and especially Cryptosporidium infection, may identify those failing ARV therapy. CLINICAL TRIALS REGISTRATION: NCT03341767.


Assuntos
Pesquisa Biomédica , Criptosporidiose , Cryptosporidium , Infecções por HIV , Adulto , Clofazimina/uso terapêutico , Criptosporidiose/complicações , Criptosporidiose/tratamento farmacológico , Diarreia , HIV , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Humanos
4.
J Autoimmun ; 97: 48-58, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30391024

RESUMO

Convergent evidence from multiple and independent genetics studies implicate a small number of genes that predispose individuals to multiple autoimmune disorders (AuD). These intersecting loci reinforced the hypothesis that disorders with overlapping etiology group into a cluster of closely related genes within a whole genome molecular interaction network. We tested the hypothesis that "biological network proximity" within a whole genome molecular interaction network can be used to inform the search for multigene inheritance. Using a set of nine previously published genome wide association studies (GWAS) of AuD genes, we generated AuD-specific molecular interaction networks to identify networks of associated genes. We show that all nine "seed genes" can be connected within a 35-member network via interactions with 26 connecting genes. We show that this network is more connected than expected by chance, and 13 of the connecting genes showed association with multiple AuD upon GWAS reanalysis. Furthermore, we report association of SNPs in five new genes (IL10RA, DGKA, GRB2, STAT5A, and NFATC2) which were not previously considered as AuD candidates, and show significant association in novel disease samples of Crohn's disease and systemic lupus erythematosus. Furthermore, we show that the connecting genes show no association in four non-AuD GWAS. Finally, we test the connecting genes in psoriasis GWAS, and show association to previously identified loci and report new loci. These findings support the hypothesis that molecular interaction networks can be used to inform the search for multigene disease etiology, especially for disorders with overlapping etiology.


Assuntos
Alelos , Doenças Autoimunes/genética , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Doenças Autoimunes/diagnóstico , Doenças Autoimunes/metabolismo , Biologia Computacional/métodos , Perfilação da Expressão Gênica , Ligação Genética , Estudo de Associação Genômica Ampla/métodos , Humanos , Desequilíbrio de Ligação , Polimorfismo de Nucleotídeo Único
5.
Anaesthesia ; 73(6): 711-718, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29473682

RESUMO

Studies that have investigated circadian, weekday and seasonal variation in postoperative mortality have been relatively small or have been for scheduled surgery. We retrospectively tested a large mixed surgical cohort from a German tertiary care university hospital for the presence of cyclical variation in all-cause in-hospital mortality after operations performed between 2006 and 2013. We analysed mortality rates after 247,475 operations, adjusted for age, sex, comorbidities, location, urgency and duration of the surgery, and intra-operative blood transfusions. The mortality odds ratio (95%CI) after operations started in the morning (08:00-11:00) were lowest, 0.73 (0.66-0.80), p < 0.001 and highest for operations started in the afternoon (13:00-17:00), 1.29 (1.18-1.40), p < 0.001. Mortality at the weekend was the same as during the week. There was no seasonal variation in mortality, p = 0.12. However, the interference of four-yearly and ten-monthly cycle amplitudes resulted in higher mortality odds ratio (95%CI) in winter 2008-2009, 1.41 (1.18-1.69), p < 0.001, and lower mortality in spring 2011 and 2012, 0.70 (0.56-0.85) and 0.67 (0.53-0.85), p < 0.001 and p = 0.001, respectively. The ability to predict cyclical phenomena would facilitate the design of interventional studies, aimed at reducing mortality following surgery in the afternoon and when cycles interfere constructively.


Assuntos
Período Pós-Operatório , Procedimentos Cirúrgicos Operatórios/mortalidade , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Transfusão de Sangue/mortalidade , Criança , Pré-Escolar , Estudos de Coortes , Comorbidade , Feminino , Alemanha/epidemiologia , Mortalidade Hospitalar , Hospitais Universitários , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Retrospectivos , Estações do Ano , Centros de Atenção Terciária , Fatores de Tempo , Adulto Jovem
6.
Proc Natl Acad Sci U S A ; 111(51): 18132-7, 2014 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-25489068

RESUMO

Theoretical models of proton hydration with tens of water molecules indicate that the excess proton is embedded on the surface of clathrate-like cage structures with one or two water molecules in the interior. The evidence for these structures has been indirect, however, because the experimental spectra in the critical H-bonding region of the OH stretching vibrations have been too diffuse to provide band patterns that distinguish between candidate structures predicted theoretically. Here we exploit the slow cooling afforded by cryogenic ion trapping, along with isotopic substitution, to quench water clusters attached to the H3O(+) and Cs(+) ions into structures that yield well-resolved vibrational bands over the entire 215- to 3,800-cm(-1) range. The magic H3O(+)(H2O)20 cluster yields particularly clear spectral signatures that can, with the aid of ab initio predictions, be traced to specific classes of network sites in the predicted pentagonal dodecahedron H-bonded cage with the hydronium ion residing on the surface.

7.
Phys Chem Chem Phys ; 18(38): 26743-26754, 2016 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-27722600

RESUMO

We use cryogenic ion trap vibrational spectroscopy to study the structure of the protonated water pentamer, H+(H2O)5, and its fully deuterated isotopologue, D+(D2O)5, over nearly the complete infrared spectral range (220-4000 cm-1) in combination with harmonic and anharmonic electronic structure calculations as well as RRKM modelling. Isomer-selective IR-IR double-resonance measurements on the H+(H2O)5 isotopologue establish that the spectrum is due to a single constitutional isomer, thus discounting the recent analysis of the band pattern in the context of two isomers based on AIMD simulations 〈W. Kulig and N. Agmon, Phys. Chem. Chem. Phys., 2014, 16, 4933-4941〉. The evolution of the persistent bands in the D+(D2O)5 cluster allows the assignment of the fundamentals in the spectra of both isotopologues, and the simpler pattern displayed by the heavier isotopologue is consistent with the calculated spectrum for the branched, Eigen-based structure originally proposed 〈J.-C. Jiang, et al., J. Am. Chem. Soc., 2000, 122, 1398-1410〉. This pattern persists in the vibrational spectra of H+(H2O)5 in the temperature range from 13 K up to 250 K. The present study also underscores the importance of considering nuclear quantum effects in predicting the kinetic stability of these isomers at low temperatures.

8.
J Chem Phys ; 144(7): 074305, 2016 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-26896984

RESUMO

We report the vibrational signatures of a single H2O molecule occupying distinct sites of the hydration network in the Cs(+)(H2O)6 cluster. This is accomplished using isotopomer-selective IR-IR hole-burning on the Cs(+)(D2O)5(H2O) clusters formed by gas-phase exchange of a single, intact H2O molecule for D2O in the Cs(+)(D2O)6 ion. The OH stretching pattern of the Cs(+)(H2O)6 isotopologue is accurately recovered by superposition of the isotopomer spectra, thus establishing that the H2O incorporation is random and that the OH stretching manifold is largely due to contributions from decoupled water molecules. This behavior enables a powerful new way to extract structural information from vibrational spectra of size-selected clusters by explicitly identifying the local environments responsible for specific infrared features. The Cs(+)(H2O)6 structure was unambiguously assigned to the 4.1.1 isomer (a homodromic water tetramer with two additional flanking water molecules) from the fact that its computed IR spectrum matches the observed overall pattern and recovers the embedded correlations in the two OH stretching bands of the water molecule in the Cs(+)(D2O)5(H2O) isotopomers. The 4.1.1 isomer is the lowest in energy among other candidate networks at advanced (e.g., CCSD(T)) levels of theoretical treatment after corrections for (anharmonic) zero-point energy. With the structure in hand, we then explore the mechanical origin of the various band locations using a local electric field formalism. This approach promises to provide a transferrable scheme for the prediction of the OH stretching fundamentals displayed by water networks in close proximity to solute ions.

9.
J Chem Phys ; 145(13): 134304, 2016 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-27782420

RESUMO

We report the isotope-dependent vibrational predissociation spectra of the H2-tagged OH- ⋅ (H2O)n=2,3 clusters, from which we determine the strongly coordination-dependent energies of the fundamentals due to the OH groups bound to the ion and the intramolecular bending modes of the water molecules. The HOH bending fundamental is completely missing in the delocalized OH- ⋅ (H2O) binary complex but is recovered upon adding the second water molecule, thereby establishing that the dihydrate behaves as a hydroxide ion solvated by two essentially intact water molecules. The energies of the observed OH stretches are in good agreement with the values predicted by Takahashi and co-workers [Phys. Chem. Chem. Phys. 17, 25505 (2015); 15, 114 (2013)] with a theoretical model that treats the strong anharmonicities at play in this system with explicit coupling between the bound OH groups and the O-O stretching modes on an extended potential energy surface. We highlight a surprising similarity between the spectral signatures of OH- ⋅ (H2O)3 and the excess proton analogue, H3O+ ⋅ (H2O)3, both of which correspond to completed hydration shells around the proton defect. We discuss the origin of the extreme solvatochromicity displayed by both OH- and H+ in the context of the anomalously large "proton polarizabilities" of the H5O2+ and H3O2- binary complexes.

10.
Phys Chem Chem Phys ; 17(13): 8518-29, 2015 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-25749545

RESUMO

This study explores the interactions underlying the IR spectra of the ionic liquid [NC4111][NTf2] and its deuterated isotopomer [d9-NC4111][NTf2] by first isolating the spectra of charged ionic building blocks using mass-selective CIVP spectroscopy and then following the evolution of these bands upon sequential assembly of the ionic constituents. The spectra of the (1,1) and (2,2) neutral ion pairs are recorded using superfluid helium droplets as well as a solid neon matrix, while those of the larger charged aggregates are again obtained with CIVP. In general, the cluster spectra are similar to that of the bulk, with the (2,2) system displaying the closest resemblance. Analysis of the polarization-dependent band intensities of the neutral ion pairs in liquid droplets as a function of external electric field yields dipole moments of the neutral aggregates. This information allows a coarse assessment of the packing structure of the neutral pairs to be antiparallel at 0.37 K, in contrast to the parallel arrangement found for the assembly of small, high-dipole neutral molecules with large rotational constants (e.g., HCN). The role of an extra anion or cation attached to both the (1,1) and the (2,2) ion pairs to form the charged clusters is discussed in the context of an additional remote, more unfavorable binding site intrinsic to the nature of the charged IL clusters and as such not anticipated in the bulk phase. Whereas for the anion itself only the lowest energy trans conformer was observed, the higher clusters showed an additional population of the cis conformer. The interactions are found to be consistent with a minimal role of hydrogen bonding.

11.
J Phys Chem A ; 119(52): 13018-24, 2015 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-26608571

RESUMO

To understand how the D2d oxalate scaffold (C2O4)(2-) distorts upon capture of a proton, we report the vibrational spectra of the cryogenically cooled HO2CCO2(-) anion and its deuterated isotopologue DO2CCO2(-). The transitions associated with the skeletal vibrations and OH bending modes are sharp and are well described by inclusion of cubic terms in the normal mode expansion of the potential surface through an extended Fermi resonance analysis. The ground state structure features a five-membered ring with an asymmetric intramolecular proton bond. The spectral signatures of the hydrogen stretches, on the contrary, are surprisingly diffuse, and this behavior is not anticipated by the extended Fermi scheme. We trace the diffuse bands to very strong couplings between the high-frequency OH-stretch and the low-frequency COH bends as well as heavy particle skeletal deformations. A simple vibrationally adiabatic model recovers this breadth of oscillator strength as a 0 K analogue of the motional broadening commonly used to explain the diffuse spectra of H-bonded systems at elevated temperatures, but where these displacements arise from the configurations present at the vibrational zero-point level.

12.
J Phys Chem A ; 119(36): 9425-40, 2015 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-26158593

RESUMO

We review the role that gas-phase, size-selected protonated water clusters, H(+)(H2O)n, have played in unraveling the microscopic mechanics responsible for the spectroscopic behavior of the excess proton in bulk water. Because the larger (n ≥ 10) assemblies are formed with three-dimensional cage morphologies that more closely mimic the bulk environment, we report the spectra of cryogenically cooled (10 K) clusters over the size range 2 ≤ n ≤ 28, over which the structures evolve from two-dimensional arrangements to cages at around n = 10. The clusters that feature a complete second solvation shell around a surface-embedded hydronium ion yield spectral signatures of the proton defect similar to those observed in dilute acids. The origins of the large observed shifts in the proton vibrational signature upon cluster growth were explored with two types of theoretical analyses. First, we calculate the cubic and semidiagonal quartic force constants and use these in vibrational perturbation theory calculations to establish the couplings responsible for the large anharmonic red shifts. We then investigate how the extended electronic wave functions that are responsible for the shapes of the potential surfaces depend on the nature of the H-bonded networks surrounding the charge defect. These considerations indicate that, in addition to the sizable anharmonic couplings, the position of the OH stretch most associated with the excess proton can be traced to large increases in the electric fields exerted on the embedded hydronium ion upon formation of the first and second solvation shells. The correlation between the underlying local structure and the observed spectral features is quantified using a model based on Badger's rule as well as via the examination of the electric fields obtained from electronic structure calculations.

13.
J Phys Chem A ; 119(10): 1859-66, 2015 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-25647222

RESUMO

The strong temperature dependence of the I(-)·(H2O)2 vibrational predissociation spectrum is traced to the intracluster dissociation of the ion-bound water dimer into independent water monomers that remain tethered to the ion. The thermodynamics of this process is determined using van't Hoff analysis of key features that quantify the relative populations of H-bonded and independent water molecules. The dissociation enthalpy of the isolated water dimer is thus observed to be reduced by roughly a factor of three upon attachment to the ion. The cause of this reduction is explored with electronic structure calculations of the potential energy profile for dissociation of the dimer, which suggest that both reduction of the intrinsic binding energy and vibrational zero-point effects act to weaken the intermolecular interaction between the water molecules in the first hydration shell. Additional insights are obtained by analyzing how classical trajectories of the I(-)·(H2O)2 system sample the extended potential energy surface with increasing temperature.

14.
J Chem Phys ; 142(6): 064306, 2015 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-25681905

RESUMO

We clarify the role of the critical imidazolium C(2)H position (the central C between N atoms in the heterocycle) in the assembly motif of the [EMIM][BF4] ionic liquid by analyzing the vibrational spectra of the bare EMIM(+) ion as well as that of the cationic [EMIM]2[BF4](+) (EMIM(+) = 1-ethyl-3-methylimidazolium, C6H11N2 (+)) cluster. Vibrational spectra of the cold, mass-selected ions are obtained using cryogenic ion vibrational predissociation of weakly bound D2 molecules formed in a 10 K ion trap. The C(2)H behavior is isolated by following the evolution of key vibrational features when the C(2) hydrogen, the proposed binding location of the anion to the imidazolium ring, is replaced by either deuterium or a methyl group (i.e., in the EMMIM(+) analogue). Strong features in the ring CH stretching region of the bare ion are traced to Fermi resonances with overtones of lower frequency modes. Upon incorporation into the EMIM(+) ⋅ ⋅ ⋅ BF4 (-) ⋅ ⋅ ⋅ EMIM(+) ternary complex, the C(2)H oscillator strength is dramatically increased, accounting for the much more complicated patterns derived from the EMIM(+) ring CH stretches in the light isotopomer, which are strongly suppressed in the deuterated analogue. Further changes in the spectra that occur when the C(2)H is replaced by a methyl group are consistent with BF4 (-) attachment directly to the imidazolium ring in an arrangement that maximizes the electrostatic interaction between the molecular ions.

15.
J Chem Phys ; 143(14): 144305, 2015 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-26472377

RESUMO

The role of proton-assisted charge accommodation in electron capture by a heterocyclic electron scavenger is investigated through theoretical analysis of the vibrational spectra of cold, gas phase [Py ⋅ (H2O)n=3-5](-) clusters. These radical anions are formed when an excess electron is attached to water clusters containing a single pyridine (Py) molecule in a supersonic jet ion source. Under these conditions, the cluster ion distribution starts promptly at n = 3, and the photoelectron spectra, combined with vibrational predissociation spectra of the Ar-tagged anions, establish that for n > 3, these species are best described as hydrated hydroxide ions with the neutral pyridinium radical, PyH((0)), occupying one of the primary solvation sites of the OH(-). The n = 3 cluster appears to be a special case where charge localization on Py and hydroxide is nearly isoenergetic, and the nature of this species is explored with ab initio molecular dynamics calculations of the trajectories that start from metastable arrangements of the anion based on a diffuse, essentially dipole-bound electron. These calculations indicate that the reaction proceeds via a relatively slow rearrangement of the water network to create a favorable hydration configuration around the water molecule that eventually donates a proton to the Py nitrogen atom to yield the product hydroxide ion. The correlation between the degree of excess charge localization and the evolving shape of the water network revealed by this approach thus provides a microscopic picture of the "solvent coordinate" at the heart of a prototypical proton-coupled electron transfer reaction.

16.
Am J Sports Med ; : 3635465231203698, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38288527

RESUMO

BACKGROUND: Patient sex is known to affect patient outcomes in sports medicine. Historically, many studies on athletes have focused on male athletes and been generalized to female athletes. HYPOTHESIS: Studies with female first or senior authors will isolate female athletes as study participants more frequently than studies with male first or senior authors. STUDY DESIGN: Systematic review; Level of evidence, 4. METHODS: Following PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) protocols, original research studies published between 2017 and 2021 that analyzed athletes were systematically screened from the 6 top sports medicine journals (British Journal of Sports Medicine; Arthroscopy: The Journal of Arthroscopic and Related Surgery; Knee Surgery, Sports Traumatology, Arthroscopy; American Journal of Sports Medicine; Orthopaedic Journal of Sports Medicine; Sports Health: A Multidisciplinary Approach). Articles were included for analysis if they met the following criteria: (1) original sports medicine research study, (2) analysis involving athletes, and (3) inclusion of ≥10 participants. Exclusion criteria included (1) review articles of any type and (2) cadaveric studies. The determination of author sex was completed using the name-to-gender assignment algorithm Genderize.io (https://genderize.io/). RESULTS: A total of 1146 studies were included in quantitative analysis. There were 246 studies with a female first author (21.5%) and 191 studies with a female senior author (16.7%). When looking at all authors (first, senior, and intermediate), 19.9% were female. Female first authors were over 4 times more likely to isolate female athletes in clinical research than male first authors (17.5% vs 3.8%, respectively; P < .001). Female senior authors were approximately twice as likely to isolate female athletes compared with male senior authors (11.5% vs 5.8%, respectively; P < .001). CONCLUSION: Female first authors were significantly more likely to perform research isolating female athletes. While improving the frequency of female athlete research is multifactorial, increasing the number of female researchers may have a direct effect on improving gender equality in sports medicine research.

17.
J Chem Phys ; 139(22): 224305, 2013 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-24329066

RESUMO

To clarify the intramolecular distortions exhibited by the complementary ions in the archetypal ionic liquid 1-ethyl-3-methylimidazolium tetrafluoroborate [EMIM][BF4], we report the vibrational spectra of the isolated ionic constituents and small aggregates cooled to about 10 K. Deuteration of bare EMIM(+) at the C(2) position, the putative hydrogen bond donating group, establishes that the observed bulk red shift is too small (<10 cm(-1)) for hydrogen bonding to be a dominant structural feature. We then analyze how the vibrational patterns evolve with increasing size to identify the spectral signatures of well-defined structural motifs in the growing assembly. Surprisingly, the main features of the bulk spectrum are already developed in the cluster with a single BF4 (-) anion sandwiched between just two EMIM(+) cations. We suggest that this local motif, while not strongly hydrogen bonded, nonetheless induces considerable intensity in the C(2)H stretches and is a robust feature in the local molecular structure of the liquid.

18.
Surg Endosc ; 26(7): 1813-21, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22350227

RESUMO

BACKGROUND: Laparoscopic gastrectomy has gained acceptance as treatment for early gastric cancer. However, its role for advanced gastric cancer remains unclear. This study aimed to compare the oncologic outcomes between laparoscopic and open gastrectomy in the management of advanced gastric cancer for patients receiving adjuvant chemoradiotherapy. METHODS: This study reviewed consecutive patients treated with gastric cancer resection and adjuvant chemoradiation (45 Gy/25 with 5-fluorouracil [FU]-based chemotherapy), at a quaternary care comprehensive cancer center between 1 Jan 2000 and 30 Nov 2009. Of 203 patients, 21 were treated with laparoscopic gastrectomy. These patients were compared with patients who had open surgery and evaluated for overall survival, relapse-free survival, and site of first disease recurrence. RESULTS: The 21 patients in the laparoscopic group had a median age of 61.3 years (range, 28.2-76.6 years) and a median follow-up period of 21.3 months (range, 6.7-50.4 months). The majority of the patients (71%) were men. Most of these patients had tumor node metastasis (TNM) v6 stage 2 (33%) or 3 (52%) disease as classified by the American Joint Committee on Cancer (AJCC) and the Union for International Cancer Control (UICC). The demographic characteristics of the laparoscopic and open groups were similar. The incidence of recurrence was 38.1% (8/21) in the laparoscopic group and 36.8% (67/182) in the open group. In the laparoscopic group, the site of first recurrence was distant in three patients, peritoneal in four patients, and mixed in one patient (locoregional and distant). The recurrence patterns did not differ significantly between the laparoscopic and open surgery groups. In the open group, recurrence was distant in 26 patients, peritoneal in 12 patients, and locoregional in 15 patients. At presentation, 14 patients showed a mixed pattern. The 3-year relapse-free survival rate was 58% (range, 50-66%), and the difference between the two groups by Gray's test was not significant (P = 0.32). The 3-year overall survival rate was 65.9% (range, 58-73%) and did not differ significantly between the two groups in the univariate (P = 0.92) or multivariate (P = 0.54) analysis. CONCLUSION: The study findings suggest that laparoscopic gastrectomy is an oncologically safe procedure for advanced gastric cancer with outcomes similar to those for open resection.


Assuntos
Gastrectomia/métodos , Laparoscopia/métodos , Neoplasias Gástricas/terapia , Adulto , Idoso , Antimetabólitos Antineoplásicos/uso terapêutico , Estudos de Casos e Controles , Quimiorradioterapia Adjuvante/métodos , Quimiorradioterapia Adjuvante/mortalidade , Intervalo Livre de Doença , Feminino , Fluoruracila/uso terapêutico , Gastrectomia/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/etiologia , Recidiva Local de Neoplasia/mortalidade , Estudos Retrospectivos , Neoplasias Gástricas/mortalidade , Resultado do Tratamento
19.
Stereotact Funct Neurosurg ; 90(3): 188-91, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22678456

RESUMO

BACKGROUND: We report the first application of Gamma Knife radiosurgery (GKR) for recurrent glossopharyngeal neuralgia (GN) after microvascular decompression (MVD). The patient is a 51-year-old male with left-sided GN. He underwent MVD and did well for almost 4 years. Later on, the patient started to experience recurrent intolerable throat pain, frequently 10/10 in intensity. Based on the application of radiosurgery for trigeminal neuralgia, GKR was offered to the patient. METHODS: After careful identification of the nerve with the assistance of a neuroradiologist, we targeted the nerve root complex, which is the cisternal portion of the nerve, using the Coherent Oscillatory State Acquisition for the Manipulation of Image Contrast (COSMIC) pulse sequence with contiguous 1-mm slices obtained by an 1.5 Tesla MRI. The radiosurgery was planned utilizing the Leksell Gamma Plan version 8.1. A single shot with a 4-mm collimator was used to deliver 80 Gy to the 100% isodose line. RESULTS: Four weeks after the treatment, the patient began to notice significant pain relief. At the 12-month follow-up, the patient's pain, which was intolerable prior to radiosurgery, was mild and occasional. CONCLUSION: GKR, which is now widely used for refractory trigeminal neuralgia, can be considered for refractory or recurrent GN. With a multidisciplinary approach and advanced neuroimaging, GKR is feasible for GN after MVD, despite the shortness of the intracranial cisternal nerve portion. Further studies are necessary to establish the role of GKR for refractory GN after MVD; however, given its rarity and the lack of experience with GKR for this condition, retrospective studies with dozens of patients are almost impossible at this time.


Assuntos
Doenças do Nervo Glossofaríngeo/cirurgia , Cirurgia de Descompressão Microvascular , Radiocirurgia/instrumentação , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Recidiva , Resultado do Tratamento
20.
Methods Cell Biol ; 169: 237-266, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35623704

RESUMO

The study of protein complexes and protein-protein interactions is of great importance due to their fundamental roles in cellular function. Proximity labeling, often coupled with mass spectrometry, has become a powerful and versatile tool for studying protein-protein interactions by enriching and identifying proteins in the vicinity of a specified protein-of-interest. Here, we describe and compare traditional approaches to investigate protein-protein interactions to current day state-of-the-art proximity labeling methods. We focus on the wide array of proximity labeling strategies and underscore studies using diverse model systems to address numerous biological questions. In addition, we highlight current advances in mass spectrometry-based technology that exhibit promise in improving the depth and breadth of the data acquired in proximity labeling experiments. In all, we show the diversity of proximity labeling strategies and emphasize the broad range of applications and biological inquiries that can be addressed using this technology.


Assuntos
Modelos Biológicos , Espectrometria de Massas
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