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1.
Artigo em Inglês | MEDLINE | ID: mdl-38965194

RESUMO

Anticancer systemic therapy comprises a complex and growing group of drugs. Some of the new agents with novel mechanisms of action that have appeared are difficult to fit in the groups of classical chemotherapy, hormones, tyrosine-kinase inhibitors, and monoclonal antibodies. We propose a classification based on two levels of information: the site of action and the mechanism of action. Regarding the former, drugs can exert their action in the tumor cell, the tumor vasculature, the immune system, or the endocrine system. The mechanism of action refers to the molecular target.

2.
Metabolomics ; 19(7): 60, 2023 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-37344702

RESUMO

INTRODUCTION: Breast cancer is the most diagnosed tumor and the leading cause of cancer death in women worldwide. Metabolomics allows the quantification of the entire set of metabolites in blood samples, making it possible to study differential metabolomics patterns related to neoadjuvant treatment in the breast cancer neoadjuvant setting. OBJECTIVES: Characterizing metabolic differences in breast cancer blood samples according to their response to neoadjuvant treatment. METHODS: One hundred and three plasma samples of breast cancer patients, before receiving neoadjuvant treatment, were analyzed through UPLC-MS/MS metabolomics. Then, metabolomics data were analyzed using probabilistic graphical models and biostatistics methods. RESULTS: Metabolomics data allowed the identification of differences between groups according to response to neoadjuvant treatment. These differences were specific to each breast cancer subtype. Patients with HER2+ tumors showed differences in metabolites related to amino acids and carbohydrates pathways between the two pathological response groups. However, patients with triple-negative tumors showed differences in metabolites related to the long-chain fatty acids pathway. Patients with Luminal B tumors showed differences in metabolites related to acylcarnitine pathways. CONCLUSIONS: It is possible to identify differential metabolomics patterns between complete and partial responses to neoadjuvant therapy, being this metabolomic profile specific for each breast cancer subtype.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Terapia Neoadjuvante/efeitos adversos , Cromatografia Líquida , Metabolômica , Espectrometria de Massas em Tandem
3.
Int J Mol Sci ; 24(1)2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36614248

RESUMO

Immunotherapy based on anti-PD1 antibodies has improved the outcome of advanced melanoma. However, prediction of response to immunotherapy remains an unmet need in the field. Tumor PD-L1 expression, mutational burden, gene profiles and microbiome profiles have been proposed as potential markers but are not used in clinical practice. Probabilistic graphical models and classificatory algorithms were used to classify melanoma tumor samples from a TCGA cohort. A cohort of patients with advanced melanoma treated with PD-1 inhibitors was also analyzed. We established that gene expression data can be grouped in two different layers of information: immune and molecular. In the TCGA, the molecular classification provided information on processes such as epidermis development and keratinization, melanogenesis, and extracellular space and membrane. The immune layer classification was able to distinguish between responders and non-responders to immunotherapy in an independent series of patients with advanced melanoma treated with PD-1 inhibitors. We established that the immune information is independent than molecular features of the tumors in melanoma TCGA cohort, and an immune classification of these tumors was established. This immune classification was capable to determine what patients are going to respond to immunotherapy in a new cohort of patients with advanced melanoma treated with PD-1 inhibitors Therefore, this immune signature could be useful to the clinicians to identify those patients who will respond to immunotherapy.


Assuntos
Melanoma , Neoplasias Cutâneas , Humanos , Transcriptoma , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Melanoma/tratamento farmacológico , Melanoma/genética , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/genética , Imunoterapia
4.
Proteomics ; 22(3): e2100110, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34624180

RESUMO

Triple negative breast cancer accounts for 15%-20% of all breast carcinomas and is clinically characterized by an aggressive phenotype and poor prognosis. Triple negative tumors do not benefit from targeted therapies, so further characterization is needed to define subgroups with potential therapeutic value. In this work, the proteomes of 125 formalin-fixed paraffin-embedded samples from patients diagnosed with non-metastatic triple negative breast cancer were analyzed using data-independent acquisition + in a LTQ-Orbitrap Fusion Lumos mass spectrometer coupled to an EASY-nLC 1000. 1206 proteins were identified in at least 66% of the samples. Hierarchical clustering, probabilistic graphical models and Significance Analysis of Microarrays were combined to characterize proteomics-based molecular groups. Two molecular groups were defined with differences in biological processes such as glycolysis, translation and immune response. These two molecular groups showed also several differentially expressed proteins. This clinically homogenous dataset may serve to design new therapeutic strategies in the future.


Assuntos
Neoplasias de Mama Triplo Negativas/metabolismo , Feminino , Formaldeído , Humanos , Inclusão em Parafina , Proteoma/metabolismo , Proteômica , Neoplasias de Mama Triplo Negativas/patologia
5.
Monaldi Arch Chest Dis ; 92(4)2022 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-35179011

RESUMO

Trastuzumab therapy has dramatically changed breast cancer prognosis. Consensus documents recommend a close monitoring during therapy, not always feasible, especially in metastatic breast cancer. The purpose of this study is to describe trastuzumab cardiotoxicity in metastatic breast cancer patients to understand how to improve cardiovascular monitoring. We retrospectively studied metastatic breast cancer patients scheduled for trastuzumab therapy (2001-2018). All patients underwent a baseline evaluation and monitoring during therapy. Cardiotoxicity was defined as symptomatic heart failure or asymptomatic decrease in left ventricular ejection fraction > 10% from baseline and < 53%. Ninety-two women were included, mean age 61 years (±14.43), median follow-up 42.5 months (IQR 26-74). Fourteen percent developed cardiotoxicity:  two heart failure with preserved left ventricular ejection fraction, three heart failure with reduced left ventricular ejection fraction, and eight asymptomatic decreased in left ventricular ejection fraction. Eighty-one percent of cardiac dysfunction cases occurred within the first 4 years and on median of 31 months from trastuzumab initiation. Thus, in metastatic breast cancer patients, trastuzumab-mediated cardiotoxicity occurred more frequently during the first 4 years. These data should be considered to optimize follow-up protocols.


Assuntos
Neoplasias da Mama , Cardiopatias , Insuficiência Cardíaca , Neoplasias da Mama/tratamento farmacológico , Cardiotoxicidade/epidemiologia , Cardiotoxicidade/etiologia , Feminino , Cardiopatias/complicações , Insuficiência Cardíaca/complicações , Humanos , Incidência , Pessoa de Meia-Idade , Receptor ErbB-2 , Estudos Retrospectivos , Volume Sistólico , Trastuzumab/efeitos adversos , Função Ventricular Esquerda
6.
Angew Chem Int Ed Engl ; 61(10): e202116650, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35014139

RESUMO

The successful topochemical polymerization of bis(selenocyanatomethyl)butadyine 1 is achieved upon association in a 1 : 1 co-crystal with 1,2-bis(2-pyridyl)ethylene (2-bpen) through strong and linear (NC)-Se⋅⋅⋅NPy chalcogen bonding (ChB) interactions, allowing for an appropriate parallel alignment of the diacetylene moieties toward the solid-state reaction. Co-crystal 1⋅(2-bpen) undergoes polymerization upon heating at 100 °C. The reaction progress was monitored by IR, DSC and PXRD. An enhancement of the polymer conductivity by 8 orders of magnitude is observed upon iodine doping. Strikingly, the course of polymerization is accompanied with sublimation of the ChB acceptor molecules 2-bpen, providing the polymer in a pure form with full recovery of the co-former, at variance with the usual hydrogen-bonded co-crystal strategies toward polydiacetylenes.

7.
Bioessays ; 41(1): e1800128, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30537007

RESUMO

Despite abundant evidence associating CD38 overexpression and CD4 T cell depletion in HIV infection, no causal relation has been investigated. To address this issue, a series of mechanisms are proposed, supported by evidence from different fields, by which CD38 overexpression can facilitate CD4 T cell depletion in HIV infection. According to this model, increased catalytic activity of CD38 may reduce CD4 T cells' cytoplasmic nicotin-amide adenine dinucleotide (NAD), leading to a chronic Warburg effect. This will reduce mitochondrial function. Simultaneously, CD38's catalytic products ADPR and cADPR may be transported to the cytoplasm, where they can activate calcium channels and increase cytoplasmic Ca2+ concentrations, further altering mitochondrial integrity. These mechanisms will decrease the viability and regenerative capacity of CD4 T cells. These hypotheses can be tested experimentally, and might reveal novel therapeutic targets. Also see the video abstract here https://youtu.be/k1LTyiTKPKs.


Assuntos
ADP-Ribosil Ciclase 1/genética , Regulação da Expressão Gênica , Infecções por HIV/enzimologia , Glicoproteínas de Membrana/genética , ADP-Ribosil Ciclase 1/metabolismo , Progressão da Doença , Infecções por HIV/genética , Humanos , Glicoproteínas de Membrana/metabolismo , Regulação para Cima
8.
Int J Mol Sci ; 22(21)2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34769406

RESUMO

CD38 is a transmembrane glycoprotein expressed by T-cells. It has been reported that patients with systemic lupus erythematosus (SLE) showed increased CD38+CD25+ T-cells correlating with immune activation and clinical signs. Contrariwise, CD38 deficiency in murine models has shown enhanced autoimmunity development. Recent studies have suggested that CD38+ regulatory T-cells are more suppressive than CD38- regulatory T-cells. Thus, we have suggested that CD38 overexpression in SLE patients could play a role in regulating immune activation cells instead of enhancing it. This study found a correlation between CD38 with FoxP3 expression and immunosuppressive molecules (CD69, IL-10, CTLA-4, and PD-1) in T-cells from lupus-prone mice (B6.MRL-Faslpr/J). Additionally, B6.MRL-Faslpr/J mice showed a decreased proportion of CD38+ Treg cells regarding wild-type mice (WT). Furthermore, Regulatory T-Cells (Treg cells) from CD38-/- mice showed impairment in expressing immunosuppressive molecules and proliferation after stimulation through the T-cell receptor (TCR). Finally, we demonstrated an increased ratio of IFN-γ/IL-10 secretion in CD38-/- splenocytes stimulated with anti-CD3 compared with the WT. Altogether, our data suggest that CD38 represents an element in maintaining activated and proliferative Treg cells. Consequently, CD38 could have a crucial role in immune tolerance, preventing SLE development through Treg cells.


Assuntos
ADP-Ribosil Ciclase 1/imunologia , Fatores de Transcrição Forkhead/imunologia , Imunossupressores/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Glicoproteínas de Membrana/imunologia , Linfócitos T Reguladores/imunologia , ADP-Ribosil Ciclase 1/genética , Animais , Autoimunidade , Modelos Animais de Doenças , Fatores de Transcrição Forkhead/genética , Tolerância Imunológica , Lúpus Eritematoso Sistêmico/patologia , Masculino , Glicoproteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
9.
Molecules ; 26(13)2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-34279389

RESUMO

The ability of alkylseleno/alkyltelluroacetylenes such as bis(selenomethylethynyl)-perfluorobenzene (4F-Se) to act as a ditopic chalcogen bond (ChB) donor in co-crystals with ditopic Lewis bases such as 4,4'-bipyridine is extended here to the octafluorobiphenylene analog, 4,4'-bis(selenomethylethynyl)-perfluorobiphenyl (8F-Se), with the more electron-rich 4,4'-bipyridylethane (bpe), showing in the 1:1 (8F-Se)•(bpe) co-crystal a shorter and more linear C-Se•••N ChB interaction than in (4F-Se)•(bpe), with Se•••N distances down to 2.958(2) Šat 150 K, i.e., a reduction ratio of 0.85 vs. the van der Waals contact distance.

10.
Angew Chem Int Ed Engl ; 60(1): 366-370, 2021 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-32926491

RESUMO

Crystal engineering based on σ-hole interactions is an emerging approach for realization of new materials with higher complexity. Neutral inorganic clusters derived from 1,2-dicarba-closo-dodecaborane, substituted with -SeMe, -TeMe, and -I moieties on both skeletal carbon vertices are experimentally demonstrated herein as outstanding chalcogen- and halogen-bond donors. In particular, these new molecules strongly interact with halide anions in the solid-state. The halide ions are coordinated by one or two donor groups (µ1 - and µ2 -coordinations), to stabilize a discrete monomer or dimer motifs to 1D supramolecular zig-zag chains. Crucially, the observed chalcogen bond and halogen bond interactions feature remarkably short distances and high directionality. Electrostatic potential calculations further demonstrate the efficiency of the carborane derivatives, with Vs,max being similar or even superior to that of reference organic halogen-bond donors, such as iodopentafluorobenzene.

11.
Oncologist ; 25(10): e1516-e1524, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32329131

RESUMO

BACKGROUND: Standard oncology tools are inadequate to distinguish which older patients are at higher risk of developing chemotherapy-related complications. MATERIALS AND METHODS: Patients over 70 years of age starting new chemotherapy regimens were prospectively included in a multicenter study. A prechemotherapy assessment that included sociodemographics, tumor/treatment variables, and geriatric assessment variables was performed. Association between these factors and the development of grade 3-5 toxicity was examined by using logistic regression. RESULTS: A total of 551 patients were accrued. Chemotherapy doses (odds ratio [OR] 1.834; 95% confidence interval [CI] 1.237-2.719) and creatinine clearance (OR 0.989; 95% CI 0.981-0.997) were the only factors independently associated with toxicity. Only 19% of patients who received reduced doses of chemotherapy and had a creatinine clearance ≥40 mL/minute had grade 3-4 toxicity, compared with 38% of those who received standard doses or had a creatinine clearance <40 mL/minute (p < .0001). However, no satisfactory multivariate model was obtained using different selection approaches. CONCLUSION: Chemotherapy doses and renal function were identified as the major risk factors for developing severe toxicity in the older patient. These factors should be considered when planning to initiate a new chemotherapy regimen and should also lead to a closer follow-up in these patients. IMPLICATIONS FOR PRACTICE: Older patients are more vulnerable to chemotherapy toxicity. However, standard tools are inadequate to identify who is at higher risk of developing chemotherapy-related complications. Chemotherapy doses (standard vs. reduced) and renal function were identified as the major risk factors for developing severe toxicity in the elderly. These factors should be considered when planning to initiate a new chemotherapy regimen and should also lead to a closer follow-up.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Avaliação Geriátrica , Humanos , Neoplasias/tratamento farmacológico , Estudos Prospectivos
12.
BMC Cancer ; 20(1): 307, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32293335

RESUMO

BACKGROUND: Metabolomics has a great potential in the development of new biomarkers in cancer and it has experiment recent technical advances. METHODS: In this study, metabolomics and gene expression data from 67 localized (stage I to IIIB) breast cancer tumor samples were analyzed, using (1) probabilistic graphical models to define associations using quantitative data without other a priori information; and (2) Flux Balance Analysis and flux activities to characterize differences in metabolic pathways. RESULTS: On the one hand, both analyses highlighted the importance of glutamine in breast cancer. Moreover, cell experiments showed that treating breast cancer cells with drugs targeting glutamine metabolism significantly affects cell viability. On the other hand, these computational methods suggested some hypotheses and have demonstrated their utility in the analysis of metabolomics data and in associating metabolomics with patient's clinical outcome. CONCLUSIONS: Computational analyses applied to metabolomics data suggested that glutamine metabolism is a relevant process in breast cancer. Cell experiments confirmed this hypothesis. In addition, these computational analyses allow associating metabolomics data with patient prognosis.


Assuntos
Neoplasias da Mama/metabolismo , Perfilação da Expressão Gênica/métodos , Glutamina/metabolismo , Redes e Vias Metabólicas , Metabolômica/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Bases de Dados Genéticas , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Células MCF-7 , Redes e Vias Metabólicas/efeitos dos fármacos , Pessoa de Meia-Idade , Modelos Teóricos , Estadiamento de Neoplasias
13.
Angew Chem Int Ed Engl ; 59(52): 23583-23587, 2020 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-32940957

RESUMO

Activation of a deep electron-deficient area on chalcogen atoms (Ch=Se, Te) is demonstrated in alkynyl chalcogen derivatives, in the prolongation of the (C≡)C-Ch bond. The solid-state structures of 1,4-bis(methylselenoethynyl)perfluorobenzene (1Se) show the formation of recurrent chalcogen-bonded (ChB) motifs. Association of 1Se and the tellurium analogue 1Te with 4,4'-bipyridine and with the stronger Lewis base 1,4-di(4-pyridyl)piperazine gives 1:1 co-crystals with 1D extended structures linked by short and directional ChB interactions, comparable to those observed with the corresponding halogen bond (XB) donor, 1,4-bis(iodoethynyl)-perfluorobenzene. This "alkynyl" approach for chalcogen activation provides the crystal-engineering community with efficient, and neutral ChB donors for the elaboration of supramolecular 1D (and potentially 2D or 3D) architectures, with a degree of strength and predictability comparable to that of halogen bonding in iodoacetylene derivatives.

14.
BMC Cancer ; 19(1): 636, 2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-31253132

RESUMO

BACKGROUND: Muscle-invasive bladder tumors are associated with a high risk of relapse and metastasis even after neoadjuvant chemotherapy and radical cystectomy. Therefore, further therapeutic options are needed and molecular characterization of the disease may help to identify new targets. The aim of this study was to characterize muscle-invasive bladder tumors at the molecular level using computational analyses. METHODS: The TCGA cohort of muscle-invasive bladder cancer patients was used to describe these tumors. Probabilistic graphical models, layer analyses based on sparse k-means coupled with Consensus Cluster, and Flux Balance Analysis were applied to characterize muscle-invasive bladder tumors at a functional level. RESULTS: Luminal and Basal groups were identified, and an immune molecular layer with independent value was also described. Luminal tumors showed decreased activity in the nodes of epidermis development and extracellular matrix, and increased activity in the node of steroid metabolism leading to a higher expression of the androgen receptor. This fact points to the androgen receptor as a therapeutic target in this group. Basal tumors were highly proliferative according to Flux Balance Analysis, which makes these tumors good candidates for neoadjuvant chemotherapy. The Immune-high group showed a higher degree of expression of immune biomarkers, suggesting that this group may benefit from immune therapy. CONCLUSIONS: Our approach, based on layer analyses, established a Luminal group candidate for therapy with androgen receptor inhibitors, a proliferative Basal group which seems to be a good candidate for chemotherapy, and an immune-high group candidate for immunotherapy.


Assuntos
Carcinoma de Células de Transição/classificação , Carcinoma de Células de Transição/genética , Neoplasias da Bexiga Urinária/classificação , Neoplasias da Bexiga Urinária/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Carcinoma de Células de Transição/metabolismo , Carcinoma de Células de Transição/terapia , Matriz Extracelular/metabolismo , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Redes e Vias Metabólicas , Pessoa de Meia-Idade , Invasividade Neoplásica , Receptores Androgênicos/genética , Neoplasias da Bexiga Urinária/metabolismo , Neoplasias da Bexiga Urinária/terapia
15.
Chemphyschem ; 20(1): 148-158, 2019 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-30412344

RESUMO

A theoretical study of the effect of the diprotonation on the nucleic acid bases (A : U, A : T and G : C) in Watson-Crick conformation has been carried out by means of DFT computational methods in vacuum. In addition, the corresponding neutral and monoprotonated binary complexes have been considered. Most of the diprotonated species studied are stable, even though the binding energy is positive due to the overall repulsive electrostatic term. Local electrostatic attractive forces in the regions of hydrogen bonds (HBs) are responsible for equilibrium geometries, as shown by the electric field lines connecting the electrophilic and nucleophilic sites involved in the HB interactions. Secondary electrostatic effects also affect the assembling of the nucleic acid complexes in either neutral or cationic form. In particular, the electric field lines flowing from electrophilic sites in one base to nucleophilic sites in the other reinforce the linking between them. Hence, when the nucleophilic site concerns the free lone pair of the heteroatom involved in the HB interaction as acceptor, the HB distance shortens. However, if the free lone pair of the HB acceptor interacts with an electrophilic site in the same molecule, the HB distance elongates, weakening the HB interaction. The topological analysis of the electron density distribution in HB regions indicates that neutral, monoprotonated and diprotonated complexes show no differences in the nature of their HB's.


Assuntos
Modelos Moleculares , Ácidos Nucleicos/química , Pareamento de Bases , Cátions , Ligação de Hidrogênio , Conformação de Ácido Nucleico , Teoria Quântica , Eletricidade Estática , Termodinâmica
16.
Future Oncol ; 15(30): 3483-3490, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31580166

RESUMO

Aim: Differences in metabolism among breast cancer subtypes suggest that metabolism plays an important role in this disease. Flux balance analysis is used to explore these differences as well as drug response. Materials & methods: Proteomics data from breast tumors were obtained by mass-spectrometry. Flux balance analysis was performed to study metabolic networks. Flux activities from metabolic pathways were calculated and used to build prognostic models. Results: Flux activities of vitamin A, tetrahydrobiopterin and ß-alanine metabolism pathways split our population into low- and high-risk patients. Additionally, flux activities of glycolysis and glutamate metabolism split triple negative tumors into low- and high-risk groups. Conclusion: Flux activities summarize flux balance analysis data and can be associated with prognosis in cancer.


Assuntos
Neoplasias da Mama/metabolismo , Biologia Computacional/métodos , Recidiva Local de Neoplasia/metabolismo , Proteoma/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Intervalo Livre de Doença , Feminino , Humanos , Análise do Fluxo Metabólico , Redes e Vias Metabólicas , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/patologia , Prognóstico , Fatores de Risco , Taxa de Sobrevida
17.
J Phys Chem A ; 123(32): 7156-7170, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31294565

RESUMO

Polarizability is a key molecular property involved in either macroscopic (i.e., dielectric constant) and microscopic properties (i.e., interaction energies). In rigid molecules, this property only depends on the ability of the electron density (ED) to acquire electrostatic moments in response to applied electric fields. Databases of transferable electron density fragments are a cheap and efficient way to access molecular EDs. This approach is rooted in the relative conservation of the atomic ED between different molecules, termed transferability principle. The present work discusses the application of this transferability principle to the polarizability, an electron density-derived property, partitioned in atomic contributions using the Quantum Theory of Atoms In Molecules topology. The energetic consequences of accounting for in situ deformation (polarization) of database multipolar atoms are investigated in detail by using a high-quality quantum chemical benchmark.

18.
Chemistry ; 24(43): 10881-10905, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-29488652

RESUMO

Crystallography and quantum mechanics have always been tightly connected because reliable quantum mechanical models are needed to determine crystal structures. Due to this natural synergy, nowadays accurate distributions of electrons in space can be obtained from diffraction and scattering experiments. In the original definition of quantum crystallography (QCr) given by Massa, Karle and Huang, direct extraction of wavefunctions or density matrices from measured intensities of reflections or, conversely, ad hoc quantum mechanical calculations to enhance the accuracy of the crystallographic refinement are implicated. Nevertheless, many other active and emerging research areas involving quantum mechanics and scattering experiments are not covered by the original definition although they enable to observe and explain quantum phenomena as accurately and successfully as the original strategies. Therefore, we give an overview over current research that is related to a broader notion of QCr, and discuss options how QCr can evolve to become a complete and independent domain of natural sciences. The goal of this paper is to initiate discussions around QCr, but not to find a final definition of the field.

19.
J Infect Dis ; 216(1): 82-91, 2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28498953

RESUMO

Increased mortality and morbidity occur among human immunodeficiency virus (HIV)-infected patients in whom CD4+ T-cell counts do not increase despite viral suppression with antiretroviral therapy (ART). Here we identified an underlying mechanism. Significantly elevated plasma levels of anti-CD4 immunoglobulin G (IgG) were found in HIV-positive immunologic nonresponders (ie, HIV-positive individuals with CD4+ T-cell counts of ≤350 cells/µL), compared with levels in HIV-positive immunologic responders (ie, HIV-positive individuals with CD4+ T-cell counts of ≥500 cells/µL) and healthy controls. Higher plasma level of anti-CD4 IgG correlated with blunted CD4+ T-cell recovery. Furthermore, purified anti-CD4 IgG from HIV-positive immunologic nonresponders induced natural killer (NK) cell-dependent CD4+ T-cell cytolysis and apoptosis through antibody-dependent cell-mediated cytotoxicity (ADCC) in vitro. We also found that anti-CD4 IgG-mediated ADCC exerts greater apoptosis of naive CD4+ T cells relative to memory CD4+ T cells. Consistently, increased frequencies of CD107a+ NK cells and profound decreases of naive CD4+ T cells were observed in immunologic nonresponders as compared to responders and healthy controls ex vivo. These data indicate that autoreactive anti-CD4 IgG may play an important role in blunted CD4+ T-cell reconstitution despite effective ART.


Assuntos
Citotoxicidade Celular Dependente de Anticorpos , Terapia Antirretroviral de Alta Atividade , Antígenos CD4/imunologia , Infecções por HIV/imunologia , Imunoglobulina G/sangue , Adulto , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Antivirais/sangue , Antivirais/uso terapêutico , Contagem de Linfócito CD4 , Linfócitos T CD4-Positivos/imunologia , Estudos Transversais , Feminino , HIV , Infecções por HIV/sangue , Infecções por HIV/tratamento farmacológico , Humanos , Imunoglobulina G/imunologia , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/imunologia , Leucócitos Mononucleares/metabolismo , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Análise Multivariada
20.
Oncologist ; 22(11): 1301-1308, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28701571

RESUMO

BACKGROUND: Nanoparticle albumin-bound paclitaxel (nab-Paclitaxel) is an alternative to standard taxanes for breast cancer (BC) treatment. We evaluated nab-Paclitaxel efficacy as neoadjuvant treatment for early estrogen receptor-positive (ER+), human epidermal growth factor receptor 2-negative (HER2-) disease. MATERIALS AND METHODS: Women with ER+, HER2-, stage II-III BC were treated preoperatively with four cycles of weekly nab-Paclitaxel (150 mg/m2), 3 weeks on and 1 week off. We hypothesized that poor pathological response rate (residual cancer burden [RCB] III; Symmans criteria) would be ≤16%. RESULTS: Eighty-one patients with a median age of 47 years were treated; 64.2% were premenopausal, and 69% of tumors were stage II. Residual cancer burden III rate was 28.4% (95% confidence interval [CI]: 18.6%-38.2%), RCB 0+I (good response) rate was 24.7% (95% CI: 15.3%-34.1%) and RCB 0 (complete response) rate was 7.4% (95% CI: 1.7%-13.1%). Objective response rate by magnetic resonance imaging was 76.5% and rate of conversion to breast conserving surgery was 40.0%. The most frequent grade 3 and 4 toxicity was neutropenia (12.3% and 3.7% of patients, respectively), without any febrile neutropenia. Sensory neuropathy grade 2 and 3 were seen in 25.9% and 2.5% of patients, respectively. Tumor secreted protein, acidic, cysteine-rich (SPARC) overexpression was significantly associated with RCB 0 (odds ratio: 0.079; 95% CI: 0.009-0.689; p = .0216). CONCLUSION: Despite failing to confirm an RCB III rate ≤16% in nab-Paclitaxel-treated patients, the RCB 0+I rate indicates a significant drug antitumor activity with low rates of grade 3-4 toxicity. Our exploratory biomarker analysis suggests a potential predictive role of complete response for SPARC. Confirmatory analyses are warranted, adapting dose and schedule to decrease peripheral neurotoxicity. (Trial registration: European Clinical Trials Database study number: 2011-004476-10; ClinicalTrials.gov: NCT01565499). IMPLICATIONS FOR PRACTICE: The pathological response rate (residual cancer burden [RCB]; Symmans criteria) of nanoparticle albumin-bound paclitaxel administered as neoadjuvant treatment for early estrogen receptor-positive, human epidermal growth factor receptor 2-negative disease was evaluated. Whereas poor response (RCB III) was 24.7%, similar to that for docetaxel, good response (RCB 0+I) reached 23.0%, far superior to the 13% for docetaxel, while keeping toxicity low. Exploratory biomarker analysis suggests secreted protein, acidic, cysteine-rich overexpression in tumor cells as a potential predictor of complete response (RCB 0). Findings point to an encouraging single-agent neoadjuvant treatment with low toxicity, which warrants future research and development.


Assuntos
Paclitaxel Ligado a Albumina/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Nanopartículas/administração & dosagem , Adulto , Idoso , Paclitaxel Ligado a Albumina/química , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia , Receptor alfa de Estrogênio/genética , Feminino , Humanos , Pessoa de Meia-Idade , Nanopartículas/química , Receptor ErbB-2/genética
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