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1.
Inorg Chem ; 62(37): 14863-14872, 2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37676750

RESUMO

Cooperative spin crossover transitions with thermal hysteresis loops are rarely observed in cobalt(II) complexes. Herein, two new mononuclear cobalt(II) complexes with hysteretic spin crossover at relatively high temperatures (from 320 to 400 K), namely, [Co(terpy-CH2OH)2]·X2 (terpy-CH2OH = 4'-(hydroxymethyl)-2,2';6',2″-terpyridine, X = SCN-(1) and SeCN- (2)), have been synthesized and characterized structurally and magnetically. Both compounds are mononuclear CoII complexes with two chelating terpy-CH2OH ligands. Magnetic measurements revealed the existence of the hysteretic SCO transitions for both complexes. For compound 1, a one-step transition with T1/2↑= 334.5 K was observed upon heating, while a two-step transition is observed upon cooling with T1/2↓(1) = 329.3 K and T1/2↓(2) = 324.1 K (at a temperature sweep rate of 5 K/min). As for compound 2, a hysteresis loop with a width of 5 K (T1/2↓ = 391.6 K and T1/2↑ = 396.6 K, at a sweep rate of 5 K/min) can be observed. Thanks to the absence of the crystallized lattice solvents, their single crystals are stable enough at high temperatures for the structure determination at both spin states, which reveals that the hysteretic SCO transitions in both complexes originate from the crystallographic phase transitions involving a thermally induced order-disorder transition of the dangling -CH2OH groups in the ligand. This work shows that the modification of the terpy ligand has an important effect on the magnetic properties of the resulting cobalt(II) complexes.

2.
Inorg Chem ; 62(38): 15465-15478, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37699414

RESUMO

Three new cyano-bridged FeII-MoIII complexes assembled from the [MoIII(CN)7]4- unit, FeII ions, and three pentadentate N3O2 ligands, namely {[Fe2H3(dapab)2][Mo(CN)6]}n·2H2O·3.5MeCN (1), [Fe(H2dapb)(H2O)][Fe(Hdapb)(H2O)][Mo(CN)6]·4H2O·3MeCN (2), and [Fe(H2dapba)(H2O)]2[Mo(CN)7]·6H2O (3) (H2dapab = 2,6-diacetylpyridine bis(2-aminobenzoylhydrazone), H2dapb = 2,6-diacetylpyridine bis(benzoylhydrazone), H2dapba = 2,6-diacetylpyridine bis(4-aminobenzoylhydrazone)), have been synthesized and characterized. Single-crystal structure analyses suggest that complex 1 contains a one-dimensional (1D) chain structure where two FeII ions are bridged by the in situ generated [MoIII(CN)6]3- unit through two trans-cyanide groups into trinuclear Fe2IIMoIII clusters that are further linked by the amino of the ligand into an infinite chain. Complexes 2 and 3 are cyano-bridged Fe2IIMoIII trinuclear clusters with two FeII ions connected by the [MoIII(CN)6]3- and [MoIII(CN)7]4- units, respectively. Direct current magnetic studies confirmed the ferromagnetic interactions between the cyano-bridged FeII and MoIII centers and significant easy-axis magnetic anisotropy for all three complexes. Furthermore, complexes 1-3 exhibit slow magnetic relaxation under a zero dc field, with relaxation barriers of 42.3, 21.6, and 14.4 K, respectively, making them the first examples of cyano-bridged FeII-MoIII single-molecule magnets.

3.
IUBMB Life ; 72(8): 1686-1697, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32311821

RESUMO

microRNA-3607 (miR-3607) has been identified as an important biomarker, and its aberrant expression exerts a significant role in tumorigenesis. However, the biological function of miR-3607 in hepatocellular carcinoma (HCC) needs to be deciphered comprehensively. Clinical samples of HCC patients, as well as normal cases, were derived from The Cancer Genome Atlas database. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) and Western blotting analyses were utilized to detect the expression levels of indicated genes. Cell counting kit-8 (CCK-8), colony formation, and transwell assays were performed to assess the effect of miR-3607 in HCC cell viability, migration, and invasion. Bioinformatics analysis and luciferase reporter gene assay was applied to screen the target genes of miR-3607 and verified the association between miR-3607 and its potential target gene. Our study showed that miR-3607 expression was decreased in HCC tissues and cell lines, and its downregulation was linked with poor outcomes of HCC patients. miR-3607 was noted to inhibit HCC cell growth, colony formation, migration, and invasion. Besides, minichromosome maintenance (MCM5) was a possible target gene of miR-3607 in HCC. Overexpression of MCM5 was observed in HCC and induced unfavorable prognosis. MCM5 expression had a negative correlation with miR-3607. MCM5 can abolish the suppressive impacts of miR-3607 on HCC cell malignant behaviors and the epithelial-mesenchymal transition (EMT) process. To sum up, our results unveiled that miR-3607 could inhibit HCC cell growth, migration, and invasion by regulating MCM5 and mediating EMT process, suggesting a new probable biomarker for further treatment of HCC.


Assuntos
Carcinoma Hepatocelular/genética , Proteínas de Ciclo Celular/genética , Neoplasias Hepáticas/genética , MicroRNAs/genética , Idoso , Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/patologia , Movimento Celular/genética , Transição Epitelial-Mesenquimal/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Células Hep G2 , Humanos , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Prognóstico
4.
Zhongguo Dang Dai Er Ke Za Zhi ; 21(9): 910-914, 2019 Sep.
Artigo em Zh | MEDLINE | ID: mdl-31506152

RESUMO

OBJECTIVE: To study the relationship between serum microRNA-122 (miR-122) and insulin resistance in obese children. METHODS: Forty-seven children with severely obesity aged 7-14 years and 45 age- and gender matched healthy children with normal weight (control group) were enrolled. The levels of height, weight, waistline, hip circumference, fasting blood glucose (FBG), fasting insulin (FINS), triglyceride (TG), total cholesterol (TC), free fatty acid (FFA), interleukin-6 (IL-6) and miR-122 in the two groups were measured. Body mass index (BMI), waist-hip ratio (WHR) and insulin resistance index (HOMA-IR) were calculated. RESULTS: Compared with the control group, the height, weight, BMI, WHR, FINS, HOMA-IR, TG, FFA, IL-6, and miR-122 levels in the obese group were significantly increased (P<0.05). MiR-122 levels in the obese group were positively correlated with FINS, HOMA-IR and IL-6 levels (r=0.408, 0.442, and 0.464 respectively, P<0.05). The changes of miR-122 have a linear regression relationship with IL-6 (b'=0.318, P<0.05). CONCLUSIONS: The elevated serum miR-122 levels may be correlated with insulin resistance in obese children. The mechanism needs to be further studied.


Assuntos
Resistência à Insulina , MicroRNAs/genética , Adolescente , Glicemia , Índice de Massa Corporal , Criança , Humanos , Insulina , Obesidade , Relação Cintura-Quadril
5.
Zhongguo Dang Dai Er Ke Za Zhi ; 20(12): 1020-1023, 2018 Dec.
Artigo em Zh | MEDLINE | ID: mdl-30572991

RESUMO

OBJECTIVE: To study the protective effect of vitamin A on residual pancreatic ß cell function in children with type 1 diabetes mellitus (T1DM) and its mechanism. METHODS: A total of 46 children with T1DM (with a course of disease of 0.5-1 year) were randomly divided into an intervention group and a non-intervention group (n=23 each). The children in both groups were given insulin treatment, and those in the intervention group were also given vitamin A at a daily dose of 1 500-2 000 IU. A total of 25 healthy children were enrolled as the control group. The daily dose of insulin was calculated for the children with T1DM, and the serum levels of glycosylated hemoglobin (HbA1C), stimulated C-peptide, vitamin A, and interleukin-17 (IL-17) were measured before intervention and 3 months after intervention. RESULTS: Before vitamin A intervention, the intervention group and the non-intervention group had a significantly lower serum level of vitamin A and a significantly higher level of IL-17 than the control group (P<0.01). After 3 months of intervention, the intervention group had significantly lower serum IL-17 level and insulin dose and a significantly higher level of stimulated C-peptide than the non-intervention group (P<0.05). CONCLUSIONS: Vitamin A may protect residual pancreatic ß cell function, possibly by improving the abnormal secretion of IL-17 in children with T1DM.


Assuntos
Diabetes Mellitus Tipo 1 , Células Secretoras de Insulina , Glicemia , Peptídeo C , Hemoglobinas Glicadas , Humanos , Lactente , Insulina , Vitamina A
6.
Proc Natl Acad Sci U S A ; 111(35): 12936-41, 2014 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-25114214

RESUMO

It has long been observed that rare earth elements (REEs) regulate multiple facets of plant growth and development. However, the underlying mechanisms remain largely unclear. Here, using electron microscopic autoradiography, we show the life cycle of a light REE (lanthanum) and a heavy REE (terbium) in horseradish leaf cells. Our data indicate that REEs were first anchored on the plasma membrane in the form of nanoscale particles, and then entered the cells by endocytosis. Consistently, REEs activated endocytosis in plant cells, which may be the cellular basis of REE actions in plants. Moreover, we discovered that a portion of REEs was successively released into the cytoplasm, self-assembled to form nanoscale clusters, and finally deposited in horseradish leaf cells. Taken together, our data reveal the life cycle of REEs and their cellular behaviors in plant cells, which shed light on the cellular mechanisms of REE actions in living organisms.


Assuntos
Armoracia/metabolismo , Endocitose/fisiologia , Metais Terras Raras/metabolismo , Desenvolvimento Vegetal/fisiologia , Vesículas Transportadoras/metabolismo , Armoracia/crescimento & desenvolvimento , Flores/metabolismo , Lantânio/metabolismo , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Radioisótopos , Solo , Térbio/metabolismo
7.
Biomed Environ Sci ; 30(11): 792-801, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29216956

RESUMO

OBJECTIVE: This study aimed to investigate the susceptibility of mice with streptozotocin(STZ)-induced diabetes mellitus (TIDM) to the uptake of pentavalent inorganic arsenic (iAsV) and the possible molecular mechanism. METHODS: TIDM was induced in mice by STZ. TIDM and normal mice were treated with 15.0 mg/kg Na2HAsO4·12H2O by intragastric administration. Then, the concentrations of arsenic in various tissues were measured by atomic fluorescence spectrometry. The gene expression levels of Pit1 and Pit2 were quantified by real-time RT-PCR, and their protein levels were detected by Western blotting in mouse heart, kidney, and liver tissues. RESULTS: The concentrations of arsenic in STZ-induced TIDM mouse tissues were higher at 2 h after intragastric administration of Na2HAsO4·12H2O. Compared with the levels in normal mice, PIT1 and PIT2, which play a role in the uptake of iAsV, were upregulated in the livers and hearts of TIDM mice. PIT1 but not PIT2 was higher in TIDM mouse kidneys. The upregulation of Pit1 and Pit2 expression could be reversed by insulin treatment. CONCLUSION: The increased uptake of iAsV in TIDM mouse tissues may be associated with increased PIT1 and/or PIT2 expression.


Assuntos
Arsênio/farmacocinética , Diabetes Mellitus Experimental/metabolismo , Poluentes Ambientais/farmacocinética , Regulação da Expressão Gênica/fisiologia , Proteínas Cotransportadoras de Sódio-Fosfato Tipo III/metabolismo , Fator de Transcrição Pit-1/metabolismo , Animais , Masculino , Camundongos , Camundongos Endogâmicos ICR , Proteínas Cotransportadoras de Sódio-Fosfato Tipo III/genética , Fator de Transcrição Pit-1/genética
8.
Tumour Biol ; 37(8): 10861-70, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26883251

RESUMO

We aimed to investigate the role of large intergenic noncoding RNA regulator of reprogramming (linc-ROR) in the chemotherapy resistance of human breast cancer (BC) cells and its mechanism. A total of 142 patients diagnosed with BC in the First Affiliated Hospital, Zhejiang University between January 2012 and January 2014 were enrolled in our study. The BC tissues and the adjacent normal tissues (5 cm away from tumor tissue) of the enrolled patients were selected, and human BC cell lines (MCF10A, SK-BR-3, MCF-7, Bcap-37, MDA-MB-231, and T47D) were also selected. Quantitative real-time polymerase chain reaction (qRT-PCR), Western blot, 3-(4, 5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, inner salt (MTS) assay, and Transwell were applied in our study. Expression level of linc-ROR messenger RNA (mRNA) in BC tissues was clearly higher than that in adjacent normal tissues, and significant difference was found between expression level of linc-ROR mRNA and lymph node metastasis (all P < 0.05). Linc-ROR was highly expressed in others BC cell lines compared with that in immortalized mammary epithelial cells (MECs) MCF10A (both P < 0.05), while MDA-MB231 cell presented the higher expression (P < 0.001). Under different concentrations of 5-FU and paclitaxel in MDA-MB231 cell, E-cadherin mRNA and protein expressions increased gradually with the increase of concentrations, and Vimentin and N-cadherin mRNA and protein expressions decreased gradually with the decrease of concentrations (all P < 0.05). Compared with shCtrl group, MDA-MB231 cell in shROR group presented higher sensibility of 5-FU and paclitaxel with increased E-cadherin expression, decreased Vimentin and N-cadherin expression and invasion ability (all P < 0.05). Compared with vector cell, overexpressed linc-ROR cell presented decreased sensibility of 5-FU and paclitaxel with decreased E-cadherin expression, increased Vimentin, N-cadherin expression, and invasion ability (all P < 0.05). Our study demonstrated that linc-ROR is an important marker for multidrug resistance of BC, and its up-regulation is important for chemotherapy tolerance and invasion of BC.


Assuntos
Neoplasias da Mama/patologia , Resistencia a Medicamentos Antineoplásicos/genética , Transição Epitelial-Mesenquimal/genética , Invasividade Neoplásica/genética , RNA Longo não Codificante/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Western Blotting , Neoplasias da Mama/genética , Feminino , Técnicas de Silenciamento de Genes , Humanos , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo Real
9.
Inorg Chem ; 55(11): 5107-9, 2016 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-27177390

RESUMO

Self-assembly of the [Mo(III)(CN)7](4-) anion and the Mn(II) unit with a macrocyclic ligand results in the first example of a one-dimensional (1D) chain compound based on the heptacyanomolybdate, [Mn(LN5C10)]2[Mo(CN)7]·2H2O (LN5C10 = 1,4,7,10,13-pentaazacyclopentadecane). Because of the existence of the interchain magnetic coupling, long-rang magnetic ordering was observed in this compound.

10.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 44(5): 532-8, 2015 09.
Artigo em Zh | MEDLINE | ID: mdl-26713528

RESUMO

OBJECTIVE: To investigate the effects of ulinastatin(UTI) on postoperative cognitive function in patients undergoing coronary artery bypass grafting. METHODS: One hundred and twenty-seven patients undergoing elective coronary artery bypass surgery were randomly divided into three groups:high-dose UTI group(16000 U/kg i.v.), low-dose UTI group(8000 U/kg i.v.) and control group(normal saline). The levels of plasma cortisol were measured before and one day after surgery. The level of IL-6, IL-10, TNF-α and S100ß were measured before operation(T0), at open chest(T1), end of operation(T2), 6 h(T3)and 24 h(T4) after operation. A neuropsychological test scale was to evaluate the cognitive function 1 day before operation, 1 week and 3 months after operation. RESULTS: Ninety-three patients completed the study. There was no significant difference in general information of patients among three groups(P>0.05). The level of plasma cortisol one day after operation was significantly higher than that before operation in control group(P<0.01). The levels of plasma cortisol in high-dose UTI group and low-dose UTI group were lower than that of control group(P<0.01). In all groups, the level of plasma IL-6, IL-10, TNF-α and S100B increased remarkably at T2, T3, T4 compared to those at T0(all P<0.05). The level of plasma IL-6, TNF-α(at T2, T3, T4)and S100ß(at T3)in high-dose UTI group and low-dose UTI group were all lower than those of control group(P<0.05),while there were no significant differences between high-dose UTI group and low-dose UTI group(P>0.05). The incidence of postoperative cognitive dysfunction in POCD 1 week after operation in high-dose UTI and low-dose UTI groups(25.8% and 23.3%)was lower than that in control group(50.0%), while there were no significant difference 1 month after operation between high-dose UTI group(12.9%) or low-dose UTI group(16.7%)and control group(28.1%). The level of plasma S100ß at T2 of POCD patients(n=31)was higher than that of non-POCD group(n=62)(P<0.05). CONCLUSION: Ulinastatin can reduce the incidence of postoperative cognitive dusfunction 1 week after coronary artery bypass surgery, which might be associated with inhibition of inflammation and S100ß expression.


Assuntos
Cognição/efeitos dos fármacos , Ponte de Artéria Coronária , Glicoproteínas/uso terapêutico , Humanos , Inflamação/tratamento farmacológico , Interleucina-10/sangue , Interleucina-6/sangue , Complicações Pós-Operatórias/prevenção & controle , Subunidade beta da Proteína Ligante de Cálcio S100/sangue , Fator de Necrose Tumoral alfa/sangue
11.
Zhong Yao Cai ; 38(7): 1370-4, 2015 Jul.
Artigo em Zh | MEDLINE | ID: mdl-26946832

RESUMO

OBJECTIVE: To study the potential ecological suitability regionalization of Angelica sinensis, for protecting wild resources and selecting cultivation location and designing rational production layout. METHODS: Based on fuzzy matter element model, the relationship of fuzzy membership function between ferulic acid content and 14 ecological factors, including climate, topography and soil,were established. Then information entropy theory was used to determine the relative importance of each environmental factor, and thus to determine the most limiting habitat criteria. Finally, the probable spatial distribution of Angelica sinensis across ten provinces in Western China was determined based on GIS spatial analysis of habitat conditions. Meanwhile, the optimal index range of ecological factors was quantified. RESULTS: It was showed that the percentage of moderately and highly suitable habitats for Angelica sinensis in the study area was 9. 64%, its area was 306,768. 01 km2. The moderately and highly suitable habitats were mainly located in the southeast of Gansu ind Tibet,the north of Sichuan and the northwest of Yunnan. The results also showed that six dominant ecological factors controlling the distribution of Angelica sinensis. These six dominant features were as follows: (1) mean temperature of wettest quarter, (2) altitude, (3) precipitation of growth, (4) annual relative humidity, (5) average temperature of growth period, and (6) annual )recipitation. CONCLUSION: The habitat suitability assessment model based on GIS and fuzzy matter element model theory can accurately valuate the habitat suitability of Angelica sinensis, quantify the area of suitable habitat and analyze the spatial distribution. This informaion is of value to provide insight for choosing the most suitable cultivation sites,as well as the habitat protection zones.


Assuntos
Angelica sinensis/crescimento & desenvolvimento , Ecossistema , Modelos Teóricos , Altitude , China , Clima , Sistemas de Informação Geográfica , Plantas Medicinais/crescimento & desenvolvimento , Solo , Temperatura , Tibet
12.
Zhongguo Dang Dai Er Ke Za Zhi ; 17(1): 72-6, 2015 Jan.
Artigo em Zh | MEDLINE | ID: mdl-25616298

RESUMO

OBJECTIVE: To evaluate the current status of penis and testicular development in boys and the effects of overweight/obesity on their development in the Zhengzhou area of Henan Province. METHODS: Height, weight, waist circumference, hip circumference, penis length and testicular volume were measured in 3 546 4 to 12-year-old boys. The penis length and testicular volume were compared between the overweight/obesity and normal weight groups. RESULTS: Before 9 years of age, the testicular volume was progressively smaller, and after 9 years old, it gradually increased. By the age of 11, it increased rapidly. The penis length increased gradually between 4 and 11 years of age, and after the age of 11 it increased rapidly. Phimosis was found in 144 cases (4.01%) and cryptorchidism was found in 18 cases (0.51%). A total of 639 (18.02%) boys were overweight or obese among 3 546 boys. At the ages of 6 and 7 years, the testicular volume in the overweight/obesity group was greater than in the normal control group (P<0.05). The penis length in the overweight/obesity group was significantly shorter than in the normal control group (P<0.05) by the age of 11 years. The correlation analysis showed that the testicular volume at the ages of 4 and 5 years was positively correlated with height, weight, BMI, waist circumference and hip circumference in overweight/obese boys. The penis length at the ages of 7 and 8 years was negatively correlated with weight, waist circumference and hip circumference. By the age of 12 years, the penis length was positively correlated with the height. CONCLUSIONS: The development of penis and testicles in boys in the Zhengzhou area is in line with the level of sex development of Chinese boys. Overweight/obesity adversely affects the development of penis and testicles.


Assuntos
Obesidade/fisiopatologia , Sobrepeso/fisiopatologia , Pênis/crescimento & desenvolvimento , Testículo/crescimento & desenvolvimento , Criança , Pré-Escolar , China , Humanos , Masculino , Obesidade/epidemiologia , Sobrepeso/epidemiologia
13.
ACS Appl Mater Interfaces ; 16(25): 32847-32856, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38862405

RESUMO

Controlling the crystal facets of semiconductor nanocrystals (NCs) has been proven as an effective approach to tune their physicochemical properties. However, the study on facet-engineering of metastable zinc blende CdS (zb-CdS) and its heterostructures is still not fully explored. In this study, the zb-CdS and Au@zb-CdS core-shell NCs with tunable terminating facets are controllably synthesized, and their photocatalytic performance for water splitting are evaluated. It is found that the {111} facets of the zb-CdS NCs display higher intrinsic activity than the {100} counterparts, which originates from these surfaces being much more efficient, facilitating electron transition to enhance the adsorption ability and the dissociation of the adsorbed water, as revealed by theoretical calculations. Moreover, the Au@zb-CdS core-shell NCs exhibit better photocatalytic performance than the zb-CdS NCs terminated with the same facets under visible light irradiation (≥400 nm), which is mainly ascribed to the accelerated electron separation at the interface, as demonstrated by femtosecond transient absorption (fs-TA) spectroscopy. Importantly, the quantum yield of plasmon-induced hot electron transfer quantified by fs-TA in the Au@zb-CdS core-shell octahedrons can be reached as high as 1.2% under 615 nm excitation, which is higher than that of the Au@zb-CdS core-shell cubes. This work unravels the face-dependent photocatalytic performance of the metastable semiconductor NCs via a combination of experiments and theoretical calculations, providing the understanding of the underlying mechanism of these photocatalysts.

14.
J Am Chem Soc ; 135(43): 16006-9, 2013 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-24131156

RESUMO

A series of end-to-end azido-bridged perovskite-type compounds [(CH3)nNH4-n][Mn(N3)3] (n = 1-4) were synthesized and characterized. Structural phase transitions indicating the general lattice flexibility were observed and confirmed by the crystal structures of different phases. These materials show cation-dependent magnetic ordering at up to 92 K and magnetic bistability near room temperature.


Assuntos
Azidas/química , Compostos de Cálcio/química , Cátions/química , Óxidos/química , Titânio/química , Azidas/síntese química , Hidrocarbonetos Aromáticos com Pontes , Compostos de Cálcio/síntese química , Varredura Diferencial de Calorimetria , Cristalografia por Raios X , Estabilidade de Medicamentos , Campos Magnéticos , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Conformação Molecular , Óxidos/síntese química , Temperatura
15.
Inorg Chem ; 52(13): 7314-6, 2013 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-23746362

RESUMO

Four tetranuclear 3d-4f complexes with the 4f centers bridged solely by end-on azide bridges were reported. The [CuTb]2 compound displays single-molecule-magnet behavior with hysteresis loops observed at up to 2.4 K.

16.
Int J Clin Pharmacol Ther ; 51(8): 615-9, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23782580

RESUMO

OBJECTIVE: This study aimed to test the effects of hypophysin on hemodynamics and coronary artery caliber of patients with hypotension and decreased systemic vascular resistance (SVR) following cardiopulmonary bypass (CPB). METHODS: Twenty-four patients with mean arterial pressure (MAP) < 60 mmHg, mean aorta pressure < 70 mmHg, SVR < 800 dynes.sec.cm-5, cardiac index (CI) > 2.5 l.min-1.m-2, central venous pressure > 8 mmHg and refractory to dopamine, norepinephrine, and fluid resuscitation were treated with hypophysin at an initial dose of 0.6 IU and a continuous infusion rate of 1 - 4 IU/h till the end of operation. The hemodynamics and the diameter of proximal left main coronary artery were evaluated before incision, before hypophysin administration, 5 min after hypophysin administration, and at the end of operation. RESULTS: MAP, SVR, and the diameter of proximal left main coronary artery increased whereas heart rate, CI, stroke volume index, and mean pulmonary artery pressure had no significant changes after hypophysin administration compared with before hypophysin administration. All hypophysin-treated patients successfully recovered. CONCLUSION: Hypophysin may improve the hemodynamics and dilate the proximal left main coronary artery in hypotensive patients with low SVR following CPB.


Assuntos
Ponte Cardiopulmonar/efeitos adversos , Hipotensão/tratamento farmacológico , Hormônios Neuro-Hipofisários/uso terapêutico , Resistência Vascular/efeitos dos fármacos , Adulto , Idoso , Pressão Arterial/efeitos dos fármacos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
17.
Biomed Environ Sci ; 26(2): 148-54, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23336138

RESUMO

OBJECTIVE: To isolate and characterize indigenous algicidal bacteria and their algae-lysing compounds active against Microcystis aeruginosa, strains TH1, TH2, and FACHB 905. METHODS: The bacteria were identified using the Biolog automated microbial identification system and 16S rDNA sequence analysis. The algae-lysing compounds were isolated and purified by silica gel column chromatography and reverse-phase high performance liquid chromatography. Their structures were confirmed by Nuclear Magnetic Resonance (NMR) and Fourier Transform Infrared (FT-IR) spectroscopy. Algae-lysing activity was observed using microscopy. RESULTS: The algae-lysing bacterium LTH-2 isolated from Lake Taihu was identified as Serratia marcescens. Strain LTH-2 secreted a red pigment identified as prodigiosin (C20H25N3O), which showed strong lytic activity with algal strains M. aeruginosa TH1, TH2, and FACHB 905 in a concentration-dependent manner. The 50% inhibitory concentration (IC50) of prodigiosin with the algal strains was 4.8 (± 0.4)× 10⁻² µg/mL, 8.9 (± 1.1)× 10⁻² µg/mL, and 1.7 (± 0.1)× 10⁻¹ µg/mL in 24 h, respectively. CONCLUSION: The bacterium LTH-2 and its pigment had strong Microcystis-lysing activity probably related to damage of cell membranes. The bacterium LTH-2 and its red pigment are potentially useful for regulating blooms of harmful M. aeruginosa.


Assuntos
Antibacterianos/farmacologia , Bactérias/metabolismo , Microcystis/crescimento & desenvolvimento , Bactérias/classificação , Bactérias/genética , Lagos , Filogenia
18.
Dalton Trans ; 52(26): 8964-8974, 2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37326416

RESUMO

A novel bis-bidentate nitronyl nitroxide radical based on triazolopyrimidine, NIT-2-TrzPm (NIT-2-TrzPm = (2-(2'-triazolopyrimidine)-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazol-1-oxy-3-oxide)) and six new transition metal complexes of this ligand, namely [M(hfac)2(NIT-2-TrzPm)]·CH2Cl2 (M = Mn (1Mn) and Co (2Co)), [M(hfac)2]2(NIT-2-TrzPm) (M = Mn (3Mn) and Co (4Co)), [Mn(NIT-2-TrzPm)2(MeOH)2](ClO4)2·MeOH (5Mn), and [Co(NIT-2-TrzPm)2(MeOH)2]2(ClO4)4·4MeOH (6Co) were prepared and characterized structurally and magnetically. These complexes can be selectively synthesized by controlling the reaction ratio of M(hfac)2·2H2O to the radical ligand (for 1Mn to 4Co) or using metal perchlorates as the starting materials (for 5Mn and 6Co). Single crystal X-ray crystallographic analyses confirmed that 1Mn and 2Co are isostructural 3d-2p MII-radical complexes, in which the NIT-2-TrzPm radical acts as a terminal bidentate ligand chelating to one 3d ion, while 3Mn and 4Co are isostructural 3d-2p-3d MII-radical-MII complexes with the NIT-2-TrzPm radical acting as a bridging ligand between two 3d ions. For complexes 5Mn and 6Co, two NIT-2-TrzPm ligands from the equatorial positions coordinate with the metal center to form the 2p-3d-2p structures with the axial positions occupied by two methanol molecules. Magnetic analysis on the MnII complexes revealed the existence of a strong antiferromagnetic interaction between the MnII and the NIT radical spin, while weak ferromagnetic coupling for Mn⋯Mn and Rad⋯Rad in the Mn-NIT-Mn and Rad-Mn-Rad spins was confirmed. Interestingly, although the NIT-bridged complexes 3Mn and 4Co possess significantly different magnetic anisotropy, field-induced slow magnetic relaxation can be observed in both complexes, which was assigned to the phonon bottleneck effect for 3Mn and field-induced SMM behavior for 4Co. To the best of our knowledge, 3Mn is the first example of the NIT-bridged binuclear MnII complex undergoing slow magnetic relaxation.

19.
Dalton Trans ; 52(17): 5575-5586, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37013376

RESUMO

Three new cyanide-bridged compounds {[Mn((S,S)-Dpen)]3[Mn((S,S)-Dpen)(H2O)][Mo(CN)7]2·4H2O·4C2H3N}n (1-SS), {[Mn((R,R)-Dpen)]3[Mn((R,R)-Dpen)(H2O)][Mo(CN)7]2·4.5H2O·4C2H3N}n (1-RR), and {[Mn(Chxn)][Mn(Chxn)(H2O)0.8][Mo(CN)7]·H2O·4C2H3N}n (2) (SS/RR-Dpen = (S,S)/(R,R)-1,2-diphenylethylenediamine and Chxn = 1,2-cyclohexanediamine) have been successfully synthesized from the self-assembly reaction of the [MoIII(CN)7]4- unit, the MnII ions, and two chiral bidentate chelating ligands. Single-crystal structure determinations show that compounds 1-SS and 1-RR containing ligands SS/RR-Dpen are enantiomers and crystallize in the chiral space group P21. On the other hand, compound 2 crystallizes in the achiral centrosymmetric space group P1̄ due to the racemization of the SS/RR-Chxn ligands during the growth of the crystals. Despite their different space groups and ligands, all three compounds exhibit similar framework structures consisting of cyano-bridged MnII-MoIII two-dimensional layers separated by the bidentate ligands. The circular dichroism (CD) spectra have further demonstrated the enantiopure character of compounds 1-SS and 1-RR. Magnetic measurements revealed that all three compounds display ferrimagnetic ordering with similar critical temperatures of about 40 K. The chiral enantiomers 1-SS and 1-RR exhibit the magnetic hysteresis loop with a coercive field of about 8000 Oe at 2 K, which is by far the highest for all known MnII-[MoIII(CN)7]4- magnets. Analyses of their structures and magnetic properties indicated that their magnetic properties depend on the anisotropic magnetic interactions between the MnII and MoIII centers, which are closely related to the C-N-M bond angles.

20.
World J Pediatr ; 2023 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-38070096

RESUMO

BACKGROUND: The aim of this study was to characterize the variable phenotypes and outcomes associated with the methylmalonic aciduria and homocystinuria type C protein gene (MMACHC) c.482G > A mutation in 195 Chinese cases with CblC disease. METHODS: We carried out a national, retrospective multicenter study of 195 Chinese patients with CblC disease attributable to the MMACHC c.482G > A variant either in a homozygous or compound heterozygous state. The control group consisted of 200 patients diagnosed with CblC disease who did not possess the c.482G > A mutation. Clinical features, including disease onset, symptoms, biochemical metabolites, gene mutation, and follow-up outcomes were reviewed and analyzed in detail. The median follow-up period spanned 3 years and 8 months, with a range of 1 year and 2 months to 12 years and 10 months. RESULTS: Among 195 patients carrying the c.482G > A variant, 125 (64.1%) cases were diagnosed by newborn screening (NBS), 60 (30.8%) cases were detected due to disease onset, and 10 (5.1%) cases were identified from sibling diagnoses. One hundred and seventeen (93.6%) individuals who were diagnosed by NBS, and nine patients who came from sibling diagnoses remained asymptomatic in this study. From 69 symptomatic patients of the c.482G > A group, more patients presented with later onset, and the top six common clinical symptoms at disease onset were developmental delay (59.4%), lower limb weakness and poor exercise tolerance (50.7%), cognitive decline (37.7%), gait instability and abnormal posture (36.2%), seizures (26.1%), and psychiatric and behavioral disturbances (24.6%). In the 159 symptomatic patients lacking c.482G > A variants, the most frequently observed clinical manifestations at disease onset included developmental delay (81.8%), lethargy and feeding difficulty (62.9%), lower limb weakness and poor exercise tolerance (54.7%), prolonged neonatal jaundice (51.6%), vomiting (47.2%), and seizures (32.7%). Before treatment, the levels of blood propionylcarnitine, propionylcarnitine/acetylcarnitine ratio, and homocysteine in the c.482G > A group were significantly lower (P < 0.05) than those in the non-c.482G > A group, while the concentration of urinary methylmalonic acid was slightly lower (P > 0.05). The degree of decline in the above metabolites after treatment in different groups significantly differed in both plasma total homocysteine values and urinary methylmalonic acid levels (P < 0.05). In patients carrying the c.482G > A variant compared with the non-c.428G > A group, there were markedly lower rates of mortality (0.5% vs. 2.0%) and developmental delay (20.5% vs. 65.5%). When compared with individuals diagnosed due to disease onset, those identified through NBS in either group exhibited a reduced proportion of disease onset (6.7% vs. 100% in the c.482G > A group, 54.4% vs. 100% in the non-c.482G > A group), lower mortality (0.0% vs. 1.7% in the c.482G > A group, 0.0% vs. 3.6% in the non-c.482G > A group), and had a higher percentage of patients exhibiting normal psychomotor and language development (99.3% vs. 33.3% in the c.482G > A group, 58.9% vs. 10.9% in the non-c.482G > A group). CONCLUSIONS: The c.482G > A variant in MMACHC is associated with late-onset and milder phenotypes of CblC disease. Patients with this mutation tend to have a relatively better response to hydroxocobalamin, better metabolic control, and more favorable neurological outcomes. NBS and other appropriate pre-symptomatic treatments seem to be helpful in early diagnosis, resulting in favorable clinical outcomes. Video Abstract (MP4 136794 kb).

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