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1.
Chem Commun (Camb) ; 56(83): 12562-12565, 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-32940286

RESUMO

Near-infrared (NIR) light control of living cellular activities is a highly desired technique for living cell manipulation because of its advantage of high penetrability towards living tissue. In this study, (π-extended porphyrin)-fullerene linked molecules are designed and synthesized to achieve NIR light control of the membrane potential. A donor-(π-extended porphyrin)-acceptor linked molecule exhibited the formation of the charge-separated state with a relatively long lifetime (0.68 µs) and a moderate quantum yield (27-31%). The hydrophilic trimethylammonium-linked triad molecule successfully altered PC12 cells' membrane potential via photoinduced intramolecular charge separation.

3.
Nanoscale ; 12(43): 22049-22058, 2020 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-32895675

RESUMO

The increased production of semiconductor nanomaterials such as heavy metal quantum dots and perovskites for applications such as in energy harvesting, optoelectronic devices, bioanalysis, phototherapy and consumer health products raises concerns regarding nanotoxicity. After disposal, these materials degrade upon interaction with the environment, such as rain and surface waters, soil and oxygen, and solar irradiation, leading to the release of heavy metal ions in the environment with exposure to aquatic and terrestrial animals and plants, and humans. Researchers are in the early stages of understanding the potential toxicity of such nanomaterials by quantifying the amount of heavy metal ions released due to environmental or biological transformation. Here, we evaluate the toxicity of environmentally transformed nanomaterials by considering PbS quantum dots as a model system. Using metal ion sensors and steady-state fluorescence spectroscopy, we quantify the amount of Pb2+ released by the photochemical etching of quantum dots. Furthermore, with the help of cytotoxicity and comet assays, and DNA gel electrophoresis, we evaluate the adverse effects of the released metal ions into the cultured lung epithelial (H1650), and neuronal (PC12) cells. These studies reveal higher levels of cell proliferation and DNA damage to PC12 cells, suggesting the neurotoxicity of lead due to not only the downregulation of glutathione, elevated levels of reactive oxygen and nitrogen species, and a calcium influx but also the proactivation of activator protein 1 that is correlated with protein kinase c. This research shows the significance of molecular biology studies on different cells and animals to critically understand the health and environmental costs of heavy metal-based engineered nanomaterials.

4.
Chem Commun (Camb) ; 56(45): 6153, 2020 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-32458898

RESUMO

Correction for 'The optimization of cancer photodynamic therapy by utilization of a pi-extended porphyrin-type photosensitizer in combination with MITO-Porter' by Satrialdi et al., Chem. Commun., 2020, 56, 1145-1148, DOI: 10.1039/C9CC08563G.

5.
Anticancer Res ; 40(1): 81-86, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31892555

RESUMO

BACKGROUND/AIM: Zinc finger protein ZKSCAN3 (ZNF306) is a promising oncogene candidate in colon, bladder, breast, uterine cervical, and prostate cancers. The present study aimed to investigate ZKSCAN3 protein expression in gastric carcinoma patient tissues and to evaluate oncological outcomes in these patients. MATERIALS AND METHODS: ZKSCAN3 was detected using the anti-ZKSCAN3 rabbit polyclonal antibody. For immunohistochemical examination, we used paraffin-embedded specimens from 87 consecutive patients with gastric cancer who underwent gastrectomy. We investigated ZKSCAN3 expression in relation with patient prognosis and clinicopathological factors. RESULTS: ZKSCAN3 was detected in 28 (32.2%) tumour specimens, with significant association with lymphatic system invasion and distant metastasis. Patients with ZKSCAN3-positive tumours had worse overall survival (OS) than those with ZKSCAN3-negative tumours based on log-rank testing. Furthermore, multivariate analysis revealed that ZKSCAN3 was an independent prognostic parameter for OS (hazard ratio: 2.6379, p=0.0164). CONCLUSION: ZKSCAN3 is a potential novel prognostic factor in gastric cancer patients.


Assuntos
Biomarcadores Tumorais , Neoplasias Gástricas/genética , Neoplasias Gástricas/mortalidade , Fatores de Transcrição/genética , Idoso , Idoso de 80 Anos ou mais , Linhagem Celular Tumoral , Feminino , Expressão Gênica , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Metástase Neoplásica , Estadiamento de Neoplasias , Prognóstico , Modelos de Riscos Proporcionais , Recidiva , Fatores de Risco , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/metabolismo
6.
Chem Commun (Camb) ; 56(7): 1145-1148, 2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31895356

RESUMO

The uncontrolled production of reactive oxygen species during photodynamic therapy (PDT) induces oxidative stress. The full potential of PDT is accomplished by delivery of a pi-extended porphyrin-type photosensitizer into mitochondria of tumor cells using a MITO-Porter, a mitochondrial targeting nanodevice. This strategy can be implemented for innovative cancer therapy.

7.
Biomolecules ; 10(1)2020 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-31948035

RESUMO

There have been many reports on the relationship between mitochondrial oxidative stress and various types of diseases. This review covers mitochondrial targeting photodynamic therapy and photothermal therapy as a therapeutic strategy for inducing mitochondrial oxidative stress. We also discuss other mitochondrial targeting phototherapeutic methods. In addition, we discuss anti-oxidant therapy by a mitochondrial drug delivery system (DDS) as a therapeutic strategy for suppressing oxidative stress. We also describe cell therapy for reducing oxidative stress in mitochondria. Finally, we discuss the possibilities and problems associated with clinical applications of mitochondrial DDS to regulate mitochondrial oxidative stress.

8.
Chemistry ; 26(10): 2133-2137, 2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-31750582

RESUMO

Repeated absorption of emitted photons, also called photon recycling, in large crystals and thick films of perovskites leads to delayed photoluminescence (PL) and decrease of PL intensity. The role of distinct band gaps, which act as donors and acceptors of energy, and nonradiative energy transfer on such delayed, low intensity emission is yet to be rationalized. Here we report delayed emission by nonradiative energy transfer across a distribution of energy states in close-packed crystallites of cesium lead bromide CsPbBr3 , formamidinium lead bromide FAPbBr3 , or the mixed halide FAPb(BrI)3 perovskite synthesized in the form of thick pellets by the piezochemical method. The PL lifetime of the bromide-rich domain in the mixed halide pellet is considerably decreased when compared with a pure FAPbBr3 pellet. Here the domains with higher bromide composition act as the energy donor, whereas the iodide-rich domains are the acceptors. Time-resolved PL measurements of CsPbBr3 , FAPbBr3 , and the mixed halide FAPb(BrI)3 perovskite pellets help us to clarify the role of nonradiative energy transfer on photon recycling.

9.
Chemistry ; 26(9): 2060-2066, 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-31837054

RESUMO

The conversion of solar energy to thermal, chemical, or electrical energy attracts great attention in chemistry and physics. There has been a considerable effort for the efficient extraction of photons throughout the entire solar spectrum. In this work light energy was efficiently harvested by using a long-lived betaine photogenerated from an acridinium-based electron donor-acceptor dyad. The photothermal energy-conversion efficiency of the dyad is significantly enhanced by simultaneous illumination with blue (420-440 nm) and yellow (>480 nm) light in comparison with the sum of the conversion efficiencies for individual illumination with blue or yellow light. The enhanced photothermal effect is due to the photogenerated betaine, which absorbs longer-wavelength light than the dyad, and thus the dyad-betaine combination is promising for efficient photothermal energy conversion. The mechanisms of betaine generation and energy conversion are discussed on the basis of steady-state and transient spectral measurements.

10.
Chem Sci ; 10(27): 6642-6650, 2019 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-31367317

RESUMO

As structure defined cutouts of the graphene lattice, nanographene molecules have gained plenty of attention because of their high potential for versatile applications in organic electronics and energy conversion devices and as ideal model systems for the better understanding of intrinsic structure-property correlations of graphenes. In this study, well-defined nanographenes with sp2 carbon networks of different sizes, hexa-peri-hexabenzocoronene (HBC) and its rectangularly π-extended version, a short graphene nanoribbon (GNR), have been covalently functionalized with photoactive porphyrin molecules. On the basis of their spectroscopic studies, the photodynamics of the porphyrin-linked nanographenes was found to be influenced substantially by the size of the nanographenes. Photoexcitation of the porphyrin-HBC linked system led to exclusive energy transfer (EnT) from the first singlet excited state (S1) of the nanographene to the porphyrin, whereas opposite selective EnT occurred from the first and second singlet excited states (S1 and S2) of the porphyrin to the nanographene in the porphyrin-GNR linked system. In particular, ultrafast efficient EnTs from both the S2 and S1 states of the porphyrin to GNR mimic the corresponding ultrafast EnTs from the S2 and S1 states of carotenoids to chlorophylls in light-harvesting systems of natural photosynthesis. Such unique photophysical properties will be useful for the rational design of carbon-based photofunctional nanomaterials for optoelectronics and solar energy conversion devices.

11.
Int J Biol Sci ; 15(7): 1546-1556, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31337983

RESUMO

Intermediate filaments play significant roles in governing cell stiffness and invasive ability. Nestin is a type VI intermediate filament protein that is highly expressed in several high-metastatic cancer cells. Although inhibition of nestin expression was shown to reduce the metastatic capacity of tumor cells, the relationship between this protein and the mechanism of cancer cell metastasis remains unclear. Here, we show that nestin softens the cell body of the highly metastatic mouse breast cancer cell line FP10SC2, thereby enhancing the metastasis capacity. Proximity ligation assay demonstrated increased binding between actin and vimentin in nestin knockout cells. Because nestin copolymerizes with vimentin and nestin has an extremely long tail domain in its C-terminal region, we hypothesized that the tail domain functions as a steric inhibitor of the vimentin-actin interaction and suppresses association of vimentin filaments with the cortical actin cytoskeleton, leading to reduced cell stiffness. To demonstrate this function, we mechanically pulled vimentin filaments in living cells using a nanoneedle modified with vimentin-specific antibodies under manipulation by atomic force microscopy (AFM). The tensile test revealed that mobility of vimentin filaments was increased by nestin expression in FP10SC2 cells.


Assuntos
Actinas/química , Metástase Neoplásica/patologia , Nestina/fisiologia , Vimentina/química , Animais , Sistemas CRISPR-Cas , Linhagem Celular Tumoral , Quimiotaxia , Citoesqueleto/química , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Microscopia de Força Atômica , Invasividade Neoplásica , Nestina/química , Domínios Proteicos , Análise de Sequência de RNA , Estresse Mecânico
12.
Surg Radiol Anat ; 41(11): 1351-1359, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31297560

RESUMO

PURPOSE: This study aimed to morphologically and histologically investigate the relationship between deep subregions of the rotator cuff muscle and shoulder joint capsule as well as the relationship between the rotator cuff tendon or capsule and bony insertion. METHODS: We examined 13 shoulders of embalmed cadavers and measured the capsular attachments and footprints macroscopically. We also histologically examined the fibres in three shoulders. RESULTS: Loose attachment, which was less tight with spaced connective tissue, and firm attachment, which was tight with dense connective tissue, were found under the surface of the supraspinatus and infraspinatus. The anterior-deep and posterior-deep subregions of the supraspinatus and the middle partition and inferior partition of the infraspinatus formed firm attachments to the capsule. The mean areas of firm attachment for the anterior-deep subregion, posterior-deep subregion and middle partition were 118.8 mm2, 267.8 mm2 and 399.3 mm2, respectively, while the area of the inferior partition was small. The transverse fibres were located just lateral to the medial edge of the firm attachment area. The thick capsule had a substantial footprint. Both tendon fibres and the capsule inserted into the superior and middle facets through the attachment fibrocartilage. CONCLUSIONS: The posterior-deep subregion of the supraspinatus and middle partition of the infraspinatus evenly occupied the capsular attachment area. The transverse fibres were located just lateral to the medial edge of the firm attachment area, and the thick capsule had a substantial footprint. Both tendon fibres and the capsule inserted into the superior and middle facets through the attachment fibrocartilage.


Assuntos
Manguito Rotador/anatomia & histologia , Articulação do Ombro/anatomia & histologia , Ombro/anatomia & histologia , Idoso de 80 Anos ou mais , Cadáver , Cartilagem Articular/anatomia & histologia , Feminino , Humanos , Masculino
13.
Int. j. morphol ; 36(3): 859-863, Sept. 2018. graf
Artigo em Inglês | LILACS | ID: biblio-954198

RESUMO

The articularis genus, which lies under the vastus intermedius, has been regarded as part of the quadriceps femoris. However, they are well known to have different function because their respective origins and insertions are mutually distinct. These muscles are considered to work almost simultaneously when the knee is extended. The electromyogram has been used to demonstrate muscle co-contraction. However, the articularis genus is deeper than other muscles. Moreover, it is difficult to analyze it by surface electromyogram. The relative proportions of muscle fiber types and the characteristics of these fiber types are important determinants of the surface electromyogram. Furthermore, biomechanical analysis of AG has remained unclear. This study investigated the ratio of muscle fiber types in these muscles. Muscle samples from seven human cadaveric specimens were used with application of immunofluorescence double staining. Results show that in the vastus intermedius and articularis genus, the percentage of Type I fibers was significantly higher than that of Type II fibers. No significant difference was found in the mean percentages of Type I and Type II fiber types. The percentages of Type I and Type II fibers in articularis genus muscle were correlated positively to the percentage in the vastus intermedius. These results suggest that similar muscle fiber compositions of these muscles might reflect their contraction during the same active phase of knee extension, despite their different functions.


El músculo articular de la rodilla, que se encuentra cubierto por el músculo vasto intermedio, se ha considerado como parte del músculo cuádriceps femoral. Sin embargo, es sabido que tienen diferentes funciones debido a que sus respectivos orígenes e inserciones son mutuamente distintas. Se considera que estos músculos trabajan de forma casi simultánea cuando la rodilla está extendida. El electromiograma se ha usado para demostrar la contracción muscular. Sin embargo, el músculo articular de la rodillas es más profundo que otros músculos. Además, es difícil analizarlo por electromiograma de superficie. Las proporciones relativas de los tipos de fibras musculares y las características de estos tipos de fibras son importantes determinantes del electromiograma de superficie. Además, el análisis biomecánico de músculo articular de la rodilla no ha sido claro. Este estudio investigó la proporción de tipos de fibras musculares en estos músculos. Se usaron muestras musculares de siete cadáveres humanos con la aplicación de doble tinción de inmunofluorescencia. Los resultados muestran que en los músculos articular de la rodilla y vasto intermedio, el porcentaje de fibras de Tipo I fue significativamente mayor que el de las fibras de Tipo II. No se encontraron diferencias significativas en los porcentajes medios de los Tipo I y Tipo II. Los porcentajes de fibras Tipo I y Tipo II en el músculo articular de la rodilla se correlacionaron positivamente con el porcentaje en el músculo vasto intermediario. Estos resultados sugieren que las composiciones de las fibras musculares similares de estos músculos podrían reflejar su contracción durante la misma fase activa de la extensión de la rodilla, a pesar de sus diferentes funciones.


Assuntos
Humanos , Masculino , Feminino , Idoso , Idoso de 80 Anos ou mais , Músculo Esquelético/anatomia & histologia , Fibras Musculares Esqueléticas , Joelho/anatomia & histologia , Cadáver , Imunofluorescência , Músculo Quadríceps/anatomia & histologia
14.
ACS Nano ; 12(9): 9060-9069, 2018 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-30103604

RESUMO

Semiconductor quantum dots with stable photoluminescence are necessary for next generation optoelectronic and photovoltaic devices. Photoluminescence intensity fluctuations of cadmium and lead chalcogenide quantum dots have been extensively investigated since the first observation of blinking in CdSe nanocrystals in 1996. In a quantum dot, blinking originates from stochastic photocharging, nonradiative Auger recombination, and delayed neutralization. So far, blinking is suppressed by defect passivation, electron transfer, and shell preparation, but without any deep insight into free energy change of electron transfer. We report real-time detection of significant blinking suppression for CdSe/ZnS quantum dots exposed to N, N-dimethylaniline, which is accompanied by a considerable increase in the time-averaged photoluminescence intensity of quantum dots. Although the Gibbs (free) energy change (Δ Get = +2.24 eV), which is estimated electrochemically and from density functional theory calculations, is unfavorable for electron transfer from N, N-dimethylaniline to a quantum dot in the minimally excited (band-edge) state, electron transfer is obvious when a quantum dot is highly excited. Nonetheless, Δ Get crosses from the positive to negative scale as the solvent dielectric constant exceeds 5, favoring electron transfer from N, N-dimethylaniline to a quantum dot excited to the band-edge state. Based on single-molecule photoluminescence and ensemble electron transfer studies, we assign blinking suppression to the transfer of an electron from N, N-dimethylaniline to the hot hole state of a quantum dot. In addition to blinking suppression by electron transfer, complete removal of blinking is limited by short-living OFF states induced by the negative trion.

15.
Clin Interv Aging ; 13: 1011-1017, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29872279

RESUMO

Purpose: Fat infiltration (FI) in the gluteus minimus muscle (GMin) has been reported as being restricted to the anterior part. The aim of this study was to verify whether FI is localized only to the anterior part of the GMin through the dissection of large number of elderly cadavers and to clarify the underlying mechanism of FI localized to a specific region. Materials and methods: Thirty-eight hips from 20 embalmed elder cadavers were dissected for verification of FI localization. The samples of three regions - the fat infiltrated region of the anterior part (FI), the region without FI (non-FI), and the posterior region - were harvested from nine hips for the histological fiber type assessment. Results: The FI area was distributed at 2.6°-38° from the anterior border within the anterior part, of which function is responsible for hip extension and internal rotation and is likely reduced by disuse following aging. The number of type I fibers was lowest in FI, followed by non-FI, while the number of type I fibers was highest in the posterior. Meanwhile, the number of type II fibers was equivalent across the three regions. Atrophic type II fibers were observed in overall samples of the three regions, and grouped atrophy, which is evidence of denervation, was observed in FI and non-FI samples. Type grouping, which suggests to be reinnervated, was found in the non-FI and posterior samples but very little in the FI samples. Conclusion: FI in the GMin in older adults restricted to deep within the anterior part is secondary to disuse and is strongly related to impaired denervation-reinnervation process.


Assuntos
Tecido Adiposo/fisiologia , Músculo Esquelético/fisiologia , Coxa da Perna/fisiologia , Tecido Adiposo/anatomia & histologia , Idoso , Dorso/fisiologia , Nádegas , Cadáver , Feminino , Humanos , Masculino , Músculo Esquelético/anatomia & histologia , Coxa da Perna/anormalidades
16.
Nanoscale ; 10(28): 13368-13374, 2018 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-29790552

RESUMO

The broad absorption of light in the UV-Vis-NIR region and the size-based tunable photoluminescence color of semiconductor quantum dots make these tiny crystals one of the most attractive antennae in solar cells and phosphors in electrooptical devices. One of the primary requirements for such real-world applications of quantum dots is their stable and uniform distribution in optically transparent matrices. In this work, we prepare transparent thin films of polymer-quantum dot conjugates, where CdSe/ZnS quantum dots are uniformly distributed at high densities in a chitosan-polystyrene copolymer (CS-g-PS) matrix. Here, quantum dots in an aqueous solution are conjugated to the copolymer by a phase transfer reaction. With the stable conjugation of quantum dots to the copolymer, we prevent undesired phase separation between the two and aggregation of quantum dots. Furthermore, the conjugate allows us to prepare transparent thin films in which quantum dots are uniformly distributed at high densities. The CS-g-PS copolymer helps us in not only preserving the photoluminescence properties of quantum dots in the film but also rendering excellent photostability to quantum dots at the ensemble and single particle levels, making the conjugate a promising material for photoluminescence-based devices.

17.
World J Surg ; 42(3): 766-772, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28920152

RESUMO

BACKGROUND AND PURPOSE: We started performing sentinel node navigation surgery (SNNS) for patients with early gastric cancer (EGC) using infrared ray electronic endoscopy (IREE) with indocyanine green injection from year 2000. The EGCs usually have complex lymphatic drainage, unidirectional or multidirectional lymphatic flow. In this study, we investigated and clarified factors that affect the direction of gastric lymphatic drainage. PATIENTS AND METHOD: Consecutive 60 patients with EGC who underwent SNNS by IREE from year 2006 to 2014 were enrolled to this study. Patients' age, gender, location of tumors, operative method, previous treatment by endoscopic submucosal dissection (ESD), presence of pathological ulcerative scar and maximum tumor diameter were enrolled as parameters which may affect direction of lymphatic drainage and analyzed. RESULT: Bivariate analysis demonstrated that the presence of pathological ulcerative scar (P = 0.01), tumor location (g.c vs. a.w vs. p.w vs. l.c, P = 0.01), and maxim tumor diameter (P = 0.0003) were relevant to direction of gastric lymphatic drainage. Multivariate analysis showed that tumor location (g.c/a.w/p.w vs. l.c, odds ratio 8.227, P = 0.011) and the maximum tumor diameter (odds ratio 1.057, P = 0.037) are independent factors that affect direction of gastric lymphatic flow. Of tumors, 78% located at lesser curvature had unidirectional lymphatic drainage, and 93% of tumors whose diameter was 40 mm and more had multidirectional lymphatic drainage. CONCLUSION: Our investigation revealed that the tumor location and tumor diameter were the key factors which affect the direction of lymphatic drainage, which is useful fact to understand the complexity of gastric lymphatic drainage.


Assuntos
Vasos Linfáticos/anatomia & histologia , Biópsia de Linfonodo Sentinela , Neoplasias Gástricas/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Feminino , Gastroscopia/métodos , Humanos , Verde de Indocianina , Raios Infravermelhos , Excisão de Linfonodo/métodos , Metástase Linfática , Vasos Linfáticos/fisiopatologia , Masculino , Pessoa de Meia-Idade , Neoplasias Gástricas/patologia
18.
Nanoscale ; 9(47): 18690-18698, 2017 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-29165486

RESUMO

It has been known for decades that intracellular redox reactions control various vital functions in living systems, which include the synthesis of biomolecules, the modulation of protein functions, and cell signaling. Although there have been several reports on the control of such functions using DNA and RNA, the non-invasive optical control of biological functions is an important ongoing challenge. In this study, a hybrid of an electron donor-acceptor linked molecule based on a ferrocene(Fc)-porphyrin(ZnP)-fullerene(C60) analogue and an elaborately designed nano-carrier, referred to herein as a MITO-Porter, resulted in a successful photoinduced intermolecular electron transfer reaction via the long-lived intramolecular charge separation, leading to site-specific reductive reactions in the mitochondria of living HeLa cells. A Fc-ZnP-C60 linked molecule, 1-Oct, was designed and prepared for taking advantage of the unique photophysical properties with excellent efficiency (i.e. a long lifetime and a high quantum yield) for photoinduced charge separation. The targeted delivery of 1-Oct to mitochondria was accomplished by using a combination of the Fc-ZnP-C60 molecule and a drug delivery nano-carrier, MITO-Porter, that was recently established by our group for intracellular cargo delivery. The successful delivery of 1-Oct by the MITO-Porter permitted the optically-controlled generation of O2- in the mitochondria of HeLa cells and the following induction of apoptosis as a cell signalling response was observed in confocal laser microscopy experiments. The obtained results indicate the use of an electron donor-acceptor system such as this can be a promising tool for the non-invasive triggering of redox-coupled cellular activities in living systems.

19.
Nanoscale ; 9(45): 17909-17913, 2017 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-29124263

RESUMO

Donor-acceptor-linked molecules have been synthesized and utilized to induce the rapid and site-selective lipid-oxidation in mitochondria by utilizing a photoinduced intermolecular electron transfer reaction. Two water-soluble donor-acceptor molecules (1 and 2) were designed and synthesized for this purpose. 2 was prepared to modulate its affinity to cell membrane in mitochondria. Confocal laser microscopy experiments revealed that 1 and 2 possess high localization abilities in mitochondria. By the photoinduced electron transfer, 2 exhibited the remarkable oxidation ability of lipids, mainly cardiolipin. In HeLa cells, 2 triggered mitochondrial lipid oxidation, which was followed by apoptotic cell death, under illumination within a few seconds. These results show that the present molecular system is highly promising to utilize the photoinduced intermolecular electron transfer reaction in a precise spatiotemporal manner in a cell by using light.

20.
Chemistry ; 22(50): 18115-18122, 2016 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-27791293

RESUMO

We report that Ce@C2v (9)-C82 forms a centrosymmetric dimer when co-crystallized with Ni(OEP) (OEP = octaethylporphyrin dianion). The crystal structure of {Ce@C2v (9)-C82 }2 ⋅2[Ni(OEP)]⋅4 C6 H6 shows that a new C-C bond with a bond length of 1.605(5) Šconnects the two cages. The high spin density of the singly occupied molecular orbital (SOMO) on the cage and the pyramidalization of the cage are factors that favor dimerization. In contrast, the treatment of Ni(OEP) with M@C2v (9)-C82 (M = La, Sc, and Y) results in crystallization of monomeric endohedral fullerenes. A systematic comparison of the X-ray structures of M@C2v (9)-C82 (M = Sc, Y, La, Ce, Gd, Yb, and Sm) reveals that the major metal site in each case is located at an off-center position adjacent to a hexagonal ring along the C2  axis of the C2v (9)-C82 cage. DFT calculations at the M06-2X level revealed that the positions of the metal centers in these metallofullerenes M@C2v (9)-C82 (M = Sc, Y, and Ce), as determined by single-crystal X-ray structure studies, correspond to an energy minimum for each compound.

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