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1.
Plant Cell ; 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38635962

RESUMO

Protein S-acylation catalyzed by protein S-acyl transferases (PATs) is a reversible lipid modification regulating protein targeting, stability, and interaction profiles. PATs are encoded by large gene families in plants, and many proteins including receptor-like cytoplasmic kinases (RLCKs) and receptor-like kinases (RLKs) are subject to S-acylation. However, few PATs have been assigned substrates, and few S-acylated proteins have known upstream enzymes. We report that Arabidopsis (Arabidopsis thaliana) class A PATs redundantly mediate pollen tube guidance and participate in the S-acylation of POLLEN RECEPTOR KINASE1 (PRK1) and LOST IN POLLEN TUBE GUIDANCE1 (LIP1), a critical RLK or RLCK for pollen tube guidance, respectively. PAT1, PAT2, PAT3, PAT4, and PAT8, collectively named PENTAPAT for simplicity, are enriched in pollen and show similar subcellular distribution. Functional loss of PENTAPAT reduces seed set due to male gametophytic defects. Specifically, pentapat pollen tubes are compromised in directional growth. We determine that PRK1 and LIP1 interact with PENTAPAT, and their S-acylation is reduced in pentapat pollen. The plasma membrane (PM) association of LIP1 is reduced in pentapat pollen, whereas point mutations reducing PRK1 S-acylation affect its affinity with its interacting proteins. Our results suggest a key role of S-acylation in pollen tube guidance through modulating PM receptor complexes.

2.
Plant Physiol ; 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38889048

RESUMO

Transcriptional reprogramming is critical for plant immunity. Several calmodulin (CaM)-binding protein 60 (CBP60) family transcription factors (TFs) in Arabidopsis (Arabidopsis thaliana), including CBP60g, Systemic Acquired Resistance Deficient 1 (SARD1), CBP60a, and CBP60b, are critical for and show distinct roles in immunity. However, there are additional CBP60 members whose function is unclear. We report here that Arabidopsis CBP60c-f, four uncharacterized CBP60 members, play redundant roles with CBP60b in the transcriptional regulation of immunity responses, whose pCBP60b-driven expression compensates the loss of CBP60b. By contrast, neither CBP60g nor SARD1 is inter-changeable with CBP60b, suggesting clade-specific functionalization. We further show that function of CBP60b clade TFs relies on DNA-binding domains (DBDs) and CaM-binding domains, suggesting that they are downstream components of calcium signaling. Importantly, we demonstrate that CBP60s encoded in earliest land plant lineage Physcomitrium patens and Selaginella moellendorffii, are functionally homologous to Arabidopsis CBP60b, suggesting that the CBP60b clade contains the prototype TFs of the CBP60 family. Furthermore, tomato and cucumber CBP60b-like genes rescue the defects of Arabidopsis cbp60b and activate the expression of tomato and cucumber SALICYLIC ACID INDUCTION DEFICIIENT2 (SID2) and ENHANCED DISEASE SUSCEPTIBILITY 1 (EDS1) genes, suggesting that immune response pathways centered on CBP60b are also evolutionarily conserved. Together, these findings suggest CBP60b clade transcription factors are functionally conserved in evolution and positively mediate immunity.

3.
Plant Physiol ; 193(1): 140-155, 2023 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-36974907

RESUMO

Pollen germination is a process of polarity establishment, through which a single and unique growth axis is established. Although most of the intracellular activities associated with pollen germination are controlled by RHO OF PLANTs (ROPs) and increased ROP activation accompanies pollen germination, a critical role of ROPs in this process has not yet been demonstrated. Here, by genomic editing of all 4 Arabidopsis (Arabidopsis thaliana) ROPs that are preferentially expressed in pollen, we showed that ROPs are essential for polarity establishment during pollen germination. We further identified and characterized 2 ROP effectors in pollen germination (REGs) through genome-wide interactor screening, boundary of ROP domain (BDR) members BDR8 and BDR9, whose functional loss also resulted in no pollen germination. BDR8 and BDR9 were distributed in the cytosol and the vegetative nucleus of mature pollen grains but redistributed to the plasma membrane (PM) of the germination site and to the apical PM of growing pollen tubes. We demonstrated that the PM redistribution of BDR8 and BDR9 during pollen germination relies on ROPs but not vice versa. Furthermore, enhanced expression of BDR8 partially restored germination of rop1 pollen but had no effects on that of the quadruple rop pollen, supporting their genetic epistasis. Results presented here demonstrate an ROP signaling route essential for pollen germination, which supports evolutionarily conserved roles of Rho GTPases in polarity establishment.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Tubo Polínico , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/fisiologia , Germinação , Tubo Polínico/crescimento & desenvolvimento , Proteínas de Arabidopsis/metabolismo , Infertilidade das Plantas , Epistasia Genética , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Pólen/citologia , Pólen/metabolismo
4.
J Sci Food Agric ; 103(11): 5560-5568, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37061892

RESUMO

BACKGROUND: Dark spots may affect the appearance of fresh noodles during storage, even when made from flour with low ash content. The effect of flour bran content on the degree of dark spot formation in fresh wet noodle sheets (FWNS) is investigated to explain this phenomenon. RESULTS: Confocal laser scanning microscopy (CLSM) observation revealed that the wheat bran particles were responsible for the formation of dark spots on FWNS, with each bran particle core generating a single dark spot. In wheat flours with low ash content, the number of wheat bran particles causing dark spot formation on FWNS was limited, and these particles were not visible to the naked eye until their size exceeded approximately 50 µm. Tropolone, a polyphenol oxidase inhibitor (PubChem CID: 24900578) and dry heating treatment, which inactivates polyphenol oxidase, was found to inhibit or reduce the formation of dark spots. CONCLUSION: Based on these findings, it can be concluded that bran particles, rich in polyphenol oxidase, play a key role in dark spot formation. © 2023 Society of Chemical Industry.


Assuntos
Fibras na Dieta , Farinha , Catecol Oxidase
5.
Analyst ; 144(5): 1696-1703, 2019 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-30657480

RESUMO

In this paper, we introduced a new strategy for converting aggregation-induced emission (AIE) to fluorescence emission in solution into the rational design of new fluorescent probes. Two fluorescent probes based on this strategy, namely, PDAM-Lyso and PDAM-Me, have been synthesized and tested both in vitro and in vivo. The fluorophores of the two probes are both phenothiazine molecules, which link to the diaminomaleonitrile (DAMN) moiety through imine bonds. In the presence of imine bonds, the probes emit red fluorescence in an aqueous solution caused by the AIE effect. As the imine bonds are selectively cut-off by HClO, the DAMN moiety gets removed, inducing blue fluorescence of the reaction product. In this way, the selectivity of the DAMN-based probes toward HClO against metal ions and other reactive oxygen species (ROS) was successfully improved. The imaging of endogenous and exogenous HClO with these two probes reveals that lysosome-targeting probes are of great advantage in the detection of natively generated HClO. Furthermore, the imaging of endogenous HClO in zebrafish suggests that PDAM-Lyso is capable of monitoring the generation of HClO in vivo, illustrating that this strategy is of great significance in designing new probes.


Assuntos
Corantes Fluorescentes/química , Ácido Hipocloroso/análise , Nitrilas/química , Fenotiazinas/química , Animais , Fenômenos Químicos , Fluorescência , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/toxicidade , Células HeLa , Humanos , Ácido Hipocloroso/química , Limite de Detecção , Lisossomos/metabolismo , Camundongos , Microscopia Confocal/métodos , Microscopia de Fluorescência/métodos , Nitrilas/síntese química , Nitrilas/toxicidade , Fenotiazinas/síntese química , Fenotiazinas/toxicidade , Células RAW 264.7 , Peixe-Zebra
6.
J Clin Lab Anal ; 33(9): e23002, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31420917

RESUMO

BACKGROUND: At present, gastric cancer (GC) is a serious threat to human life and health. Non-coding circular RNAs (circRNAs) have been found abnormal expression in multiple tumors. However, circRNAs remain largely unknown in tumor progression. In the present study, we mainly examined the expression, function, and molecular mechanisms of a new circRNAs (hsa_circ_101882) in GC. MATERIALS AND METHODS: The expression of hsa_circ_101882 in GC tissue, corresponding adjacent normal tissues, and GC cell lines was examined by RT-PCR. The function of hsa_circ_101882 in GC was evaluated by MTT assay, cell migration, and invasion assay, colony formation assay, and flow cytometric assay. The effect of hsa_circ_101882 on epithelial-to-mesenchymal transition (EMT)-related gene expression was detected by RT-PCR and Western blot. RESULTS: Hsa_circ_101882 expression levels were significantly increased in GC tissue and GC cell lines. Functionally, low expression of hsa_circ_101882 revealed anti-tumor effects via inhibiting cell growth, migration, and invasion and promoting cell apoptosis. Mechanically, the dysregulated expression of hsa_circ_101882 affects EMT signaling pathway, which was examined by detecting E-cadherin, N-cadherin, vimentin, and Snail expression levels. CONCLUSIONS: Therefore, our research reveals that hsa_circ_101882 is considered a metastasis promoter by activating EMT and may serve as a critical oncogene and potential new biomarker in GC.


Assuntos
Movimento Celular/genética , Transição Epitelial-Mesenquimal/genética , RNA Circular/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Linhagem Celular Tumoral , Regulação para Baixo/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Genes Supressores de Tumor , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , RNA Circular/metabolismo , Regulação para Cima/genética
7.
Analyst ; 143(11): 2641-2647, 2018 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-29756154

RESUMO

Reactive oxygen species (ROS), especially HOCl/ClO-, have been demonstrated to play essential roles in both physiological and pathological processes, and an abnormal level of HOCl/ClO- is related to some diseases. In this work, a very fast responsive (within 30 seconds) porphyrin-based fluorescent probe, TPP-TCF, for ClO- with a NIR emissive wavelength was prepared. This probe exhibited excellent selectivity towards ClO- and would not be interfered with by other ROS and typical nucleophiles. The limit of detection (LOD) for ClO- was evaluated to be 0.29 µM, indicating high sensitivity towards ClO-. In further bioimaging experiments, TPP-TCF displayed low-cytotoxicity and good cell penetrability for recognizing exogenous ClO- in HeLa cells. Moreover, this probe was successfully applied in imaging endogenous ClO- in living animals.


Assuntos
Corantes Fluorescentes , Ácido Hipocloroso/análise , Porfirinas , Animais , Células HeLa , Humanos , Limite de Detecção , Camundongos Nus
8.
BMC Complement Altern Med ; 18(1): 205, 2018 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-29973206

RESUMO

BACKGROUND: Epithelial-to-mesenchymal transition (EMT) plays an important role in the progression of renal interstitial fibrosis, which finally leads to renal failure. Oleanolic acid (OA), an activator of NF-E2-related factor 2 (Nrf2), is reported to attenuate renal fibrosis in mice with unilateral ureteral obstruction. However, the role of OA in the regulation of EMT and the underlying mechanisms remain to be investigated. This study aimed to evaluate the effects of OA on EMT of renal proximal tubular epithelial cell line (NRK-52E) induced by TGF-ß1, and to elucidate its underlying mechanism. METHODS: Cells were incubated with TGF-ß1 in the presence or absence of OA. The epithelial marker E-cadherin, the mesenchymal markers, α-smooth muscle actin (α-SMA), fibronectin, Nrf2, klotho, the signal transducer (p-Smad2/3), EMT initiator (Snail), and ILK were assayed by western blotting. RESULTS: Our results showed that the NRK-52E cells incubated with TGF-ß1 induced EMT with transition to the spindle-like morphology, down-regulated the expression of E-cadherin but up-regulated the expression of α-SMA and fibronectin. However, the treatment with OA reversed all EMT markers in a dose-dependent manner. OA also restored the expression of Nrf2 and klotho, decreased the phosphorylation of Smad2/3, ILK, and Snail in cells which was initiated by TGF-ß1. CONCLUSION: OA can attenuate TGF-ß1 mediate EMT in renal tubular epithelial cells and may be a promising therapeutic agent in the treatment of renal fibrosis.


Assuntos
Transição Epitelial-Mesenquimal/efeitos dos fármacos , Ácido Oleanólico/farmacologia , Fator de Crescimento Transformador beta1/metabolismo , Animais , Linhagem Celular , Ratos , Transdução de Sinais/efeitos dos fármacos
9.
Analyst ; 139(8): 1980-6, 2014 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-24600684

RESUMO

In this study, a turn-on coumarin-based fluorescent probe, 7-hydroxy-6-[(2-hydroxy-naphthalen-1-ylmethylene)-amino]-4-methyl-chroman-2-one (CN), was developed for detecting Al(3+) in aqueous systems. The binding ratio of CN-Al(3+) complexes was determined from the Job plot and ESI-MS data to be 1 : 1. The binding constant (Ka) of Al(3+) binding to CN was calculated to be 9.55 × 10(4) M(-1) from a Benesi-Hildebrand plot and the detection limit was evaluated to be as low as 0.10 µM (LOD = 3σ/slope). CN could be used as an effective fluorescent probe for detecting Al(3+) in living HeLa cells. Moreover, CN could also be applied in the in vivo detection of Al(3+) in zebrafish.


Assuntos
Alumínio/análise , Cumarínicos/química , Corantes Fluorescentes/química , Animais , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Espectroscopia de Ressonância Magnética , Espectrometria de Fluorescência , Espectrometria de Massas por Ionização por Electrospray , Peixe-Zebra
10.
World J Surg Oncol ; 12: 6, 2014 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-24400724

RESUMO

Although invasive thymoma commonly infiltrates neighbouring mediastinal structures, its extension into the superior vena cava (SVC) and consequent SVC occlusion are rare. In such cases, the urgent removal of the thymoma and radical resection of the infiltrated SVC representreasonable options, since induction therapy is time-consuming and useless for symptom resolution. A case of invasive thymoma extending into the SVC and right atrium (RA) with SVC syndrome is reported. The patient underwent a combined resection of the invasive tumor and SVC under cardiopulmonary bypass (CPB), and the SVC and bilateral brachiocephalic vein (BCV) were reconstructed with an autologous pericardial 'Y' conduit. After 40 months of follow-up, the patient showed a patent graft and no tumor recurrence.


Assuntos
Átrios do Coração/cirurgia , Síndrome da Veia Cava Superior/cirurgia , Timoma/cirurgia , Neoplasias do Timo/cirurgia , Idoso , Seguimentos , Átrios do Coração/patologia , Humanos , Masculino , Invasividade Neoplásica , Prognóstico , Síndrome da Veia Cava Superior/patologia , Timoma/patologia , Neoplasias do Timo/patologia , Tomografia Computadorizada por Raios X
11.
Yao Xue Xue Bao ; 49(6): 888-95, 2014 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-25212037

RESUMO

A series of 2-(3-butynoicamidophenyl)benzothiazole derivatives were synthesized starting from 4-fluoro-3-nitrobenzoic acid. Structures of all the synthesized compounds were confirmed by 1H NMR and HR-MS. Their antitumor activities against human tumor cells lines (HCT116, Mia-PaCa2, U87-MG, A549, NCI-H1975) were evaluated by MTT assay. The results revealed that most of the synthesized compounds showed potent activities against HCT116, Mia-PaCa2, U87-MG tumor cells lines. Particularly, compounds 14c and 14h exhibited better activity with IC50 values of 1 x 10(-8) mol x L(-1) against U87-MG and HCT116 respectively. The structure-activity relationship of compounds was also discussed preliminarily.


Assuntos
Antineoplásicos/farmacologia , Benzotiazóis/farmacologia , Antineoplásicos/síntese química , Benzotiazóis/síntese química , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Nitrobenzoatos , Relação Estrutura-Atividade
12.
Plant Sci ; 341: 111998, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38307351

RESUMO

The production of excess and viable pollen grains is critical for reproductive success of flowering plants. Pollen grains are produced within anthers, the male reproductive organ whose development involves precisely controlled cell differentiation, division, and intercellular communication. In Arabidopsis thaliana, specification of an archesporial cell (AC) at four corners of a developing anther, followed by programmed cell divisions, generates four pollen sacs, walled by four cell layers among which the tapetum is in close contact with developing microspores. Tapetum secretes callose-dissolving enzymes to release microspores at early stages and undergoes programmed cell death (PCD) to deliver nutrients and signals for microspore development at later stages. Except for transcription factors, plasma membrane (PM)-associated and secretory peptides have also been demonstrated to mediate anther development. Adaptor protein complexes (AP) recruit both cargos and coat proteins during vesicle trafficking. Arabidopsis AP-1µ/HAPLESS13 (HAP13) is a core component of AP-1 for protein sorting at the trans-Golgi network/early endosomes (TGN/EE). We report here that Arabidopsis HAP13 is critical for pollen sac formation and for sporophytic control of pollen production. Functional loss of HAP13 causes a reduction in pollen sac number. It also results in the dysfunction of tapetum such that secretory function of tapetum at early stages and PCD of tapetum at later stages are both compromised. We further show that the expression of SPL, the polar distribution of auxin maximum, as well as the asymmetric distribution of PIN1 are interfered in hap13 anthers, which in combination may lead to male sterility in hap13.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Proteínas Adaptadoras de Transdução de Sinal , Apoptose , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Transporte Biológico , Comunicação Celular , Flores , Regulação da Expressão Gênica de Plantas
13.
J Orthop Surg Res ; 19(1): 262, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38658987

RESUMO

BACKGROUND: Femoral neck fractures (FNFs) in young adults are usually caused by high-energy trauma, and their treatment remains a challenging issue for orthopedic surgeons. The quality of reduction is considered an important factor in improving the poor prognosis of patients with FNFs. In recent years, positive buttress closed reduction technique has received widespread attention in the treatment of FNFs. This comprehensive literature review is designed to encapsulate the impacts of both non-anatomic and anatomic reduction on the biomechanical stability, clinical outcomes, and postoperative complications in the management of FNFs, conjecture the efficacy of positively braced reduction techniques and provide a thorough summarization of the clinical outcomes. METHODS: In this literature review, we have examined all clinical and biomechanical studies related to the treatment of FNFs using non-anatomical reduction or positive and negative buttress reduction. PubMed, Web of Science, Google Scholar and Embase Library databases were searched systematically for studies published before September 1, 2023. Published literature on fracture reduction techniques for treating FNFs was reviewed. In addition, we evaluated the included literature using the MINORs tool. RESULTS: Although the "arch bridge" structure formed by the positive buttress reduction technique improved the support to the cortical bone and provided a more stable biomechanical structure, no significant differences were noted in the clinical efficacy and incidence of postoperative complications between the positive buttress reduction and anatomical reduction. CONCLUSION: Positive buttress reduction is an effective treatment method for young patients with FNFs. When facing difficult-to-reduce FNF, positive buttress reduction should be considered first, followed by anatomical reduction. However, negative buttress reduction should be avoided.


Assuntos
Fraturas do Colo Femoral , Humanos , Fraturas do Colo Femoral/cirurgia , Resultado do Tratamento , Fenômenos Biomecânicos , Complicações Pós-Operatórias/prevenção & controle , Complicações Pós-Operatórias/etiologia , Redução Fechada/métodos , Fixação Interna de Fraturas/métodos , Adulto , Masculino
14.
Chemistry ; 19(14): 4496-505, 2013 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-23418010

RESUMO

A novel strategy is developed for the fabrication of graphene-CdS (G-CdS) nanocomposites by in situ growth of CdS nanoparticles onto simultaneously reduced graphite oxide, which is noncovalently functionalized by sodium 1-pyrene sulfonate through strong π-π stacking interactions. Subsequently, cobalt 2,9,16,23-tetraaminophthalocyanine (CoTAPc) is self-assembled on the G-CdS nanocomposites through electrostatic interactions to produce phthalocyanine-sensitized G-CdS nanocomposites. The photoactive superstructure enhances the photocurrent generation capability, and presents an efficient photoelectrochemical immunosensing platform for the ultrasensitive detection of the prostate-specific antigen (PSA). The quantitative measurement of PSA is based on the decrease in the photocurrent intensity of the phthalocyanine-sensitized G-CdS nanocomposites, which results from an increase in the steric hindrance due to the formation of the immunocomplex. A linear relationship between the photocurrent decrease and the PSA concentration is obtained in the wide range from 1 pgmL(-1) to 5 µgmL(-1) with a detection limit of 0.63 pgmL(-1). The proposed sensor shows high sensitivity, stability, reproducibility, and can become a promising platform for other biomolecular detection.


Assuntos
Grafite/química , Indóis/química , Nanocompostos/química , Técnicas Biossensoriais/métodos , Humanos , Isoindóis , Limite de Detecção , Masculino , Processos Fotoquímicos , Antígeno Prostático Específico/análise , Reprodutibilidade dos Testes
15.
Surg Endosc ; 27(9): 3412-6, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23529574

RESUMO

BACKGROUND: Aortoesophageal fistula (AEF) is a rare but usually fatal complication of a foreign body in the esophagus. Little effective therapy exists to cure an AEF induced by esophageal foreign body. This report describes the authors' 40 years of experience treating patients with AEF caused by a foreign body and compares different treatments of patients and their clinical outcomes. METHODS: The treatments of five patients with AEF caused by esophageal foreign body impaction were recorded at Wuhan General Hospital of Guangzhou Command from 1970 to 2011. One of these five patients was managed with nonsurgical measures, whereas three were treated by surgery with cardiopulmonary bypass, and one was treated by surgery with endovascular stent-graft repair. RESULTS: All five AEF cases were confirmed by computed tomography, esophagogastroscopy, surgical findings, or two or both. The nonsurgically treated patient died of fatal hemorrhage. Another patient died during the postoperative period because of ventricular fibrillation (he had a history of coronary heart disease before the operation), and still another patient died of fatal hemorrhage during the surgery. The remaining two patients were completely cured by surgery: the one via traditional open thoracotomy with cardiopulmonary bypass and the other by surgery with endovascular stent-graft repair. CONCLUSIONS: The authors' experience indicates that early diagnosis and an aggressive surgical treatment without delay is the only form of effective therapy for AEF. Endovascular stent-graft repair may be a safe and feasible method for treating patients with AEF that has potential as an improved treatment option for AEF.


Assuntos
Doenças da Aorta/etiologia , Doenças da Aorta/cirurgia , Fístula Esofágica/etiologia , Fístula Esofágica/cirurgia , Corpos Estranhos/complicações , Corpos Estranhos/cirurgia , Adolescente , Adulto , Ponte Cardiopulmonar , Procedimentos Endovasculares , Humanos , Masculino , Pessoa de Meia-Idade , Stents , Taxa de Sobrevida , Toracotomia , Resultado do Tratamento
16.
Spectrochim Acta A Mol Biomol Spectrosc ; 302: 123004, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37348275

RESUMO

In this work, we reported a chromogenic and near infrared (NIR) region fluorogenic dual-channel probe NRB, which could visually detect gaseous amines with high sensitivity (eg. 50 and 17 ppt for methylamine (MeNH2) via naked eyes and fluorescence spectrometer respectively). It exhibited a wide fluorescent emission band extending to the NIR region with a peak at 615 nm when stimulated by the MeNH2 solution. The plausible sensing mechanism was proved by mass spectrometry, where the reaction process was based on a nucleophilic substitution between the probe and amines rather than the ester group hydrolysis. Furthermore, NRB was successfully applied to monitor the food freshness (seafood and meat food), because of its low cytotoxicity and excellent photophysical properties. It was worth mentioning that real time monitoring for food quality can be realized visually by using a 365 nm UV lamp. In addition, the probe was stable during the quality guarantee period for perishable packaged food. It was believed that the applied experiments have demonstrated the value of this probe in the practical applications for food safety.


Assuntos
Aminas , Corantes Fluorescentes , Corantes Fluorescentes/química , Colorimetria/métodos , Qualidade dos Alimentos , Carne
17.
World J Clin Cases ; 11(31): 7553-7561, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-38078133

RESUMO

BACKGROUND: Compare the diagnostic performance of ultrasound (US), magnetic resonance imaging (MRI), and serum tumor markers alone or in combination for detecting ovarian tumors. AIM: To investigate the diagnostic value of US, MRI combined with tumor markers in ovarian tumors. METHODS: The data of 110 patients with ovarian tumors, confirmed by surgery and pathology, were collected in our hospital from February 2018 to May 2023. The dataset included 60 cases of benign tumors and 50 cases of malignant tumors. Prior to surgery, all patients underwent preoperative US and MRI examinations, as well as serum tumor marker tests [carbohydrate antigen 125 (CA125), human epididymis protein 4 (HE4)]. The aim of the study was to compare the diagnostic performance of these three methods individually and in combination for ovarian tumors. RESULTS: This study found statistically significant differences in the ultrasonic imaging characteristics between benign and malignant tumors. These differences include echo characteristics, presence or absence of a capsule, blood flow resistance index, clear tumor shape, and blood flow signal display rate (P < 0.05). The apparent diffusion coefficient values of the solid and cystic parts in benign tumors were found to be higher compared to malignant tumors (P < 0.05). Additionally, the time-intensity curve image features of benign and malignant tumors showed significant statistical differences (P < 0.05). The levels of serum CA125 and HE4 in benign tumors were lower than those in malignant tumors (P < 0.05). The combined use of US, MRI, and tumor markers in the diagnosis of ovarian tumors demonstrates higher accuracy, sensitivity, and specificity compared to using each method individually (P < 0.05). CONCLUSION: US, MRI, and tumor markers each have their own advantages and disadvantages when it comes to diagnosing ovarian tumors. However, by combining these three methods, we can significantly enhance the accuracy of ovarian tumor diagnosis, enabling early detection and identification of the tumor's nature, and providing valuable guidance for clinical treatment.

18.
Inorg Chem ; 51(5): 2954-60, 2012 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-22356685

RESUMO

We report here a facile strategy to synthesize the nanocomposite of adenine-modified reduced graphene oxide (AMG) via reaction between adenine and GOCl which is generated from SOCl(2) reacted with graphite oxide (GO). The as-synthesized AMG was characterized by transmission electron microscopy (TEM), atomic force microscopy (AFM), UV-vis absorption spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, Raman spectroscopy, thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), cyclic voltammetry (CV), and galvanostatic discharge analysis. The AMG owns about one adenine group per 53 carbon atoms on a graphene sheet, which improves electronic conductivity compared with reduced graphene oxide (RGO). The AMG displays enhanced supercapacitor performance compared with RGO accompanying good stability and good cycling behavior in the supercapacitor.


Assuntos
Adenina/química , Grafite/química , Nanocompostos/química , Óxidos/química , Nanocompostos/ultraestrutura , Nanotecnologia/métodos , Oxirredução
19.
J Fluoresc ; 22(1): 1-7, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21847525

RESUMO

A donor-acceptor compound based on Rhodanineacetic acid-pyrene derivative (RAAP), which emits weak yellow-green fluorescence in the methanol solution, was investigated. RAAP nanoparticles with a mean diameter of 50-60 nm were prepared by a simple reprecipitation method without surfactants. The observation of RAAP nanoparticles were undertaken through SEM and TEM method. The emission spectra of RAAP nanoparticles are red-shifted (Δ λ(em) = 86 nm) to red region and the intensity is 40-fold higher than that in the methanol solution. Both the J-aggregation and aggregation-induced intramolecular planarization are considered to be the probable mechanism of strong emission for RAAP nanoparticles. The excellent sensibility toward organic vapor which profits from its fluorescence switching behavior is well demonstrated by vapor experiment.


Assuntos
Ácido Acético/química , Nanopartículas/química , Pirenos/química , Rodanina/química , Absorção , Cor , Tamanho da Partícula , Espectrometria de Fluorescência , Volatilização
20.
Zhonghua Nan Ke Xue ; 18(12): 1083-7, 2012 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-23405787

RESUMO

OBJECTIVE: To explore the possibility of injury to the striated urethral sphincter by incision to the anterior lobe region in transurethral prostatectomy. METHODS: We incised the anterior lobe region of 60 patients with benign prostatic hyperplasia (BPH) undergoing transurethral prostatectomy. The patients were divided into four groups according to the incision fields: proximate superficial (group 1), proximate deep (group 2), distal superficial (group 3) and distal deep (group 4). The tissues taken from the anterior lobe region were subjected to HE staining, and the smooth and striated muscles were detected by immunohistochemical identification of smooth muscle actin (SMA) and myoglobin (MYO) in the tissues. The prostate volume, age, and PSA level of the patients were analyzed against their positive or negative results. The relative contents of the striated muscle were compared among groups 2, 3 and 4. The independent-sample between-group t-test was used for statistic analysis. RESULTS: The urethral rhabdosphincter was found in the anterior lobe region, with the smooth muscle intermixed with the striated muscle. The incision injury of the urethral rhabdosphincter was associated with the prostate volume. Increased urethral rhabdosphincter was observed in the anterior lobe region, approaching the apex of the prostate and extending to the urethral lumen. CONCLUSION: The anterior lobe region should not be excessively incised in transurethral prostatectomy so as to avoid direct injury of the striated urethral sphincter, which is especially important for prostates of smaller volume or operation near the apex of the prostate.


Assuntos
Próstata/patologia , Hiperplasia Prostática/patologia , Uretra/patologia , Idoso , Técnicas Histológicas , Humanos , Masculino , Próstata/anatomia & histologia , Hiperplasia Prostática/cirurgia , Ressecção Transuretral da Próstata , Uretra/anatomia & histologia
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