scholarly journals Functionalized nanomaterials: their use as contrast agents in bioimaging: mono- and multimodal approaches

2013 ◽  
Vol 2 (2) ◽  
pp. 125-169 ◽  
Author(s):  
Quentin Le Trequesser ◽  
Hervé Seznec ◽  
Marie-Hélène Delville
Keyword(s):  
Contrast Agents ◽  
Photoacoustic Imaging ◽  
Imaging Techniques ◽  
Ion Beam ◽  
Medical Diagnostics ◽  
Molecular Probes ◽  
The Body ◽  
Wide Range

AbstractThe successful development of nanomaterials illustrates the considerable interest in the development of new molecular probes for medical diagnosis and imaging. Substantial progress was made in the synthesis protocol and characterization of these materials, whereas toxicological issues are sometimes incomplete. Nanoparticle-based contrast agents (CAs) tend to become efficient tools for enhancing medical diagnostics and surgery for a wide range of imaging modalities. The multimodal nanoparticles (NPs) are much more efficient than the conventional molecular-scale CAs. They provide new abilities for in vivo detection and enhanced targeting efficiencies through longer circulation times, designed clearance pathways, and multiple binding capacities. Properly protected, they can safely be used for the fabrication of various functional systems with targeting properties, reduced toxicity, and proper removal from the body. This review mainly describes the advances in the development of mono- to multimodal NPs and their in vitro and in vivo relevant biomedical applications ranging from imaging and tracking to cancer treatment. Besides the specific applications for classical imaging (magnetic resonance imaging, positron emission tomography, computed tomography, ultrasound, and photoacoustic imaging), the less common imaging techniques such as terahertz molecular imaging (THMI) or ion beam analysis (IBA) are mentioned. The perspectives on the multimodal theranostic NPs and their potential for clinical advances are also mentioned.

Challenges on the effect of cell phone radiation on mammalian embryos and fetuses: a review of the literature

Zygote ◽  
2021 ◽  
pp. 1-7
Author(s):  
Maryam Mahaldashtian ◽  
Mohammad Ali Khalili ◽  
Fatemeh Anbari ◽  
Mohammad Seify ◽  
Manuel Belli
Keyword(s):  
Embryo Development ◽  
Animal Studies ◽  
Cell Phones ◽  
Cellular Phone ◽  
The Body ◽  
Human Embryos ◽  
Success Rates ◽  
Wide Range

Summary Cell phones operate with a wide range of frequency bands and emit radiofrequency-electromagnetic radiation (RF-EMR). Concern on the possible health hazards of RF-EMR has been growing in many countries because these RF-EMR pulses may be absorbed into the body cells, directly affecting them. There are some in vitro and in vivo animal studies related to the consequences of RF-EMR exposure from cell phones on embryo development and offspring. In addition, some studies have revealed that RF-EMR from cellular phone may lead to decrease in the rates of fertilization and embryo development, as well as the risk of the developmental anomalies, other studies have reported that it does not interfere with in vitro fertilization or intracytoplasmic sperm injection success rates, or the chromosomal aberration rate. Of course, it is unethical to study the effect of waves generated from cell phones on the forming human embryos. Conversely, other mammals have many similarities to humans in terms of anatomy, physiology and genetics. Therefore, in this review we focused on the existing literature evaluating the potential effects of RF-EMR on mammalian embryonic and fetal development.

scholarly journals Glutamine: Metabolism and Immune Function, Supplementation and Clinical Translation

2018 ◽  
Author(s):  
Vinicius Cruzat ◽  
Marcelo Macedo Rogero ◽  
Kevin Noel Keane ◽  
Rui Curi ◽  
Philip Newsholme
Keyword(s):  
Amino Acid ◽  
The Body ◽  
Glutamine Metabolism ◽  
In Vivo Studies ◽  
Glutamine Supplementation ◽  
Bacterial Killing ◽  
Nutrition Supplementation ◽  
Wide Range

Glutamine is the most abundant and versatile amino acid in the body. In health and disease, the rate of glutamine consumption by immune cells is similar or greater than glucose. For instance, in vitro and in vivo studies have determined that glutamine is an essential nutrient for lymphocyte proliferation and cytokine production, macrophage phagocytic plus secretory activities and neutrophil bacterial killing. Glutamine release to the circulation and availability is mainly controlled by key metabolic organs, such as the gut, liver and skeletal muscles. During catabolic/hypercatabolic situations glutamine can become essential for metabolic function, but its availability may be compromised due to impairment of homeostasis in the inter-tissue metabolism of amino acids. For this reason, glutamine is currently part of clinical nutrition supplementation protocols and/or recommended for immune suppressed individuals. However, in a wide range of catabolic/hypercatabolic situations (e.g. ill/critically ill, post-trauma, sepsis, exhausted athletes) it is currently difficult to determine whether glutamine parenteral or enteral supplementation should be recommended based on the amino acid plasma concentration (glutaminemia). Although the beneficial immune based effects of glutamine supplementation is already established, many questions and evidence for positive in vivo outcomes still remain to be presented. Therefore, this paper provides an integrated review on how glutamine metabolism in key organs is important to cells of the immune system. We also discuss glutamine metabolism, action and important issues related to the effects of glutamine supplementation in catabolic situations.

scholarly journals Organic nanoparticle-doped microdroplets as dual-modality contrast agents for ultrasound microvascular flow and photoacoustic imaging

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Yu Xu ◽  
Guoyun Sun ◽  
Eshu Middha ◽  
Yu-Hang Liu ◽  
Kim Chuan Chan ◽  
...  
Keyword(s):  
Blood Flow ◽  
Nude Mice ◽  
Photoacoustic Imaging ◽  
Imaging Techniques ◽  
Contrast Effects ◽  
In Vivo Evaluation ◽  
Dual Modality ◽  
In Vivo Experiments

Abstract Tumor blood vessels are chaotic and abundantly distributed, owing to their heterogeneity. Therefore, imaging techniques which reveal abnormalities of tumor vasculature play significant roles in both mechanistic and clinical diagnostic tumor studies. Photoacoustic (PA) imaging uses the intrinsic characteristics of hemoglobin, to acquire tumor hemodynamic information, while ultrasound (US) imaging provides information about tumoral vessel structures and blood flow. To improve the imaging contrast performance, hydrogel-based microdroplets were designed for both US blood flow and PA imaging in this study. The microdroplets served as carriers for PA contrast agent solution in the innermost part while oil and hydrogel formed the inner and outer layers of the droplets. In vitro experiments firstly demonstrated the dual modality contrast effects of the microdroplets on US flow determination and PA imaging. In vivo experiments were then carried out in both healthy nude mice and nude mice with subcutaneous tumor to validate the contrast effects and to monitor the duration of contrast effects in animals. Using the dual-modality microdroplets, we were able to obtain distinct edges of tumor and blood flow mapping of the tumor microvascular with improved sensitivity up to 11.09 dB for PA and 6.69 dB for US flow. Besides, the in vivo evaluation with microdroplets showed US flow enhancement for more than 60 min. Therefore, the microdroplets are able to provide the contrast effects for both US flow and PA in a relative long duration and have potential to be applied in the tumor related diagnoses and studies.

scholarly journals Click chemistry enables preclinical evaluation of targeted epigenetic therapies

Science ◽  
2017 ◽  
Vol 356 (6345) ◽  
pp. 1397-1401 ◽  
Author(s):  
Dean S. Tyler ◽  
Johanna Vappiani ◽  
Tatiana Cañeque ◽  
Enid Y. N. Lam ◽  
Aoife Ward ◽  
...  
Keyword(s):  
Click Chemistry ◽  
Molecular Probes ◽  
Regulatory Function ◽  
Cellular Mechanisms ◽  
Differential Distribution ◽  
Bet Inhibitors ◽  
Wide Range ◽  
Transcriptional Changes

The success of new therapies hinges on our ability to understand their molecular and cellular mechanisms of action. We modified BET bromodomain inhibitors, an epigenetic-based therapy, to create functionally conserved compounds that are amenable to click chemistry and can be used as molecular probes in vitro and in vivo. We used click proteomics and click sequencing to explore the gene regulatory function of BRD4 (bromodomain containing protein 4) and the transcriptional changes induced by BET inhibitors. In our studies of mouse models of acute leukemia, we used high-resolution microscopy and flow cytometry to highlight the heterogeneity of drug activity within tumor cells located in different tissue compartments. We also demonstrate the differential distribution and effects of BET inhibitors in normal and malignant cells in vivo. This study provides a potential framework for the preclinical assessment of a wide range of drugs.

scholarly journals Development and Physiological Functions of the Lymphatic System - Insights from Genetic Studies of Lymphedema

2021 ◽  
Author(s):  
Silvia Martin-Almedina ◽  
Peter Mortimer ◽  
Pia Ostergaard
Keyword(s):  
Lymphatic System ◽  
Imaging Techniques ◽  
The Body ◽  
Genetic Studies ◽  
Disease Mechanisms ◽  
Primary Lymphedema ◽  
And Function ◽  
The Impact

Primary lymphedema is a long-term (chronic) condition characterized by tissue lymph retention and swelling that can affect any part of the body, although it usually develops in the arms or legs. Due to the relevant contribution of the lymphatic system to human physiology, while this review mainly focusses on the clinical and physiological aspects related to the regulation of fluid homeostasis and edema, clinicians need to know that the impact of lymphatic dysfunction with a genetic origin can be wide ranging. Lymphatic gene dysfunction can affect immune function so leading to infection; it can influence cancer development and spread; and it can determine fat transport so impacting on nutrition and obesity. Genetic studies and the development of imaging techniques for the assessment of lymphatic function have enabled the recognition of primary lymphedema as a heterogenic condition in terms of genetic causes and disease mechanisms. In this review, the known biological function of several genes crucial to the development and function of the lymphatic system are used as a basis for understanding normal lymphatic biology. The disease conditions originating from mutations in these genes are discussed together with a detailed clinical description of the phenotype and the up-to-date knowledge in terms of disease mechanisms acquired from in vitro and in vivo research models.

In vivo n.m.r. imaging in medicine: the Aberdeen approach, both physical and biological

1980 ◽  
Vol 289 (1037) ◽  
pp. 519-533 ◽  
Keyword(s):  
Pulse Sequence ◽  
The Body ◽  
Spin Lattice Relaxation ◽  
Surrounding Tissue ◽  
Whole Body ◽  
Spin Concentration ◽  
Stage Of Development ◽  
Wide Range

A novel magnetic field and radio frequency (1.7 MHz) pulse sequence is described for a whole body n.m.r. imaging machine under construction. Selective excitation is used to obtain signals from successive lines of proton spins (water) across the body to build up an image of a transverse section. The images display spin concentration and spin-lattice relaxation time, T 1 , separately. For a 50 % change in T 1 to be discerned in the human trunk, a spatial resolution of 2 cm 3 is expected for a 2 min scan and 0.5 cm 3 for a 30 min scan. Very preliminary images at the present incomplete stage of development show the geometrical accuracy and T 1 discrimination: an in vivo image demonstrates some of the difficulties to be overcome. In vitro measurements of normal rabbit tissue samples have been made at 24 MHz to map the T 1 distributions that can be expected from normal subjects. The transposition of this information from rabbit to man, and from 24 MHz to 2.5 MHz have been checked and the comparison shown to be meaningful. Of pathological samples, human breast tumour and human liver metastases offer a good contrast to their surrounding tissue, and an experimental investigation has shown that tissue immediately surrounding a tumour also has an elevated T 1 value. A wide range of abnormalities that are associated with abnormal fluid formation in the body may be amenable to imaging by the n.m.r. technique. Potential hazards are believed to be small in the present generation of equipment.

Push–pull type meso-ester substituted BODIPY near-infrared dyes as contrast agents for photoacoustic imaging

2017 ◽  
Vol 15 (21) ◽  
pp. 4531-4535 ◽  
Author(s):  
Yong Ni ◽  
Ravi Kumar Kannadorai ◽  
Sidney W.-K. Yu ◽  
Young-Tae Chang ◽  
Jishan Wu
Keyword(s):  
Contrast Agents ◽  
Near Infrared ◽  
Photoacoustic Imaging ◽  
Nir Absorption ◽  
Photo Stability

Push–pull meso-ester BODIPYs with intense NIR absorption and good photo-stability were used for in vitro and in vivo photoacoustic imaging.

scholarly journals Papain Ameliorates Lipid Accumulation and Inflammation in High-Fat Diet-Induced Obesity Mice and 3T3-L1 Adipocytes via AMPK Activation

2021 ◽  
Vol 22 (18) ◽  
pp. 9885
Author(s):  
Yun-Mi Kang ◽  
Hyun-Ae Kang ◽  
Divina C. Cominguez ◽  
Su-Hyun Kim ◽  
Hyo-Jin An
Keyword(s):  
Lipid Accumulation ◽  
High Fat Diet ◽  
In Vitro Models ◽  
The Body ◽  
Obese Mice ◽  
High Fat ◽  
Oil Accumulation ◽  
Wide Range

Papain is a proteolytic enzyme present in the leaves, fruits, roots, and latex of the Carica papaya (papaya) plant. Although it exhibits a wide range of activities, there are no reports on the anti-obesity effects of papain. This study examined the anti-obesity effect and obesity-involved anti-inflammatory mechanism of papain in in vivo and in vitro models using high-fat diet (HFD)-induced obese mice and 3T3-L1 preadipocytes. Oral administration of papain reduced HFD-induced weight of the body, liver, and adipose tissues of mice. Papain also reduced hepatic lipid accumulation and adipocyte size. Moreover, serum total cholesterol and triglyceride levels were markedly reduced in papain-treated mice. In addition, papain inhibited the differentiation of preadipocytes and oil accumulation in 3T3-L1 preadipocytes and rat primary preadipocytes. Mechanistically, papain significantly downregulated the protein levels of key adipogenesis regulators and reversed the expression of pro-inflammatory cytokines and adipokines in HFD-induced obese mice and 3T3-L1 preadipocytes. Papain also markedly enhanced activation of the AMP-activated protein kinase pathway in both models. Collectively, these results suggest that papain exerts anti-obesity effects in HFD-induced mice and 3T3-L1 preadipocytes by regulating levels of adipogenic factors involved in lipid metabolism and inflammation; thus, it could be useful in the prevention and treatment of obesity.

scholarly journals Glutamine: Metabolism and Immune Function, Supplementation and Clinical Translation

Nutrients ◽  
2018 ◽  
Vol 10 (11) ◽  
pp. 1564 ◽  
Author(s):  
Vinicius Cruzat ◽  
Marcelo Macedo Rogero ◽  
Kevin Noel Keane ◽  
Rui Curi ◽  
Philip Newsholme
Keyword(s):  
Amino Acid ◽  
The Body ◽  
Glutamine Metabolism ◽  
In Vivo Studies ◽  
Glutamine Supplementation ◽  
Bacterial Killing ◽  
Nutrition Supplementation ◽  
Wide Range

Glutamine is the most abundant and versatile amino acid in the body. In health and disease, the rate of glutamine consumption by immune cells is similar or greater than glucose. For instance, in vitro and in vivo studies have determined that glutamine is an essential nutrient for lymphocyte proliferation and cytokine production, macrophage phagocytic plus secretory activities, and neutrophil bacterial killing. Glutamine release to the circulation and availability is mainly controlled by key metabolic organs, such as the gut, liver, and skeletal muscles. During catabolic/hypercatabolic situations glutamine can become essential for metabolic function, but its availability may be compromised due to the impairment of homeostasis in the inter-tissue metabolism of amino acids. For this reason, glutamine is currently part of clinical nutrition supplementation protocols and/or recommended for immune suppressed individuals. However, in a wide range of catabolic/hypercatabolic situations (e.g., ill/critically ill, post-trauma, sepsis, exhausted athletes), it is currently difficult to determine whether glutamine supplementation (oral/enteral or parenteral) should be recommended based on the amino acid plasma/bloodstream concentration (also known as glutaminemia). Although the beneficial immune-based effects of glutamine supplementation are already established, many questions and evidence for positive in vivo outcomes still remain to be presented. Therefore, this paper provides an integrated review of how glutamine metabolism in key organs is important to cells of the immune system. We also discuss glutamine metabolism and action, and important issues related to the effects of glutamine supplementation in catabolic situations.

scholarly journals Fluorescence/photoacoustic imaging-guided nanomaterials for highly efficient cancer theragnostic agent

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Vu Hoang Minh Doan ◽  
Van Tu Nguyen ◽  
Sudip Mondal ◽  
Thi Mai Thien Vo ◽  
Cao Duong Ly ◽  
...  
Keyword(s):  
Near Infrared ◽  
High Efficiency ◽  
Imaging System ◽  
Photoacoustic Imaging ◽  
Imaging Techniques ◽  
Non Invasive ◽  
Cell Ablation ◽  
Tumor Tissues

AbstractImaging modalities combined with a multimodal nanocomposite contrast agent hold great potential for significant contributions in the biomedical field. Among modern imaging techniques, photoacoustic (PA) and fluorescence (FL) imaging gained much attention due to their non-invasive feature and the mutually supportive characteristic in terms of spatial resolution, penetration depth, imaging sensitivity, and speed. In this present study, we synthesized IR783 conjugated chitosan–polypyrrole nanocomposites (IR-CS–PPy NCs) as a theragnostic agent used for FL/PA dual-modal imaging. A customized FL and photoacoustic imaging system was constructed to perform required imaging experiments and create high-contrast images. The proposed nanocomposites were confirmed to have great biosafety, essentially a near-infrared (NIR) absorbance property with enhanced photostability. The in vitro photothermal results indicate the high-efficiency MDA-MB-231 breast cancer cell ablation ability of IR-CS–PPy NCs under 808 nm NIR laser irradiation. The in vivo PTT study revealed the complete destruction of the tumor tissues with IR-CS–PPy NCs without further recurrence. The in vitro and in vivo results suggest that the demonstrated nanocomposites, together with the proposed imaging systems could be an effective theragnostic agent for imaging-guided cancer treatment.

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