Surface Decoration of Black Phosphorus Nanosheets to Generate Oxygen and Release 1O2 for Photodynamic Killing of Bacteria

AbstractA novel noninvasive photochemical approach for infection control, namely photodynamic therapy, has received much attention in the treatment of oral diseases which requires three nontoxic ingredients namely visible harmless light, a photosensitizer and oxygen are involved in this therapy. It is based on the principle that a photosensitizer binds to the target cells which when activated by light of a suitable wavelength results in the production of singlet oxygen and other very reactive agents that are extremely toxic to certain cells and bacteria. This article highlights the application of photo-dynamic therapy in management of periodontal disease and its current status.

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The effects of photodynamic therapy with Photodithazine on HPV 16 E6/E7 associated cervical cancer model

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s1088424611003082 ◽

2011 ◽

Vol 15 (03) ◽

pp. 174-180 ◽

Cited By ~ 4

Author(s):

Lan Ying Wen ◽

Su-Mi Bae ◽

Jin Hwan Do ◽

Kye-Shin Park ◽

Woong Shick Ahn

Keyword(s):

Cervical Cancer ◽

Photodynamic Therapy ◽

Growth Inhibition ◽

Biological Significance ◽

Light Irradiation ◽

Tumor Growth Inhibition ◽

Cancer Model ◽

Hpv 16

Photodynamic therapy (PDT) is a promising treatment for cancer that has been recently accepted in the clinic. In this study, we examined a biological significance of PDT with a chlorin-based photosensitizer, Photodithazine, on cervical cancer model. When human papillomavirus type 16 (HPV16)- transformed mouse TC-1 cells were exposed to varied doses of Photodithazine with light irradiation (6.25 J/cm2), the significant growth inhibition of TC-1 cells was observed at 0.75 μg/mL of Photodithazine. The damaged cells by Photodithazine/PDT were categorized to be early and late apoptosis, as determined by annexin V staining. Photodithazine was primarily localized at lysosome apparatus within TC-1 cells while it was rapidly accumulated and sustained for initial 3 h in tumor tissue of TC-1 tumor bearing mice after IV injection. The tumor growth inhibition by Photodithazine/PDT with light irradiation (300 J/cm2) was examined after injection of various concentration of Photodithazine in tumor mice system. Our results show that Photodithazine/PDT might have significant advantages in the selective killing of tumor lesions in HPV 16 E6/E7 associated cervical cancer model, both in vitro and in vivo.

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Photo-Induced Charge-Variable Conjugated Polyelectrolyte Brushes Encapsulating Upconversion Nanoparticles for Promoted siRNA Release and Collaborative Photodynamic Therapy under NIR Light Irradiation

Advanced Functional Materials ◽

10.1002/adfm.201702592 ◽

2017 ◽

Vol 27 (44) ◽

pp. 1702592 ◽

Cited By ~ 54

Author(s):

Hui Zhao ◽

Wenbo Hu ◽

Hengheng Ma ◽

Rongcui Jiang ◽

Yufu Tang ◽

...

Keyword(s):

Photodynamic Therapy ◽

Light Irradiation ◽

Upconversion Nanoparticles ◽

Conjugated Polyelectrolyte ◽

Polyelectrolyte Brushes ◽

Nir Light ◽

Induced Charge

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The Hypoxic Testicle: Physiology and Pathophysiology

Oxidative Medicine and Cellular Longevity ◽

10.1155/2012/929285 ◽

2012 ◽

Vol 2012 ◽

pp. 1-15 ◽

Cited By ~ 69

Author(s):

Juan G. Reyes ◽

Jorge G. Farias ◽

Sebastián Henríquez-Olavarrieta ◽

Eva Madrid ◽

Mario Parraga ◽

...

Keyword(s):

Germ Cell ◽

Testicular Torsion ◽

Oxygen Supply ◽

Cell Function ◽

Cell Damage ◽

The Body ◽

Body Core Temperature ◽

Seminiferous Tubules ◽

Low Oxygen ◽

Complex Biological Process

Mammalian spermatogenesis is a complex biological process occurring in the seminiferous tubules in the testis. This process represents a delicate balance between cell proliferation, differentiation, and apoptosis. In most mammals, the testicles are kept in the scrotum 2 to 7°C below body core temperature, and the spermatogenic process proceeds with a blood and oxygen supply that is fairly independent of changes in other vascular beds in the body. Despite this apparently well-controlled local environment, pathologies such as varicocele or testicular torsion and environmental exposure to low oxygen (hypoxia) can result in changes in blood flow, nutrients, and oxygen supply along with an increased local temperature that may induce adverse effects on Leydig cell function and spermatogenesis. These conditions may lead to male subfertility or infertility. Our literature analyses and our own results suggest that conditions such as germ cell apoptosis and DNA damage are common features in hypoxia and varicocele and testicular torsion. Furthermore, oxidative damage seems to be present in these conditions during the initiation stages of germ cell damage and apoptosis. Other mechanisms like membrane-bound metalloproteinases and phospholipase A2 activation could also be part of the pathophysiological consequences of testicular hypoxia.

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Applications of Oxygen-Carrying Micro/Nanobubbles: a Potential Approach to Enhance Photodynamic Therapy and Photoacoustic Imaging

10.20944/preprints201808.0210.v1 ◽

2018 ◽

Author(s):

M. Saad Khan ◽

Jangsun Hwang ◽

Kyungwoo Lee ◽

Yonghyun Choi ◽

Kyobum Kim ◽

...

Keyword(s):

Photodynamic Therapy ◽

Oxygen Supply ◽

Photoacoustic Imaging ◽

Supply And Demand ◽

Flexible Structures ◽

Synthesis Methods ◽

Oxygen Species ◽

Hypoxic Conditions ◽

Potential Use ◽

Resistance To Chemotherapy

Microbubbles and nanobubbles can be prepared using various shells, such as phospholipids, polymers, proteins, and surfactants. They are echogenic and can be used as contrast agents for ultrasonic and photoacoustic imaging. These bubbles can be engineered in various sizes as vehicles for gas and drug delivery applications with novel properties and flexible structures. Hypoxic areas in tumors develop owing to an imbalance of oxygen supply and demand. In tumors, hypoxic regions have shown more resistance to chemotherapy, radiotherapy, and photodynamic therapies. The efficacy of photodynamic therapy depends on the availability of oxygen in the tumor to generate reactive oxygen species. Micro/nanobubbles have been shown to reverse hypoxic conditions and increase tissue oxygen levels. This review summarizes the synthesis methods and shell compositions of micro/nanobubbles and methods deployed for oxygen delivery. In addition, the shortcomings and prospects of engineering micro/nanobubbles are discussed for their potential use in photodynamic therapy.

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The effects of oxygen and medicines on T cells in hypoxic co-culture

10.22514/sv.2021.103 ◽

2021 ◽

Keyword(s):

T Cells ◽

Cell Viability ◽

Oxygen Supply ◽

Interleukin 2 ◽

Hypoxic Condition ◽

Severe Trauma ◽

Multiple Organ ◽

Trauma Patients ◽

Low Oxygen ◽

Western Blots

Objectives: Many patients with massive hemorrhage, respiratory failure due to trauma admit the emergency department, and further that the experience can fall into shock, inducing to sepsis, multiple organ failure due to hyperinflammation or immunosuppression. In the these patients, the low oxygen flow with immunosuppression is believed to play a significant role. Hence, oxygen supply and medicines is essential in severe trauma patients. Therefore, this study aims to investigate the effects of oxygen and variable medicines in hypoxic condition. Methods: T cells and macrophages were plated into trans-well plate for co-culture for 30 minutes in hypoxia. After that, the cells were stimulated with lipopolysaccharide (LPS) followed by variable medicines by normoxia or oxygen supply for 2 hrs and cells were inculated overnight under normoxic conditions. The T cell viability was measured by MTT, and the expression of interleukin-2 (IL-2), interleukin-8 (IL-8) and macrophage migration inhibitory factor (MIF) were measured by western blots using the T cells with co-culture with inflammatory maccrophages. Also, the concentration of MIF was analyzed by ELISA. Results: The T cells viability was decreased in hypoxia with LPS stimulation, however, pentoxifylline (PTX) effectively restored cell viability regardless of oxygen state (p < 0.05). Besides, PTX in oxygen supply status restored the decreases in IL-2 expression of T cells and the increases MIF in the LPS stimulation with hypoxia (p < 0.05). Conclusions: PTX has more effectively restored the T cells immunosuppression in hypoxia during oxygen supply, and has an immunomodulation effect by controlling hyperinflammation.

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