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1.
Front Neurol ; 15: 1395312, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38846040

RESUMO

Introduction: The efficacy of neurologic music therapy (NMT) techniques for the treatment of non-fluent aphasia has been widely accepted by the rehabilitation medical community. However, consensus on which dimensions of speech function can be improved by NMT techniques and standardized intervention dosage remains elusive. This study aimed to provide evidence regarding the efficacy of NMT in improving speech function and explore the optimal intervention dose. A systematic review and meta-analysis were conducted to search for randomized clinical trials and open-label trials that evaluated speech functions after NMT. Methods: We searched all papers and reviews published from database inception to July 2023, including PubMed, Cochrane Library, Web of Science, Embase, and CNKI. Statistical analyses were mainly carried out on RevManV5.4.1 and pooled using a random-effects model. The primary outcome was the standardized mean difference (SMD) in speech functions, determined by calculating the change in speech functions score from baseline to the primary endpoint in the NMT group versus the control arm. Results: A total of 11 studies with 329 patients were included. NMT had a positive effect on repetition ability (SMD = 0.37, 95%CI [0.12, 0.62], p < 0.05), but did not lead to significant differences in naming, comprehension, spontaneous speech, or communication. When the intervention time was >20 h, NMT exhibited a significant advantage at improving repetition ability (SMD = 0.43, 95%CI [0.06, 0.79], p < 0.05). Discussion: This study provides evidence supporting the NMT enhancement of repetition ability in patients with non-fluent aphasia. Future large-sample studies are required to determine the optimal intervention dose of music therapy for different subtypes of non-fluent aphasia. Systematic review registration: PROSPERO, identifier CRD42023470313.

2.
Ecotoxicol Environ Saf ; 278: 116406, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38728941

RESUMO

Cadmium contamination inevitably affects the microbially mediated transformation of nitrogen in soils with wheat straw return. The responses of nitrogen functional microorganisms to cadmium in acidic and alkaline soils under wheat straw returned are still unclear. In this study, quantitative polymerase chain reaction (qPCR) and sequencing of nitrifying and denitrifying bacteria were performed to investigate the effects of wheat straw application on nitrogen conversion in different Cd-contaminated soils during an incubation experiment. Results showed that the presence of Cd decreased the abundance of hao gene catalyzing nitrification and norB gene catalyzing denitrification process, resulting the accumulation of NH4+-N and reduction of NO3--N in the acidic soils. Additionally, Cd-contamination stimulates the nitrification catalyzed by bacterial amoA gene and thus reduced the NH4+-N content in the alkaline soils. Meanwhile, Cd dominated the decrease of NO3--N content by promoting denitrification process catalyzed by nirS gene. Among all nitrifying and denitrifying microorganisms, Nitrosospira are tolerant to Cd stress under alkaline condition but sensitive to acidic condition, which dominantly harbored hao gene in the acidic soils and bacterial amoA gene in the alkaline soils. This study aimed to provide reasonable information for the rational adoption of wheat straw returning strategies to realize nitrogen regulation in Cd-contaminated farmland soil.


Assuntos
Cádmio , Desnitrificação , Nitrificação , Microbiologia do Solo , Poluentes do Solo , Triticum , Cádmio/análise , Cádmio/metabolismo , Poluentes do Solo/análise , Poluentes do Solo/metabolismo , Nitrogênio/metabolismo , Solo/química , Bactérias/metabolismo , Bactérias/genética , Ciclo do Nitrogênio
3.
Front Microbiol ; 15: 1384095, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38711967

RESUMO

Introduction: This study explored the causal connections between gut microbiota (GM), urinary tract infection (UTI), and potential metabolite mediators using Mendelian randomization (MR). Methods: We utilized summary statistics from the most comprehensive and extensive genome-wide association studies (GWAS) available to date, including 196 bacterial traits for GM, 1,091 blood metabolites, 309 metabolite ratios, alongside UTI data from ukb-b-8814 and ebi-a-GCST90013890. Bidirectional MR analyses were conducted to investigate the causal links between GM and UTI. Subsequently, two MR analyses were performed to identify the potential mediating metabolites, followed by a two-step MR analysis to quantify the mediation proportion. Results: Our findings revealed that out of the total 15 bacterial traits, significant associations with UTI risk were observed across both datasets. Particularly, taxon g_Ruminococcaceae UCG010 displayed a causal link with a diminished UTI risk in both datasets (ukb-b-8814: odds ratio [OR] = 0.9964, 95% confidence interval [CI] = 0.9930-0.9997, P = 0.036; GCST90013890: OR = 0.8252, 95% CI = 0.7217-0.9436, P = 0.005). However, no substantial changes in g_Ruminococcaceae UCG010 due to UTI were noted (ukb-b-8814: ß = 0.51, P = 0.87; ebi-a-GCST90013890: ß = -0.02, P = 0.77). Additionally, variations in 56 specific metabolites were induced by g_Ruminococcaceae UCG010, with N-acetylkynurenine (NAK) exhibiting a causal correlation with UTI. A negative association was found between g_Ruminococcaceae UCG010 and NAK (OR: 0.8128, 95% CI: 0.6647-0.9941, P = 0.044), while NAK was positively associated with UTI risk (OR: 1.0009; 95% CI: 1.0002-1.0016; P = 0.0173). Mediation analysis revealed that the association between g_Ruminococcaceae UCG010 and UTI was mediated by NAK with a mediation proportion of 5.07%. Discussion: This MR study provides compelling evidence supporting the existence of causal relationships between specific GM taxa and UTI, along with potential mediating metabolites.

4.
PLoS One ; 19(4): e0299054, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38574027

RESUMO

Wheat straw returning is widely practiced in agriculture; therefore, it is critical to determine the physicochemical and bacterial indicators in soil for the organic carbon storage, accumulative C mineralization, total nitrogen improvement, and nitrogen mineralization in various soil types after wheat straw returning. This study evaluated the influenced indicators of wheat straw addition on soil organic carbon and nitrogen transformation in diverse soil types. For this purpose, an incubation experiment was conducted to analyze the carbon and nitrogen transformation in soil from eight Chinese provinces treated with the same dry weight of wheat straw. The results indicated that the primary physicochemical and bacterial indicators that predict the carbon and nitrogen transformations in the acidic and alkaline soils were different. Of all the natural physicochemical properties of soil, cation exchange capacity and clay content were significantly correlated with organic carbon, mineralized carbon, total nitrogen, and mineralized nitrogen in the alkaline soil. In the acidic soil, the initial C/N ratio of soil was the most significant indicator of carbon and nitrogen transformation. From the perspective of the carbon- and nitrogen-relating bacterial communities, Proteobacteria were largely responsible for the accumulative C mineralization in both types of soil. Furthermore, Proteobacteria strongly regulated the organic carbon storage in the acidic soil after wheat straw addition, whereas Gemmatimonadetes was the main predicted indicator in the alkaline soil. Additionally, total nitrogen and mineralized nitrogen levels were largely explained by Bifidobacterium and Luteimonas in the alkaline soil and by Nitrospira and Bdellovibrio in the acidic soil. Soil physicochemical and biological properties significantly influence soil carbon and nitrogen transformation, which should be considered crucial indicators to guide the rational regulation of straw return in several areas.


Assuntos
Carbono , Solo , Solo/química , Triticum , Nitrogênio/análise , Agricultura/métodos , Bactérias , Proteobactérias , Fertilizantes
5.
Int J Antimicrob Agents ; 63(6): 107158, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38537722

RESUMO

Rifampicin is the most powerful first-line antibiotic for tuberculosis, which is caused by Mycobacterium tuberculosis. Although accumulating evidence from sequencing data of clinical M. tuberculosis isolates suggested that mutations in the rifampicin-resistance-determining region (RRDR) are strongly associated with rifampicin resistance, the comprehensive characterisation of RRDR polymorphisms that confer this resistance remains challenging. By incorporating I-SceI sites for I-SceI-based integrant removal and utilizing an L5 swap strategy, we efficiently replaced the integrated plasmid with alternative alleles, making mass allelic exchange feasible in mycobacteria. Using this method to establish a fitness-related gain-of function screen, we generated a mutant library that included all single-amino-acid mutations in the RRDR, and identified the important positions corresponding to some well-known rifampicin-resistance mutations (Q513, D516, S522, H525, R529, S531). We also detected a novel two-point mutation located in the RRDR confers a fitness advantage to M. smegmatis in the presence or absence of rifampicin. Our method provides a comprehensive insight into the growth phenotypes of RRDR mutants and should facilitate the development of anti-tuberculosis drugs.


Assuntos
Farmacorresistência Bacteriana , Mycobacterium tuberculosis , Rifampina , Rifampina/farmacologia , Farmacorresistência Bacteriana/genética , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/efeitos dos fármacos , Mutação , Mutagênese , Antituberculosos/farmacologia , Mycobacterium smegmatis/genética , Mycobacterium smegmatis/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Ensaios de Triagem em Larga Escala/métodos , Humanos
6.
J Adv Nurs ; 80(4): 1523-1530, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37855380

RESUMO

AIMS: This study aims to explore the experiences of rehabilitation specialist nurses in providing bowel care to stroke patients and to identify the factors that either facilitate or hinder their practice. DESIGN: This was a descriptive qualitative design study. METHODS: Between May 2022 and October 2022, we conducted in-depth and semi-structured interviews with 12 rehabilitation specialist nurses from two tertiary hospitals in Changsha, China. Thematic analysis was employed to analyse the interview transcripts. FINDINGS: Three key themes were revealed from our analysis: (1) acceptance of bowel care as a process, (2) high level of recognition improves the experience and (3) challenges stemming from limited knowledge and rights. Acceptance of bowel care as a dynamic process, coupled with a high level of recognition, enabled nurses to prioritize the health and safety of patients over personal feelings and achieve professional accomplishments. However, they encountered challenges in terms of professional development and restricted prescribing rights for bowel care. CONCLUSION: The experiences of rehabilitation specialist nurses in providing bowel care are dynamic. These findings have important implications for healthcare improvement, including the need for collaboration with healthcare professionals and nurturing nurses' self-identity, comprehensive training plans, innovative programs and expanding the scope of rehabilitation specialist nurses' rights. IMPACT: This study enhances our understanding of the challenges faced by rehabilitation specialist nurses caring for stroke patients with neurogenic bowel dysfunction. The findings provide insights into how to enhance bowel care experience and develop further in this field. REPORTING METHOD: This study adhered to the EQUATOR guideline and utilized the COREQ checklist. PATIENT OR PUBLIC CONTRIBUTIONS: This study involved participants who were registered nurses, and there were no contributions from patients or public.


Assuntos
Enfermeiras e Enfermeiros , Acidente Vascular Cerebral , Humanos , Pesquisa Qualitativa , Atenção à Saúde , Pessoal de Saúde , China
8.
Trials ; 24(1): 633, 2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37789378

RESUMO

BACKGROUND: Neurogenic bowel dysfunction (NBD) is a prevalent complication among stroke patients, significantly affecting their quality of life, duration of hospitalization, medical expenses, and even mortality. Although current guidelines suggest a conservative strategy for addressing bowel dysfunction, which includes techniques such as digital rectal stimulation (DRS) and abdominal massage, the availability of interventions remains limited in healthcare facilities. METHODS: This study follows a prospective randomized controlled parallel-group clinical trial design. The control group will receive standard care, while the intervention group will undergo a program that combines DRS and abdominal massage in addition to standard care. The duration of the intervention for both groups will be 6 weeks. The primary outcome measures will be the Wexner score. Furthermore, secondary outcomes measure will be assessed, including Bristol score, Patient Assessment of Constipation-Quality of Life (PAC-QoL), and Fecal Incontinence Quality of Life (FI-QoL). DISCUSSION: This study aims to evaluate the effectiveness and safety of a bowel rehabilitation program for stroke patients with NBD. The findings will provide information that can contribute to the formulation of bowel management strategies. TRIAL REGISTRATION: The study has been registered in the Chinese Clinical Registry under the number ChiCTR2300071709. This registration was completed on May 23, 2023. All items from the World Health Organization Trial Registration Data set are described in this manuscript.


Assuntos
Intestino Neurogênico , Acidente Vascular Cerebral , Humanos , Intestino Neurogênico/diagnóstico , Intestino Neurogênico/etiologia , Intestino Neurogênico/terapia , Qualidade de Vida , Estudos Prospectivos , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/terapia , Massagem/métodos , Resultado do Tratamento , Ensaios Clínicos Controlados Aleatórios como Assunto
9.
J Korean Acad Nurs ; 53(4): 412-425, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37673816

RESUMO

PURPOSE: Nurses play an important role in ensuring patient rehabilitation and are involved in all aspects of multidimensional rehabilitation. Therefore, strengthening rehabilitation nursing education is vital to ascertain high-quality rehabilitation and optimum outcomes. This study examined the effectiveness of a new teaching reform-a modified Six-Sigma-based training program-against a conventional educational program on rehabilitation specialist nurses' core competencies, post-training performance, and satisfaction. METHODS: A quasi-randomized controlled trial was conducted to assess the effectiveness of the modified training program. We recruited 56 learners from the 2020 training course at the Hunan Rehabilitation Specialist Nurse Training Base as the control group. Sixty learners from the base's 2021 training course were recruited as the intervention group. Data were collected in a consistent manner from both groups after the training program was implemented. RESULTS: Those who underwent the modified training program showed better improvement in all core competencies than those who underwent the conventional training program (p < .05); the scores for theoretical knowledge, clinical nursing lectures, reviews, and nursing case management improved significantly following the teaching reform (p < 0.05). Further, overall satisfaction as well as base management and theoretical teaching satisfaction improved significantly (p < .05). CONCLUSION: The modified training program strengthens rehabilitation nurses' base management abilities; enhances their core competencies; expands their interest in and breadth, depth, and practicability of theoretical courses; and updates the teaching methods.


Assuntos
Enfermeiros Especialistas , Cuidados de Enfermagem , Humanos , Escolaridade , Conhecimento
10.
J Inorg Biochem ; 236: 111983, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36087436

RESUMO

Three di-organotin(IV) complexes have been synthesized by the reaction of Schiff base di-acylhydrazone ligands bis(5-chlorosalicylaldehyde) adipoylhydrazone and R2SnCl2 [R = Me (1), Ph (2), n-Bu (3)]. Structures of all complexes were characterized by 1H, 13C, 119Sn NMR, elemental analysis, IR and mass spectrometry. Experimental results showed that the symmetric diacylhydrazone ligands coordinate the tin atom in a hexadentate form, where the tin atom shows a penta-coordination, in a distorted triangular bipyramid geometry. Using MTT method, in vitro cytotoxicity of three complexes was determined against three cancer cell lines (A549, HeLa, HepG-2). Studies reveal that complex 3 showed the strongest cytotoxic activity among the three complexes, which may be correlated with the generation of intracellular reactive oxygen species. Uptake of complex 3 into cells and promotion of reactive oxygen species were visualized by confocal fluorescence imaging.


Assuntos
Compostos Orgânicos de Estanho , Bases de Schiff , Humanos , Ligantes , Compostos Orgânicos de Estanho/química , Compostos Orgânicos de Estanho/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Bases de Schiff/química , Bases de Schiff/farmacologia , Estanho/química
11.
Front Surg ; 9: 899033, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35599803

RESUMO

Objective: To discuss the influence of psychological nursing procedure on negative emotion, stress state, quality of life and nursing satisfaction in patients with lung cancer radical operation. Methods: 106 patients with lung cancer who underwent radical resection in our hospital from September 2019 to September 2021 were selected. According to the intervention time, patients were divided into Group A and Group B, with 53 cases in each group. Group A received routine nursing, Group B used psychological nursing procedure on the basis of Group A. The negative emotions, stress state, quality of life and nursing satisfaction of patient were observed. Results: Self-rating anxiety scale and self-rating depression scale scores of Group B were lower than Group A (P < 0.05). The levels of norepinephrine, epinephrine and cortisol in Group B were lower than Group A (P < 0.05). Generic quality of life inventory-74 scores of Group B were higher than Group A (P < 0.05). The nursing satisfaction of Group B (88.68%) was higher than Group A (73.58%) (P < 0.05). Conclusion: Psychological nursing procedure is conducive to reducing the negative emotion, relieving stress reaction, improving the quality of life, increasing nursing satisfaction of patients with lung cancer radical operation.

12.
Biotechnol J ; 15(8): e1900430, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32170989

RESUMO

Cyclin D1 is a key regulatory factor of the G1 to S transition during cell cycle progression. Aberrant cyclin D gene amplification and abnormal protein expression have been linked to hepatocellular carcinoma (HCC) tumorigenesis. Intrabodies, effective anticancer therapies that specifically inhibit target protein function within all intracellular compartments, may block cyclin D1 function. Here, a single-chain variable fragment (scFv) antibody against cyclin D1 (ADκ) selected from a human semi-synthetic phage display scFv library is expressed in Escherichia coli as soluble ADκ. Purified ADκ specifically binds to recombinant and endogenous cyclin D1 with high affinity. To enable blocking of intracellular cyclin D1 activity, an endoplasmic reticulum (ER) retention signal sequence is added to the ADκ sequence to encode anti-cyclin D1 intrabody ER-ADκ. Transfection of HepG2 cells with expression vector encoding ER-ADκ elicited intracellular ER-ADκ expression leading to cyclin D1 binding, significant G1 phase arrest, and apoptosis that are mechanistically tied to decreased intracellular phosphorylated retinoblastoma protein (Rb) levels. Meanwhile, ER-ADκ dramatically inhibited subcutaneous human HCC xenografts growth in nude mice in vivo after injection of tumors with expression vector encoding ER-ADκ. These results demonstrate the potential of intrabody-based cyclin D1 targeting therapy as a promising treatment for HCC.


Assuntos
Carcinoma Hepatocelular , Divisão Celular , Proliferação de Células , Ciclina D1 , Anticorpos de Cadeia Única , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Ciclo Celular , Divisão Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ciclina D1/genética , Células Hep G2 , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Camundongos , Camundongos Nus , Anticorpos de Cadeia Única/genética , Anticorpos de Cadeia Única/farmacologia , Anticorpos de Cadeia Única/uso terapêutico
13.
Biomed Pharmacother ; 123: 109783, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31855737

RESUMO

Acetaminophen (APAP) overdose has become the most common cause of drug-induced acute liver failure. Angiogenesis and redox homeostasis play an important role in liver protection and repair of APAP-induced acute liver injury (AILI). Hypoxia inducible factor-1 (HIF-1) is a transcription factor that plays a crucial role in regulating the expression of genes associated with angiogenesis, redox homeostasis and energy balance. Prolyl hydroxylase 2 (PHD2) predominantly hydroxylates proline residues in HIF-1α to promote its degradation. In our previous study, we reported an intrabody against PHD2 (ER-INP) that enhances angiogenesis by blocking PHD2 activity to increase HIF-1α abundance and activity. The present study was designed to explore the role and possible mechanisms of ER-INP in AILI in mice. Mice were pretreated intravenously with ER-INP before intraperitoneal injection of APAP to induce AILI. The results showed that pretreatment with ER-INP dramatically decreased the high ALT and AST activities and significantly ameliorated the centrilobular necrosis induced by APAP administration. ER-INP expression promoted angiogenesis in vivo by upregulating the mRNA and protein levels of HIF-1α target genes. Meanwhile, ER-INP pretreatment restored redox homeostasis, verified by reinforcement of PRDX4 activity and suppression of GSH depletion. This study demonstrated that ER-INP protects against AILI in part by increasing angiogenesis and maintaining redox homeostasis. These results indicate that ER-INP may provide a potential liver protection strategy against AILI in the future.


Assuntos
Acetaminofen/intoxicação , Anticorpos/imunologia , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Prolina Dioxigenases do Fator Induzível por Hipóxia/imunologia , Animais , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/imunologia , Células HEK293 , Homeostase/imunologia , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Neovascularização Fisiológica/imunologia , Oxirredução/efeitos dos fármacos , Células RAW 264.7
14.
Med Sci Monit ; 24: 4262-4270, 2018 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-29926841

RESUMO

BACKGROUND The POZ/BTB and AT-hook-containing Zinc finger protein 1 (PATZ1) is a ubiquitously expressed transcription factor belonging to the POZ domain Krüppel-like zinc finger (POK) family. It is involved in the pathogenesis of a growing list of human diseases, including cancer. The effect of PATZ1 on serous ovarian carcinoma (SOC) remains unclear. This study initially explored the clinical significance of PATZ1 in patients with SOC, the relationship between its expression and the prognosis of SOC patients, and its role in tumor proliferation and invasion. MATERIAL AND METHODS Immunohistochemistry and quantitative real-time polymerase chain reaction (qPCR) were performed to characterize the expression of PATZ1 in SOC tissues. The relationship between PATZ1 expression and the clinicopathological features of patients with SOC was analyzed by chi-square test. Kaplan-Meier method and Cox regression analyses were utilized to evaluate the prognosis of SOC. PATZ1-constructed transfection-mediated overexpression was conducted. The CCK-8 assay was performed to examine the proliferation, while Transwell assay was used to detect the invasive capability. RESULTS The results of IHC and qPCR analyses showed that the expression of PATZ1 in cancerous tissue was significantly lower than that in non-cancerous tissues. Meanwhile, PATZ1 expression was significantly associated with tumor differentiation and LN metastasis. Survival analysis showed that PATZ1 expression was one of the independent prognosis factors for overall survival of SOC patients. In addition, overexpression of PATZ1 inhibited the proliferation and invasion of OVCAR3 cells by in vitro experiments. CONCLUSIONS Our data suggest that PATZ1 is a novel prognostic marker in SOC.


Assuntos
Fatores de Transcrição Kruppel-Like/metabolismo , Neoplasias Epiteliais e Glandulares/metabolismo , Neoplasias Ovarianas/metabolismo , Proteínas Repressoras/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Epitelial do Ovário , Diferenciação Celular/fisiologia , Linhagem Celular Tumoral , Progressão da Doença , Feminino , Humanos , Fatores de Transcrição Kruppel-Like/genética , Metástase Linfática , Pessoa de Meia-Idade , Metástase Neoplásica , Neoplasias Epiteliais e Glandulares/genética , Neoplasias Epiteliais e Glandulares/patologia , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Prognóstico , Proteínas Repressoras/genética , Estudos Retrospectivos , Membrana Serosa/metabolismo , Membrana Serosa/patologia
15.
Inorg Chem ; 49(8): 3688-90, 2010 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-20337485

RESUMO

A tetranuclear manganese complex, [Mn(4)(hmp)(6)(N(CN)(2))(4)(H(2)O)(2)] [1; Hhmp = 2-(hydroxymethyl)pyridine; N(CN)(2)(-) = dicyanamide anion], was synthesized and characterized by single-crystal X-ray diffraction, bond valence sum calculations, IR spectra, elemental analysis, and magnetic measurements. The structure of 1 consists of a linear [Mn(II)(2)Mn(III)(2)] core formed by six hmp(-) groups linking Mn(II/III) ions. Magnetic studies show that 1 behaves as a single-molecule magnet with ferromagnetic coupling between the metal centers.

16.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 11): m1314, 2009 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-21578077

RESUMO

The title complex, [Na(C(18)H(22)O(5))(H(2)O)](2)[Co(NCS)(4)], consists of two aqua-(2,3-naphtho-15-crown-5)sodium complex cations and one [Co(NCS)(4)](2-) complex anion, which has crystallographic symmetry. In the anion, the Co(II) centre is coordinated by the N atoms of four NCS(-) ligands in a distorted tetra-hedral geometry. In the complex cations, the Na(I) centre is coordinated by five O atoms of the 2,3-naphtho-15-crown-5 ligand and one water O atom. The complex mol-ecules form a two-dimensional network via weak O-H⋯S inter-actions between adjacent cations and anions.

17.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 4): m557, 2008 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-21202013

RESUMO

The title complex, [Mn(NCS)(2)(C(13)H(19)NO(4))] {systematic name: [3,6,9,12-tetra-oxa-18-aza-bicyclo-[12.3.1]octa-cosa-14(18),15,17-triene-κ(5)N,O,O',O'',O''']bis-(thio-cyanato-κN)manganese(I-I)}, was obtained by the reaction of MnCl(2)·4H(2)O and NaSCN with pyridino-15-crown-5. The Mn(2+) center has a distorted penta-gonal bipyramidal coordination geometry, coordinated by four O atoms and one N atom of the pyridino-15-crown-5 mol-ecule, and by the N atoms of the two NCS(-) ligands.

18.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 1): m174, 2007 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-21200522

RESUMO

The reaction of MgCl(2), NiCl(2), and Na(2)(i-mnt) (i-mnt is 1,1-dicyano-thene-2,2-dithiol-ate) with 15-crown-5 (15-C-5) leads to an infinite chain polymer, {[NiMg(2)(C(4)N(2)S(2))(2)(C(10)H(20)O(5))(2)]Cl(2)}(n) or {[Mg(15-C-5)](2)[Ni(i-mnt)(2)]Cl(2)}(n), which consists of two [Mg(15-C-5)](2+) complex cations, one [Ni(i-mnt)(2)](2-) complex anion and two Cl(-) ions per formula unit. In the [Ni(i-mnt)(2)](2-) complex anion, Ni(2+) is located on a crystallographic mirror plane with a slightly distorted square-planar coordination by four S atoms. In the [Mg(15-C-5)](2+) complex cations, the Mg and one O atom of the crown lie on mirror planes and the Mg atoms are in sevenfold coordination environments of five O atoms from the crown and two N atoms from two i-mnt anions. The bridging of the two complexes via the Mg-N bonds leads to the formation of one-dimensional chains along the a axis.

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