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1.
Adv Mater ; 36(30): e2403758, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38733567

RESUMO

Wearable bioelectronics represents a significant breakthrough in healthcare settings, particularly in (bio)sensing which offers an alternative way to track individual health for diagnostics and therapy. However, there has been no notable improvement in the field of cancer, particularly for skin cancer. Here, a wearable bioelectronic patch is established for transdermal sensing of the melanoma biomarker, tyrosinase (Tyr), using a microneedle array integrated with a surface-bound chemo-responsive smart probe to enable target-specific electrochemical detection of Tyr directly from human skin tissue. The results presented herein demonstrate the feasibility of a transdermal microneedle sensor for direct quantification of enzyme biomarkers in an ex vivo skin model. Initial performance analysis of the transdermal microneedle sensor proves that the designed methodology can be an alternative for fast and reliable diagnosis of melanoma and the evaluation of skin moles. The innovative approach presented here may revolutionize the landscape of skin monitoring by offering a nondisruptive means for continuous surveillance and timely intervention of skin anomalies, such as inflammatory skin diseases or allergies and can be extended to the screening of multiple responses of complementary biomarkers with simple modification in device design.


Assuntos
Monofenol Mono-Oxigenase , Agulhas , Dispositivos Eletrônicos Vestíveis , Humanos , Monofenol Mono-Oxigenase/metabolismo , Pele/metabolismo , Técnicas Biossensoriais/métodos , Técnicas Biossensoriais/instrumentação , Biomarcadores/metabolismo , Biomarcadores/análise , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia , Adesivo Transdérmico , Melanoma/metabolismo , Epiderme/metabolismo , Técnicas Eletroquímicas/métodos
2.
Talanta ; 271: 125669, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38241925

RESUMO

A significant compound in living organisms, hydrogen peroxide (H2O2) plays a dual role as a signalling molecule in cellular communication and as a pivotal biomarker in assessing disease and oxidative stress. Thus, the detection of abnormal changes in H2O2 levels is essential to understanding its function and involvement in biological systems. The growing demand to meet the specific needs for applications, particularly in biological systems, has sharpened focus on highly sensitive, highly selective molecular sensors and, in turn, heightened interest in these diagnostic tools with innovative designs. In our study, 2-aminophenalenone (2-AP) was used for the first time as a fluorophore in a fluorescent probe. The 2-APB molecule obtained from the reaction of 2-AP with 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl) benzyl chloroformate exhibited a highly selective and sensitive (i.e. 62 nM) detection profile for H2O2 compared with the other reactive oxygen species, anions, and metal cations. Moreover, offering naked-eye detection in aqueous solutions, 2-APB demonstrated excellent sensing performance, detection and real-time monitoring in relation to exogenous H2O2 in cells and endogenous H2O2 in zebrafish embryos.


Assuntos
Corantes Fluorescentes , Peróxido de Hidrogênio , Animais , Peixe-Zebra , Espécies Reativas de Oxigênio , Estresse Oxidativo
3.
Org Biomol Chem ; 21(39): 7880-7885, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37740321

RESUMO

A BODIPY-based fluorophore decorated with a gold specific reactive handle (e.g., 2-alkynylallyl alcohol) displayed a ratiometric fluorescence change in response to Au3+ ions with extraordinary selectivity over other competing metal species, including Hg2+, Cu2+, Zn2+ and Pd2+. By way of a gold-catalyzed intramolecular cyclisation-isomerisation reaction sequence, a BODIPY construct with an extended π-conjugation transformed into a new structure with a relatively short π-system. This unique chemical transformation was accompanied by, and resulted in, a dramatic shift in the emission and absorption wavelength, which could be monitored as distinct changes in the color of the solution's emission. Apart from its outstanding analytical performance in solution, including a quick response time (<10 s), unique specificity, a high-fold ratiometric change (62-fold), and a remarkably low detection limit (358 nM), the probe also proved useful in monitoring Au3+ ions in human cells and plants (e.g., Nicotiana benthamiana).

4.
J Fluoresc ; 33(2): 707-712, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36507999

RESUMO

A phenalenone based "turn on" probe was developed for selective and sensitive detection of Fe3+ ions in aqueous solutions. The thiophene-2-carboxaldehyde (receptor unit) was integrated into the 6-amino-1-phenalenone (6-AP) (signal reporter unit) through the C = N bond formation. The probe, 6-APT, operated through subsequent hydrolysis of the C = N bond induced by the coordination of Fe3+ ions to the heteroatoms to form highly fluorescent 6-AP. The probe displayed remarkable characteristics such as rapid response time (< 1 min), high analyte selectivity, and low limit of detection (1.3 µM). The sensing approach offered an accurate method for the detection of Fe3+ ions in real water samples (tap water and drinking water). In addition to the fluorometric response, the presence of Fe3+ ions can be monitored under daylight by the change in the color of the solution. Importantly, this study is the first example of a phenalenone-based sensor developed for metal ion sensing in literature.

5.
Turk J Chem ; 46(2): 523-529, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-38143477

RESUMO

A new "turn on" fluorescent probe for the rapid and selective detection of Au3+ ions over other metal ions was developed. The probe design was constructed on a BODIPY-2-aminopyridine skeleton showing a weak fluorescence emission signal which increased substantially after the coordination of Au3+ ions. The probe displayed remarkable sensing performances such as a low limit of detection (17 nM), a short response time (<1 min), and ability in a wide range of pH's (6-11). The designed probe was found to have 2:1 coordination stoichiometry according to Job's plot analysis and most importantly to interact reversibly with Au3+ ions.

7.
J BUON ; 26(1): 196-203, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33721452

RESUMO

PURPOSE: The purpose of this study was to compare the multifocal (MF)/multicentric (MC) breast cancers with unifocal (UF) breast cancers in terms of tumour characteristics, treatment methods, loco-regional recurrence and survival rates. METHODS: Patients who were treated with a diagnosis of early-stage breast cancer (stage I,II) and had regular follow-up were included in the study. MF tumours were defined as having more than one tumour focus in the same quadrant, whereas MC tumours refered to the presence of more than one tumour focus in different quadrants. RESULTS: In total, 1865 patients with invasive breast cancer were evaluated, 1493 (80.1%) of whom had UF cancer, 330 (17.7%) had MF cancer, and 42 (2.3%) had MC cancer. After comparing the groups with each other, it was seen that MF and MC breast cancers occurred more often at early ages and that lymph node invasion (LNI) was greater. No differences were seen between the 3 groups in terms of local recurrence-free survival (RFS) and overall survival (OS) rates . In multivariate analysis, it was found that MF and MC tumours had no impact on local recurrence and OS. In multivariate analysis, it was understood that HER2 positivity and triple-negative breast cancer (TNBC) had an impact on local recurrence, and age, lymphovascular invasion (LVI), T3 tumour, lymph node positivity and TNBC subtype had an impact on OS. CONCLUSION: Although MC and MF tumours show aggressive features such as high lymph node positivity and LVI, they have similar loco-regional recurrence and survival rates to UF tumours.


Assuntos
Neoplasias da Mama/patologia , Neoplasias da Mama/mortalidade , Feminino , Humanos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Taxa de Sobrevida
8.
Chem Commun (Camb) ; 57(15): 1899-1902, 2021 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-33491716

RESUMO

The clinically used antifungal polyene amphotericin B was conjugated, via the mycosamine and the aglycon moieties, to fluorophores. The Cy5 conjugated probe showed selective labelling of fungi in the presence of bacteria, allowing multiplexed imaging and identification of microbial species in a co-culture of fungi and Gram-positive and Gram-negative bacteria.


Assuntos
Anfotericina B/química , Corantes Fluorescentes/química , Fungos/isolamento & purificação , Antifúngicos , Bactérias , Técnicas de Cocultura , Microscopia Confocal/métodos , Estrutura Molecular
9.
Eur J Nucl Med Mol Imaging ; 48(3): 800-807, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32915268

RESUMO

PURPOSE: The relentless rise in antimicrobial resistance is a major societal challenge and requires, as part of its solution, a better understanding of bacterial colonization and infection. To facilitate this, we developed a highly efficient no-wash red optical molecular imaging agent that enables the rapid, selective, and specific visualization of Gram-positive bacteria through a bespoke optical fiber-based delivery/imaging endoscopic device. METHODS: We rationally designed a no-wash, red, Gram-positive-specific molecular imaging agent (Merocy-Van) based on vancomycin and an environmental merocyanine dye. We demonstrated the specificity and utility of the imaging agent in escalating in vitro and ex vivo whole human lung models (n = 3), utilizing a bespoke fiber-based delivery and imaging device, coupled to a wide-field, two-color endomicroscopy system. RESULTS: The imaging agent (Merocy-Van) was specific to Gram-positive bacteria and enabled no-wash imaging of S. aureus within the alveolar space of whole ex vivo human lungs within 60 s of delivery into the field-of-view, using the novel imaging/delivery endomicroscopy device. CONCLUSION: This platform enables the rapid and specific detection of Gram-positive bacteria in the human lung.


Assuntos
Fibras Ópticas , Staphylococcus aureus , Endoscópios , Bactérias Gram-Positivas , Humanos , Pulmão/diagnóstico por imagem
10.
J Am Chem Soc ; 142(52): 21615-21621, 2020 12 30.
Artigo em Inglês | MEDLINE | ID: mdl-33326212

RESUMO

With the aid of bioorthogonal chemistry, we demonstrate the fabrication of synthetic dendrimers in situ around living cells. Using tetrazine dienophile and aminooxyl/hydrazide aldehyde chemistries, the density of functional groups on the dendrimers exponentially amplified intensities of fluorescent markers in antibody-targeted live cell imaging. This novel "swarming" approach highlights the power of bioorthogonal chemistry and provides a route to non-natural chemical structures on cells, paving the way for the generation of various artificial cellular nanostructures and scaffolds.

11.
Molecules ; 25(22)2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-33182751

RESUMO

Photodynamic inactivation of microorganisms has gained substantial attention due to its unique mode of action, in which pathogens are unable to generate resistance, and due to the fact that it can be applied in a minimally invasive manner. In photodynamic therapy (PDT), a non-toxic photosensitizer (PS) is activated by a specific wavelength of light and generates highly cytotoxic reactive oxygen species (ROS) such as superoxide (O2-, type-I mechanism) or singlet oxygen (1O2*, type-II mechanism). Although it offers many advantages over conventional treatment methods, ROS-mediated microbial killing is often faced with the issues of accessibility, poor selectivity and off-target damage. Thus, several strategies have been employed to develop target-specific antimicrobial PDT (aPDT). This includes conjugation of known PS building-blocks to either non-specific cationic moieties or target-specific antibiotics and antimicrobial peptides, or combining them with targeting nanomaterials. In this review, we summarise these general strategies and related challenges, and highlight recent developments in targeted aPDT.


Assuntos
Anti-Infecciosos/farmacologia , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/síntese química , Fármacos Fotossensibilizantes/farmacologia , Animais , Humanos , Concentração de Íons de Hidrogênio , Lipossomos/química , Camundongos , Micelas , Oligossacarídeos/química , Peptídeos/química , Polímeros/química , Oxigênio Singlete/química , Eletricidade Estática , Superóxidos
12.
Chem Commun (Camb) ; 56(89): 13856-13859, 2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33084632

RESUMO

A polymer scaffold, with multiple reactive centres, was synthesised by RAFT polymerisation and conjugated to the antibody herceptin. A hexahistidine RAFT agent enabled the rapid and simple purification of polymer-protein conjugates, while the tetrazine conjugation strategy allows myriad cargos to be attached and amplified.


Assuntos
Resinas Acrílicas/química , Corantes Fluorescentes/química , Histidina/química , Trastuzumab/química , Resinas Acrílicas/síntese química , Corantes Fluorescentes/síntese química , Estrutura Molecular , Norbornanos/química
13.
Sensors (Basel) ; 20(21)2020 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-33121191

RESUMO

Numerous optodes, with fluorophores as the chemical sensing element and optical fibres for light delivery and collection, have been fabricated for minimally invasive endoscopic measurements of key physiological parameters such as pH. These flexible miniaturised optodes have typically attempted to maximize signal-to-noise through the application of high concentrations of fluorophores. We show that high-density attachment of carboxyfluorescein onto silica microspheres, the sensing elements, results in fluorescence energy transfer, manifesting as reduced fluorescence intensity and lifetime in addition to spectral changes. We demonstrate that the change in fluorescence intensity of carboxyfluorescein with pH in this "high-density" regime is opposite to that normally observed, with complex variations in fluorescent lifetime across the emission spectra of coupled fluorophores. Improved understanding of such highly loaded sensor beads is important because it leads to large increases in photostability and will aid the development of compact fibre probes, suitable for clinical applications. The time-resolved spectral measurement techniques presented here can be further applied to similar studies of other optodes.

14.
Med Hypotheses ; 143: 110119, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32721811

RESUMO

Irritable bowel syndrome (IBS) is a common disorder worldwide, but the diagnosis is often overlooked. This study aimed to evaluate the sociodemographic characteristics of IBS patients and the relationship between IBS and fibromyalgia. 202 patients with gastrointestinal system complaints who were admitted to Sisli Hamidiye Etfal Trainnig and Research Hospital, Family Medicine Clinic were included in the study. P < 0.05 was considered statistically significant. Fibromyalgia was associated with IBS in 26.7% of the participants. There was a positive correlation between the incidence of fibromyalgia and use of medication due to IBS, change in stool frequency, generalized pain, frequent illness, headache, excessive stress cancer anxiety , workforce loss due to IBS symptoms and fibromyalgia (p < 0.05). The presence of generalized pain, among IBS symptoms, caused the most robust increase in the likelihood of fibromyalgia (80%). The symptoms which were increasing the possibility of fibromyalgia were mostly generalized pain, high WHOQOL total score, family history of cancer, and loss of workforce at admission. IBS is a condition that affects the daily life quality of individuals and is often a condition that can be confused or associated with other diseases. Primary care physicians should approach patients holistically, especially in patients with generalized pain, family history of cancer, loss of workforce at admission, and more careful about fibromyalgia in patients with high WHOQOL total score. This awareness will increase the chances of early diagnosis and treatment of patients and will provide less cost but more effective treatment.


Assuntos
Fibromialgia , Síndrome do Intestino Irritável , Detecção Precoce de Câncer , Fibromialgia/complicações , Fibromialgia/diagnóstico , Humanos , Síndrome do Intestino Irritável/complicações , Síndrome do Intestino Irritável/diagnóstico , Dor , Qualidade de Vida
16.
JCO Glob Oncol ; 6: 285-292, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32109157

RESUMO

PURPOSE: Breast cancer is the most frequent cancer in women, and there is a great variability in surgical practice for treating that cancer in different countries. The aims of this study were to analyze the effect of guidelines from the Turkish Federation of Breast Diseases Societies on academic institutions that have breast centers and to evaluate surgical practice in Turkey in 2018. PATIENTS AND METHODS: Between January and March 2019, a survey was sent to breast surgeons who were working in breast centers in academic institutions. The sampling frame included 24 academic institutions with breast centers in 18 cities in Turkey to evaluate interdisciplinary differences among breast centers and seven regions in Turkey regarding patients' choices, surgical approaches, and academic institutions. RESULTS: All surgeons responded to the survey, and all 4,381 patients were included. Most of the surgeons (73.9%) were working in a breast center. Multidisciplinary tumor boards were performed in 87% of the breast centers. The average time between clinical evaluation and initiation of treatment was 29 days; the longest time was in Southeast Anatolia (66 days). Only 6% of patients had ductal carcinoma in situ. Sentinel lymph node biopsy was available in every region across the country and was performed in 64.5% of the patients. In 2018, the overall breast-conserving surgery rate was 57.3% in Turkey, and it varied from 72.2% in the Black Sea region to 33.5% in Central Anatolia (P < .001). Oncoplastic breast surgery options were available at all breast centers. However, 25% of the breast centers from the Black Sea region and half the breast centers from Eastern Anatolia and the Mediterranean region did not perform this type of surgery. CONCLUSION: Increasing rates of nonpalpable breast cancer and decreasing rates of locoregional recurrences favored breast-conserving surgery, especially in developed countries. Guidelines from the Turkish Federation of Breast Diseases Societies resulted in more comprehensive breast centers and improved breast health in Turkey.


Assuntos
Neoplasias da Mama , Mastectomia Segmentar , Mar Negro , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/cirurgia , Feminino , Humanos , Recidiva Local de Neoplasia , Turquia/epidemiologia
17.
Eur Radiol ; 30(4): 2049-2057, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31822972

RESUMO

OBJECTIVES: Tumor-infiltrating lymphocytes (TILs) have been determined as a new prognostic indicator of immunotherapy response in breast cancer (BC). The aim of this study is to investigate the effectiveness of imaging features in predicting the TIL levels in invasive BC patients. METHODS: A total of 158 patients with invasive BC were included in our study. All lesions were evaluated based on the BIRADS lexicon. US was performed for all the patients and 89 of them underwent MRI. The histologic stromal TIL (sTIL) levels were assessed and associations between the sTIL levels and imaging features were evaluated. RESULTS: Tumors with high sTIL levels had more circumscribed margins, round shape, heterogeneous echogenicity, and larger size on ultrasonography (p < 0.005). There was a statistically significant positive correlation between the sTIL levels and ADC value (p < 0.001). Tumors with high sTIL levels had significantly more homogeneous enhancement than the tumors with low sTIL levels (p = 0.001). Logistic regression analysis showed that the ADC was the most statistically significant parameter in predicting the sTIL levels (the odds ratio was 90.952; p = 0.002). The optimal cutoff value for ADC in predicting low and high sTIL levels was found to be 0.87 × 10-3 mm2 s-1 (AUC = 0.726, 73% specificity, and 60% sensitivity). CONCLUSIONS: Imaging findings, especially the ADC, may play an important role as an adjunct tool in cases of uncertain situations and may improve the accuracy of biopsy results. The prediction of sTIL levels using imaging findings may give an opportunity to predict prognosis. KEY POINTS: • Preoperative assessment of TILs is an important biomarker of prognosis and treatment efficacy. • ADC value can be a useful tool in distinguishing high and low sTIL levels as a non-invasive method. • The prediction of sTIL levels using imaging findings may give an opportunity to predict prognosis and an optimal treatment for the BC patients.


Assuntos
Neoplasias da Mama/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Linfócitos do Interstício Tumoral/patologia , Ultrassonografia Mamária/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Progressão da Doença , Feminino , Humanos , Pessoa de Meia-Idade , Prognóstico
18.
Biomolecules ; 9(9)2019 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-31505877

RESUMO

In this study, we compared the levels of C-C chemokine receptor type 5 (CCR5), C-C motif chemokine ligand 5 (CCL5), platelet-derived growth factor (PDGF), and EphrinA7 (EphA7) in patients with colorectal carcinoma and healthy controls in order to investigate the significance and usability of these potential biomarkers in early diagnosis of colorectal cancer. The study included 70 colorectal carcinoma patients and 40 healthy individuals. The CCR5, CCL5, PDGF, and EphA7 levels were measured using ELISA in blood samples. PDGF-BB, EphA7, CCR5, and CCL5 levels of the patients with colorectal carcinoma were significantly higher compared to the control group (p < 0.001 for each comparison). Our logistic regression analysis (the area under the curve was 0.958) supports the notion that PDGF-BB, EphA7, and CCL5 are potential biomarkers for the diagnosis of colon cancer. The sensitivity, specificity, and positive and negative predictive values were found to be 87.9%, 87.5%, 92.1%, and 81.4%, respectively. To our knowledge, this is the first study that investigates the relationship between colorectal carcinoma and the four biomarkers CCL5, CCR5, PDGF, and EphA7. The significantly elevated levels of all these parameters in the patient group compared to the healthy controls indicate that they can be used for the early diagnosis of colorectal carcinoma.


Assuntos
Quimiocina CCL5/sangue , Neoplasias Colorretais/sangue , Neoplasias Colorretais/diagnóstico , Fator de Crescimento Derivado de Plaquetas/metabolismo , Receptor EphA7/sangue , Receptores CCR5/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Detecção Precoce de Câncer , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Adulto Jovem
19.
Eur J Breast Health ; 15(3): 158-162, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31312791

RESUMO

OBJECTIVE: The aim of this study is to investigate the effect of mini latissimus dorsi flap (MLDF) reconstruction on ipsilateral shoulder functions. MATERIALS AND METHODS: Those included in the study are the patients aged between 23 and 73, who were operated with the diagnosis of early breast cancer (cT1-3)N0). The first group includes the patients who had sentinel lymph node biopsy (SLNB) with partial mastectomy. The second group consists of the patients who had axillary lymph nodule dissection (ALND) with partial mastectomy. The third group includes the patients who had SLNB and MLDF with partial mastectomy. The fourth group includes the patients who had ALND and MLDF with partial mastectomy. Patients' Quick Disabilities of the Arm, Shoulder and Hand (Q-DASH) score work model point were recorded. RESULTS: 174 patients were included in this study. According to Q-DASH score, no functional change was detected in 69.5% of the patients, whereas slight functional loss was identified in 23.6%, moderate functional loss in 5.7%, severe functional loss 1.1%. In the comparison of Q-DASH scores in surgery groups, while these four groups were being analyzed, a significant difference was determined (p=0.007). When dual analyses were made, it was also established that the difference resulted from the group to which ALND and MLDF were applied together. CONCLUSION: We conclude that MLDF application for reconstruction purposes after breast surgery has a negative impact on shoulder functions of the patients who had both of partial mastectomy and ALND.

20.
Sci Rep ; 9(1): 7713, 2019 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-31118459

RESUMO

Physiological sensing deep in tissue remains a clinical challenge. Here a flexible miniaturised sensing optrode providing a platform to perform minimally invasive in vivo in situ measurements is reported. Silica microspheres covalently coupled with a high density of ratiometrically configured fluorophores were deposited into etched pits on the distal end of a 150 µm diameter multicore optical fibre. With this platform, photonic measurements of pH and oxygen concentration with high precision in the distal alveolar space of the lung are reported. We demonstrated the phenomenon that high-density deposition of carboxyfluorescein covalently coupled to silica microspheres shows an inverse shift in fluorescence in response to varying pH. This platform delivered fast and accurate measurements (±0.02 pH units and ±0.6 mg/L of oxygen), near instantaneous response time and a flexible architecture for addition of multiple sensors.


Assuntos
Tecnologia de Fibra Óptica/métodos , Fibras Ópticas , Alvéolos Pulmonares/diagnóstico por imagem , Animais , Broncoscopia , Feminino , Fluoresceínas/análise , Corantes Fluorescentes/análise , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura , Microesferas , Miniaturização , Oxigênio , Rodaminas/análise , Ovinos , Dióxido de Silício
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