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1.
Acta Pharmacol Sin ; 45(4): 728-737, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38086898

RESUMO

Stimulation of adult cardiomyocyte proliferation is a promising strategy for treating myocardial infarction (MI). Earlier studies have shown increased CCL2 levels in plasma and cardiac tissue both in MI patients and mouse models. In present study we investigated the role of CCL2 in cardiac regeneration and the underlying mechanisms. MI was induced in adult mice by permanent ligation of the left anterior descending artery, we showed that the serum and cardiac CCL2 levels were significantly increased in MI mice. Intramyocardial injection of recombinant CCL2 (rCCL2, 1 µg) immediately after the surgery significantly promoted cardiomyocyte proliferation, improved survival rate and cardiac function, and diminished scar sizes in post-MI mice. Alongside these beneficial effects, we observed an increased angiogenesis and decreased cardiomyocyte apoptosis in post-MI mice. Conversely, treatment with a selective CCL2 synthesis inhibitor Bindarit (30 µM) suppressed both CCL2 expression and cardiomyocyte proliferation in P1 neonatal rat ventricle myocytes (NRVMs). We demonstrated in NRVMs that the CCL2 stimulated cardiomyocyte proliferation through STAT3 signaling: treatment with rCCL2 (100 ng/mL) significantly increased the phosphorylation levels of STAT3, whereas a STAT3 phosphorylation inhibitor Stattic (30 µM) suppressed rCCL2-induced cardiomyocyte proliferation. In conclusion, this study suggests that CCL2 promotes cardiac regeneration via activation of STAT3 signaling, underscoring its potential as a therapeutic agent for managing MI and associated heart failure.


Assuntos
Insuficiência Cardíaca , Infarto do Miocárdio , Humanos , Camundongos , Animais , Ratos , Quimiocina CCL2/metabolismo , Infarto do Miocárdio/metabolismo , Miócitos Cardíacos , Insuficiência Cardíaca/metabolismo , Regeneração , Camundongos Endogâmicos C57BL , Apoptose , Fator de Transcrição STAT3/metabolismo
2.
Acta Pharmacol Sin ; 44(6): 1149-1160, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36473990

RESUMO

Heart failure with preserved ejection fraction (HFpEF) is highly prevalent, and lacks effective treatment. The aberration of WNT pathway underlies many pathological processes including cardiac fibrosis and hypertrophy, while porcupine is an acyltransferase essential for the secretion of WNT ligands. In this study we investigated the role of WNT signaling pathway in HFpEF as well as whether blocking WNT signaling by a novel porcupine inhibitor CGX1321 alleviated HFpEF. We established two experimental HFpEF mouse models, namely the UNX/DOCA model and high fat diet/L-NAME ("two-hit") model. The UNX/DOCA and "two-hit" mice were treated with CGX1321 (3 mg·kg-1·d-1) for 4 and 10 weeks, respectively. We showed that CGX1321 treatment significantly alleviated cardiac hypertrophy and fibrosis, thereby improving cardiac diastolic function and exercise performance in both models. Furthermore, both canonical and non-canonical WNT signaling pathways were activated, and most WNT proteins, especially WNT3a and WNT5a, were upregulated during the development of HEpEF in mice. CGX1321 treatment inhibited the secretion of WNT ligands and repressed both canonical and non-canonical WNT pathways, evidenced by the reduced phosphorylation of c-Jun and the nuclear translocation of ß-catenin and NFATc3. In an in vitro HFpEF model, MCM and ISO-treated cardiomyocytes, knockdown of porcupine by siRNA leads to a similar inhibitory effect on WNT pathways, cardiomyocyte hypertrophy and cardiac fibroblast activation as CGX1321 did, whereas supplementation of WNT3a and WNT5a reversed the anti-hypertrophy and anti-fibrosis effect of CGX1321. We conclude that WNT signaling activation plays an essential role in the pathogenesis of HFpEF, and porcupine inhibitor CGX1321 exerts a therapeutic effect on HFpEF in mice by attenuating cardiac hypertrophy, alleviating cardiac fibrosis and improving cardiac diastolic function.


Assuntos
Cardiomiopatias , Acetato de Desoxicorticosterona , Insuficiência Cardíaca , Animais , Camundongos , Cardiomegalia/patologia , Cardiomiopatias/patologia , Acetato de Desoxicorticosterona/farmacologia , Acetato de Desoxicorticosterona/uso terapêutico , Fibrose , Insuficiência Cardíaca/metabolismo , Miócitos Cardíacos , Volume Sistólico/fisiologia , Via de Sinalização Wnt
3.
BMC Pregnancy Childbirth ; 21(1): 148, 2021 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-33602166

RESUMO

BACKGROUND: In the entire population, an aberrant right subclavian artery (ARSA) is closely associated with chromosomal abnormalities. ARSA with additional ultrasonic findings would increase risk of chromosomal abnormalities. The risk of fetal chromosomal abnormalities increased exponentially with the maternal age. These risks in the advanced maternal age (AMA) group are uncertain. This study aimed to determine the incidence of ARSA in Chinese AMA and non-AMA women and the frequency of aneuploidy among AMA and non-AMA women with ARSA. METHODS: This retrospective study included 13,690 singleton pregnancies, were divided into AMA and non-AMA groups. Integrated obstetric ultrasonic screening, biochemical screening, noninvasive prenatal screening, and fetal karyotype analysis were analyzed. RESULTS: The overall incidence of ARSA was 0.69%, with no difference between age groups. The incidence of chromosomal abnormalities in the AMA group (37 / 2860) was much higher than that of the non-AMA group. The risk of chromosomal abnormalities significantly increased with both ARSA detected and additional ultrasound findings. With combined ARSA and AMA, the likelihood of the incidence of chromosomal abnormalities increased. Chimerism (45X / 46XX) was found with isolated ARSA in AMA pregnancies. CONCLUSION: There is a high prevalence of chromosomal abnormalities in fetuses of AMA women. ARSA increases the risk of chromosomal abnormalities in both age groups, especially combined with ARSA. When ARSA occurs in AMA women, it confers a high likelihood of chromosomal abnormalities.


Assuntos
Aneuploidia , Anormalidades Cardiovasculares/diagnóstico por imagem , Aberrações Cromossômicas , Artéria Subclávia/anormalidades , Adulto , Anormalidades Cardiovasculares/epidemiologia , Feminino , Humanos , Incidência , Cariotipagem , Idade Materna , Gravidez , Segundo Trimestre da Gravidez , Estudos Retrospectivos , Fatores de Risco , Artéria Subclávia/diagnóstico por imagem , Ultrassonografia Pré-Natal , Adulto Jovem
4.
Med Sci Monit ; 26: e924325, 2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-33046685

RESUMO

BACKGROUND Ultrasound (US) is the preferred imaging method for cryptorchidism, but most guidelines indicate that its value is questionable. The aim of this study was to evaluate the clinical value of ultrasonic mobility and testicular atrophy index (TAI) based on three­dimensional US (3DUS) in preoperative and postoperative assessment of the undescended testis. MATERIAL AND METHODS Data from 158 children with unilateral extraperitoneal cryptorchidism were collected and their diagnoses were surgically confirmed. They were divided into different age groups and into 2 ultrasonic mobility groups: the mobile group (MG) and the restricted group (RG). Differences in sonographic characteristics between different groups were compared. Three-dimensional ultrasound performed with virtual organ computer-aided analysis (VOCAL) was used to determined preoperative and postoperative TAI and the reliability of TAI was analyzed. RESULTS Measurement of testicular volume with the VOCAL method was significantly more reliable than that done with the two-dimensional Lambert method. In all age groups, preoperative testicular volumes were smaller than that in the contralateral scrotal testis and postoperatively, they increased steadily. Both preoperative and postoperative TAI were higher in the RG than in the MG. In the MG, postoperative TAI decreased significantly in all age groups. In the RG, in contrast, effective volume growth was only achieved in patients who had undergone surgery before they reached age 1 year. CONCLUSIONS TAI values determined with 3DUS using the VOCAL technique objectively reflect recovery of testicular volume following surgery for undescended testicle. Ultrasonic mobility evaluation is beneficial for clinical management of the condition.


Assuntos
Criptorquidismo , Ecocardiografia Tridimensional , Cuidados Pós-Operatórios , Cuidados Pré-Operatórios , Testículo , Criança , Criptorquidismo/diagnóstico por imagem , Criptorquidismo/cirurgia , Humanos , Masculino , Tamanho do Órgão , Estudos Retrospectivos , Testículo/diagnóstico por imagem , Testículo/cirurgia
5.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(7): 1849-52, 2014 Jul.
Artigo em Zh | MEDLINE | ID: mdl-25269294

RESUMO

The chemical differences of panax notoginseng before and after processing were analyzed by Fourier transform Infrared spectroscopy (FTIR) combined with two-dimensionalcorrelation spectroscopy (2D-IR). Compared with conventional IR spectra of the samples, the FTIR spectra of panax notoginseng and its processed products were similar in the range of 1 200-400 cm(-1). The difference was that prepared panax notoginseng had strong and characteristic peaks at 2 925, 2 855, 1 746, 1 460, 1 376 and 1 158 cm(-1), which all arose from the characteristic vibration of peanut oil. This was because there was some peanut oil left in the panax notoginseng, when panax notoginseng after processing. Obvious differences were observed between 2D-IR spectra of them, in the range of 1 400-1 700 cm(-1), there was only one auto peaks at 1 650 cm(-1) in the spectra of panax notoginseng, but there were auto peaks at 1 469 and 1 640 cm(-1) in the spectra of prepared panax notoginseng. In the range of 1 400-1 700 cm(-1), the 2D-IR spectra of panax notoginseng and its processed product present characterstic peaks at 1 139 (1 137), 1 194 (1 196), 1 121 (1 221)cm(-1) respectively, but the relative intensities of auto peaks were changed. For example, auto peak around 1 139 cm(-1) was enhanced, but auto peak around 1 194 cm(-1) was weakened. The results of 2D-IR correlation spectroscopy indicated the decomposition of flavonoids, saccharides and saponins. This method can track dynamically the processing procedure of panax notoginseng and reveal the main tansformations, so it can explain the pharmacology of panax notoginseng and its processed product by FTIR and 2D-IR.


Assuntos
Panax notoginseng/química , Espectroscopia de Infravermelho com Transformada de Fourier , Carboidratos/análise , Flavonoides/análise , Saponinas/análise
6.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(5): 1206-10, 2013 May.
Artigo em Zh | MEDLINE | ID: mdl-23905320

RESUMO

From the determination of the infrared spectra of four substances (original ganoderma lucidum and ganoderma lucidum water extract, 95% ethanol extract and petroleum ether extract), it was found that the infrared spectrum can carry systematic chemical information and basically reflects the distribution of each component of the analyte. Ganoderma lucidum and its extracts can be distinguished according to the absorption peak area ratio of 3 416-3 279, 1 541 and 723 cm(-1) to 2 935-2 852 cm(-1). A method of calculating the information entropy of the sample set with Euclidean distance was proposed, the relationship between the information entropy and the amount of chemical information carried by the sample set was discussed, and the authors come to a conclusion that sample set of original ganoderma lucidum carry the most abundant chemical information. The infrared spectrum set of original ganoderma lucidum has better clustering effect on ganoderma atrum, Cyan ganoderma, ganoderma multiplicatum and ganoderma lucidum when making hierarchical cluster analysis of 4 sample set. The results show that infrared spectrum carries the chemical information of the material structure and closely relates to the chemical composition of the system. The higher the value of information entropy, the much richer the chemical information and the more the benefit for pattern recognition. This study has a guidance function to the construction of the sample set in pattern recognition.


Assuntos
Extratos Vegetais/química , Reishi/química , Espectrofotometria Infravermelho/métodos , Análise Espectral/métodos
7.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(8): 2105-9, 2012 Aug.
Artigo em Zh | MEDLINE | ID: mdl-23156761

RESUMO

The objective of the present study is to analyze different products of Guilin watermelon frost by Fourier transform infrared spectroscopy (FTIR), second derivative infrared spectroscopy and two-dimensional correlation spectroscopy (2D-IR) under thermal perturbation. The structural information of the samples indicates that samples from the same factory but of different brands had some dissimilarities in the IR spectra, and the type and content of accessories of them were different compared with conventional IR spectra of samples, peaks at 638 and 616 cm(-1) all arise from anhydrous sodium sulfate in watermelon frost spray and watermelon frost capsule; the characteristic absorption peaks of the sucrose, dextrin or other accessories can be seen clearly in the spectra of watermelon frost throat-clearing buccal tablets, watermelon frost throat tablets and watermelon frost lozenge. And the IR spectra of watermelon frost lozenge is very similar to the IR spectra of sucrose, so it can be easily proved that the content of sucrose in watermelon frost lozenge is high. In the 2D-IR correlation spectra, the samples presented the differences in the position, number and relative intensity of autopeaks and correlation peak clusters. Consequently, the macroscopical fingerprint characters of FTIR, second derivative infrared spectra and 2D-IR spectra can not only provide the information about main chemical constituents in medical materials, but also analyze and identify the type and content of accessories in Guilin watermelon frost. In conclusion, the multi-steps IR macro-fingerprint method is rapid, effective, visual and accurate for pharmaceutical research.


Assuntos
Citrullus , Medicamentos de Ervas Chinesas/análise , Espectrofotometria Infravermelho , Espectroscopia de Infravermelho com Transformada de Fourier
8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(8): 2131-4, 2012 Aug.
Artigo em Zh | MEDLINE | ID: mdl-23156766

RESUMO

In the present paper, the similar spectra of 18 samples, which include Astragalus, red-blue Astragalus and Codonopsis, were obtained in the range of 1600-700 cm(-1). The result showed that all kinds of herbs have their own characteristic similar spectra, and 18 samples can be identified according to the characteristic similar spectra. Furthermore, three correlation coefficients of 93 ganoderma samples were calculated which is in the range of 1560-1502, 1460-1421 and 1319-1260 cm(-1) according to the information of similar spectrum of infrared spectrum of ganoderma. Without priori knowledge of the classification of these samples, the K-means cluster analysis can successfully divide them into four classes, i.e., Ganoderma lucidum and Ganoderma sinensis, Ganoderma atrum, Ganoderma aoshiba, Ganoderma multiplicatum. This result is consistent with the result of morphological classification.


Assuntos
Astrágalo/química , Codonopsis/química , Ganoderma/química , Ganoderma/classificação , Espectrofotometria Infravermelho
9.
Prenat Diagn ; 30(12-13): 1192-7, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21064194

RESUMO

OBJECTIVE: To determine the effects of increased ultrasound probe pressure and maternal Valsalva maneuver (VM) on the middle cerebral artery (MCA) Doppler ultrasonography in fetuses. METHODS: A total of 120 healthy pregnant women in second and third trimesters were enrolled in the study. MCA blood flow was measured by pulsed Doppler sonography in 60 fetuses (24 and 40 weeks' gestation) before and after the application of increased ultrasound probe pressure. In the other 60 fetuses (32 and 36 weeks' gestation), sonography was performed before and after maternal VM. Statistical analysis was performed by paired t-test. RESULTS: The pressure induced by the ultrasound probe induced a significant increase in the pulsatility index (PI), resistance index (RI), and peak systolic velocity (PSV); however, a significant decrease was found in the end-diastolic velocity (EDV) (p < 0.05). No statistically significant difference was found in the mean flow velocity (MFV). Moreover, maternal VM did not have any effect on the PI, RI, EDV, or MFV. CONCLUSION: Fetal MCA Doppler assessment is affected by increased probe pressure but not by maternal VM. Thus, the application of the MCA Doppler sonography should be undertaken in the head of fetuses without any probe pressure and without maternal VM.


Assuntos
Feto/irrigação sanguínea , Artéria Cerebral Média/diagnóstico por imagem , Mães , Pressão/efeitos adversos , Ultrassonografia Doppler de Pulso/efeitos adversos , Ultrassonografia Pré-Natal/efeitos adversos , Manobra de Valsalva/fisiologia , Velocidade do Fluxo Sanguíneo/fisiologia , Pressão Sanguínea/fisiologia , Feminino , Humanos , Recém-Nascido , Gravidez , Segundo Trimestre da Gravidez/fisiologia , Terceiro Trimestre da Gravidez/fisiologia , Ultrassonografia Doppler de Pulso/métodos , Ultrassonografia Pré-Natal/instrumentação , Ultrassonografia Pré-Natal/métodos
10.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(1): 78-82, 2010 Jan.
Artigo em Zh | MEDLINE | ID: mdl-20302086

RESUMO

Ganoderma lucidum, ganoderma atrum, ganderma tsugae Murr. and ganoderma lipsiense can be discriminated and identified by using multi-steps infrared macro-fingerprint method. The 1D-1R spectra, based on the peaks intensity at 1153 and 1078 cm(-1), which are the fingerprint characteristic peaks of glucoside compounds, show that the content of glucoside compounds of them was in the order of: ganoderma lucidum>ganoderma atrum>ganderma tsugae Murr. >ganoderma lipsiense. Generally, the second derivative IR spectra can clearly enhance the spectra resolution. In the range of 1600-1720 cm(-1), the position and sharpness of characteristics peaks were very different, and it's proved that amino acid peptide compounds of them were different. In the 2D-IR spectra, four of them have the same autopeak at 1100 cm(-1), which is the autopeaks of glucoside, but the number of autopeaks of ganoderma lucidum was 4 and its strongest autopeak was 1040 cm(-1), while 5 autopeaks, 4 autopeaks and 5 autopeaks were for ganoderma atrum, ganderma tsugae Murr. and ganoderma lipsiense respectively, and their strongest autopeaks were 1040, 1139, 1140 and 1134 cm(-1) respectively. The multi-steps infrared maro-fingerprint identification testified that the contents of glucoside compounds and amino acid peptide compounds in these four kinds of ganoderma are different. It's proved that multi-steps infrared maro-fingerprint method can be used to analyze and distinguish ganoderma lucidum, ganoderma atrum, ganderma tsugae Murr. and ganoderma lipsiense.


Assuntos
Ganoderma/classificação , Espectrofotometria Infravermelho , Aminoácidos/química , Ganoderma/química , Glucosídeos/química , Especificidade da Espécie
11.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(9): 2396-400, 2009 Sep.
Artigo em Zh | MEDLINE | ID: mdl-19950637

RESUMO

Standard Huangqi (Astragalus membranaceus (Fisch) Bge. Var. monghlicus (Bge.) Hsiao) and its counterfeit Ciguogancao (Glychrrhiza pallidiflora Maxim.) can be discriminated and identified by using multi-steps infrared maro--fingerprint method. In the 1D-IR spectra, the peak intensity at 1 737 cm(-1) for Ciguogancao, which is the stretching vibration peak of C==O, is much stronger than that of Huangqi. It's proved that the organic ester compounds in Ciguogancao are much more than Huangqi. In the secondary derivative spectra, it's easy to find the fingerprint characteristic peaks of CaC2O4 in the infrared spectra of Ciguogancao, but not in that of Huangqi. Besides, both secondary derivative spectra also have main characteristic peaks, which are the skeletal stretching of aromatic, round 1463, 1511 and 1596 cm(-1), but Ciguogancao aslo has one shoulder peak at 1 453 cm(-1). In the 2D-IR spectra, both have three auto-peaks at 1070, 1095 and 1140 cm(-1), which are the autopeaks of glucoside, but the strongest auto-peak of Huangqi is at 1140 cm(-1) and that of Ciguogancao's is at 1 090 cm(-1). The spectra testified that the organic ester compounds, aromatic compounds and glucoside compounds in Huangqi and its counterfeit Ciguogancao were different. The method not only can identify standard Huangqi and its counterfeit Ciguogancao rapidly, but also provides useful information about the differences in organic ester compounds, aromatic compounds and glucoside between Huangqi and its counterfeit Ciguogancao. It's proved that multi-steps infrared maro-fingerprint method can be used to analyze and distinguish Huangqi and its counterfeit Ciguogancao.


Assuntos
Medicamentos Falsificados/análise , Medicamentos de Ervas Chinesas/análise , Astragalus propinquus , Espectrofotometria Infravermelho
12.
J Med Ultrason (2001) ; 46(1): 113-122, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30291575

RESUMO

PURPOSE: To obtain three-dimensional ultrasonic (3D US) structural details and biometrics of the fetal cerebellar vermis and evaluate the value of developmental and malformation identification. METHODS: The 3D US minute structure of the fetal cerebellar vermis in mid-sagittal view was detected in normal fetuses (n = 438; 16-41 weeks). Biometric sizes were measured to establish the stage-specific norms and reproducibility analysis. Additionally, 28 fetuses with suspected abnormal posterior fossa contents were assessed to analyze the clinical value. RESULTS: The minute structure of normal fetuses, including cerebellar vermis contours and the fastigial recess of the fourth ventricle, were visible around Week 19. The main lobules and fissures were apparent around Week 22, and all nine lobules, fissures, and the fourth ventricle were clearly displayed by Week 28. Cerebellar vermis biometric sizes (anterior-posterior length, cranio-caudal length, circumference, and surface area (SA)) grew in a linear fashion with high reliability, especially SA measurements (for intraclass, ICC 0.989, 95% CI (0.980-0.994); for interclass, ICC 0.992, 95% CI (0.984-0.996)). On the middle sagittal section of 3D US, the SA reduced at least 50% in the Dandy-Walker group with no recognizable cerebellar vermis structures showing. The SA in vermian hypoplasia malformation reduced during [Formula: see text] to 50% with the primary/secondary fissures absent or partly absent and arborization of the lobules reduced. That would be an important diagnosis and antidiastole clue. Combined with minute structural observation, sonographic diagnoses were accurate in 88% of cases. CONCLUSION: Minute structures obtained by 3D US were clinically useful in the evaluation of cerebellar vermis development and cerebellar vermis malformations.


Assuntos
Vermis Cerebelar/diagnóstico por imagem , Vermis Cerebelar/embriologia , Desenvolvimento Fetal , Imageamento Tridimensional , Ultrassonografia Pré-Natal/métodos , Biometria , Vermis Cerebelar/anormalidades , Estudos Transversais , Feminino , Idade Gestacional , Humanos , Gravidez , Valores de Referência , Reprodutibilidade dos Testes
13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 27(11): 2239-42, 2007 Nov.
Artigo em Zh | MEDLINE | ID: mdl-18260403

RESUMO

The infrared spectrum of Chinese herbs possesses the character similar to fingerprint. The purpose to identify Chinese herbs can be achieved by way of comparing these spectra. The software of comparing correlation coefficient array of FTIR spectra was designed in Visual Basic 6.0. It established an infrared spectrum database including more than 300 kinds of Chinese herbs. The FTIR spectra of unknown herb can be compared with those of Chinese herbs in the database, and this method can identify the suitable herbs according to the similar herbs in the database. The study shows that within the spectral database of herbs, the factors of spectral interference, such as H2O, CO2, etc., can be avoided through assigning threshold values of correlation coefficients and comparing spectra with characteristic peak bands, and the comparison result is credible and correct. This method was expected to be a common method in identifying Chinese herbs.


Assuntos
Medicamentos de Ervas Chinesas/análise , Plantas Medicinais/química , Análise Espectral/métodos , Controle de Qualidade
14.
Guang Pu Xue Yu Guang Pu Fen Xi ; 23(1): 54-7, 2003 Feb.
Artigo em Zh | MEDLINE | ID: mdl-12939967

RESUMO

Four tridentate acylhydrazone schiff base ligands H2L [H2L1:C6H5C(O)NHN = CHC6H4OH-2, H2L2:C6H5C(O)NHN = CHC6H3(OH)(2)-2,4, H2L3:NC5H4C(O)NHN = CHC6H4OH-2, H2L4:NC5H4C(O)NHN = CHC6H3(OH)(2)-2,4] were synthesized and use to form four novel di-n-Butytin complexes of the type (n-Bu)2SnL with di-n-Butytin oxide [(n-Bu)2SnO]. All these ligands and complexes were characterized by elemental analysis and infrared spectroscopy. Their principal infrared spectral absorption peaks were assigned and discussed for the region of 4,000-400 cm-1. A comparison of the infrared spectra of the ligands with those of the corresponding complexes reveals that the disappearance of the bands assigned to carbonyl unambiguously confirms that the ligands coordinate with tin in the enol form. The coordination manner for tridentate acylhydrazone schiff base ligands with tin atom in the complexes was determined. The results indicated that the Sn atom in these complexes is five-coordinated.


Assuntos
Hidrazonas/síntese química , Compostos Organometálicos/síntese química , Compostos Orgânicos de Estanho/síntese química , Bases de Schiff/síntese química , Hidrazonas/química , Ligantes , Estrutura Molecular , Compostos Organometálicos/química , Compostos Orgânicos de Estanho/química , Bases de Schiff/química , Espectrofotometria Infravermelho , Estanho/química
15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 24(8): 991-4, 2004 Aug.
Artigo em Zh | MEDLINE | ID: mdl-15766128

RESUMO

In NH4Cl-NH3 H2O buffer solution of pH 10.4, diazo salt of p-sulfodiazoben-zene chloride reacts with rutin, morin, genistin, quercetin, hesperidin, baicalin and daidzin to form color azo-compounds. These azo-compounds have an absorption maximum at 430 nm except for baicalin azo-compound, which has an absorption maximum at 380 nm. The sensitivity of azoic color reaction is reductive in the order of above flavonoids and the molar absorptivity is maximum for rutin and is minimal for daidzin among these azo-compounds, i. e. 3.28 x 10(4) and 8.3 x 10(2) L x mol(-1) x cm(-1) respectively. The proposed spectrophotometry has been applied to th determination of flavonoids in sophora seed and soybean cake. The RSDs of the method were found to be in the range of 0.75-4.48%, and the recoveries were in the range of 99.3%-105.0%.


Assuntos
Flavonoides/química , Espectrofotometria/métodos , Compostos Azo/química , Técnicas de Química Analítica , Cor , Quercetina/química , Rutina/química
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