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1.
J ECT ; 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38373175

RESUMO

BACKGROUND: Electroconvulsive therapy (ECT) is a significant contemporary medical treatment modality for various mental disorders that have not responded to other treatments. YouTube is a valuable place to get health-related educational content that can have a big impact on patients' and their primary caregivers' behaviors and decisions. OBJECTIVE: The aim of the study is to analyze the content of YouTube videos related to ECT to investigate the quality and reliability of videos as supportive information for patients and their primary caregivers. METHODS: A total of 250 videos related to ECT that are available on YouTube were analyzed. The Global Quality Scale and the modified DISCERN tool were used to assess the quality and reliability of the videos. Details of the content of the video, caregiver appearance, methods of information presentation, source of the video, and video parameters were analyzed as well. RESULT: The analysis revealed that the median total score of Global Quality Scale was 3 (interquartile range, 2; min-max, 1-5), which means the video quality was medium. The median total score of the modified DISCERN tool was 3 (interquartile range, 1; min-max, 0-5), which means the videos were highly reliable. Most of the video sources in the included videos were educational (41.2%, n = 103) from formal caregivers, and there was no significant difference between Global Quality Scale scores, video parameters, and modified DISCERN scores. CONCLUSIONS: YouTube is considered a supportive source of information related to ECT but needs more encouragement from formal caregivers to disseminate high-quality and reliable healthcare content on YouTube platforms to ensure access to accurate information.

2.
Arch Psychiatr Nurs ; 45: 16-25, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37544693

RESUMO

BACKGROUND: Self-management of early warning signs of relapse is critical when it comes to having an impact on the relapse rate and developing methods to successfully handle and manage those signs of relapse. OBJECTIVE: The purpose of this study was to test the validity and reliability of the adapted management of early warning signs of relapse questionnaire. METHODS: Consisted of two main steps: first, adapting and validating, which involved a literature review, a panel of experts, the calculation of the CVI, the Kaiser-Meyer-Olkin (KMO) test, Bartlett's test of sphericity, and exploratory factor analysis (EFA); and secondly, reliability analysis, using the test-retest method, to assess the questionnaire's internal consistency (Cronbach's alpha) and reproducibility (intraclass correlation coefficient-ICC). RESULTS: The results showed that the questionnaire adapted was valid and reliable and can represent each item of the questionnaire for assessing the self-management of early warning signs of relapse. CONCLUSION: This proves that all 20 items used to assess it are appropriate for assessing the effectiveness of the patients' and their primary caregivers' abilities to self-manage early warning signs of relapse.


Assuntos
Reprodutibilidade dos Testes , Humanos , Inquéritos e Questionários , Análise Fatorial , Doença Crônica , Psicometria
3.
Clin Psychol Psychother ; 30(5): 950-964, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37220775

RESUMO

BACKGROUND: Suicidal thoughts and behaviours (STBs) are significant public health challenges that affect a variety of individuals and communities. Despite numerous efforts to discover and refine psychotherapy treatments to minimize STBs, the efficacy of STB treatments remains unclear. OBJECTIVE: Conduct a scoping review to assess the efficacy of using psychotherapy treatments to minimize STBs among individuals with obsessive-compulsive disorder (OCD). METHOD: A scoping review was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews guidelines (PRISMA-ScR) to screen 163 studies published between 2010 and 2021. RESULTS: A total of seven articles that fulfil the eligibility criteria reported that psychotherapy treatments for obsessive-compulsive disorder were found to be effective and applicable approaches to minimize the severity of the OCD symptoms and STBs, despite variance in studies' target samples, types of interventions, periods and indicators. CONCLUSION: The current review has provided evidence showing the significant effects of psychotherapy treatments on various health-related aspects of life for individuals diagnosed with obsessive-compulsive disorder, and it is recommended to use them for enhancing treatment outcomes and minimizing STBs. IMPLICATION FOR PRACTICE: This scoping review verifies the formalization and incorporation of psychotherapy treatments for OCD to minimize STBs into standard practice and highlights the importance of mental health professionals being part of the implementation of these treatments.


Assuntos
Transtorno Obsessivo-Compulsivo , Ideação Suicida , Humanos , Transtorno Obsessivo-Compulsivo/psicologia , Psicoterapia , Resultado do Tratamento
4.
Heart Fail Rev ; 28(1): 207-215, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35435527

RESUMO

Heart failure continues to account for millions of cases and deaths worldwide. Heart transplant is the gold standard for treatment of advanced heart failure. Unfortunately, the supply of donor hearts continues to be limited with the increase in demand for heart transplantation. In this review, we aim to explore the safety and efficacy of using hearts from donors with history of substance use. Despite the theoretical effect of cocaine and alcohol on the cardiovascular system, several studies demonstrate no difference in outcomes (overall survival, graft rejection, graft vasculopathy) when using hearts from patients with history of cocaine and alcohol use. The opioid epidemic has expanded the potential donor pool where the current studies have not shown any adverse outcomes when considering donors with history of opioid use. The currently available evidence would support the use of donor hearts from patients with history of alcohol, cocaine, opioids, and marijuana use. Further studies are needed to evaluate the safety of using donor hearts from patients with history of nicotine use.


Assuntos
Cocaína , Insuficiência Cardíaca , Transplante de Coração , Transtornos Relacionados ao Uso de Substâncias , Humanos , Transplante de Coração/efeitos adversos , Doadores de Tecidos , Insuficiência Cardíaca/cirurgia , Transtornos Relacionados ao Uso de Substâncias/complicações , Etanol , Estudos Retrospectivos
5.
Am J Cardiol ; 179: 83-89, 2022 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-35909017

RESUMO

We postulated that familial idiopathic dilated cardiomyopathy (F-IDC) is associated with a worse prognosis than nonfamilial IDC (nonF-IDC). Patients with F-IDC had either a strong family history and/or proved genetic mutations. We studied long-term prognosis (mean follow-up: 6.1 ± 4.1 years) of 162 patients with IDC (age: 55.5 ± 17.9 years, men: 57.8%, 50% F-IDC) with an implantable cardioverter-defibrillator or cardiac resynchronization therapy. The primary end point was a composite of death, left ventricular (LV) assist device implant, or heart transplantation. The secondary end point was a ventricular arrhythmia event. There was no significant difference in the prevalence of diabetes, hypertension, New York Heart Association class, medical therapy, and years of follow-up between the F-IDC and nonF-IDC groups. Patients with F-IDC were younger than patients with nonF-IDC (49.1 ± 17.0 years vs 61.6 ± 16.5 years, p <0.001). Mean LV ejection fraction was significantly lower in F-IDC group than in the nonF-IDC group (26 ± 12% vs 31 ± 12%, p = 0.022). The primary end point was achieved in 54 patients in F-IDC group (66.7%) versus 19 in the nonF-IDC group (23.5%) (p <0.001). The Kaplan-Meier survival estimates for the composite end point and for ventricular arrhythmia were significantly lower in the F-IDC versus nonF-IDC (log-rank p ≤0.001 and 0.04, respectively). F-IDC was the only multivariable predictor of the primary composite end point (hazard ratio 3.419 [95% confidence interval 1.845 to 6.334], p <0.001). The likelihood of LV remodeling manifested by LV ejection fraction improvement (≥10%) was significantly lower in F-IDC than nonF-IDC (27.1% vs 44.8%, p = 0.042). In conclusion, F-IDC is a predictor of mortality, need for LV assist device, or heart transplantation. F-IDC is associated with significantly lower event-free survival for primary end point and ventricular arrhythmia than nonF-IDC. F-IDC has significantly lower likelihood of LV reverse remodeling than nonF-IDC.


Assuntos
Cardiomiopatia Dilatada , Transplante de Coração , Coração Auxiliar , Adulto , Idoso , Arritmias Cardíacas , Humanos , Masculino , Pessoa de Meia-Idade , Volume Sistólico , Remodelação Ventricular
6.
Issues Ment Health Nurs ; 43(7): 670-682, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35119343

RESUMO

Relapse prevention is an essential component in sustaining positive treatment outcomes.The purpose of this study was to test the efficacy of a relapse prevention intervention on the ability of patients and their primary caregivers to self-detect and manage early warning signs of relapse, and its impact on relapse rate among patients diagnosed with schizophrenia.Quasi-experimental design; one group posttest only, repeated measure time-series design was employed. A total of 40 patients and their primary caregivers represented the sample in this study.The statistical analysis revealed that the effect of relapse prevention intervention on patients and their primary caregivers' ability to self-detect severity and manage early warning signs of relapse has sustainable and positive effect on patients and their primary caregivers from T1 to T3 (patients, M = 9.0-9.3; caregivers, M = 9.7-9.9). Also, positive effect of intervention detected on abilities of patients and primary caregivers to manage EWS from T1 to T3 (patients, M = 35-36.0; caregivers, M = 39.7-38.1). The analysis also showed a low relapse rate (14.9%).The study showed that relapse prevention interventions is effective and applicable approach that psychiatric nurses can use to ensure sustainable positive outcomes of psychiatric healthcare among patients with schizophrenia.


Assuntos
Esquizofrenia , Cuidadores/psicologia , Doença Crônica , Humanos , Jordânia , Recidiva , Esquizofrenia/diagnóstico , Esquizofrenia/prevenção & controle , Prevenção Secundária
7.
J Psychosoc Nurs Ment Health Serv ; 60(7): 47-54, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35041801

RESUMO

Maintaining remission and improving quality of life for individuals with schizophrenia can encourage them to return to work, participate in volunteer opportunities, and establish healthy intimate relationships. The purpose of the current review was to explore the impacts of using relapse prevention interventions on maintaining remission and minimizing relapse rate for individuals with schizophrenia. A scoping review was performed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews guidelines to screen 134 studies published between 2010 and 2020. A total of 14 articles met eligibility criteria. Included studies showed that intervention strategies tailored to meet the needs of individuals with schizophrenia must be developed and applied in different psychiatric settings to maintain remission and minimize relapse rate. [Journal of Psychosocial Nursing and Mental Health Services, 60(7), 47-54.].


Assuntos
Esquizofrenia , Doença Crônica , Humanos , Qualidade de Vida , Recidiva , Prevenção Secundária
8.
BMJ Open ; 11(2): e038349, 2021 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-33593761

RESUMO

OBJECTIVES: This study aims to examine the outcome of haematological and patients with solid cancer presenting with sepsis to the emergency department (ED). DESIGN: Single-centred, retrospective cohort study. Setting conducted at an academic emergency department of a tertiary hospital. PARTICIPANTS: All patients >18 years of age admitted with sepsis were included. INTERVENTIONS: Patients were stratified into two groups: haematological and solid malignancy. PRIMARY AND SECONDARY OUTCOME: The primary outcome of the study was in-hospital mortality. Secondary outcomes included intensive care unit (ICU) mortality, ICU and hospital lengths of stay and mechanical ventilation duration. RESULTS: 442 sepsis cancer patients were included in the study, of which 305 patients (69%) had solid tumours and 137 patients (31%) had a haematological malignancy. The mean age at presentation was 67.92 (±13.32) and 55.37 (±20.85) (p<0.001) for solid and liquid tumours, respectively. Among patients with solid malignancies, lung cancer was the most common source (15.6%). As for the laboratory workup, septic solid cancer patients were found to have a higher white blood count (12 576.90 vs 9137.23; p=0.026). During their hospital stay, a total of 158 (51.8%) patients with a solid malignancy died compared with 57 (41.6%) patients with a haematological malignancy (p=0.047). There was no statistically significant association between cancer type and hospital mortality (OR 1.15 for liquid cancer p 0.58). There was also no statistically significant difference regarding intravenous fluid administration, vasopressor use, steroid use or intubation. CONCLUSION: Solid tumour patients with sepsis or septic shock are at the same risk of mortality as patients with haematological tumours. However, haematological malignancy patients admitted with sepsis or septic shock have higher rates of bacteraemia.


Assuntos
Neoplasias , Sepse , Choque Séptico , Serviço Hospitalar de Emergência , Mortalidade Hospitalar , Humanos , Unidades de Terapia Intensiva , Tempo de Internação , Neoplasias/complicações , Estudos Retrospectivos , Sepse/complicações
9.
J Hepatol ; 75(1): 142-149, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33476745

RESUMO

BACKGROUND & AIMS: Patients with cirrhosis and significant coronary artery disease (CAD) are at risk of peri-liver transplantation (LT) cardiac events. The coronary artery disease in liver transplantation (CAD-LT) score and algorithm aim to predict the risk of significant CAD in LT candidates and guide pre-LT cardiac evaluation. METHODS: Patients who underwent pre-LT evaluation at Indiana University (2010-2019) were studied retrospectively. Stress echocardiography (SE) and cardiac catheterization (CATH) reports were reviewed. CATH was performed for predefined CAD risk factors, irrespective of normal SE. Significant CAD was defined as CAD requiring percutaneous or surgical intervention. A multivariate regression model was constructed to assess risk factors. Receiver-operating curve analysis was used to compute a point-based risk score and a stratified testing algorithm. RESULTS: A total of 1,771 pre-LT patients underwent cardiac evaluation, including results from 1,634 SE and 1,266 CATH assessments. Risk-adjusted predictors of significant CAD at CATH were older age (adjusted odds ratio 1.05; 95% CI 1.03-1.08), male sex (1.69; 1.16-2.50), diabetes (1.57; 1.12-2.22), hypertension (1.61; 1.14-2.28), tobacco use (pack years) (1.01; 1.00-1.02), family history of CAD (1.63; 1.16-2.28), and personal history of CAD (6.55; 4.33-9.90). The CAD-LT score stratified significant CAD risk as low (≤2%), intermediate (3% to 9%), and high (≥10%). Among patients who underwent CATH, a risk-based testing algorithm (low: no testing; intermediate: non-invasive testing vs. CATH; high: CATH) would have identified 97% of all significant CAD and potentially avoided unnecessary testing (669 SE [57%] and 561 CATH [44%]). CONCLUSIONS: The CAD-LT score and algorithm (available at www.cad-lt.com) effectively stratify pre-LT risk for significant CAD. This may guide more targeted testing of candidates with fewer tests and faster time to waitlist. LAY SUMMARY: The coronary artery disease in liver transplantation (CAD-LT) score and algorithm effectively stratify patients based on their risk of significant coronary artery disease. The CAD-LT algorithm can be used to guide a more targeted cardiac evaluation prior to liver transplantation.


Assuntos
Doença da Artéria Coronariana , Cirrose Hepática , Risco Ajustado/métodos , Fatores Etários , Algoritmos , Comorbidade , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/prevenção & controle , Feminino , Humanos , Cirrose Hepática/epidemiologia , Cirrose Hepática/cirurgia , Transplante de Fígado/efeitos adversos , Transplante de Fígado/métodos , Masculino , Anamnese , Pessoa de Meia-Idade , Planejamento de Assistência ao Paciente/normas , Cuidados Pré-Operatórios/métodos , Cuidados Pré-Operatórios/normas , Fatores de Risco , Fatores Sexuais , Fumar/epidemiologia
10.
Front Cardiovasc Med ; 7: 613271, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33344519

RESUMO

Atrial fibrillation (AF) and cardiometabolic syndrome (CMS) have been linked to inflammation and fibrosis. However, it is still unknown which inflammatory cytokines contribute to the pathogenesis of AF. Furthermore, cardiometabolic syndrome (CMS) risk factors such as obesity, hypertension, insulin resistance/glucose intolerance are also associated with inflammation and increased level of cytokines and adipokines. We hypothesized that the inflammatory immune response is exacerbated in patients with both AF and CMS compared to either AF or CMS alone. We investigated inflammatory cytokines and fibrotic markers as well as cytokine genetic profiles in patients with lone AF and CMS. CMS, lone AF patients, patients with both lone AF and CMS, and control patients were recruited. Genetic polymorphisms in inflammatory and fibrotic markers were assessed. Serum levels of connective tissue growth factor (CTGF) were tested along with other inflammatory markers including platelet-to-lymphocyte ratio (PLR), monocyte-to-HDL ratio (MHR) in three groups of AF+CMS, AF, and CMS patients. There was a trend in the CTGF levels for statistical significance between the AF and AF+CMS group (P = 0.084). Genotyping showed high percentages of patients in all groups with high secretor genotypes of Interleukin-6 (IL-6) (P = 0.037). Genotyping of IFN-γ and IL-10 at high level showed an increase in expression in the AF + CMS group compared to AF and CMS alone suggesting an imbalance between the inflammatory and anti-inflammatory cytokines which is exacerbated by AF. Serum cytokine inflammatory cytokine levels showed that IL-4, IL-5, IL-10, IL-17F, and IL-22 were significant between the AF, AF+CMS, and CMS patients. Combination of both CMS and AF may be associated with a higher degree of inflammation than what is seen in either CMS or AF alone. Thus, the identification of a biomarker capable of identifying metabolic syndrome associated with disease will help in identification of a therapeutic target in treating this devastating disease.

11.
Front Med (Lausanne) ; 7: 517999, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33195290

RESUMO

Background: Patients with heart failure with preserved ejection fraction (HFpEF) may be at a higher risk of mortality from sepsis than patients without heart failure. Objective: The aim of this study is to compare sepsis-related morbidity and mortality between patients with HFpEF and patients without heart failure presenting to the emergency department (ED) of a tertiary medical center. Design: Single-center retrospective cohort study conducted at an academic ED between January 1, 2015 and December 31, 2018. Patients: Patients with a diagnosis of sepsis were included. Main Measures: Bivariate and multivariate analyses were performed to look at differences in demographics, infection, and treatment parameters as well as outcomes of patients with sepsis. The primary outcome of the study was in-hospital mortality. Secondary outcomes included ED mortality, lengths of stay, and treatment differences between both groups. Key Results: A total of 1,092 patients presented with sepsis to the ED, of which 305 (27.93%) had HFpEF. There was no significant difference in in-hospital mortality between the two groups (40.7% vs. 37.4%; p = 0.314). However, there was a significant increase in ED mortality for septic HFpEF patients compared to non-heart failure patients (2.4 vs. 0.4%; p = 0.003). Septic HFpEF patients presenting to the ED were older than non-heart failure patients (76.84 vs. 68.44 years old; p < 0.0001). On the other hand, there was no significant increase in the use of vasopressors in the first 24 h between both groups. There was a significantly higher rate of intubation in the first 48 h for septic HFpEF patients (17.5 vs. 8.9%; p < 0.0001). Finally, there was significantly less intravenous fluid requirement at 6 h (1.94 L vs. 2.41L; p < 0.0001) and 24 h (3.11 L vs. 3.54L; p = 0.004) for septic patients with HFpEF compared to non-heart failure patients. Conclusion: Septic HFpEF patients experienced an increase in ED mortality, intubation, and steroid use compared to septic non-heart failure patients.

12.
Int J Cardiovasc Imaging ; 36(10): 1953-1962, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32757119

RESUMO

Negative stress echocardiography (NSE) is associated with low cardiovascular morbidity and overall mortality. We aimed to determine the clinical and echocardiographic predictors of overall and cardiovascular outcomes following NSE. Patients who underwent SE between 2013 and 2017 were reviewed. Patients with a history of solid organ transplant or being evaluated for transplant, history of end-stage renal or liver disease, and positive SE were excluded. NSE results were divided into negative diagnostic if patient reached target heart rate (THR) and had no wall motion abnormality (WMA) at rest or stress; negative non-diagnostic if patient had no WMA but did not reach THR or if image quality was non-diagnostic; and abnormal non-ischemic if patient had a resting WMA not worsened at stress along with a personal history of coronary artery disease (CAD). New CAD lesion at 1 year was defined as ≥ 50% stenosis on cardiac catheterization. Of 4119 patients with SE, 2575 were included. All-cause mortality rate was 1.1%/year and CAD rate was 3.1%/year. Predictors of all-cause mortality were age, male gender, history of smoking and being selected for dobutamine SE. Predictors of a new CAD lesion at 1 year were male gender, diabetes, personal history of CAD and abnormal non-ischemic SE. We identified clinical and echocardiographic characteristics in a subset of NSE patients who are at higher risk for subsequent adverse events. These characteristics should be accounted for during the clinical interpretation of SE, and patients found at increased risk for morbidity and mortality warrant continued follow-up.


Assuntos
Doença da Artéria Coronariana/diagnóstico por imagem , Ecocardiografia sob Estresse , Teste de Esforço , Agonistas de Receptores Adrenérgicos beta 1/administração & dosagem , Idoso , Doença da Artéria Coronariana/mortalidade , Doença da Artéria Coronariana/fisiopatologia , Dobutamina/administração & dosagem , Feminino , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo
13.
J Neonatal Perinatal Med ; 13(2): 267-273, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31707376

RESUMO

Sustained fetal supraventricular tachycardia (SVT) complicated by hydrops fetalis carries a significant risk of morbidity and mortality. While there is no clear consensus on first- and second-line therapy options for the management of fetal SVT with or without hydrops fetalis, there exists significant nonrandomized experience with a number of antiarrhythmic agents that has founded the basis for management. Furthermore, recently published meta-analyses and ongoing multicenter prospective studies have aimed to bridge the gap in the literature. We report two cases of sustained fetal SVT with severe secondary hydrops fetalis managed successfully with flecainide-sotalol combination therapy in one case and sotalol-digoxin combination therapy in the second and review the literature for the management of fetal SVT.


Assuntos
Antiarrítmicos/uso terapêutico , Digoxina/uso terapêutico , Doenças Fetais/tratamento farmacológico , Flecainida/uso terapêutico , Hidropisia Fetal/tratamento farmacológico , Sotalol/uso terapêutico , Taquicardia Supraventricular/tratamento farmacológico , Adulto , Quimioterapia Combinada , Feminino , Doenças Fetais/diagnóstico , Humanos , Hidropisia Fetal/diagnóstico por imagem , Hidropisia Fetal/etiologia , Gravidez , Taquicardia Supraventricular/complicações , Taquicardia Supraventricular/diagnóstico , Adulto Jovem
17.
Acta Crystallogr C Struct Chem ; 72(Pt 2): 112-8, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26846494

RESUMO

The design of new organic-inorganic hybrid ionic materials is of interest for various applications, particularly in the areas of crystal engineering, supramolecular chemistry and materials science. The monohalogenated intermediates 1-(2-chloroethyl)pyridinium chloride, C5H5NCH2CH2Cl(+)·Cl(-), (I'), and 1-(2-bromoethyl)pyridinium bromide, C5H5NCH2CH2Br(+)·Br(-), (II'), and the ionic disubstituted products 1,1'-(ethylene-1,2-diyl)dipyridinium dichloride dihydrate, C12H14N2(2+)·2Cl(-)·2H2O, (I), and 1,1'-(ethylene-1,2-diyl)dipyridinium dibromide, C12H14N2(2+)·2Br(-), (II), have been isolated as powders from the reactions of pyridine with the appropriate 1,2-dihaloethanes. The monohalogenated intermediates (I') and (II') were characterized by multinuclear NMR spectroscopy, while (I) and (II) were structurally characterized using powder X-ray diffraction. Both (I) and (II) crystallize with half the empirical formula in the asymmetric unit in the triclinic space group P-1. The organic 1,1'-(ethylene-1,2-diyl)dipyridinium dications, which display approximate C2h symmetry in both structures, are situated on inversion centres. The components in (I) are linked via intermolecular O-H...Cl, C-H...Cl and C-H...O hydrogen bonds into a three-dimensional framework, while for (II), they are connected via weak intermolecular C-H...Br hydrogen bonds into one-dimensional chains in the [110] direction. The nucleophilic substitution reactions of 1,2-dichloroethane and 1,2-dibromoethane with pyridine have been investigated by ab initio quantum chemical calculations using the 6-31G** basis. In both cases, the reactions occur in two exothermic stages involving consecutive SN2 nucleophilic substitutions. The isolation of the monosubstituted intermediate in each case is strong evidence that the second step is not fast relative to the first.

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