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1.
BMC Med Imaging ; 24(1): 229, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39215218

RESUMEN

OBJECTIVES: To investigate the value of conventional ultrasonography (US) combined with quantitative shear wave elastography (SWE) in evaluating and identifying target axillary lymph node (TALN) for fine needle aspiration biopsy (FNAB) of patients with early breast cancer. MATERIALS AND METHODS: A total of 222 patients with 223 ALNs were prospectively recruited from January 2018 to December 2021. All TALNs were evaluated by US, SWE and subsequently underwent FNAB. The diagnostic performances of US, SWE, UEor (either US or SWE was positive) and UEand (both US and SWE were positive), and FNAB guided by the above four methods for evaluating ALN status were assessed using receiver operator characteristic curve (ROC) analyses. Univariate and multivariate logistic regression analyses used to determine the independent predictors of axillary burden. RESULTS: The area under the ROC curve (AUC) for diagnosing ALNs using conventional US and SWE were 0.69 and 0.66, respectively, with sensitivities of 78.00% and 65.00% and specificities of 60.98% and 66.67%. The combined method, UEor, demonstrated significantly improved sensitivity of 86.00% (p < 0.001 when compared with US and SWE alone). The AUC of the UEor-guided FNAB [0.85 (95% CI, 0.80-0.90)] was significantly higher than that of US-guided FNAB [0.83 (95% CI, 0.78-0.88), p = 0.042], SWE-guided FNAB [0.79 (95% CI, 0.72-0.84), p = 0.001], and UEand-guided FNAB [0.77 (95% CI, 0.71-0.82), p < 0.001]. Multivariate logistic regression showed that FNAB and number of suspicious ALNs were found independent predictors of axillary burden in patients with early breast cancer. CONCLUSION: The UEor had superior sensitivity compared to US or SWE alone in ALN diagnosis. The UEor-guided FNAB achieved a lower false-negative rate compared to FNAB guided solely by US or SWE, which may be a promising tool for the preoperative diagnosis of ALNs in early breast cancer, and had the potential implication for the selection of axillary surgical modality.


Asunto(s)
Axila , Neoplasias de la Mama , Diagnóstico por Imagen de Elasticidad , Ganglios Linfáticos , Humanos , Diagnóstico por Imagen de Elasticidad/métodos , Femenino , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/patología , Neoplasias de la Mama/cirugía , Axila/diagnóstico por imagen , Persona de Mediana Edad , Biopsia con Aguja Fina , Adulto , Anciano , Estudios Prospectivos , Ganglios Linfáticos/diagnóstico por imagen , Ganglios Linfáticos/patología , Sensibilidad y Especificidad , Curva ROC , Metástasis Linfática/diagnóstico por imagen , Biopsia Guiada por Imagen/métodos
2.
BMC Public Health ; 24(1): 1526, 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38844895

RESUMEN

OBJECTIVE: To explore the risk factors for maternal near-miss (MNM) using the WHO near-miss approach. METHODS: Data were obtained from the Maternal Near-Miss Surveillance System in Hunan Province, China, 2012-2022. Multivariate logistic regression analysis (method: Forward, Wald, α = 0.05) and adjusted odds ratios (aORs) were used to identify risk factors for MNM. RESULTS: Our study included 780,359 women with 731,185 live births, a total of 2461 (0.32%) MNMs, 777,846 (99.68%) non-MNMs, and 52 (0.006%) maternal deaths were identified. The MNM ratio was 3.37‰ (95%CI: 3.23-3.50). Coagulation/hematological dysfunction was the most common cause of MNM (75.66%). Results of multivariate logistic regression analysis showed risk factors for MNM: maternal age > = 30 years old (aOR > 1, P < 0.05), unmarried women (aOR = 2.21, 95%CI: 1.71-2.85), number of pregnancies > = 2 (aOR > 1, P < 0.05), nulliparity (aOR = 1.51, 95%CI: 1.32-1.72) or parity > = 3 (aOR = 1.95, 95%CI: 1.50-2.55), prenatal examinations < 5 times (aOR = 1.13, 95%CI: 1.01-1.27), and number of cesarean sections was 1 (aOR = 1.83, 95%CI: 1.64-2.04) or > = 2 (aOR = 2.48, 95%CI: 1.99-3.09). CONCLUSION: The MNM ratio was relatively low in Hunan Province. Advanced maternal age, unmarried status, a high number of pregnancies, nulliparity or high parity, a low number of prenatal examinations, and cesarean sections were risk factors for MNM. Our study is essential for improving the quality of maternal health care and preventing MNM.


Asunto(s)
Potencial Evento Adverso , Humanos , Femenino , China/epidemiología , Factores de Riesgo , Embarazo , Adulto , Potencial Evento Adverso/estadística & datos numéricos , Adulto Joven , Complicaciones del Embarazo/epidemiología , Modelos Logísticos , Mortalidad Materna/tendencias
3.
Gynecol Oncol ; 159(1): 171-178, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32814641

RESUMEN

OBJECTIVE: Artificial intelligence (AI) could automatedly detect abnormalities in digital cytological images, however, the effect in cervical cancer screening is inconclusive. We aim to evaluate the performance of AI-assisted cytology for the detection of histologically cervical intraepithelial lesions (CIN) or cancer. METHODS: We trained a supervised deep learning algorithm based on 188,542 digital cytological images. Between Mar 13, 2017, and Oct 20, 2018, 2145 referral women from organized screening were enrolled in a multicenter, clinical-based, observational study. Cervical specimen was sampled to generate two liquid-based slides: one random slide was allocated to AI-assisted reading, and the other to manual reading conducted by skilled cytologists from senior hospital and cytology doctors from primary hospitals. HPV testing and colposcopy-directed biopsy was performed, and histological result was regarded as reference. We calculated the relative sensitivity and relative specificity of AI-assisted reading compared to manual reading for CIN2+. This trial was registered, number ChiCTR2000034131. RESULTS: In the referral population, AI-assisted reading detected 92.6% of CIN 2 and 96.1% of CIN 3+, significantly higher than or similar to manual reading. AI-assisted reading had equivalent sensitivity (relative sensitivity 1.01, 95%CI, 0.97-1.05) and higher specificity (relative specificity 1.26, 1.20-1.32) compared to skilled cytologists; whereas higher sensitivity (1.12, 1.05-1.20) and specificity (1.36, 1.25-1.48) compared to cytology doctors. In HPV-positive women, AI-assisted reading improved specificity for CIN1 or less at no expense of reduction of sensitivity compared to manual reading. CONCLUSIONS: AI-assisted cytology may contribute to the primary cytology screening or triage. Further studies are needed in general population.


Asunto(s)
Cuello del Útero/patología , Aprendizaje Profundo , Procesamiento de Imagen Asistido por Computador/métodos , Infecciones por Papillomavirus/diagnóstico , Displasia del Cuello del Útero/diagnóstico , Neoplasias del Cuello Uterino/diagnóstico , Adulto , Biopsia , Colposcopía , Conjuntos de Datos como Asunto , Detección Precoz del Cáncer/métodos , Femenino , Humanos , Persona de Mediana Edad , Invasividad Neoplásica , Papillomaviridae/aislamiento & purificación , Infecciones por Papillomavirus/patología , Infecciones por Papillomavirus/virología , Valor Predictivo de las Pruebas , Índice de Severidad de la Enfermedad , Triaje/métodos , Neoplasias del Cuello Uterino/patología , Frotis Vaginal , Displasia del Cuello del Útero/patología , Displasia del Cuello del Útero/virología
4.
Artículo en Inglés | MEDLINE | ID: mdl-36800681

RESUMEN

The cytochrome P450 17α-hydroxylase (P450c17) enzyme, encoded by Cytochrome P450 Family 17 Subfamily A Member 1 (CYP17A1) gene, catalyzes both the 17a-hydroxylation and 17,20-lyase reactions required for the production of cortisol and sex steroids. 17α-hydroxylase/17,20-lyase deficiency (17OHD) is a rare autosomal recessive disease caused by homozygous or compound heterozygous mutations in CYP17A1 gene. 17OHD can be classified into complete form and partial form based on the phenotypes resulting from P450c17 enzyme defects of different severities. Here we report two unrelated girls diagnosed with 17OHD at the age of 15 and 16 respectively. Both patients presented with primary amenorrhea, infantile female external genitalia and absent axillary or pubic hair. Hypergonadotropic hypogonadism was detected in both patients. Besides, Case 1 showed undeveloped breast, primary nocturnal enuresis, hypertension, hypokalemia and reduced 17α-hydroxyprogesterone and cortisol levels, while Case 2 had growth spurt, spontaneous breast development, elevated corticosterone and decreased aldosterone. The chromosome karyotype for both patients was 46, XX. Clinical exome sequencing was used to detect the underlying genetic defect in the patients, and the potential pathogenic mutations were validated by Sanger sequencing of the patients and their parents. The homozygous p.S106P mutation of CYP17A1 gene detected in Case 1 has been reported previously. Although the p.R347C and p.R362H mutations have been reported separately before, their compound heterozygote was firstly identified in Case 2. Based on the clinical, laboratory and genetic findings, Case 1 and Case 2 were definitely diagnosed as complete and partial form of 17OHD respectively. Both patients received estrogen and glucocorticoid replacement therapy. Their uterus and breasts developed gradually, and first menstruation occurred. Hypertension, hypokalemia and nocturnal enuresis in Case 1 were relieved. In conclusion, we described a case of complete 17OHD accompanied by nocturnal enuresis for the first time. Moreover, we identified a new compound heterozygote (p.R347C and p.R362H) of CYP17A1 gene in the case with partial 17OHD.

5.
Front Med (Lausanne) ; 10: 1207248, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37521351

RESUMEN

Objective: To investigate the adverse pregnancy outcomes and associated risk factors among pregnant women with syphilis. Design: Pregnant women with syphilis in the registry for the prevention of mother-to-child transmission of AIDS, syphilis and hepatitis B in Hunan Province, China, from January 1, 2013 to December 31, 2018 were included in the study. Results: Among the 14,219 pregnant women with syphilis, 11,346 had definite pregnancy outcomes and were in singleton pregnancy. The risk factors related to adverse pregnancy outcomes include the age of pregnant women with syphilis <20 years old (aOR = 1.274, 95% CI: 1.088-1.493) or ≥ 35 years old (aOR = 1.402, 95% CI: 1.167-1.686), not married (aOR = 1.855, 95% CI: 1.453-2.367), initial syphilis detection in the late pregnancy (aOR = 1.266, 95% CI: 1.032-1.555), diagnosis of syphilis in the late pregnancy (aOR = 5.806, 95% CI: 1.796-18.770), diagnosis of syphilis during labor (aOR = 4.102, 95% CI: 1.263-13.330), husband/sexual partner infected with syphilis (aOR = 1.222, 95% CI: 1.068-1.398), untreated (aOR = 6.756, 95% CI: 5.586-8.197), and nonstandard medication (aOR = 3.300, 95% CI: 2.841-3.846). Conclusion: The prevalence of adverse pregnancy outcomes among pregnant women with syphilis in Hunan Province, China from 2013 to 2018 was relatively high. The adverse pregnancy outcomes associated with syphilis could be reduced by early detection and standard treatment of syphilis for pregnant women and their husbands/sexual partners.

6.
Front Genet ; 14: 1153960, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37727373

RESUMEN

Insulin resistance plays an important role in the pathogenesis of polycystic ovarian syndrome (PCOS). Calpain10 (CAPN10) gene was the first identified susceptibility gene for type 2 diabetes mellitus and closely related to insulin sensitivity. A lot of research attention has been attracted on the relationship between CAPN10 polymorphisms and PCOS risk, but they didn't reach a consistent conclusion. We therefore performed this systematic review and meta-analysis to assess the association of CAPN10 common variants with PCOS susceptibility. A total of 21 studies were eligible for inclusion. Meta-analyses were done for 5 variants that had at least two data sources: UCSNP-19, -43, -44, -56 and -63. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated under five genetic models. Subgroup analyses by ethnicity, PCOS diagnostic criteria, and source of controls were conducted. Moreover, false-positive report probability (FPRP) test and trial sequential analysis (TSA) were performed to assess the significant associations. The results showed a possible negative association between UCSNP-19 and PCOS risk (ins/ins vs. del/del + del/ins: OR = 0.84, 95% CI: 0.72-0.98). In subgroup analyses, FPRP test indicated that noteworthy associations were observed in mixed ethnicities for UCSNP-43 (A vs. G: OR = 1.81, 95% CI: 1.17-2.79; AA + AG vs. GG: OR = 2.14, 95% CI: 1.20-3.80) and in Asians for UCSNP-44 (CC vs. TT: OR = 2.07, 95% CI: 1.21-3.51; CC vs. CT + TT: OR = 2.19, 95% CI: 1.31-3.69), but TSA plots showed that the accumulated sample sizes of these associations were insufficient to draw firm conclusions. In summary, our study suggested that UCSNP-19, UCSNP-43, and UCSNP-44 in CAPN10 gene may be involved in PCOS susceptibility. These findings warrant further studies.

7.
Exp Gerontol ; 182: 112298, 2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37774893

RESUMEN

Ovarian aging is a significant challenge in gynecology, and there is currently no effective treatment for it. However, the medicinal agent Qingxin Zishen decoction (QZD) has shown potential in the treatment of ovarian dysfunction. The present study aimed to evaluate the mitochondrial apoptotic mechanism of delayed ovarian aging in QZD in aging rats. The healthy female Sprague-Dawley (SD) rats (n = 40, 350 ± 20 g) were randomly assigned to different dosage groups and 4-month-old SD rats (n = 10) were assigned to the control group. QZD groups were treated with QZD for four weeks, and ovarian tissues were extracted for mRNA and protein assays to examine the role of the apoptotic pathway in QZD. The results showed that QZD treatment for four weeks significantly increased the mRNA and protein expressions of the anti-apoptotic gene B-cell lymphoma 2 (Bcl-2) and Bcl-2/Bax ratio, as well as downregulated the pro-apoptotic genes Bax, caspase-3, and caspase-9. Moreover, QZD treatment effectively reduced the expression of cytochrome C (cyto-C) and apoptotic protease-activating factor 1 (Apaf-1), both of which are components of the intrinsic apoptotic pathway. These changes exhibited a dose-response manner. The findings suggest that QZD might have therapeutic potential in delaying ovarian mitochondrial function decline and in preventing and treating ovarian aging-related diseases by downregulating and upregulating the pro-apoptotic (Bax, caspase-3, caspase-9, cyto-C, Apaf-1) and anti-apoptotic (Bcl-2 and Bcl-2/Bax ratio) genes, respectively.

8.
ACS Omega ; 7(9): 8141-8149, 2022 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-35284717

RESUMEN

Silver complexes with proteinogenic amino acid ligands are of interest for biomedical and antimicrobial applications. In this work, we obtained {[Ag7(l-his)4](NO3)3·3H2O}0.2{[Ag8(l-his)4(H2O)2](NO3)4·3H2O}0.8 (1) and {[Ag7(d-his)4](NO3)3·3H2O}0.2{[Ag8(d-his)4(H2O)2](NO3)4·3H2O}0.8 (2), which represent the first example of any Ag-exclusive complex featuring a cluster-type core motif and with only proteinogenic amino acid ligands. Upon immersion into acetonitrile, an interesting single-crystal-to-single-crystal transformation occurred to produce a new cluster complex of the formula [Ag8(l-his)4(NO3)(H2O)](NO3)3 (3). Using a racemic mixture of histidine, the reaction under otherwise identical conditions led to the production of the second example of a three-dimensional (3D) network structured Ag-exclusive complex with only a proteinogenic amino acid ligand. Compared with other Ag-histidine complexes in the literature, the significance of reaction conditions, particularly the Ag/histidine ratio and pH of the reaction mixture, is revealed. Temperature-dependent emission of 1 and 2 at 440 nm characteristic of silver-philophilic interactions was also observed.

9.
Infect Dis Poverty ; 10(1): 37, 2021 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-33761984

RESUMEN

BACKGROUND: The COVID-19 has caused significant toll over the globe. Pregnant women are at risk of infection. The present study examined the frequency of washing hands with soap and wearing face mask when going out, prevalence of depression and anxiety, and identified their associated factors among pregnant women during the early phase of COVID-19 outbreak in China. METHODS: A cross-sectional online survey was conducted between 24 February and 3 March 2020. A total of 15 428 pregnant women who were using maternal health care services in China completed a questionnaire which assessed their socio-demographic and pregnancy-related characteristics, contextual, cognitive and social factors related to COVID-19, frequency of washing hands and wearing face masks, and depression and anxiety. Logistics regression analyses were performed to identify the associated factors of preventive behaviours and mental health. RESULTS: The prevalence of probable anxiety and depression was 28.2% and 43.6% respectively. 19.8% reported always wearing face mask when going out, and 19.1% reported washing hands with soap for more than 10 times per day. Results from logistic regression analyses showed that older age was associated with lower levels of depression and anxiety (OR = 0.42-0.67) and higher frequency of washing hands (OR = 1.57-3.40). Higher level of education level was associated with probable depression (OR = 1.31-1.45) and higher frequency of wearing face mask (OR = 1.50-1.57). After adjusting for significant socio-demographic and pregnancy-related factors, place of residence being locked down (aOR = 1.10-1.11), being quarantined (aOR = 1.42-1.57), personally knowing someone being infected with COVID-19 (aOR = 1.80-1.92), perception that COVID-19 would pose long term physical harm to human (aOR = 1.25-1.28) were associated with higher levels of depression and anxiety, while the perception that the disease will be under control in the coming month was associated with lower levels of depression and anxiety (aOR = 0.59-0.63) and lower tendency of always wearing face mask (aOR = 0.85). Social support was associated with lower levels of depression and anxiety (aOR = 0.86-0,87) and higher frequency of washing hands (aOR = 1.06). CONCLUSIONS: The mental health and preventive behaviours of pregnant women during COVID-19 outbreak was associated with a range of socio-demographic, pregnancy-related, contextual, cognitive and social factors. Interventions to mitigate their mental health problems and to promote preventive behaviours are highly warranted.


Asunto(s)
COVID-19/prevención & control , COVID-19/psicología , Conductas Relacionadas con la Salud , Salud Mental , Complicaciones Infecciosas del Embarazo/prevención & control , SARS-CoV-2 , Adulto , Factores de Edad , China , Depresión/epidemiología , Escolaridad , Femenino , Desinfección de las Manos/tendencias , Humanos , Modelos Logísticos , Servicios de Salud Materna/estadística & datos numéricos , Oportunidad Relativa , Equipo de Protección Personal , Embarazo , Complicaciones Infecciosas del Embarazo/psicología , Atención Prenatal , Prevalencia , Factores de Riesgo , Apoyo Social , Encuestas y Cuestionarios , Adulto Joven
10.
J Affect Disord ; 275: 149-156, 2020 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-32734901

RESUMEN

BACKGROUND: Few studies explored trajectories of depressive symptoms from early pregnancy and covered the whole perinatal period. This study aimed to explore the trajectories of perinatal depressive symptoms, their heterogeneity of onsets and peaks, and relations to demographic and psychological factors. METHOD: A longitudinal study was conducted at two hospitals in China amongst 1,126 participants. Perinatal depression was measured using the Edinburgh Postnatal Depression Scale. Demographic and psychological factors were collected by self-developed questionnaire and Generalized Anxiety Disorder-7. Women completing at least three depression screens (n = 879) were included. Latent Growth Curve Model and Growth Mixture Model were performed to identify the depression trajectories and logistic regression was used to analyse factors of trajectories. RESULTS: Three trajectories were identified: 90.0% of women never presented with depressive symptoms ("Low-throughout"); 5.1% presented with depressive symptoms mainly during the antenatal period ("Antenatal-high"); 4.9% presented with depressive symptoms mainly during the postpartum period ("Postpartum-high"). 52.4% of women experienced their first depressive symptoms during early pregnancy. Suffering from anxiety and being unsatisfied with their marriage were associated with the "Antenatal-high" and "Postpartum-high" trajectories, respectively. LIMITATIONS: Response rate was not high. We also do not have information on clinical diagnoses or changes in some variables over time. CONCLUSIONS: We identified three trajectories and heterogeneity existed concerning the timing of their peaks. Women should be considered for depression screening and intervention in early pregnancy. Factors associated with each trajectory were different, raising the potential of individualized intervention to reduce the occurrence of depression.


Asunto(s)
Depresión Posparto , Complicaciones del Embarazo , China , Depresión/diagnóstico , Depresión/epidemiología , Depresión Posparto/diagnóstico , Depresión Posparto/epidemiología , Femenino , Humanos , Estudios Longitudinales , Periodo Posparto , Embarazo , Complicaciones del Embarazo/epidemiología , Factores de Riesgo
11.
J Am Chem Soc ; 131(20): 6918-9, 2009 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-19397326

RESUMEN

A chiral, cagelike, high-nuclearity lanthanide hydroxide cluster containing 60 Er(III) ions is reported. The cluster core possesses a fascinating sodalite-like structure with 24 vertex-sharing cubane-like [Er(4)(mu(3)-OH)(4)](8+) units. The hexagonal face of the sodalite cage features a templating mu(6)-CO(3)(2-) ion. Magnetic studies revealed weak antiferromagnetic interactions.

12.
Women Birth ; 32(6): 570-578, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30497906

RESUMEN

BACKGROUND: China is the first country to initiate a nationwide program for prevention of mother-to-child transmission of human immunodeficiency virus, syphilis and hepatitis B virus by an integrated approach. However, the progress of this program remains unreported at national or local level for China. Therefore, we performed a hospital-based longitudinal study to assess the integrated prevention effect in Hunan, South-central China. METHODS: This study was conducted at 123 counties in Hunan and covered all local hospitals providing midwifery and antenatal care services from 2010 to 2016. We used the Cochran-Armitage test to examine the temporal changes of the indicators related with prevention of mother-to-child transmission. Besides, we used Spearman rank correlation analysis to assess the association between mother-to-child transmission rates and the process indicators related with prevention of mother-to-child transmission. RESULTS: After implementation of integrated prevention program, the indicators related with prevention of mother-to-child transmission are moving in the right direction. From 2010 to 2016, mother-to-child transmission rates significantly decreased from 19.4% to 9.6% for human immunodeficiency virus, and from 116.3 to 13.6 cases per 100,000 live births for syphilis. The proportion of children receiving hepatitis B immunoglobulin injection within 24h after birth increased from 95.2% to 98.9% among exposed neonates. Mother-to-child transmission rates were negatively associated with the process indicators related with prevention of mother-to-child transmission (all P<0.05). CONCLUSIONS: Our prevention program of mother-to-child transmission for three diseases by an integrated approach proved to be viable and effective. Our model may be of interest to other countries.


Asunto(s)
Infecciones por VIH/transmisión , Hepatitis B/transmisión , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Complicaciones Infecciosas del Embarazo/microbiología , Sífilis/transmisión , Adulto , China , Femenino , VIH , Virus de la Hepatitis B , Humanos , Lactante , Recién Nacido , Estudios Longitudinales , Embarazo , Atención Prenatal , Evaluación de Programas y Proyectos de Salud
13.
Appl Opt ; 47(28): 5074-7, 2008 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-18830292

RESUMEN

We measured transient photoinduced birefringence (delta n) in various azobenzene dye films by pumping with a nanosecond pulse at 532 nm and probing at 633 nm. The switch-on times for the photoinduced birefringence range from nanoseconds to milliseconds and are systematically related with the lowest optical transition energies for those films. Moreover, our results suggest that the transient photoinduced birefringence measurement is a convenient way to determine the relative energies of pi-pi(*) and n-pi(*) states in azo-based materials.

14.
Dalton Trans ; 40(5): 1041-6, 2011 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-21152668

RESUMEN

Lanthanide hydroxide cluster complexes with acetylacetonate were synthesized by the hydrolysis of the corresponding hydrated lanthanide acetylacetonates in methanol in the presence of triethylamine. Polymeric lanthanide hydroxide complexes based on diamond-shaped dinuclear repeating units of [Ln(2)(CH(3)CO(3))(2)](4+) (Ln = La, Pr) and discrete complexes featuring a tetranuclear distorted cubane core of [Ln(4)(µ(3)-OH)(2)(µ(3)-OCH(3))(2)](8+) (Ln = Nd, Sm) and a nonanuclear core of [Ln(9)(µ(4)-O)(µ(4)-OH)(µ(3)-OH)(8)](16+) (Ln = Eu-Dy, Er, Yb) were obtained. The dependence of the cluster nuclearity on the identity of the lanthanide ion is rationalized in terms of the influences of a metal ion's Lewis acidity and the sterics about the Ln-OH unit on the kinetics of the assembly process that leads to a particular cluster.

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