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1.
Clin Radiol ; 77(8): 570-576, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35595563

RESUMO

AIM: To evaluate the prognostic value of the hypoperfusion intensity ratio (HIR) on 90-day clinical outcome in acute ischaemic stroke (AIS) patients with late therapeutic window. MATERIALS AND METHODS: One hundred and sixty-eight consecutive AIS patients with anterior-circulation large-vessel occlusion who underwent endovascular thrombectomy during the late window were enrolled retrospectively. Clinical data, Alberta Stroke Program Early Computed Tomography Score (ASPECTS) based on unenhanced computed tomography (CT), and perfusion parameters included ischaemic core, hypoperfusion volume, mismatch volume between core and penumbra, and the HIR were assessed and compared between patients with or without favourable outcomes (defined as modified Rankin Scale score of 0-2). Statistical analysis included binary logistic regression and receiver operating characteristic (ROC) analyses. RESULTS: A favourable outcome was achieved in 76 (45.2%) patients. In univariable analysis, age, National Institutes of Health Stroke Scale (NIHSS) score at admission, ASPECTS score, HIR, ischaemic core, and hypoperfusion volume were significantly associated with functional outcome (p<0.05). In multivariate analyses, age (OR 0.95; 95% CI 0.92-0.99), NIHSS score at admission (OR 0.89, 95% CI 0.84-0.96) and HIR (OR 0.018, 95% CI 0.003-0.113) remained as independent outcome predictors (p<0.01). The optimal threshold of HIR was 0.36 (sensitivity 70.7%, specificity 61.8%). The combination of age, NIHSS score at admission, and HIR yield good performance for outcome prediction with an area under the ROC curve of 0.815 (sensitivity 88.2%, specificity 64.1%), significantly higher than individual variable (p<0.05). CONCLUSION: Low HIR was a predictor for favourable outcome in AIS patients with late therapeutic window. Integrating HIR with clinical variables improved the ability for outcome classification.


Assuntos
Isquemia Encefálica , Procedimentos Endovasculares , AVC Isquêmico , Acidente Vascular Cerebral , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/cirurgia , Humanos , AVC Isquêmico/diagnóstico por imagem , AVC Isquêmico/cirurgia , Estudos Retrospectivos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/cirurgia , Trombectomia/métodos , Resultado do Tratamento
2.
Mol Psychiatry ; 21(11): 1537-1544, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-26809842

RESUMO

Dyslipidemia is one of the most common adverse effects in schizophrenia patients treated with antipsychotics. However, there are no established effective treatments. In this study, data were pooled from two randomized, placebo-controlled trials, which were originally designed to examine the efficacy of metformin in treating antipsychotic-induced weight gain and other metabolic abnormalities. In total, 201 schizophrenia patients with dyslipidemia after being treated with an antipsychotic were assigned to take 1000 mg day-1 metformin (n=103) or placebo (n=98) for 24 weeks, with evaluation at baseline, week 12 and week 24. The primary outcome was the low-density lipoprotein cholesterol (LDL-C) levels. After metformin treatment, the mean difference in the LDL-C value between metformin treatment and placebo was from 0.16 mmol l-1 at baseline to -0.86 mmol l-1 at the end of week 24, decreased by 1.02 mmol l-1 (P<0.0001); and 25.3% of patients in the metformin group had LDL-C ≥3.37 mmol l-1, which is significantly <64.8% in the placebo group (P<0.001) at week 24. Compared with the placebo, metformin treatment also have a significant effect on reducing weight, body mass index, insulin, insulin resistance index, total cholesterol and triglyceride, and increasing high-density lipoprotein cholesterol. The treatment effects on weight and insulin resistance appeared at week 12 and further improved at week 24, but the effects on improving dyslipidemia only significantly occurred at the end of week 24. We found that metformin treatment was effective in improving antipsychotic-induced dyslipidemia and insulin resistance, and the effects improving antipsychotic-induced insulin resistance appeared earlier than the reducing dyslipidemia.


Assuntos
Dislipidemias/tratamento farmacológico , Metformina/farmacologia , Metformina/uso terapêutico , Adulto , Antipsicóticos/uso terapêutico , Glicemia , Peso Corporal/efeitos dos fármacos , Método Duplo-Cego , Feminino , Humanos , Hipoglicemiantes/uso terapêutico , Insulina , Resistência à Insulina , Lipoproteínas LDL/análise , Lipoproteínas LDL/sangue , Masculino , Obesidade/tratamento farmacológico , Esquizofrenia/complicações , Esquizofrenia/tratamento farmacológico , Aumento de Peso/efeitos dos fármacos
3.
Phys Chem Chem Phys ; 19(45): 30351-30361, 2017 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-29099122

RESUMO

The gas-phase conformations of the protonated forms of thymidine-5'-monophosphate and uridine-5'-monophosphate, [pdThd+H]+ and [pUrd+H]+, are investigated by infrared multiple photon dissociation (IRMPD) action spectroscopy and electronic structure calculations. The IRMPD action spectra of [pdThd+H]+ and [pUrd+H]+ are measured over the IR fingerprint and hydrogen-stretching regions using the FELIX free electron laser and an OPO/OPA laser system. Low-energy conformations of [pdThd+H]+ and [pUrd+H]+ and their relative stabilities are computed at the MP2(full)/6-311+G(2d,2p)//B3LYP/6-311+G(d,p) and B3LYP/6-311+G(2d,2p)//B3LYP/6-311+G(d,p) levels of theory. Comparisons of the measured IRMPD action spectra and B3LYP/6-311+G(d,p) linear IR spectra computed for the low-energy conformers indicate that the dominant conformers of [pdThd+H]+ and [pUrd+H]+ populated in the experiments are protonated at the phosphate oxo oxygen atom, with a syn nucleobase orientation that is stabilized by strong P[double bond, length as m-dash]OH+O2 and P-OHO4' hydrogen-bonding interactions, and C2'-endo sugar puckering. Minor abundance of conformers protonated at the O2 carbonyl of the nucleobase residue may also contribute for [pdThd+H]+, but do not appear to be important for [pUrd+H]+. Comparisons to previous IRMPD spectroscopy investigations of the protonated forms of thymidine and uridine, [dThd+H]+ and [Urd+H]+, and the deprotonated forms of pdThd and pUrd, [pdThd-H]- and [pUrd-H]-, provide insight into the effects of the phosphate moiety and protonation on the conformational features of the nucleobase and sugar moieties. Most interestingly, the thymine and uracil nucleobases remain in their canonical forms for [pdThd+H]+ and [pUrd+H]+, unlike [dThd+H]+ and [Urd+H]+, where protonation occurs on the nucleobases and induces tautomerization of the thymine and uracil residues.


Assuntos
Monoéster Fosfórico Hidrolases/química , Timidina Monofosfato/química , Timina/química , Uracila/química , Ligação de Hidrogênio , Conformação Molecular , Fosfatos , Espectrofotometria Infravermelho , Uridina/química
4.
Phys Chem Chem Phys ; 18(23): 16021-32, 2016 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-27240654

RESUMO

Our previous gas-phase infrared multiple photon dissociation action spectroscopy study of protonated 2'-deoxyadenosine and adenosine, [dAdo+H](+) and [Ado+H](+), found that both N3 and N1 protonated conformers are populated with the N3 protonated ground-state conformers predominant in the experiments. Therefore, N-glycosidic bond dissociation mechanisms of N3 and N1 protonated [dAdo+H](+) and [Ado+H](+) and the associated quantitative thermochemical values are investigated here using both experimental and theoretical approaches. Threshold collision-induced dissociation (TCID) of [dAdo+H](+) and [Ado+H](+) with Xe is studied using guided ion beam tandem mass spectrometry techniques. For both systems, N-glycosidic bond cleavage reactions are observed as the major dissociation pathways resulting in production of protonated adenine or elimination of neutral adenine. Electronic structure calculations are performed at the B3LYP/6-311+G(d,p) level of theory to probe the potential energy surfaces (PESs) for N-glycosidic bond cleavage of [dAdo+H](+) and [Ado+H](+). Relative energetics of the reactants, transition states, intermediates and products along the PESs for N-glycosidic bond cleavage are determined at the B3LYP/6-311+G(2d,2p), B3LYP-GD3BJ/6-311+G(2d,2p), and MP2(full)/6-311+G(2d,2p) levels of theory. The predicted N-glycosidic bond dissociation mechanisms for the N3 and N1 protonated species differ. Base rotation of the adenine residue enables formation of a strong N3H(+)O5' hydrogen-bonding interaction that stabilizes the N3 protonated species and its glycosidic bond. Comparison between experiment and theory indicates that the N3 protonated species determine the threshold energies, as excellent agreement between the measured and B3LYP computed activation energies (AEs) and reaction enthalpies (ΔHrxns) for N-glycosidic bond cleavage of the N3 protonated species is found.

5.
Phys Chem Chem Phys ; 18(35): 24451-9, 2016 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-27536972

RESUMO

The gas-phase conformations of protonated uridine, [Urd+H](+), and its 2'-deoxy form, protonated 2'-deoxyuridine, [dUrd+H](+), have been examined in detail previously by infrared multiple photon dissociation action spectroscopy techniques. Both 2,4-dihydroxy tautomers and O4 protonated conformers of [Urd+H](+) and [dUrd+H](+) were found to coexist in the experiments with the 2,4-dihydroxy tautomers dominating the population. In the present study, the kinetic energy dependence of the collision-induced dissociation behavior of [Urd+H](+) and [dUrd+H](+) are examined using a guided ion beam tandem mass spectrometer to probe the mechanisms and energetics for activated dissociation of these protonated nucleosides. The primary dissociation pathways observed involve N-glycosidic bond cleavage leading to competitive elimination of protonated or neutral uracil. The potential energy surfaces (PESs) for these N-glycosidic bond cleavage pathways are mapped out via electronic structure calculations for the mixture of 2,4-dihydroxy tautomers and O4 protonated conformers of [Urd+H](+) and [dUrd+H](+) populated in the experiments. The calculated activation energies (AEs) and heats of reaction (ΔHrxns) for N-glycosidic bond cleavage at both the B3LYP and MP2(full) levels of theory are compared to the measured values. The agreement between experiment and theory indicates that B3LYP provides better estimates of the energetics of the species along the PESs for N-glycosidic bond cleavage than MP2, and that the 2,4-dihydroxy tautomers, which are stabilized by strong hydrogen-bonding interactions, predominantly influence the observed threshold dissociation behavior of [Urd+H](+) and [dUrd+H](+).

6.
Phys Chem Chem Phys ; 18(4): 2968-80, 2016 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-26740232

RESUMO

Experimental and theoretical investigations suggest that hydrolysis of N-glycosidic bonds generally involves a concerted SN2 or a stepwise SN1 mechanism. While theoretical investigations have provided estimates for the intrinsic activation energies associated with N-glycosidic bond cleavage reactions, experimental measurements to validate the theoretical studies remain elusive. Here we report experimental investigations for N-glycosidic bond cleavage of the protonated guanine nucleosides, [dGuo+H](+) and [Guo+H](+), using threshold collision-induced dissociation (TCID) techniques. Two major dissociation pathways involving N-glycosidic bond cleavage, resulting in production of protonated guanine or the elimination of neutral guanine are observed in competition for both [dGuo+H](+) and [Guo+H](+). The detailed mechanistic pathways for the N-glycosidic bond cleavage reactions observed are mapped via electronic structure calculations. Excellent agreement between the measured and B3LYP calculated activation energies and reaction enthalpies for N-glycosidic bond cleavage of [dGuo+H](+) and [Guo+H](+) in the gas phase is found indicating that these dissociation pathways involve stepwise E1 mechanisms in analogy to the SN1 mechanisms that occur in the condensed phase. In contrast, MP2 is found to significantly overestimate the activation energies and slightly overestimate the reaction enthalpies. The 2'-hydroxyl substituent is found to stabilize the N-glycosidic bond such that [Guo+H](+) requires ∼25 kJ mol(-1) more than [dGuo+H](+) to activate the glycosidic bond.


Assuntos
Desoxiguanosina/química , Glicosídeos/química , Guanosina/química , Hidrólise , Prótons
7.
Phys Chem Chem Phys ; 18(22): 15081-90, 2016 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-27197049

RESUMO

Infrared multiple photon dissociation (IRMPD) action spectra of the protonated forms of 2'-deoxyguanosine-5'-monophosphate and guanosine-5'-monophosphate, [pdGuo+H](+) and [pGuo+H](+), are measured over the IR fingerprint and hydrogen-stretching regions using the FELIX free electron laser and an OPO/OPA laser system. Electronic structure calculations are performed to generate low-energy conformations of [pdGuo+H](+) and [pGuo+H](+) and determine their relative stabilities at the B3LYP/6-311+G(2d,2p)//B3LYP/6-311+G(d,p) and MP2(full)/6-311+G(2d,2p)//B3LYP/6-311+G(d,p) levels of theory. Comparative analyses of the measured IRMPD action spectra and B3LYP/6-311+G(d,p) linear IR spectra computed for the low-energy conformers are performed to determine the most favorable site of protonation and the conformers present in the experiments. These comparisons and the computed energetics find that N7 protonation is considerably preferred over O6 and N3, and the N7 protonated ground-state conformers of [pdGuo+H](+) and [pGuo+H](+) are populated in the experiments. The 2'-hydroxyl substituent does not significantly impact the stable low-energy conformers of [pdGuo+H](+)vs. those of [pGuo+H](+). The effect of the 2'-hydroxyl substituent is primarily reflected in the relative intensities of the measured IRMPD bands, as the IRMPD profiles of [pdGuo+H](+) and [pGuo+H](+) are quite similar. Comparisons to previous IRMPD spectroscopy investigations of the protonated forms of the guanine nucleosides, [dGuo+H](+) and [Guo+H](+), and deprotonated forms of the guanine nucleotides, [pdGuo-H](-) and [pGuo-H](-), provide insight into the effects of the phosphate moiety and protonation on the conformational features of the nucleobase and sugar moieties. Protonation is found to induce base rotation of the guanine residue to an anti orientation vs. the syn orientation found for the deprotonated forms of the guanine nucleotides.


Assuntos
Nucleotídeos de Desoxiguanina/química , Guanosina Monofosfato/química , Prótons , Modelos Moleculares , Conformação Molecular , Espectrofotometria Infravermelho/métodos , Termodinâmica
8.
Genet Mol Res ; 15(3)2016 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-27706775

RESUMO

Human colorectal cancer (CRC) is a major worldwide health concern, and its development has been shown to be associated with alcohol intake. We carried out a study to investigate the effect of the ADH1B Arg47His and ALDH2 Glu487Lys genetic polymorphisms and their interaction with alcohol consumption on development of CRC. Between March 2013 and May 2015, a total of 274 CRC patients and 358 healthy controls were recruited. Genotyping of sequence variations was performed using the polymerase chain reaction-restriction fragment length polymorphism method. Under a co-dominant model, individuals with the ADH1B Arg47His AA genotype showed increased CRC risk compared to those carrying the GG genotype, with an adjusted odds ratio (and 95% confidence interval) of 3.37 (2.00-5.70). Moreover, under dominant and recessive models, ADH1B Arg47His variant genotypes were associated with greater susceptibility to CRC when compared with the wild-type sequence. Both polymorphisms examined were positively associated with alcohol consumption in a Spearman correlation analysis of CRC risk. In conclusion, our study suggests that the ADH1B Arg47His polymorphism, but not the ALDH2 Glu487Lys variation, may influence development of CRC in the Chinese population.


Assuntos
Álcool Desidrogenase/genética , Aldeído-Desidrogenase Mitocondrial/genética , Povo Asiático/genética , Neoplasias Colorretais/genética , Interação Gene-Ambiente , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único/genética , Estudos de Casos e Controles , Demografia , Feminino , Estudos de Associação Genética , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
9.
Genet Mol Res ; 15(4)2016 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-28081275

RESUMO

Non-small cell lung cancer (NSCLC) is the most common cancer globally. The XRCC1 protein interacts with ligase and poly(ADP-ribose) polymerase to repair cisplatin-induced DNA damage. The authors of previous studies have reported XRCC1 Arg399Gln, Arg280His, and Arg194Trp polymorphisms and advanced NSCLC prognosis, but the results are inconclusive. We investigated the association between clinical outcome and XRCC1 Arg399Gln, Arg280His, and Arg194Trp polymorphisms in advanced NSCLC patients treated with cisplatin. We recruited 252 patients with advanced NSCLC (TNM stages: IIIB and IV) and used polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) to genotype the polymorphisms. Patients with the TT genotype of XRCC1 Arg194Trp showed a significantly better response to chemotherapy than those with the CC genotype. The GA+AA genotype of Arg194Trp was correlated with better response to chemotherapy than the wild-type form. The TT genotype of Arg194Trp was associated with longer survival time than the CC genotype. The TT genotype of Arg194Trp was correlated with lower risk of death from all causes than the CC genotype. The Arg194Trp polymorphisms interacted with squamous cell carcinoma and affected overall survival of advanced NSCLC. However, there was no association between Arg399Gln and Arg280His polymorphisms and response to cisplatin-based chemotherapy and overall survival in advanced NSCLC. The results suggest that the TT genotype of Arg194Trp is significantly associated with better response to chemotherapy and longer overall survival of advanced NSCLC patients than the wild-type form. Our investigation offers insight into the influence of XRCC1 gene polymorphisms on the treatment outcome of advanced NSCLC.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Proteínas de Ligação a DNA/genética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Polimorfismo Genético , Alelos , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/patologia , Cisplatino/administração & dosagem , Genótipo , Humanos , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Estadiamento de Neoplasias , Resultado do Tratamento , Proteína 1 Complementadora Cruzada de Reparo de Raio-X
10.
Phys Chem Chem Phys ; 17(39): 25978-88, 2015 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-26225730

RESUMO

The gas-phase conformations of protonated uridine, [Urd+H](+), and its modified form, protonated 2'-deoxyuridine, [dUrd+H](+), generated by electrospray ionization are investigated using infrared multiple photon dissociation (IRMPD) action spectroscopy techniques. IRMPD action spectra of [Urd+H](+) and [dUrd+H](+) are measured over the IR fingerprint and hydrogen-stretching regions. [Urd+H](+) and [dUrd+H](+) exhibit very similar IRMPD spectral profiles. However, the IRMPD yields of [Urd+H](+) exceed those of [dUrd+H](+) in both the IR fingerprint and hydrogen-stretching regions. The measured spectra are compared to the linear IR spectra predicted for the stable low-energy structures of these species computed at the B3LYP/6-311+G(d,p) level of theory to determine the tautomeric conformations populated by electrospray ionization. Both B3LYP and MP2 methods find O4 and O2 protonated canonical as well as 2,4-dihydroxy tautomers among the stable low-energy structures of [Urd+H](+) and [dUrd+H](+). Comparison between the measured IRMPD and calculated linear IR spectra suggests that these species exist in their ring-closed forms and that both 2,4-dihydroxy tautomers as well as O4 protonated canonical conformers coexist in the population generated by electrospray ionization for both [Urd+H](+) and [dUrd+H](+). The 2'-deoxy modification of [dUrd+H](+) reduces the variety of 2,4-dihydroxy tautomers populated in the experiments vs. those of [Urd+H](+).


Assuntos
Desoxiuridina/química , Prótons , Uridina/química , Gases/química , Isomerismo , Modelos Moleculares , Conformação Molecular , Espectrofotometria Infravermelho
11.
Clin Exp Obstet Gynecol ; 42(3): 315-20, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26152001

RESUMO

OBJECTIVES: To explore whether sex hormone-binding globulin (SHBG) and free androgen index (FAI) can be seen as therapeutic effect indexes of women with polycystic ovarian syndrome (PCOS). MATERIALS AND METHODS: The body mass index (BMI), basal sexual hormones, SHBG, fasting blood glucose (FBG), and fasting insulin (FINS) were collected from 579 women with PCOS, were divided into two groups according to BMI: obese group (n = 145) and non-obese group (n = 434), according to homeostasis model assessment of insulin status (HOMA-IR). Patients were then divided into four groups: A: non-obese without insulin resistance (n = 174), B: non-obese with insulin resistance (n = 260), C: obese without insulin resistance (n = 34), D: obese with insulin resistance (n = 111). A and B groups received Diane-35 alone, C and D groups received Diane-35 plus metformin for three months. Then clomiphene citrate and HMAG were used to induce ovulation then compared ovulation rate and pregnancy outcome. RESULTS: FAI decreased significantly and SHBG increased significantly in all groups. In A group FINS and HOMA-IR increased significantly (p < 0.05), but in B and D groups FINS and HOMA-IR decreased significantly (p < 0.05). After treatment the ovulation rate in non-obese group was higher than obese group (p < 0.01). Compared with non-ovulation patients, SHBG increased significantly and FAI decreased significantly in the patient with ovulation. Regarding the pregnancy outcome, FAI decreased significantly in delivery patients than spontaneous abortion patients. Furthermore, SHBG increased significantly. CONCLUSION: It was important to check SHBG and FAI during the treatment of PCOS patient. They could be used to assess whether the treatment was effective and as a guidance of clinical medication.


Assuntos
Antagonistas de Androgênios/uso terapêutico , Glicemia/metabolismo , Acetato de Ciproterona/uso terapêutico , Etinilestradiol/uso terapêutico , Hipoglicemiantes/uso terapêutico , Insulina/sangue , Metformina/uso terapêutico , Síndrome do Ovário Policístico/tratamento farmacológico , Globulina de Ligação a Hormônio Sexual/metabolismo , Aborto Espontâneo , Adulto , Índice de Massa Corporal , Clomifeno/uso terapêutico , Combinação de Medicamentos , Quimioterapia Combinada , Estradiol/sangue , Feminino , Fármacos para a Fertilidade Feminina/uso terapêutico , Hormônio Foliculoestimulante/sangue , Humanos , Resistência à Insulina , Nascido Vivo , Hormônio Luteinizante/sangue , Obesidade/complicações , Obesidade/metabolismo , Indução da Ovulação/métodos , Síndrome do Ovário Policístico/complicações , Síndrome do Ovário Policístico/metabolismo , Prolactina/sangue , Testosterona/sangue , Resultado do Tratamento , Adulto Jovem
12.
Anal Chem ; 85(22): 11000-6, 2013 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-24117448

RESUMO

Base-pairing interactions in proton-bound dimers of cytosine (C(+)·C) are the major forces responsible for stabilization of DNA i-motif conformations. Permethylation of cytosine in extended (CCG)·(CGG)n trinucleotide repeats has been shown to cause fragile-X syndrome, the most widespread inherited cause of mental retardation in humans. Oligonucleotides containing 5-bromo- or 5-fluorocytosine can bind to proteins that selectively bind methylated DNA, suggesting that halogenated cytosine damage products can potentially mimic methylation signals. However, the influence of methylation or halogenation on the base-pairing energies (BPEs) of proton-bound dimers of cytosine and their impact on the stability of DNA i-motif conformations is presently unknown. To address this, proton-bound homodimers of cytosine and 5-methyl-, 5-fluoro-, 5-bromo-, and 5-iodocytosine are investigated in detail both experimentally and theoretically. The BPEs of proton-bound homodimers of cytosine and the modified cytosines are measured by threshold collision-induced dissociation (TCID) techniques. 5-Methylation of cytosine is found to increase the BPE and would therefore tend to stabilize DNA i-motif conformations. In contrast, 5-halogenation lowers the BPE. However, the BPEs of the proton-bound 5-halocytosine homodimers examined here still significantly exceed that of Watson-Crick G·C base pairs, such that DNA i-motif conformations should be preserved in the presence of these modifications. Excellent agreement between TCID measured and B3LYP calculated BPEs is found, suggesting that B3LYP calculations can be used to provide reliable energetic predictions for related systems.


Assuntos
Pareamento de Bases , Citosina/análogos & derivados , DNA/química , Prótons , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos , Íons , Modelos Teóricos , Conformação de Ácido Nucleico , Motivos de Nucleotídeos
13.
AJNR Am J Neuroradiol ; 44(1): 33-39, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36549850

RESUMO

BACKGROUND AND PURPOSE: Net water uptake is qualified as an imaging marker of brain edema. We aimed to investigate the ability of net water uptake to predict 90-day functional outcome in patients with acute ischemic stroke and large-vessel occlusion. MATERIALS AND METHODS: A total of 295 consecutive patients were retrospectively enrolled. Automated ASPECTS-net water uptake was calculated on the admission CT. The relationship between ASPECTS-net water uptake and 90-day neurologic outcome was assessed. The independent predictors of favorable outcome (mRS score ≤2) were assessed using multivariate logistic regression analysis and receiver operating characteristic curves and stratified by the ASPECTS. RESULTS: Favorable 90-day outcomes were observed in 156 (52.9%) patients. ASPECTS-net water uptake (OR, 0.79; 95% CI, 0.70-0.90), NIHSS scores (OR, 0.91; 95% CI, 0.87-0.96), age (OR, 0.96; 95% CI, 0.94-0.99), and vessel recanalization (OR, 7.78; 95% CI, 3.96-15.29) were independently associated with favorable outcomes at 90 days (all, P < .01). A lower ASPECTS-net water uptake independently predicted a good prognosis, even in the subgroup of patients with low ASPECTS (≤5) (P < .05). An outcome-prediction model based on these variables yielded an area under the receiver operating characteristic curve of 0.856 (95% CI, 0.814-0.899; sensitivity, 76.3%; specificity, 81.3%). CONCLUSIONS: ASPECTS-net water uptake could independently predict 90-day neurologic outcomes in patients with acute ischemic stroke and large-vessel occlusion. Integrating ASPECTS-net water uptake with clinical models could improve the efficiency of outcome stratification.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , AVC Isquêmico/diagnóstico por imagem , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/patologia , Prognóstico , Estudos Retrospectivos , Resultado do Tratamento , Água , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/patologia , Biomarcadores
14.
Pharmacopsychiatry ; 45(5): 177-81, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22290206

RESUMO

INTRODUCTION: Although some previous studies have compared the 2 medicines, ziprasidone and olanzapine most selected chronic patients as subjects. Therefore, the present study was designed to compare the efficacy and safety of ziprasidone vs. olanzapine in naive first-episode schizophrenia. METHODS: 80 patients were randomly assigned to a 6-week treatment either with 80-160 mg/day of ziprasidone or 10-20 mg/day of olanzapine. The primary efficacy measurements were the Positive and Negative Syndrome Scale and Clinical Global Impression-severity scale scores. The second efficacy measurement was the response rate of treatment. Tolerability assessments were also performed. RESULTS: 79 patients completed the trial. The average dose was 127.5 mg/day with ziprasidone and 19.1 mg/day with olanzapine. No significant differences were found between the 2 groups in primary or secondary efficacy measurements at each visit point (all p>0.05). Body weight significantly increased with olanzapine, and more extrapyramidal symptoms were observed with ziprasidone (all p<0.05). Both medicines were well tolerated, and no serious adverse events were observed. CONCLUSION: Ziprasidone was as effective as olanzapine in short-term treatment for first-episode schizophrenia, and both medicines were well tolerated.


Assuntos
Benzodiazepinas , Piperazinas , Transtornos Psicóticos/tratamento farmacológico , Esquizofrenia/tratamento farmacológico , Tiazóis , Adulto , Antipsicóticos/administração & dosagem , Antipsicóticos/efeitos adversos , Doenças dos Gânglios da Base/induzido quimicamente , Benzodiazepinas/administração & dosagem , Benzodiazepinas/efeitos adversos , Pesquisa Comparativa da Efetividade , Relação Dose-Resposta a Droga , Monitoramento de Medicamentos , Cuidado Periódico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Olanzapina , Piperazinas/administração & dosagem , Piperazinas/efeitos adversos , Escalas de Graduação Psiquiátrica , Transtornos Psicóticos/etiologia , Esquizofrenia/complicações , Psicologia do Esquizofrênico , Tiazóis/administração & dosagem , Tiazóis/efeitos adversos , Fatores de Tempo , Resultado do Tratamento , Aumento de Peso/efeitos dos fármacos
15.
J Cell Biol ; 136(2): 433-44, 1997 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-9015313

RESUMO

Basement membranes contain several proteoglycans, and those bearing heparan sulfate glycosaminoglycans such as perlecan and agrin usually predominate. Most mammalian basement membranes also contain chondroitin sulfate, and a core protein, bamacan, has been partially characterized. We have now obtained cDNA clones encoding the entire bamacan core protein of Mr = 138 kD, which reveal a five domain, head-rod-tail configuration. The head and tail are potentially globular, while the central large rod probably forms coiled-coil structures, with one large central and several very short interruptions. This molecular architecture is novel for an extracellular matrix molecule, but it resembles that of a group of intracellular proteins, including some proposed to stabilize the mitotic chromosome scaffold. We have previously proposed a similar stabilizing role for bamacan in the basement membrane matrix. The protein sequence has low overall homology, apart from very small NH2- and COOH-terminal motifs. At the junctions between the distal globular domains and the coiled-coil regions lie glycosylation sites, with up to three N-linked oligosaccharides and probably three chondroitin chains. Three other Ser-Gly dipeptides are unfavorable for substitution. Fusion protein antibodies stained basement membranes in a pattern commensurate with bamacan, and they also Western blotted bamacan core protein from rat L2 cell cultures. The antibodies could also specifically immunoprecipitate an in vitro transcription/translation product from a full-length bamacan cDNA. The unusual structure of this proteoglycan is indicative of specific functional roles in basement membrane physiology, commensurate with its distinct expression in development and changes in disease models.


Assuntos
Membrana Basal/química , Proteínas de Ciclo Celular , Proteoglicanas de Sulfatos de Condroitina/química , Proteínas Cromossômicas não Histona , Glicoproteínas de Membrana/química , Sequência de Aminoácidos , Animais , Sequência de Bases , Northern Blotting , Células COS , Proteoglicanas de Sulfatos de Condroitina/genética , Sulfatos de Condroitina/química , Clonagem Molecular , DNA Complementar/genética , Dipeptídeos/química , Glicosilação , Glicoproteínas de Membrana/genética , Dados de Sequência Molecular , Peso Molecular , Biossíntese de Proteínas , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Ratos , Proteínas Recombinantes de Fusão/química , Homologia de Sequência de Aminoácidos , Transcrição Gênica , Transfecção
16.
Eur Rev Med Pharmacol Sci ; 23(21): 9464-9470, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31773684

RESUMO

OBJECTIVE: The aim of this study was to explore the role of microRNA-579-3p (miR-579-3p) in the development of squamous cell lung carcinoma (SCLC). Our findings might provide new insights into the treatment of SCLC. PATIENTS AND METHODS: Quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) was performed to examine the expression level of miR-579-3p in 30 pairs of CRC tissues and para-cancerous tissues. The relation between miR-579-3p expression and clinical features of SCLC patients was analyzed. MiR-579-3p expression in SCLC cells was further verified by qRT-PCR as well. In addition, the effects of miR-579-3p on the migration and invasion of SK-MES-1 cells were examined through the transwell assay. RESULTS: QRT-PCR results revealed for the first time that miR-579-3p was significantly down-regulated in SCLC tissues. This indicated that miR-579-3p was possibly involved in the development of SCLC. According to bioinformatics prediction websites and the luciferase activity assay, macrophage scavenger receptor 1 (MSR1) was predicted and verified as the target gene of miR-579-3p. Transfection of miR-579-3p mimics significantly reduced the protein expression level of MSR1 in cells, eventually inhibiting the proliferation, invasion, and migration of SCLC cells. CONCLUSIONS: The miR-579-3p/MSR1 axis might be a novel regulatory pathway of apoptosis, which could be used as potential therapeutic sites in SCLC.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Neoplasias Pulmonares/metabolismo , MicroRNAs/metabolismo , Apoptose , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Linhagem Celular , Movimento Celular , Proliferação de Células , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , MicroRNAs/genética
17.
J Am Soc Mass Spectrom ; 30(9): 1758-1767, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31286444

RESUMO

Gas-phase conformations of the sodium-cationized forms of the 2'-deoxycytidine and cytidine mononucleotides, [pdCyd+Na]+ and [pCyd+Na]+, are examined by infrared multiple photon dissociation action spectroscopy. Complimentary electronic structure calculations at the B3LYP/6-311+G(2d,2p)//B3LYP/6-311+G(d,p) level of theory provide candidate conformations and their respective predicted IR spectra for comparison across the IR fingerprint and hydrogen-stretching regions. Comparisons of the predicted IR spectra and the measured infrared multiple photon dissociation action spectra provide insight into the impact of sodium cationization on intrinsic mononucleotide structure. Further, comparison of present results with those reported for the sodium-cationized cytidine nucleoside analogues elucidates the impact of the phosphate moiety on gas-phase structure. Across the neutral, protonated, and sodium-cationized cytidine mononucleotides, a preference for stabilization of the phosphate moiety and nucleobase orientation is observed, although the details of this stabilization differ with the state of cationization. Several low-energy conformations of [pdCyd+Na]+ and [pCyd+Na]+ involving several different orientations of the phosphate moiety and sugar puckering modes are observed experimentally.


Assuntos
Citidina/química , DNA/química , RNA/química , Sódio/química , Espectrofotometria Infravermelho/métodos , Cátions Monovalentes/química , Monofosfato de Citidina/química , Desoxicitidina Monofosfato/química , Gases/química , Conformação de Ácido Nucleico
18.
J Am Soc Mass Spectrom ; 29(12): 2341-2359, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30159675

RESUMO

Deamidation of asparagine residues, one of the fastest known post-translational modifications in proteins, plays a significant role in various biological functions and degenerative, aging diseases. Here, we present a full description of deamidation (as well as other key dissociation processes) from protonated asparaginyl-alanine, H+(AsnAla), by studying its kinetic energy-dependent threshold collision-induced dissociation (TCID) with Xe using a guided ion beam tandem mass spectrometer. Relative thresholds compare favorably with those acquired by sustained off-resonance irradiation-CID of H+(AsnAla) with Ar in a Fourier transform ion cyclotron resonance mass spectrometer. Absolute threshold energies from the TCID studies are compared to relative single point energies of major reaction species calculated at the B3LYP, B3LYP-GD3BJ, B3P86, MP2(full), and M06-2X levels of theory. Relative energies of key TSs and products allow for the characterization of the important rate-limiting steps involved in H+(AsnAla) decomposition. The influence of water solvation on key TSs is also explored computationally, where bridging the gap between gas-phase and solvated studies is an important aspect of the biological relevance of this analysis. The comprehensive results presented (in addition to complementary studies discussed herein) allow for an insightful comparison to previous deamidation studies such that effects of the C-terminal residue side chain can be elucidated. Graphical abstract ᅟ.


Assuntos
Alanina/química , Asparagina/química , Espectrometria de Massas em Tandem/métodos , Modelos Moleculares , Proteínas/química , Prótons , Termodinâmica
19.
J Clin Invest ; 92(1): 155-9, 1993 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8325980

RESUMO

Aldose reductase (AR) is implicated in the pathogenesis of the diabetic complications and osmotic cataract. AR has been identified as an osmoregulatory protein, at least in the renal medulla. An outstanding question relates to the response of AR gene expression to diet-induced galactosemia in extrarenal tissues. This paper shows that AR gene expression in different tissues is regulated by a complex multifactorial mechanism. Galactose feeding in the rat is associated with a complex and, on occasions, multiphasic pattern of changes in AR mRNA levels in kidney, testis, skeletal muscle, and brain. These changes are not in synchrony with the temporal sequence of changes in tissue galactitol, galactose, and myoinositol concentrations. Moreover, galactose feeding results in changes in tissue AR activities that are not related, temporally or quantitatively, to the alterations in tissue AR mRNA or galactitol levels. It is concluded that AR gene expression and tissue AR activities are regulated by mechanisms that are not purely dependent on nonspecific alterations in intracellular metabolite concentrations. This conclusion is supported by the finding that chronic xylose feeding, despite being associated with intracellular xylitol accumulation, does not result in alterations in AR mRNA levels, at least in the kidney.


Assuntos
Aldeído Redutase/genética , Galactose/metabolismo , Animais , Encéfalo/metabolismo , Galactitol/metabolismo , Expressão Gênica , Inositol/metabolismo , Rim/metabolismo , Masculino , Músculos/metabolismo , RNA Mensageiro/genética , Ratos , Ratos Wistar , Testículo/metabolismo , Xilitol/metabolismo , Xilose/metabolismo
20.
J Am Soc Mass Spectrom ; 28(8): 1638-1646, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28497356

RESUMO

The gas-phase conformations of the protonated forms of the DNA and RNA cytosine mononucleotides, [pdCyd+H]+ and [pCyd+H]+, are examined by infrared multiple photon dissociation (IRMPD) action spectroscopy over the IR fingerprint and hydrogen-stretching regions complemented by electronic structure calculations. The low-energy conformations of [pdCyd+H]+ and [pCyd+H]+ and their relative stabilities are computed at the B3LYP/6-311+G(2d,2p)//B3LYP/6-311+G(d,p) and MP2(full)/6-311+G(2d,2p)//B3LYP/6-311+G(d,p) levels of theory. Comparisons of the measured IRMPD action spectra and B3LYP/6-311+G(d,p) linear IR spectra computed for the low-energy conformers allow the conformers present in the experiments to be determined. Similar to that found in previous IRMPD action spectroscopy studies of the protonated forms of the cytosine nucleosides, [dCyd+H]+ and [Cyd+H]+, both N3 and O2 protonated cytosine mononucleotides exhibiting an anti orientation of cytosine are found to coexist in the experimental population. The 2'-hydroxyl substituent does not significantly influence the most stable conformations of [pCyd+H]+ versus those of [pdCyd+H]+, as the IRMPD spectral profiles of [pdCyd+H]+ and [pCyd+H]+ are similar. However, the presence of the 2'-hydroxyl substituent does influence the relative intensities of the measured IRMPD bands. Comparisons to IRMPD spectroscopy studies of the deprotonated forms of the cytosine mononucleotides, [pdCyd-H]- and [pCyd-H]-, provide insight into the effects of protonation versus deprotonation on the conformational features of the nucleobase and sugar moieties. Likewise, comparisons to results of IRMPD spectroscopy studies of the protonated cytosine nucleosides provide insight into the influence of the phosphate moiety on structure. Comparison with previous ion mobility results shows the superiority of IRMPD spectroscopy for distinguishing various protonation sites. Graphical Abstract ᅟ.


Assuntos
Nucleotídeos de Citosina/química , Prótons , Espectrofotometria Infravermelho , Citosina/química , Gases/química , Modelos Moleculares , Conformação Molecular , Nitrogênio/química , Oxigênio/química , Fótons , Espectrofotometria Infravermelho/métodos
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