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1.
BMC Pregnancy Childbirth ; 24(1): 92, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38291360

RESUMO

BACKGROUND: The appropriate use of obstetric blood transfusion is crucial for patients with placenta previa and prenatal anemia. This retrospective study aims to explore the correlation between prenatal anemia and blood transfusion-related parameters in this population. METHODS: We retrieved the medical records of consecutive participants who were diagnosed with placenta previa and underwent cesarean section in our hospital. We compared the baseline demographics and clinical characteristics of patients with and without anemia. The correlation between prenatal anemia and obstetric blood transfusion-related parameters was evaluated using multivariate regression analysis. RESULTS: A total of 749 patients were enrolled, with a mean prenatal hemoglobin level of 10.87 ± 1.37 g/dL. Among them, 54.87% (391/749) were diagnosed with anemia. The rate of obstetric blood transfusion was significantly higher in the anemia group (79.54%) compared to the normal group (44.41%). The median allogeneic red blood cell transfusion volume in the anemia group was 4.00 U (IQR 2.00-6.00), while in the normal group, it was 0.00 U (IQR 0.00-4.00). The prenatal hemoglobin levels had a non-linear relationship with intraoperative allogeneic blood transfusion rate, massive blood transfusion rate, red blood cell transfusion units, and fresh plasma transfusion volume in patients with placenta previa, with a threshold of 12 g/dL. CONCLUSIONS: Our findings suggest that prenatal anemia is associated with a higher rate of blood transfusion-related parameters in women with placenta previa when the hemoglobin level is < 12 g/dL. These results highlight the importance of promoting prenatal care in placenta previa patients with a high requirement for blood transfusion.


Assuntos
Anemia , Transfusão de Sangue , Placenta Acreta , Placenta Prévia , Feminino , Humanos , Gravidez , Anemia/etiologia , Anemia/terapia , Transfusão de Componentes Sanguíneos , Cesárea/efeitos adversos , Cesárea/métodos , Hemoglobinas , Placenta Acreta/cirurgia , Placenta Prévia/epidemiologia , Placenta Prévia/cirurgia , Plasma , Estudos Retrospectivos , Complicações Hematológicas na Gravidez/terapia
2.
Med Sci Monit ; 29: e940443, 2023 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-37559346

RESUMO

BACKGROUND Placenta accreta spectrum (PAS) disorders involve abnormal adhesion or invasion of chorionic villi through the myometrium and uterine serosa. Maternal anemia during pregnancy is common and may contribute to complications during delivery, particularly with abnormal placentation. This study examines the association between preoperative maternal hemoglobin levels and the risk of intraoperative massive hemorrhage in pregnant women with PAS disorders. MATERIAL AND METHODS A retrospective study included 538 consecutive participants (mean age=31.12±4.68 years) who underwent cesarean sections and met the diagnostic criteria for PAS disorders. Logistic regression analysis was performed to investigate the relationship between maternal preoperative hemoglobin levels and the risk of massive intraoperative hemorrhage (blood loss ≥1500 mL). RESULTS The incidence of intraoperative massive hemorrhage among patients with PAS disorders was 38.66%. The mean preoperative maternal hemoglobin level was 10.99±1.39 g/dL, and overall anemia incidence (<11 g/dL) was 48.88% in our study. After adjusting for potential confounders, a non-linear relationship was observed between preoperative maternal hemoglobin levels and the risk of intraoperative massive hemorrhage. When the preoperative hemoglobin level of pregnant women was below 11.5 g/dL (OR=0.52, 95% CI 0.39-0.70), the lower hemoglobin level significantly increased the risk of intraoperative hemorrhage. CONCLUSIONS Maternal preoperative hemoglobin levels were inversely associated with the risk of massive intraoperative hemorrhage in PAS disorders. A non-linear relationship was identified, with a turning point at 11.5 g/dL. These findings emphasize the importance of monitoring and managing maternal hemoglobin levels to mitigate the risk of intraoperative hemorrhage in pregnant women with PAS disorders.


Assuntos
Placenta Acreta , Placenta , Gravidez , Feminino , Humanos , Adulto , Estudos Retrospectivos , Estudos Transversais , Placenta Acreta/cirurgia , Placenta Acreta/epidemiologia , Perda Sanguínea Cirúrgica , Hemoglobinas
3.
BMC Pregnancy Childbirth ; 23(1): 406, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37264325

RESUMO

BACKGROUND: To evaluate the effect of placental location on the severity of placenta accreta spectrum (PAS). METHODS: We analyzed 390 patients with placenta previa combined with placenta accreta spectrum who underwent cesarean section between January 1, 2014 and December 30, 2020 in the electronic case database of the Second Hospital of Hebei Medical University. According to the position of the placenta, 390 placentas were divided into the posterior group (n = 89), the anterior group (n = 60) and the non-central group (n = 241). RESULTS: The history of cesarean delivery rates in the anterior group (91.67%) and the non-central group (85.71%) were statistically different from the posterior group (63.74%)(P < 0.001). Univariate logistic regression results showed that employment, urban living, gestational age, complete placenta previa, fetal presentation shoulder, gravidity, cesarean section and vaginal delivery were all predictors for the severity of placenta accreta (P < 0.05). The anterior group (P = 0.001, OR = 4.13, 95%CI: 1.84-9.24) and the non-central group (P = 0.001, OR = 2.90, 95%CI: 1.55-5.45) had a higher incidence of invasive accreta placentation than the posterior group, and were independent risk factors for invasive accreta placentation. CONCLUSION: Compared with posterior placenta, anterior and non-central placenta are independent risk factors for invasive PAS in patients with placenta previa, during which we should be more cautious in treatment.


Assuntos
Placenta Acreta , Placenta Prévia , Gravidez , Humanos , Feminino , Placenta Acreta/epidemiologia , Cesárea/efeitos adversos , Placenta Prévia/epidemiologia , Placenta/diagnóstico por imagem , Estudos Retrospectivos
4.
Microb Pathog ; 143: 104139, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32173492

RESUMO

Ulcerative colitis (UC) is a long-lasting inflammation disease which finally results in ulcer of the colon and rectum. The long non-coding RNA (lncRNA) TUG1 has been described to target miR-142 and regulate its expression. In current study, we evaluated the effects of long non-coding RNA TUG1 on cell injury and inflammatory cytokine production using a TNFα-treated HT-29 cells model. We monitored the level of TUG1 in colonic mucosa tissue of UC patients and in TNF-α-treated HT-29 cells. We investigated the effects of TUG1 on miR-142-5p and SOCS1expression, cell viability, lactate dehydrogenase (LDH) release, production of nitrite and PGE2 after TNF-α treatment in HT-29 cells. We also investigated the effects of TUG1 on TNF-α-induced IL-6, IL-8 and IL-1ß expression in HT-29 cells. We detected down-regulated TUG1 level in colonic mucosa tissue of UC patients and in TNF-α-treated HT-29 cells. Overexpression of TUG1 enhanced cell viability, decreased LDH release, decreased nitrite and PGE2 production after TNF-α treatment in HT-29 cells. TUG1 prevented IL-1ß, IL-6 and IL-8 production in TNF-α-treated cells. TUG1 targeted miR-142-5p and inhibited its expression while enhanced SOCS1 expression. Overexpression of miR-142-5p abolished TUG1-mediated inhibition of TNF-induced inflammatory cytokines production. TUG1 negatively regulated inflammation in ulcerative colitis through miR-142-5p/SOCS1 axis.


Assuntos
Colite Ulcerativa/metabolismo , MicroRNAs/metabolismo , RNA Longo não Codificante/metabolismo , Proteína 1 Supressora da Sinalização de Citocina/metabolismo , Western Blotting , Ensaio de Imunoadsorção Enzimática , Células HT29 , Humanos , Inflamação/metabolismo , Interleucinas/metabolismo , Mucosa Intestinal/metabolismo , Reação em Cadeia da Polimerase em Tempo Real
5.
Materials (Basel) ; 12(3)2019 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-30691209

RESUMO

Their controlled release property is the most important feature of functional microcapsules and carriers. In this work, melamine resin shell fragrance microcapsules were fabricated in a non-ionic system, and their chemical structure, particle size, and morphology were analyzed. The sustained release property of the prepared microcapsules over 2400 h was studied with a weighing calculation method, and based on the fitting results, the release rate trend was consistent with the Peppas model (y = 100 - 2.30t0.3213). Furthermore, the sustained and broken release behavior of the microcapsules in impregnated fabric samples were investigated for the first time by our proposed Solid Phase Microextraction-Gas Chromatography-Mass Spectrometer (SPME-GC-MS) method. The qualitative and quantitative analysis results showed that the middle and base note compositions were outstanding in the sustained release state, and the top note showed more advantages in the broken release state. In addition, it was found that the characteristic peak species and intensities of the sample finished with the microcapsules were more similar to pure essence oil than the sample finished by traditional methods, suggesting that the prepared microcapsules showed an excellent odor recovery and strength.

6.
RSC Adv ; 9(43): 25225-25231, 2019 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-35528675

RESUMO

The relation between the particle size and release characteristics of aromatic microcapsules with a melamine resin shell in functional textile applications have been investigated. Firstly, the microcapsules are characterized based on their Fourier transform infrared spectra, encapsulation efficiencies, particle size distributions, optical images, and scanning electron microscopy images. The impregnation performances of the microcapsules have been initially evaluated using image analysis. Subsequently, the impregnation efficiency and broken release characteristics are semi-quantitatively analyzed using solid-phase microextraction-gas chromatography-mass spectrometry. The analysis results show that the highest impregnation efficiency and broken release intensity could be observed when the microcapsule size was similar to the fiber diameter (25-30 µm). Eventually, the sustained release of the microcapsules over a period of 2400 h was evaluated using the weighing calculation method, and the trends were studied using the Peppas model. It was found that the microcapsule release rate slowly and continuously decreased with time, and the release rates significantly increased with the decrease in microcapsule particle size. Thus, it could be concluded that the large microcapsules exhibited better leak tightness than the small microcapsules, whereas the small microcapsules exhibited faster sustained release rates.

7.
J Pharm Pharmacol ; 70(10): 1369-1377, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29943422

RESUMO

OBJECTIVES: To explore the potential therapeutic effect of Tanshinone IIA against ovarian cancer in vitro and elucidate the underlying molecular mechanism. METHODS: The cell survival upon Tanshinone IIA treatment was determined by the clonogenic assay. Cell apoptosis was analysed by Annexin V/propidium iodide double staining. The cleaved caspase-3/poly ADP-ribose polymerase and apoptosis-related factors were quantified by Western blotting. The relative expression of microRNAs (miRs) was determined by real-time polymerase chain reaction. KEY FINDINGS: Tanshinone IIA treatment induced significant apoptosis in TOV-21G cells. Tanshinone suppressed survivin expression while not affected Bax, Bcl-2 and Bcl-xL. We further predicted and experimentally confirmed overexpression of miR-205 in TOV-21G, which ectopic significantly inhibited survivin and promoted cell apoptosis. miR-205-specific antagonist completely abrogated the cell suppressive effect of Tanshinone IIA. CONCLUSIONS: Our data suggested that Tanshinone IIA induced cell apoptosis in ovarian carcinoma TOV-21G cells via direct upregulation of miR-205. Our study highlighted the potential therapeutic application of Tanshinone IIA against ovarian malignancy.


Assuntos
Abietanos/farmacologia , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , MicroRNAs/biossíntese , MicroRNAs/farmacologia , Survivina/biossíntese
8.
Spectrochim Acta A Mol Biomol Spectrosc ; 191: 180-188, 2018 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-29032342

RESUMO

As its significant role, the selective recognition of G-quadruplex with specific structures and functions is important in biological and medicinal chemistry. Carbazole derivatives have been reported as a kind of fluorescent probe with many excellent optical properties. In the present study, the fluorescence of the dye (carbazole TO) increased almost 70 fold in the presence of bcl-2 2345 G4 compared to that alone in aqueous buffer condition with almost no fluorescence and 10-30 fold than those in the presence of other DNAs. The binding study results by activity inhibition of G4/Hemin peroxidase experiment, NMR titration and molecular docking simulation showed the high affinity and selectivity to bcl-2 2345 G4 arises from its end-stacking interaction with G-quartet. It is said that a facile approach with excellent sensitive, good selectivity and quick response for bcl-2 2345 G-quadruplex was developed and may be used for antitumor recognition or antitumor agents.


Assuntos
Carbazóis/química , DNA/química , Corantes Fluorescentes/química , Quadruplex G , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Sequência de Bases , Dicroísmo Circular , Humanos , Conformação Molecular , Simulação de Acoplamento Molecular , Espectroscopia de Prótons por Ressonância Magnética , Teoria Quântica , Espectrometria de Fluorescência , Fatores de Tempo
9.
Materials (Basel) ; 10(7)2017 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-28773166

RESUMO

In this study, two novel fluorescent probes, probe A and probe B were designed, synthesized and characterized, based on Microthrix parvicella (M. parvicella) preferring to utilize long-chain fatty acid (LCFA), for the labeling of M. parvicella in activated sludge. The molecular structure of probe A and probe B include long-chain alkane and LCFA, respectively. The results indicated that probe A and probe B had a large stokes shift of 118 nm and 120 nm and high quantum yield of 0.1043 and 0.1058, respectively, which were significantly helpful for the fluorescent labeling. As probe A was more stable than probe B in activated sludge, and the fluorescence intensity keep stable during 24 h, probe A was more suitable for labeling M. parvicella in situ. In addition, through the Image Pro Plus 6 (IPP 6) analysis, a quantitative relationship was established between sludge volume index (SVI) and integral optical density (IOD) of the labeled M. parvicella in activated sludge samples. The relationship between IOD and SVI conforms to Logistic curve (R² = 0.94).

10.
Mater Sci Eng C Mater Biol Appl ; 77: 1151-1159, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28531991

RESUMO

IA multifunctional drug loading system with pH-sensitive, fluorescent and targeting property was fabricated. Firstly, the amphipathic N-octyl-N'-(2-carboxyl-cyclohexamethenyl) chitosan (OCCC) was prepared by grafting hydrophobic octyl group and hydrophilic hexahydrophthalic anhydride onto chitosan, then it was modified with folic acid (FA) and thiazole orange (TO) using polyethylene glycol (PEG) as the link to fabricate a multifunctional drug loading system TO-PEG-OCCC-PEG-FA. Its chemical structure was determined by Fourier transform infrared spectroscopy (FT-IR), elemental analysis, differential scanning calorimetry (DSC) analysis, UV-vis and fluorescence spectrometer, and the results showed that the substitution degree of hydrophobic/hydrophilic group onto chitosan were 41.4% and 59.1% respectively. The FA and TO were successfully grafted onto chitosan using PEG as link, and their grafting degree were 5.1% and 0.216% respectively. The fabricated multifunctional chitosan micelle with a concentration of 10mg/mL showed a 42.76% encapsulation efficiency on 5-fluorouracil, and it was stable under physiological pH (pH=7.4), but showed an excellent pH-sensitive drug release property under acid environment (pH=4.0). Additionally, the drug release amount could reach up to 95% during 4h.


Assuntos
Polímeros/química , Quitosana , Portadores de Fármacos , Concentração de Íons de Hidrogênio , Polietilenoglicóis , Espectroscopia de Infravermelho com Transformada de Fourier
11.
J Fluoresc ; 26(4): 1511-20, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27307022

RESUMO

A novel fluorescent dye, 1-(2-hydroxyethyl)-4-((E)-2-(3-benzothiazol-2yl-9-ethyl-carbazole-3yl)vinyl) pyridinium bromide, was synthesized for determination of protein and its structure was characterized by (1)H NMR. Photophysics of the new probe in different solvents has been delineated in this paper, the new fluorescent molecular dye exhibited a large stokes-shifted and fluorescence quantum yields in organic solvent. The photostability and thermostability of the new dye were also studied and the results suggested the stable was excellent. The interactions of the dye with bovine serum albumin (BSA) , Human serumal bumin (HSA) and calf thymus deoxyribonucleic acid (ctDNA) were studied by fluorescence and absorption spectroscopy. The binding constant for BSA, HSA and DNA were calculated to be 8.91 × 10(7), 1.86 × 10(6) and 2.9 × 10(4), respectively. The experimental results indicated a potential value of the new dye for biomarker.


Assuntos
Benzotiazóis/química , Benzotiazóis/síntese química , Compostos de Piridínio/química , Compostos de Piridínio/síntese química , Soroalbumina Bovina/análise , Soroalbumina Bovina/química , Albumina Sérica Humana/análise , Albumina Sérica Humana/química , Animais , Bovinos , Técnicas de Química Sintética , DNA/análise , DNA/química , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/química , Humanos , Temperatura
12.
Appl Microbiol Biotechnol ; 100(6): 2883-94, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26603763

RESUMO

Although the fluorescent in situ hybridization (FISH) has been widely used to identify the Microthrix parvicella (M. parvicella), there are a few disadvantages and difficulties, such as complicated process, time consuming, etc. In this work, a series of fluorescent probes, which were modified by long-chain alkane with hydrophobic property and based on the property of M. parvicella utilizing long-chain fatty acids (LCFA), for the labeling of M. parvicella in bulking sludge were designed, synthesized, and characterized. The probes were characterized by ultraviolet-visible (UV-Vis) absorption spectra, fluorescence spectra, (1)H NMR spectra, and mass spectra, and the photostability and hydrophobic property of probes were investigated. All the results showed that the probes were quite stable and suitable for the fluorescent labeling. The probes had a large stoke shift of 98-137 nm, which was benefit for the fluorescent labeling. In the fluorescent labeling of M. parvicella by the synthesized probes, the probes had excellent labeling effects. By comparison of the images and the Image Pro Plus 6.0 analysis, the optimal concentration of the probes in the activated sludge sample for labeling was 0.010 mmol/L and the probe 3d had the best labeling. In addition, the effect of the duration time of probes was also investigated, and the results showed that the fluorescent intensity of probes hardly changed in a long period of time and it was suitable for labeling.


Assuntos
Actinobacteria/metabolismo , Alcanos/síntese química , Alcanos/metabolismo , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/metabolismo , Coloração e Rotulagem/métodos , Alcanos/química , Ácidos Graxos/química , Ácidos Graxos/metabolismo , Corantes Fluorescentes/química , Análise Espectral
13.
Spectrochim Acta A Mol Biomol Spectrosc ; 152: 343-51, 2016 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-26232578

RESUMO

The LCC-CdTe quantum dots (QDs) hybrid was fabricated by mixing the N-lauryl-N, O-carboxymethyl chitosan (LCC) micelle with water-soluble CdTe QDs in an aqueous solution via hydrophobic forces and the electronic attraction. The structures of LCC and LCC-CdTe QDs hybrid were determined by differential scanning calorimetry (DSC), Fourier transform infrared (FT-IR) spectroscopy and transmission electron microscopy (TEM). The results showed that the lauryl and carboxymethyl were successfully grafted to chitosan oligosaccharide (CSO), and a number of CdTe QDs were encapsulated by LCC micelle to form a core/shell structure. The tested results of the fluorescent characteristics of LCC, CdTe QDs and LCC-CdTe QDs hybrid showed that there were some obvious fluorescent interactions between LCC and CdTe QDs. Meanwhile, with the change in LCC space structure, the fluorescent interactions between LCC and QDs showed different fluorescent characteristics. The QDs fluorescent (FL) intensity increased first and then decreased to almost quenching, while LCC FL intensity decreased continually.


Assuntos
Compostos de Cádmio/química , Quitosana/análogos & derivados , Corantes Fluorescentes/química , Pontos Quânticos/química , Telúrio/química , Quitosana/química , Fluorescência , Pontos Quânticos/ultraestrutura , Solubilidade , Água/química
14.
Langmuir ; 29(17): 5132-7, 2013 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-23582023

RESUMO

The interaction of dyes with a sulfonated Gemini surfactant was investigated in aqueous solution using Förster resonance energy transfer with acridine orange (AO) as a donor and rhodamine B (RhB) as an acceptor. Surface tension results showed that AO and RhB have different effects on the self-assembly of the Gemini surfactant, with AO giving a higher critical micelle concentration (cmc) and lower surface tension, while the opposite was observed for RhB. Energy transfer from AO to RhB was observed in the presence of the surfactant, and the energy transfer efficiency initially improved with increased surfactant concentration but then decreased significantly when the surfactant reached a higher concentration due to the formation of larger aggregates, which increased the average distance between AO and RhB. Dynamic light scattering demonstrated the existence of these large aggregates. Moreover, simulations using dissipative particle dynamics supported the experimental results.


Assuntos
Transferência Ressonante de Energia de Fluorescência , Corantes Fluorescentes/química , Simulação de Dinâmica Molecular , Tensoativos/síntese química , Laranja de Acridina/química , Ânions/síntese química , Ânions/química , Hidrodinâmica , Micelas , Estrutura Molecular , Rodaminas/química , Tensão Superficial , Tensoativos/química
15.
Molecules ; 15(10): 6983-92, 2010 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-20938408

RESUMO

A Thiazole Orange conjugated with folate derivative was synthesized in two steps. Firstly, folate was coupled with 1-(3-aminopropyl)-4-methylquinolinium bromide to afford folate-methylquinolinium bromide, which then reacted with benzothiazolium to obtain the title folate-conjugated compound. The compound was evaluated by ¹H-NMR MS, TG/DTA and fluorescence spectroscopic methods. The title compound could selectively target folate receptor expressing tumors according to the in vivo fluorescence imaging preliminarily performed on nude mice with breast tumors.


Assuntos
Benzotiazóis , Corantes Fluorescentes , Ácido Fólico , Quinolinas , Animais , Benzotiazóis/síntese química , Benzotiazóis/química , Benzotiazóis/metabolismo , Linhagem Celular Tumoral , Feminino , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/química , Corantes Fluorescentes/metabolismo , Ácido Fólico/síntese química , Ácido Fólico/química , Ácido Fólico/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Estrutura Molecular , Neoplasias/metabolismo , Neoplasias/patologia , Quinolinas/síntese química , Quinolinas/química , Quinolinas/metabolismo , Espectrometria de Fluorescência
16.
Bioorg Med Chem ; 17(2): 585-91, 2009 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-19103495

RESUMO

A series of Thiazole Orange (TO) derivatives were synthesized and modified by introducing different substitutional groups on benzothiazole and 4-methylquinoline All the TO derivatives were confirmed by (1)HNMR and MS. TO derivative bearing NH(2)- was modified by folic acid and used to label breast cancer cells. The phenomenon of fluorescence enhancement was shown by the fluorescence spectrums of TO derivatives and micrographs of the labeled breast cancer cells. It offered a new try in the aspect of labeling cells by the embedded dyes.


Assuntos
Benzotiazóis/síntese química , Neoplasias da Mama/patologia , Corantes Fluorescentes , Quinolinas/síntese química , Benzotiazóis/química , Linhagem Celular Tumoral , Estruturas Celulares , Feminino , Fluorescência , Humanos , Quinolinas/química
17.
J Comb Chem ; 9(6): 943-50, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17877416

RESUMO

A new solid-phase synthesis is shown to be effective in the preparation of cyanine dye Thiazole Orange (TO) and its derivatives, which can be obtained as a traceless cleavage of the Merrifield resin method. The influence of different solvents, substitutional groups, introduced to benzothiazole such as chlorine, methyl, and nitro was extensively studied. The changes of the special characteristic and fluorescence intensity of the TO derivatives were described. The phenomenon of the synergetic effect was also depicted after modifying the TO molecule with chitosan oligosaccharide (CTS) at the end of the alkyl, which can effectively improve the sensitivity of the fluorescent probe.


Assuntos
Benzotiazóis/síntese química , Corantes Fluorescentes/síntese química , Quinolinas/síntese química , Benzotiazóis/química , Estrutura Molecular , Solventes/química , Espectrometria de Fluorescência , Espectrofotometria Infravermelho , Temperatura
18.
J Org Chem ; 68(8): 3295-8, 2003 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-12688805

RESUMO

A new polysiloxane-supported NAD(P)H model, 1-benzyl-1,4-dihydronicotinamide, was designed and synthesized, which can efficiently reduce many activated olefins under mild conditions. The most advantageous features of this new polysiloxane-supported reductant are (i) easy workup and separation of the reaction products and (ii) good potential for recycling use of the reductant, which makes this new polysiloxane-supported NAD(P)H model a promising alternative both in research laboratories and in industrial processes.


Assuntos
Alcenos/química , Modelos Moleculares , NADP , NAD/análogos & derivados , Catálise , Estrutura Molecular , Oxirredução , Siloxanas/química
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