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1.
Medicine (Baltimore) ; 102(31): e34477, 2023 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-37543802

RESUMEN

Genetic factors play a crucial role in the immune response of juvenile idiopathic arthritis (JIA) and juvenile-onset systemic lupus erythematosus (JSLE). This study aimed to investigate the association of IL12B (rs3212227, rs6887695) and IL17 (rs2275913, rs763780) gene polymorphisms with the susceptibility of JIA and JSLE in Chinese children. A total of 303 healthy controls and 304 patients including 160 JIA and 144 patients were analyzed, and the genetic polymorphisms were genotyped by using a Sequenom MassArray system. There was a significant association between the IL12B rs3212227 genotype and the increased risk of JSLE (P = .01). For rs6887695, the minor allele C was significantly associated with the increased risk of JIA (odds ratio = 1.48, 95% confidence interval [CI] = 1.12-1.95, P = .005). Moreover, rs6887695 genotype was significantly associated with both JIA and JSLE susceptibility (P < .05). Besides, IL12B haplotype GC significantly associated with the increased risk of JIA (P = .016). However, no significant difference was found between the IL17 (rs2275913, rs763780) gene polymorphisms and JIA or JSLE susceptibility (P > .05). And similar genotype distributions of IL12B and IL17 polymorphisms were found between the patients with nephritis and without nephritis in JSLE (P > .05). Our results indicated that IL12B polymorphisms was associated with an increased risk for the development of JIA and JSLE in Chinese children, highlighting the involvement of inflammation in the pathogenesis of JIA and JSLE. Moreover, there was a risk haplotype in IL12B which could increase the risk of JIA.


Asunto(s)
Artritis Juvenil , Subunidad p40 de la Interleucina-12 , Interleucina-17 , Lupus Eritematoso Sistémico , Niño , Humanos , Artritis Juvenil/genética , Estudios de Casos y Controles , Pueblos del Este de Asia , Predisposición Genética a la Enfermedad , Subunidad p40 de la Interleucina-12/genética , Lupus Eritematoso Sistémico/genética , Nefritis , Polimorfismo de Nucleótido Simple , Interleucina-17/genética
2.
Clin Lab ; 69(8)2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37560848

RESUMEN

BACKGROUND: Children with target lesions are frequently diagnosed with erythema multiforme (EM). EM was not previously thought to be associated with any specific autoimmune serological abnormality. METHODS: We report the case of a 7-year-old girl who developed rashes all over her body with target shaped lesions. Based on clinical appearance and medical history, she was diagnosed with severe erythema multiforme and treated with methylprednisolone. Relevant laboratory tests were performed at admission. RESULTS: At the height of her infection, the antinuclear antibody (ANA) test showed a positive ANA with a titer of 1:100 (speckled pattern) and positive anti-SSA and anti-Ro-52 antibodies. Then she was adjusted for medication. After a week, the infection was relieved, and the re-examination was negative for ANA, anti-SSA, and anti-Ro-52 antibodies. CONCLUSIONS: In previously reported EM cases, ANA is generally not considered to be present. The disappearance of ANA during the convalescent phase suggests that ANA is expressed during the acute phase of EM infection. Its correlation with infection severity warrants further research on the mechanism of autoantibody formation in EM.


Asunto(s)
Anticuerpos Antinucleares , Eritema Multiforme , Humanos , Niño , Femenino , Enfermedad Aguda , Autoanticuerpos , Eritema Multiforme/diagnóstico
3.
Medicine (Baltimore) ; 101(50): e31598, 2022 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-36550815

RESUMEN

BACKGROUND: Juvenile systemic lupus erythematosus (JSLE) and juvenile idiopathic arthritis (JIA) are two common types of autoimmune diseases in children with unclear pathogenesis. Both peptidyl arginine deiminase type IV (PADI4) and interleukin 33 (IL-33) are the key molecular involved in immune responses in autoimmune diseases. Usually, it may share the same risk genetic alleles for autoimmune diseases. METHODS: So measurement of PADI4 and IL-33 polymorphisms was conducted with 303 healthy controls, 144 JSLE patients and 160 JIA patients in this study. RESULTS: It demonstrated that there was a significant association between PADI4 genotypes (rs2240340: CT, CT + CC), IL-33 genotype (rs1929992: TT) and JSLE susceptibility in Southwest China population. While no significant association with the risk of JIA were observed no matter at allelic or genotypic levels. CONCLUSIONS: Our study reveals the importance of PADI4 and IL-33 polymorphisms with JSLE risk and their roles in the development of the diseases need more further researches.


Asunto(s)
Artritis Juvenil , Lupus Eritematoso Sistémico , Humanos , Niño , Artritis Juvenil/genética , Arginina Deiminasa Proteína-Tipo 4/genética , Predisposición Genética a la Enfermedad/genética , Pueblos del Este de Asia , Interleucina-33/genética , Polimorfismo de Nucleótido Simple , Lupus Eritematoso Sistémico/genética , Genotipo , Estudios de Casos y Controles
4.
Ophthalmol Retina ; 6(5): 398-410, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-34999015

RESUMEN

PURPOSE: To validate the generalizability of a deep learning system (DLS) that detects diabetic macular edema (DME) from 2-dimensional color fundus photographs (CFP), for which the reference standard for retinal thickness and fluid presence is derived from 3-dimensional OCT. DESIGN: Retrospective validation of a DLS across international datasets. PARTICIPANTS: Paired CFP and OCT of patients from diabetic retinopathy (DR) screening programs or retina clinics. The DLS was developed using data sets from Thailand, the United Kingdom, and the United States and validated using 3060 unique eyes from 1582 patients across screening populations in Australia, India, and Thailand. The DLS was separately validated in 698 eyes from 537 screened patients in the United Kingdom with mild DR and suspicion of DME based on CFP. METHODS: The DLS was trained using DME labels from OCT. The presence of DME was based on retinal thickening or intraretinal fluid. The DLS's performance was compared with expert grades of maculopathy and to a previous proof-of-concept version of the DLS. We further simulated the integration of the current DLS into an algorithm trained to detect DR from CFP. MAIN OUTCOME MEASURES: The superiority of specificity and noninferiority of sensitivity of the DLS for the detection of center-involving DME, using device-specific thresholds, compared with experts. RESULTS: The primary analysis in a combined data set spanning Australia, India, and Thailand showed the DLS had 80% specificity and 81% sensitivity, compared with expert graders, who had 59% specificity and 70% sensitivity. Relative to human experts, the DLS had significantly higher specificity (P = 0.008) and noninferior sensitivity (P < 0.001). In the data set from the United Kingdom, the DLS had a specificity of 80% (P < 0.001 for specificity of >50%) and a sensitivity of 100% (P = 0.02 for sensitivity of > 90%). CONCLUSIONS: The DLS can generalize to multiple international populations with an accuracy exceeding that of experts. The clinical value of this DLS to reduce false-positive referrals, thus decreasing the burden on specialist eye care, warrants a prospective evaluation.


Asunto(s)
Aprendizaje Profundo , Diabetes Mellitus , Retinopatía Diabética , Edema Macular , Retinopatía Diabética/complicaciones , Retinopatía Diabética/diagnóstico , Humanos , Edema Macular/diagnóstico , Edema Macular/etiología , Estudios Retrospectivos , Tomografía de Coherencia Óptica/métodos , Estados Unidos
5.
Pharmazie ; 76(12): 574-578, 2021 12 05.
Artículo en Inglés | MEDLINE | ID: mdl-34986951

RESUMEN

Development of tyrosine kinase inhibitors (TKIs) achieved great success in the treatment of chronic phase chronic myeloid leukemia (CML). However, patients with CML still relapse without taking TKIs and cases in the accelerated phase or aggressive blast crisis rarely achieved deep response to TKIs. Drug resistance and persistence of leukemia stem cell (LSC) remain great challenges. BCR-ABL kinase dependent or independent mechanism of action are still far from being understood. To achieve a stable deep molecular response and treatment-free remission, finding new targets, eliminating LSC, reducing recurrence and improving prognosis are problems urgently to be solved. It is revealed that tumor microenvironment is crucial for survival, invasion and metastasis of tumor cells. As an adhesion molecule, CD44, a single-chain transmembrane glycoprotein, is not only being identified as a marker for cancer stem cells, but also plays a crucial role in microenvironmental communication and transmitting intracellular signaling for cell proliferation, differentiation, migration, and contributes to tumorigenesis. In this review, we focus on current data relevant to CD44, and outline CD44 structure, the regulation of CD44, functional properties of CD44 in survival, resistance, CML stem cells as well as the potential CD44-targeting therapy for CML management.


Asunto(s)
Leucemia Mielógena Crónica BCR-ABL Positiva , Leucemia Mieloide Aguda , Crisis Blástica/tratamiento farmacológico , Crisis Blástica/metabolismo , Crisis Blástica/patología , Enfermedad Crónica , Resistencia a Antineoplásicos , Humanos , Receptores de Hialuranos/metabolismo , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Leucemia Mielógena Crónica BCR-ABL Positiva/metabolismo , Leucemia Mielógena Crónica BCR-ABL Positiva/patología , Leucemia Mieloide Aguda/tratamiento farmacológico , Células Madre Neoplásicas , Inhibidores de Proteínas Quinasas/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Microambiente Tumoral
6.
Sci Rep ; 8(1): 9442, 2018 06 21.
Artículo en Inglés | MEDLINE | ID: mdl-29930297

RESUMEN

Systemic lupus erythematosus (SLE) has heterogeneous clinical manifestations. IFIH1 (interferon induced with helicase C domain 1) as one of antiviral helicase genes mediating type I interferon production, plays an essential role in the pathogenesis of SLE. The gene variants in IFIH1 could abnormally activate antiviral defenses and increased type I interferon signaling. The present study aimed to validate associations between single nucleotide polymorphisms (SNP) in IFIH1 and the pathogenesis of SLE. In total, rs1990760, rs3747517 and rs10930046 in IFIH1 are genotyped in 400 SLE patients and 659 health controls in Chinese cohort by an improved multiplex ligation detection reaction (iMLDR) technique. Significant associations were observed between alleles of IFIH1 (rs1990760 C > T, P = 0.005, OR = 1.36, 95%CI = 1.10-1.69; rs3747517 T > C, P = 0.004, OR = 1.31, 95%CI = 1.09-1.58, respectively) and SLE susceptibility. IFIH1 rs1990760 TT genotype carriers had lower serum levels of IL-18 (P < 0.001) and granzyme B (P < 0.001) than CC and CT genotype carriers. IFIH1 rs1990760 CT genotype carriers had higher anti-dsDNA-positive than CC and TT genotype carriers. In conclusion, IFIH1 polymorphisms (rs1990760 and rs3747517) were associated with SLE susceptibility and rs1990760 risk T allele related with IL-18 and granzyme B serum levels in SLE patients.


Asunto(s)
Helicasa Inducida por Interferón IFIH1/genética , Interleucina-18/sangre , Lupus Eritematoso Sistémico/genética , Polimorfismo de Nucleótido Simple , Adulto , China , Femenino , Granzimas/sangre , Humanos , Lupus Eritematoso Sistémico/sangre , Masculino , Persona de Mediana Edad
7.
Front Aging Neurosci ; 10: 34, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29535624

RESUMEN

Background: A molecular biomarker of physiologic age, as opposed to chronologic age, is needed in clinical medicine. 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodGsn) and 8-oxo-7, 8-dihydroguanosine (8-oxoGsn) are two promising aging biomarkers. Methods: A total of 1,228 healthy Chinese residents (613 males and 615 females) 2-90 years of age were randomly selected. Spot urine samples were collected, and the concentrations of 8-oxodGsn and 8-oxoGsn were measured using ultra-high-performance liquid chromatography with a triple quadrupole mass spectrometer (UPLC-MS/MS). Method validation, including accuracy, precision, linearity and quantification limit, was performed. The relationship between oxidized guanosine and age/gender was evaluated. Results: 8-oxodGsn and 8-oxoGsn were eluted at 1.61 and 1.30 min, respectively. The calibration curve was linear in the range of 0.2-500 ng/ml for both analytes. The lowest limit of quantification (LLOQ) was 0.2 ng/ml for 8-oxodGsn and 0.1 ng/ml for 8-oxoGsn. There was an age-dependent increase in the biomarkers from the 21- to 30-year-old group to the 81- to 90-year-old group in both genders. In the subjects older than 61 years of age, the levels of 8-oxodGsn as well as 8-oxoGsn in urine were much higher in females than in males. The content of 8-oxoGsn correlated more closely with age and was higher (approximately 2-fold) than that of 8-oxodGsn for a given individual. Conclusions: 8-oxodGsn and 8-oxoGsn can be easily measured by UPLC-MS/MS. Urinary 8-oxoGsn may be a potential biomarker to determine a person's physiologic age and identify individuals at high risk of developing age-associated disease.

8.
Oncotarget ; 9(6): 7066-7074, 2018 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-29467950

RESUMEN

IgA nephropathy (IgAN) is the most common chronic glomerular disease worldwide. Genetic factors are thought to be crucial in the pathogenesis of IgAN. However, few data are available on the relationship between human leucocyte antigen (HLA) and signal transducer and activator of transcription 4 (STAT4) polymorphisms and IgAN susceptibility in the Chinese population. Therefore, we examined HLA-DP/DQ and STAT4 polymorphisms (rs3077, rs9277535, rs7453920 and rs7574865) in a total of 630 subjects including 140 IgAN and 490 healthy controls in Chinese. There were significant associations between IgAN patients and healthy controls in the allele frequency of rs3077, rs9277535 and rs7574865. In addition, the genotypes of rs3077, rs9277535 and rs7574865 were also significantly associated with IgAN under recessive models. Moreover, the haplotypes block AAG, AGG, GAG and GGA in the HLA gene significantly correlated with the risk of IgAN. This is the first study demonstrating the significant associations of SNP rs3077, rs9277535 and rs7574865 and the haplotypes in the HLA gene with the risk of IgAN in a Southwest Chinese population. This research provides a new insight into the significant relationship between HLA-DP and STAT4 polymorphisms and the susceptibility to IgAN.

9.
Oncotarget ; 8(41): 70310-70316, 2017 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-29050281

RESUMEN

The association between the IL-23R and IL-17A polymorphisms and ankylosing spondylitis (AS) in the Southwest Chinese Population is still unclear. The purpose of this study is to detect the association between IL-23R and IL-17A polymorphisms and AS. A case-control study consisting of 486 AS patients and 480 healthy controls was performed. We used the high-resolution melting methods (HRM) to genotype five selected single nucleotide polymorphisms (SNPs), rs6693831, rs7517847, rs1884444, rs10889677 in the IL-23R gene and rs2275913 in the IL-17A gene. Meanwhile, the laboratory indexes were recorded. In this study, patients with genotype CC (p = 8.574E-8) and allele C (p = 3.206E-31) on SNP rs6693831 (IL-23R) showed decreased risk of AS. The genotype TT (p = 4.551E-6) and allele T (p = 0.02) on SNP rs1884444 (IL-23R) showed significant lower risk of AS. Individuals carrying the allele A of rs2275913 showed higher morbidity of AS (p = 0.04). We first detected that rs6693831 and rs1884444 in IL-23R gene and rs2275913 in IL-17A gene have genetic association with AS.

11.
Int Immunopharmacol ; 39: 10-15, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27394003

RESUMEN

Ankylosing spondylitis (AS) is a highly heritable complex inflammatory arthritis disease. Genetic factors are thought to be crucial in the pathogenesis of AS. However, few data are available on the relationship between HLA-DP/DQ and STAT4 polymorphisms and AS susceptibility in the Chinese population. Therefore, we examined HLA-DP/DQ and STAT4 polymorphisms (rs3077, rs9277535, rs7453920 and rs7574865) in a total of 779 subjects, including 400 AS and 379 age- and sex-matched healthy controls in Chinese. No significant difference was observed between AS patients and healthy controls in the allele frequency of rs3077, rs9277535 and rs7574865. However, there was a significant association between the HLA-DQ rs7453920 G/A variant and AS patients, with minor allele A correlated with a reduced risk of AS (allelic frequency, adjusted OR=0.66, 95% CI=0.55-0.78, p=4.0E-06; dominant model, adjusted OR=0.75, 95% CI=0.66-0.85, p=1.1E-05). Moreover, the haplotypes block AAA and GGA in the HLA gene significantly correlated with reduced risk of AS. This is the first study demonstrating the significant associations of SNP rs7453920 and the haplotypes in the HLA gene with the risk of AS in Southwest Chinese population. This research sheds new light on the significant relationship between HLA polymorphisms and AS.


Asunto(s)
Antígenos HLA-DP/genética , Antígenos HLA-DQ/genética , Polimorfismo de Nucleótido Simple , Factor de Transcripción STAT4/genética , Espondilitis Anquilosante/genética , Adulto , China , Femenino , Frecuencia de los Genes , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Masculino , Persona de Mediana Edad
12.
PLoS One ; 11(5): e0155345, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27183113

RESUMEN

BACKGROUND: Currently, the pathogenesis of rheumatoid arthritis (RA) is not clearly understood. The LIGHT/HVEM/BTLA co-signaling pathway may be involved in the pathogenesis of RA, although reports on the expression levels of LIGHT, HVEM and BTLA in T lymphocytes from RA patients are limited. METHOD: In this study, we recruited 30 healthy controls and 21 RA patients. Clinical characteristics were collected for RA patients. The levels of LIGHT, HVEM and BTLA expressed on the surface of circulating T cells of RA patients and healthy controls were measured by flow cytometry. RESULT: The percentages of CD3+, CD4+ and CD8+ T lymphocytes that expressed BTLA from RA patients were all higher than those of the controls (all p < 0.05), while the percentages of CD3+, CD4+ and CD8+ T lymphocytes that expressed HVEM and LIGHT were all lower than those of the controls (all p < 0.05). The rheumatoid factor and the percentage of HVEM+CD4+ T lymphocytes showed a statistically significant negative correlation in RA patients (r = -0.453, p = 0.039), as did the swollen joint count and the percentage of BTLA+CD8+ T lymphocytes (r = -0.501, p = 0.021). CONCLUSION: Here, we provide the first report on the increased expression of BTLA in T lymphocytes and on the decreased expression of HVEM and LIGHT in RA patients. BTLA, HVEM and LIGHT might be involved in the pathogenesis of RA and have the potential to be new clinically useful characteristics of RA.

13.
Oxid Med Cell Longev ; 2016: 4323198, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26770653

RESUMEN

The mechanisms underlying progression of type 2 diabetes are complex and varied. Recent studies indicated that oxidative stress provided a new sight. To further assess the relationship between nucleic acid oxidation and complications in patients with type 2 diabetes and explore its possible molecular mechanisms, we studied 1316 subjects, including 633 type 2 diabetes patients and 683 age- and sex-matched healthy controls. Urinary levels of DNA oxidation marker 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodGuo) and RNA oxidation marker 8-oxo-7,8-dihydroguanosine (8-oxoGuo) were measured by ultraperformance liquid chromatography and mass spectrometry (UPLC-MS/MS). Serum glucose, HbA1c, total cholesterol, HDL cholesterol, LDL cholesterol, and triglycerides (TG) were also determined. The results showed significantly elevated levels of both the urinary 8-oxodGuo and 8-oxoGuo in diabetes patients with/without complications compared with age-matched healthy control subjects (p = 0.02 and p < 0.001, resp.). Patients with complications, especially macrovascular complications, exhibited higher levels of 8-oxoGuo than those without complications, while there was no difference in the concentrations of serum glucose and lipids. The finding indicates the role for oxidative damage to DNA and RNA, as a molecular mechanism contributing to the progression of type 2 diabetes. Elevated levels of 8-oxoGuo may be a risk factor for type 2 diabetes complications, especially in diabetic macrovascular complications.


Asunto(s)
Daño del ADN , ADN/orina , Complicaciones de la Diabetes/orina , Diabetes Mellitus Tipo 2/orina , ARN/orina , 8-Hidroxi-2'-Desoxicoguanosina , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores/orina , Estudios de Casos y Controles , Demografía , Desoxiguanosina/análogos & derivados , Desoxiguanosina/orina , Femenino , Guanosina/análogos & derivados , Guanosina/orina , Humanos , Masculino , Persona de Mediana Edad , Oxidación-Reducción
14.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 47(4): 551-555, 2016 Jul.
Artículo en Chino | MEDLINE | ID: mdl-28591960

RESUMEN

OBJECTIVES: To explore the diagnostic value of immunofixation electrophoresis and Kappa/Lambda (KAP/LAM) ratio in multiple myeloma patients with renal injury. METHODS: The serum of 822 patients of renal disease were collected for the examnation of immunofixation electrophoresis, KAP/LAM ratio, serum immunoglobulin levels and renal function, including serum urea nitrogen (BUN), serum creatinine (Crea), cystatin C (Cys-C) and estimated glomerular filtration rate (eGFR). To analyze the diagnostic value of immunofixation and KAP/LAM ratio in the differentiation of renal injury of multiple myeloma from primary renal injury diseases. RESULTS: M protein was observed in 75 patients (9.1%). The ratio of each type was IgG 49.3%(37/75), IgA 34.7%(26/75), IgM 5.3%(4/75) and LAM 10.7%(8/75). There was significant difference of KAP/LAM ratio between M protein group and non-M protein group. The KAP/LAM ratio was significant higher in KAP group, compared to non-M protein group. Reverse result was obtained in LAM group. There were higher Crea level and lower eGFR value in pure LAM light chain group, compared with IgG, IgA and IgM groups. CONCLUSIONS: Immunofixation electrophoresis and KAP/LAM ratio may play an important role in the diagnosis of multiple myeloma patients with renal injury, so could be early screening markers.


Asunto(s)
Electroforesis , Cadenas Ligeras de Inmunoglobulina/análisis , Cadenas kappa de Inmunoglobulina/análisis , Mieloma Múltiple/diagnóstico , Nitrógeno de la Urea Sanguínea , Creatinina/sangre , Cistatina C/sangre , Tasa de Filtración Glomerular , Humanos
15.
J Phys Chem A ; 119(2): 253-62, 2015 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-25336192

RESUMEN

We show for a series of six small donor-acceptor dyads that the energy difference between non-charge transfer (non-CT) and charge transfer (CT) excited states, as well as the squares of the electronic couplings between these states, can be predicted from first-principles using variational orbital adapted configuration interaction singles (VOA-CIS) theory. VOA-CIS correctly predicts the observed experimental trends in these values and provides quantitative accuracy roughly on par with a modern long-range corrected density functional, ωB97X. Using VOA-CIS and ωB97X, the experimental energy difference between the non-CT and CT excited states is predicted with root mean squared errors of 0.22 eV and 0.21 eV, respectively. The square of the electronic coupling between these states is predicted with root mean squared errors of 0.08 eV(2) and 0.07 eV(2), respectively. Orbital optimized CIS (OO-CIS) and CIS(D), two perturbative corrections to CIS, provide a significant correction to the errant relative energies predicted by CIS, but the correction is insufficient to recover the experimentally observed trend.

16.
J Chem Theory Comput ; 10(3): 1004-20, 2014 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-26580179

RESUMEN

For chemically accurate excited state energies, one is forced to include electron-electron correlation at a level of theory significantly higher than configuration interaction singles (CIS). Post-CIS corrections do exist, but most often, if they are computationally inexpensive, these methods rely on perturbation theory. At the same time, inexpensive variational post-CIS methods would be ideal since modeling electronic relaxation usually requires globally smooth potential energy surfaces (PESs) and there will inevitably be regions of near electronic degeneracy. With that goal in mind, we now present a new method entitled variationally orbital adapted CIS (VOA-CIS). On the one hand, we show that in the ground-state geometry, VOA-CIS performs comparably to CIS(D) at predicting relative excited state energies. On the other hand, far beyond CIS(D) or any other perturbative method, VOA-CIS correctly rebalances the energy of charge-transfer (CT) states versus non-CT states, while simultaneously producing smooth PESs-including the important case of avoided crossings. In fact, through localized diabatization of VOA-CIS excited states, one can find a set of reasonable diabatic states modeling CT chemical dynamics. After significant benchmarking, we are now confident VOA-CIS and VOA-CIS-like methods should play a major role in future excited state calculations.

18.
J Chem Phys ; 138(22): 221105, 2013 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-23781776

RESUMEN

Configuration interaction singles (CIS) describe excited electronic states only qualitatively and improvements are imperative as a means of recovering chemical accuracy. In particular, variational improvements would be ideal to account for state crossings and electronic relaxation. To accomplish such an objective, in this communication we present a new suite of algorithms, abbreviated VOO-CIS for variationally orbital optimized CIS. We show below that VOO-CIS yields a uniform improvement to CIS, rebalancing the energies of CT states versus non-CT states within the same framework. Furthermore, VOO-CIS finds energetic corrections for CT states that are even larger than those predicted by CIS(D). The computational cost of VOO-CIS depends strongly on the number of excited states requested (n), but otherwise should be proportional to the cost of CIS itself.

19.
J Chem Phys ; 136(16): 161101, 2012 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-22559462

RESUMEN

In a recent article, we showed that configuration interaction singles (CIS) has a systematic bias against charge-transfer (CT) states: CT vertical excitation energies are consistently too high (by 1-2 eV) as compared with non-CT energies [J. E. Subotnik, J. Chem. Phys. 137, 071104 (2011)]. We now show that this CIS error can be corrected approximately by performing a single Newton-Raphson step to reoptimize orbitals, thus establishing a new set of orbitals which better balances ground and excited state energies. The computational cost of this correction is exactly that of one coupled-perturbed Hartree-Fock calculation, which is effectively the cost of the CIS calculation itself. In other words, for twice the computational cost of a standard CIS calculation, or roughly the same cost as a linear-response time-dependent Hartree-Fock calculation, one can achieve a balanced, size-consistent description of CT versus non-CT energies, ideally with the accuracy of a much more expensive doubles CIS(D) calculation.

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