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1.
Sens Actuators B Chem ; 4022024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38559378

RESUMO

Two NAD(P)H-biosensing probes consisting of 1,3,3-trimethyl-3H-indolium and 3-quinolinium acceptors, linked by thiophene, A, and 3,4-ethylenedioxythiophene, B, bridges are detailed. We synthesized probes C and D, replacing the thiophene connection in probe A with phenyl and 2,1,3-benzothiadiazole units, respectively. Probe E was prepared by substituting probe A's 3-quinolinium unit with a 1-methylquinoxalin-1-ium unit. Solutions are non-fluorescent but in the presence of NADH, exhibit near-infrared fluorescence at 742.1 nm and 727.2 nm for probes A and B, respectively, and generate absorbance signals at 690.6 nm and 685.9 nm. In contrast, probes C and D displayed pronounced interference from NADH fluorescence at 450 nm, whereas probe E exhibited minimal fluorescence alterations in response to NAD(P)H. Pre-treatment of A549 cells with glucose in the presence of probe A led to a significant increase in fluorescence intensity. Additionally, subjecting probe A to lactate and pyruvate molecules resulted in opposite changes in NAD(P)H levels, with lactate causing a substantial increase in fluorescence intensity, conversely, pyruvate resulted in a sharp decrease. Treatment of A549 cells with varying concentrations of the drugs cisplatin, gemcitabine, and camptothecin (5, 10, and 20 µM) led to a concentration-dependent increase in intracellular fluorescence intensity, signifying a rise in NAD(P)H levels. Finally, fruit fly larvae were treated with different concentrations of NADH and cisplatin illustrating applicability to live organisms. The results demonstrated a direct correlation between fluorescence intensity and the concentration of NADH and cisplatin, respectively, further confirming the efficacy of probe A in sensing changes in NAD(P)H levels within a whole organism.

2.
J Mater Chem B ; 12(2): 448-465, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38063074

RESUMO

A series of near-infrared fluorescent probes, labeled A to E, were developed by combining electron-rich thiophene and 3,4-ethylenedioxythiophene bridges with 3-quinolinium and various electron deficient groups, enabling the sensing of NAD(P)H. Probes A and B exhibit absorptions and emissions in the near-infrared range, offering advantages such as minimal interference from autofluorescence, negligible photo impairment in cells and tissues, and exceptional tissue penetration. These probes show negligible fluorescence when NADH is not present, and their absorption maxima are at 438 nm and 470 nm, respectively. In contrast, probes C-E feature absorption maxima at 450, 334 and 581 nm, respectively. Added NADH triggers the transformation of the electron-deficient 3-quinolinium units into electron-rich 1,4-dihydroquinoline units resulting in fluorescence responses which were established at 748, 730, 575, 625 and 661 for probes AH-EH, respectively, at detection limits of 0.15 µM and 0.07 µM for probes A and B, respectively. Optimized geometries based on theoretical calculations reveal non-planar geometries for probes A-E due to twisting of the 3-quinolinium and benzothiazolium units bonded to the central thiophene group, which all attain planarity upon addition of hydride resulting in absorption and fluorescence in the near-IR region for probes AH and BH in contrast to probes CH-EH which depict fluorescence in the visible range. Probe A has been successfully employed to monitor NAD(P)H levels in glycolysis and specific mitochondrial targeting. Furthermore, it has been used to assess the influence of lactate and pyruvate on the levels of NAD(P)H, to explore how hypoxia in cancer cells can elevate levels of NAD(P)H, and to visualize changes in levels of NAD(P)H under hypoxic conditions with CoCl2 treatment. Additionally, probe A has facilitated the examination of the potential impact of chemotherapy drugs, namely gemcitabine, camptothecin, and cisplatin, on metabolic processes and energy generation within cancer cells by affecting NAD(P)H levels. Treatment of A549 cancer cells with these drugs has been shown to increase NAD(P)H levels, which may contribute to their anticancer effects ultimately leading to programmed cell death or apoptosis. Moreover, probe A has been successfully employed in monitoring NAD(P)H level changes in D. melanogaster larvae treated with cisplatin.


Assuntos
NAD , Neoplasias , Animais , NAD/metabolismo , Cisplatino , Drosophila melanogaster/metabolismo , Elétrons , Mitocôndrias/metabolismo , Corantes Fluorescentes/metabolismo , Ácido Pirúvico/metabolismo , Tiofenos , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo
3.
ACS Appl Bio Mater ; 6(8): 3199-3212, 2023 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-37556116

RESUMO

We have developed two highly sensitive cyanine dyes, which we refer to as probes A and B. These dyes are capable of quick and sensitive sensing of NAD(P)H. The dyes were fabricated by connecting benzothiazolium and 2,3-dimethylnaphtho[1,2-d]thiazol-3-ium units to 3-quinolinium through a vinyl bond. In the absence of NAD(P)H, both probes have low fluorescence and absorption peaks at 370 and 400 nm, correspondingly. This is because of their two electron-withdrawing acceptor systems with high charge densities. However, when NAD(P)H reduces the probes' electron-withdrawing 3-quinolinium units to electron-donating 1,4-dihydroquinoline units, the probes absorb at 533 and 535 nm and fluoresce at 572 and 586 nm for A and B correspondingly. This creates well-defined donor-π-acceptor cyanine dyes. We successfully used probe A to monitor NAD(P)H levels in live cells during glycolysis, under hypoxic conditions induced by CoCl2 treatment and after treatment with cancer drugs, including cisplatin, camptothecin, and gemcitabine. Probe A was also employed to visualize NAD(P)H in Drosophila melanogaster first-instar larvae. We observed an increase in NAD(P)H levels in A549 cancer cells both under hypoxic conditions and after treatment with cancer drugs, including cisplatin, camptothecin, and gemcitabine.


Assuntos
Drosophila melanogaster , NAD , Animais , NAD/química , Corantes Fluorescentes/química , Cisplatino , Mitocôndrias
4.
J Mater Chem B ; 11(27): 6296-6307, 2023 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-37249441

RESUMO

We report a novel method for synthesizing red and deep red cyanine dyes with large Stokes shifts, probes A and B, for live cell NAD(P)H detection. The probes were prepared using thiophene-based organic dyes featuring a π-conjugated bridge of thiophene and 3,4-ethylenedioxythiophene units linking the 1-methylquinolinium acceptor and formyl acceptor, respectively. These probes display weak absorption peaks at 315 nm (A) and 334 nm (B) and negligible fluorescence in the absence of NADH. However, upon the presence of NADH, new absorption and fluorescence peaks appear at 477 nm and 619 nm for probe A and at 486 nm and 576 nm for probe B, respectively. This is due to the NADH-facilitated reduction of the 1-methylquinolinium unit into 1-methyl-1,4-dihydroquinoline, which then acts as the electron donor for the probes, leading to the formation of well-defined electron donor-acceptor dye systems. Probe A has a large Stokes shift of 144 nm, which allows for better separation between the excitation and emission spectra, reducing spectral overlap and improving the accuracy of fluorescence measurements. The probes are highly selective for NAD(P)H, water-soluble, biocompatible, and easily permeable to cells. They are also photostable and were successfully used to monitor changes in NADH concentration in live cells during glycolysis in the presence of glucose, lactate, and pyruvate, treatment of FCCP and cancer drug cisplatin, and under hypoxia triggered by CoCl2. Furthermore, the probes were able to image NAD(P)H in Drosophila melanogaster larvae. Notably, cisplatin treatment increased the NAD(P)H concentration in A459 cells over time. Overall, this work presents a significant advancement in the field of live cell imaging by providing a simple and cost-effective method for detecting changes in NAD(P)H concentration under varying chemical stimuli.


Assuntos
Corantes Fluorescentes , NAD , Animais , Tiofenos , Cisplatino , Drosophila melanogaster
5.
J Mater Chem B ; 11(13): 2852-2861, 2023 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-36808460

RESUMO

We describe a simple but efficient approach to make fluorescent probes A and B based on rhodol dyes incorporated with salicyaldehyde moiety for monitoring pH changes in mitochondria under oxidative stresses and hypoxia conditions, and for tracking mitophagy processes. Probes A and B possess pKa values (pKa ≈ 6.41 and 6.83 respectively) near physiological pH and exhibit decent mitochondria-targeted capabilities, low cytotoxicity, and useful ratiometric and reversible pH responses, which make the probes appropriate for monitoring pH fluctuations of mitochondria in living cells with built-in calibration feature for quantitative analysis. The probes have been effectively useful for the ratiometric determination of pH variations of mitochondria under the stimuli of carbonyl cyanide-4(trifluoromethoxy)phenylhydrazone (FCCP), hydrogen peroxide (H2O2), and N-acetyl cysteine (NAC), and during mitophagy triggered by cell nutrient deprivation, and under hypoxia conditions with cobalt chloride (CoCl2) treatment in living cells. In addition, probe A was efficient in visualizing pH changes in the larvae of fruit flies.


Assuntos
Peróxido de Hidrogênio , Mitofagia , Humanos , Células HeLa , Corantes Fluorescentes , Hipóxia , Concentração de Íons de Hidrogênio
6.
Spectrochim Acta A Mol Biomol Spectrosc ; 289: 122189, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36512960

RESUMO

A fluorescent probe was developed for the detection of phosgene based on 1,8-naphthalimide, of which o-diaminobenzene was used as the recognition moiety. The probe does not fluoresce due to nonradiative decay. The probe reacts rapidly with phosgene via an intramolecular cyclization reaction, which induces large fluorescence due to increased rigidity in the resulting molecule and a low detection limit (0.23 nM). This probe has excellent selectivity for phosgene against competing interference analytes and, in the form of probe-loaded test paper, is an extremely sensitive method for phosgene sensing in the gas phase below 1 ppm concentrations.


Assuntos
Fosgênio , Gases , Corantes Fluorescentes , Naftalimidas , Espectrometria de Fluorescência/métodos
7.
Acta Obstet Gynecol Scand ; 101(12): 1450-1457, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36203317

RESUMO

INTRODUCTION: Hysterectomy now belongs to standard gynecological procedures. Moreover, a shift towards laparoscopic techniques is ever more apparent as they provide many advantages such as less traumatization and shorter convalescence. Large uteri are still mentioned as contraindications for laparoscopic hysterectomy even though those patients might benefit from the lower morbidity associated with minimal invasive techniques. In this study, the largest reported so far, we analyzed intraoperative and postoperative complications as well as the surgeon's experience of laparoscopic assisted supracervical hysterectomy (LASH) in patients with a uterus weight over 500 g. MATERIAL AND METHODS: The present retrospective study, between June 27, 1998 and August 31, 2019, evaluates 1274 patients with a uterus weight over 500 g who were treated with LASH for benign uterine diseases at the Clinic for Minimal Invasive Surgery (Berlin, Germany). All surgeries were performed by one of four in-house surgeons with experience in LASH: they had performed at least 500 LASH procedures before the study. Patients receiving surgical treatment for malignant tumors were not included in the study. Major and minor intraoperative and postoperative complications were recorded and evaluated. Additionally, medical files were evaluated for demographic data, American Society of Anesthesiologists score (I-IV), name of the surgeon, duration and indication for surgery, history of previous gynecological procedures and concomitant surgical interventions, weight of removed uterine tissue, duration of postoperative hospitalization in patients with complications, intraoperative conversion from laparoscopy to laparotomy, and malignancy rate. RESULTS: The mean age was 47.0 ± 7.3 years and mean body mass index was 25.6 ± 7.1 kg/m2 . Average parity was 1.04 ± 1.57. Average uterus weight was 761.8 ± 317.9 g (500-4065 g). The mean duration of surgery was 96.9 ± 49.5 min; 54% of all patients were treated without concomitant intervention, conversion rate was 2.12%. The malignancy rate was 0.4% and the complication rate was 6.81% with 1.36% intraoperative complications and 5.45% postoperative complications. CONCLUSIONS: The overall low complication and malignancy rates observed in this study allow us to present LASH as a safe and efficient alternative laparoscopic approach to remove uteri of any size in the hands of experienced surgeons.


Assuntos
Laparoscopia , Leiomioma , Cirurgiões , Feminino , Humanos , Adulto , Pessoa de Meia-Idade , Estudos Retrospectivos , Histerectomia/métodos , Útero/cirurgia , Útero/patologia , Laparoscopia/métodos , Leiomioma/cirurgia , Leiomioma/patologia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia
8.
ACS Appl Bio Mater ; 2022 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-35994395

RESUMO

Three fluorescent probes A, B, and C that function in the near-infrared wavelengths and utilize pseudo xanthene platforms with an oxygen atom at the 10-position replaced by a [Me-N]2- group have been created to identify hypoxia via nitroreductase determinations at the 0.04, 0.10, and 0.19 ng/mL levels. Theoretical calculations suggest that the probes are not planar due to steric interactions. Absorptions of photons result in the transition of electron density from the indoline moieties to delocalized orbitals on the anthranilic section, ending up on the nitro groups of the electron-poor (i.e., nonreduced) probes (i.e., A, B, and C), whereas those for the more electron-rich (i.e., reduced) probes consisted of movement from the indoline groups to the right side of the anthranilic sections, resulting in a shift in absorption.

9.
J Clin Med ; 11(8)2022 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-35456285

RESUMO

Standards of care offer doctors and patients the confidence that an established quality, evidence-based, care is provided, and represent a tool for optimal responding to the population's needs. It is expected that they will increasingly express a multimodal relationship with gynecologic laparoscopy. Laparoscopy is, now, a standard procedure in operative gynecology, standards are embedded in many laparoscopic procedures, standardization of the skills/competency assessment has been progressively developed, and the proof of competency in laparoscopy may become a standard of care. A continuous development of surgical education includes standard equipment (that may bring value for future advance), standardized training, testing (and performance) assessment, educational process and outcome monitoring/evaluation, patients' care, and protection, etc. Standards of care and training have a reciprocally sustaining relationship, as training is an essential component of standards of care while care is provided at higher standards after a structured training and as credentialing/certification reunites the two. It is envisaged that through development and implementation, the European wide standards of care in laparoscopic surgery (in close harmonization with personalized medicine) would lead to effective delivery of better clinical services and provide excellent training and education.

10.
Methods ; 204: 22-28, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35381337

RESUMO

A near-infrared fluorescent probe was prepared for selective detection of reduced nicotinamide adenine dinucleotide (NADH) in live cells. The probe turns off the fluorescence with a closed spironolactone switch. However, reduction of the probe by NADH turns on fluorescence at 740 nm. Theoretical calculations suggest a more planar arrangement between the rhodamine and quinoline moieties with increased π-delocalization resulting from reduction.


Assuntos
Corantes Fluorescentes , NAD , Fluorescência , Células HeLa , Humanos , Rodaminas
11.
Spectrochim Acta A Mol Biomol Spectrosc ; 274: 121074, 2022 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-35257990

RESUMO

A novel two-photon fluorogenic probe has been developed to detect formaldehyde with fast response, low cytotoxicity, and excellent selectivity. This probe exhibits a strong turn-on fluorescence response to formaldehyde under excitation at 370 nm and has been successfully applied to detect formaldehyde in living cells. Theoretical calculations at the B3LYP/6-31 + G(d,p), APFD/6-311++G, and APFD/6-311 + G(2d,p) levels of theory for the absorption and emission wavelengths of the probes were in agreement with those obtained experimentally.


Assuntos
Corantes Fluorescentes , Bases de Schiff , Cumarínicos , Formaldeído , Células HeLa , Humanos
12.
J Clin Med ; 12(1)2022 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-36615096

RESUMO

Recent findings suggest that high-grade serous ovarian cancer can originate in the fallopian tube. Not only has that made the identification of precursor lesions pivotal in early detection and prevention of these cancers, prophylactic salpingectomy alongside hysterectomy for benign indications has been increasingly proposed as well. The present prospective single-center study included 273 women who underwent opportunistic salpingectomy alongside laparoscopic supracervical hysterectomy. Uterine and tubal histopathological results as well as intra- and postoperative complications were evaluated. The complication rate was 3.3%, of which none were caused by salpingectomy. Uterine histopathology diagnosed 181 patients (66.8%) with uterine myomas, 60 patients (22.1%) with adenomyosis, 29 patients (10.7%) with adenomyomatosis, and, 1 patient (0.4%) without pathological abnormality. p53 signatures were detected in 221 right fallopian tubes (80.9%) and in 229 left tubes (83.9%). In total, 8 patients showed bilateral STIL (2.9%), whereas in 1 patient (0.4%) STIL was detected in the left tube only. No STIC were detected. Laparoscopic opportunistic salpingectomy is demonstrated to be both safe and feasible. It appears to be promising to reduce the risk for ovarian cancer, yet more studies are needed to undoubtedly confirm this.

13.
J Mater Chem B ; 9(25): 5150-5161, 2021 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-34132313

RESUMO

A near-infrared reactive cyanine platform (probe A) was prepared by condensation of 9-chloro-1,2,3,4-tetrahydro-10-methyl-acridinium iodide with Fisher's aldehyde. A near-infrared fluorescent probe (probe B) was prepared by modifying a reactive chlorine atom of probe A with tert-butyl(2-aminoethyl)carbamate through a substitution reaction. The deprotection of the Boc group of probe B was achieved under an acidic condition, affording an amine-functionalized cyanine dye (probe C). A near-infrared ratiometric fluorescent probe (probe D) for mitochondrial pH detection was synthesized by conjugating a FRET coumarin donor to a FRET cyanine acceptor (probe C) through an amide bond connection. Probe A shows low fluorescence of 2% due to an electron-withdrawing chlorine atom, while probes B-D display high fluorescence quantum yields of 60%, 32%, and 35% in aqueous solutions containing 10% ethanol, respectively. Probes B-D show strong fluorescence with push-pull molecular structures in neutral and basic pH conditions. However, protonation of the probe's second amine at the 9-position under acidic condition disrupts the push-pull feature of the probes, resulting in fluorescence quenching of the new cyanine fluorophores. The probes can selectively stain mitochondria, while probe D was employed to detect pH changes in HeLa cells and Drosophila melanogaster first-instar larvae.


Assuntos
Carbocianinas/química , Corantes Fluorescentes/química , Mitocôndrias/química , Animais , Drosophila melanogaster , Transferência Ressonante de Energia de Fluorescência , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Raios Infravermelhos
14.
Chembiochem ; 22(13): 2282-2291, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33983667

RESUMO

Abnormal levels of glutathione, a cellular antioxidant, can lead to a variety of diseases. We have constructed a near-infrared ratiometric fluorescent probe to detect glutathione concentrations in biological samples. The probe consists of a coumarin donor, which is connected through a disulfide-tethered linker to a rhodamine acceptor. Under the excitation of the coumarin donor at 405 nm, the probe shows weak visible fluorescence of the coumarin donor at 470 nm and strong near-infrared fluorescence of the rhodamine acceptor at 652 nm due to efficient Forster resonance energy transfer (FRET) from the donor to the acceptor. Glutathione breaks the disulfide bond through reduction, which results in a dramatic increase in coumarin fluorescence and a corresponding decrease in rhodamine fluorescence. The probe possesses excellent cell permeability, biocompatibility, and good ratiometric fluorescence responses to glutathione and cysteine with a self-calibration capability. The probe was utilized to ratiometrically visualize glutathione concentration alterations in HeLa cells and Drosophila melanogaster larvae.


Assuntos
Cumarínicos/química , Dissulfetos/química , Transferência Ressonante de Energia de Fluorescência , Corantes Fluorescentes/química , Glutationa/análise , Rodaminas/química , Animais , Drosophila melanogaster , Corantes Fluorescentes/síntese química , Células HeLa , Humanos , Estrutura Molecular , Células Tumorais Cultivadas
15.
Molecules ; 26(7)2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33917350

RESUMO

Ratiometric near-infrared fluorescent probes (AH+ and BH+) have been prepared for pH determination in mitochondria by attaching dithioacetal and formal residues onto a hemicyanine dye. The reactive formyl group on probe BH+ allows for retention inside mitochondria as it can react with a protein primary amine residue to form an imine under slightly basic pH 8.0. Probes AH+ and BH+ display ratiometric fluorescent responses to pH changes through the protonation and deprotonaton of a hydroxy group in hemicyanine dyes with experimentally determined pKa values of 6.85 and 6.49, respectively. Calculated pKa values from a variety of theoretical methods indicated that the SMDBONDI method of accounting for solvent and van der Waals radii plus including a water molecule located near the site of protonation produced the closest overall agreement with the experimental values at 7.33 and 6.14 for AH+ and BH+ respectively.


Assuntos
Carbocianinas/química , Corantes Fluorescentes/química , Mitocôndrias/metabolismo , Morte Celular , Corantes Fluorescentes/síntese química , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Fenômenos Ópticos , Espectrometria de Fluorescência , Água/química
16.
J Mater Chem B ; 9(3): 857-863, 2021 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-33367439

RESUMO

A near-infrared fluorescent probe (AH+) has been prepared by incorporating an oxazolidine switch into a near-infrared hemicyanine dye. The probe shows fast and sensitive responses to pH from an oxazolidine switch to the hemicyanine dye upon pH decreases from 10.0 to 5.0. The probe shows good photostability, low cytotoxicity, and reversible fluorescence responses to pH changes with a pKa value of 7.6. It has been successfully used to determine pH changes in mitochondria.


Assuntos
Carbocianinas/química , Corantes Fluorescentes/química , Oxazóis/química , Carbocianinas/síntese química , Carbocianinas/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Teoria da Densidade Funcional , Relação Dose-Resposta a Droga , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/farmacologia , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Mitocôndrias/efeitos dos fármacos , Estrutura Molecular , Oxazóis/farmacologia , Tamanho da Partícula , Espectrometria de Fluorescência , Propriedades de Superfície
17.
ACS Appl Mater Interfaces ; 12(18): 20172-20179, 2020 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-32255330

RESUMO

A cell membrane-specific fluorescent probe was prepared by conjugating a coumarin dye with a tetraphenylethene (TPE) derivative through an α,ß-unsaturated ketone connection. The probe has two absorptions: one from the TPE moiety at 300 nm and a second one due to the coumarin moiety at 458.5 nm. The probe fluoresces at 470 nm in tetrahydrofuran (THF) solution. The probe exhibits a useful aggregation-induced emission (AIE) property. A gradual increase in the water content of a THF solution causes a significant decrease and 12 nm red shift in the fluorescence peak at 470 nm, giving rise to a new strong fluorescence peak at 591 nm at a 95% water content. The probe is hydrophobic with an AIE property and binds to cell membranes, resulting in 591 nm fluorescence upon implantation into cells. The probe possesses a long retention time despite the lack of a long, cell membrane-anchored hydrophobic alkyl chain, which is typical for traditional membrane-specific probes. Our probe also displays low cytotoxicity and excellent photostability.


Assuntos
Membrana Celular/metabolismo , Cumarínicos/química , Corantes Fluorescentes/química , Animais , Linhagem Celular Tumoral , Cumarínicos/síntese química , Cumarínicos/toxicidade , Drosophila melanogaster , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/toxicidade , Humanos , Interações Hidrofóbicas e Hidrofílicas , Larva , Microscopia Confocal , Microscopia de Fluorescência , Coloração e Rotulagem/métodos
18.
J Mater Chem B ; 8(8): 1603-1615, 2020 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-32055810

RESUMO

Two ratiometric near-infrared fluorescent probes have been developed to selectively detect mitochondrial pH changes based on highly efficient through-bond energy transfer (TBET) from cyanine donors to near-infrared hemicyanine acceptors. The probes consist of identical cyanine donors connected to different hemicyanine acceptors with a spirolactam ring structure linked via a biphenyl linkage. At neutral or basic pH, the probes display only fluorescence of the cyanine donors when they are excited at 520 nm. However, acidic pH conditions trigger spirolactam ring opening, leading to increased π-conjugation of the hemicyanine acceptors, resulting in new near-infrared fluorescence peaks at 740 nm and 780 nm for probes A and B, respectively. This results in ratiometric fluorescence responses of the probes to pH changes indicated by decreases of the donor fluorescence and increases of the acceptor fluorescence under donor excitation at 520 nm due to a highly efficient TBET from the donors to the acceptors. The probes only show cyanine donor fluorescence in alkaline-pH mitochondria. However, the probes show moderate fluorescence decreases of the cyanine donor and considerable fluorescence increases of hemicyanine acceptors during the mitophagy process induced by nutrient starvation or under drug treatment. The probes display rapid, selective, and sensitive responses to pH changes over metal ions, good membrane penetration, good photostability, large pseudo-Stokes shifts, low cytotoxicity, mitochondria-targeting, and mitophagy-tracking capabilities.


Assuntos
Carbocianinas/química , Corantes Fluorescentes/química , Mitocôndrias/química , Mitofagia , Animais , Sobrevivência Celular/efeitos dos fármacos , Drosophila melanogaster/química , Drosophila melanogaster/crescimento & desenvolvimento , Drosophila melanogaster/metabolismo , Transferência de Energia , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/farmacologia , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Larva/química , Larva/metabolismo , Microscopia de Fluorescência , Teoria Quântica , Espectrometria de Fluorescência
20.
J Obstet Gynaecol India ; 69(Suppl 2): 188-193, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31686755

RESUMO

BACKGROUND AND PURPOSE: Since April 2014, the FDA warns against the use of morcellation during minimally invasive uterine surgery because of the risk of occult malignant spreading in the abdominal cavity. It is clear, however, that more studies are needed to define the incidence of occult uterine cancers, its risk factors, preoperative identification and postoperative follow-up. The present retrospective single-arm study defines the prevalence of occult uterine malignancies in a large group of patients treated with hysterectomy or myomectomy for benign indications. METHODS: In the year of 2014, 1498 women admitted for a myomectomy or hysterectomy in benign conditions at the clinic of minimally invasive surgery (Minimal Invasive Chirurgie or MIC) in Berlin (Germany) were included in this study. The morcellated uterine specimens of operated patients were histologically analyzed for the presence of cancerous tissue. RESULTS: We detected malignancies in three of the 1498 women (0.2%): two patients had endometrial cancer, while we observed cervical cancer in situ in the third patient. No sarcoma was found. CONCLUSION: We detected a very low prevalence of occult uterine malignancy which is in line with several other recent studies. To define a clear policy on the use of morcellation, more studies are required. In the meantime, patients should be informed about the risks of morcellation in case of undetected cancer prior to surgery.

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