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1.
Cancer Rep (Hoboken) ; 6(2): e1764, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36607830

RESUMO

BACKGROUND: Cancer is characterized by the rampant proliferation, growth, and infiltration of malignantly transformed cancer cells past their normal boundaries into adjacent tissues. It is the leading cause of death worldwide, responsible for approximately 19.3 million new diagnoses and 10 million deaths globally in 2020. In the United States alone, the estimated number of new diagnoses and deaths is 1.9 million and 609 360, respectively. Implementation of currently existing cancer diagnostic techniques such as positron emission tomography (PET), X-ray computed tomography (CT), and magnetic resonance spectroscopy (MRS), and molecular diagnostic techniques, have enabled early detection rates and are instrumental not only for the therapeutic management of cancer patients, but also for early detection of the cancer itself. The effectiveness of these cancer screening programs are heavily dependent on the rate of accurate precursor lesion identification; an increased rate of identification allows for earlier onset treatment, thus decreasing the incidence of invasive cancer in the long-term, and improving the overall prognosis. Although these diagnostic techniques are advantageous due to lack of invasiveness and easier accessibility within the clinical setting, several limitations such as optimal target definition, high signal to background ratio and associated artifacts hinder the accurate diagnosis of specific types of deep-seated tumors, besides associated high cost. In this review we discuss various imaging, molecular, and low-cost diagnostic tools and related technological advancements, to provide a better understanding of cancer diagnostics, unraveling new opportunities for effective management of cancer, particularly in low- and middle-income countries (LMICs). RECENT FINDINGS: Herein we discuss various technological advancements that are being utilized to construct an assortment of new diagnostic techniques that incorporate hardware, image reconstruction software, imaging devices, biomarkers, and even artificial intelligence algorithms, thereby providing a reliable diagnosis and analysis of the tumor. Also, we provide a brief account of alternative low cost-effective cancer therapy devices (CryoPop®, LumaGEM®, MarginProbe®) and picture archiving and communication systems (PACS), emphasizing the need for multi-disciplinary collaboration among radiologists, pathologists, and other involved specialties for improving cancer diagnostics. CONCLUSION: Revolutionary technological advancements in cancer imaging and molecular biology techniques are indispensable for the accurate diagnosis and prognosis of cancer.


Assuntos
Inteligência Artificial , Neoplasias , Humanos , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X , Prognóstico
2.
Int J Radiat Biol ; 99(4): 681-691, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35946994

RESUMO

PURPOSE: Citrobacter rodentium (CR) infection coupled with blocking Notch/Wnt signaling via γ-secretase inhibitor dibenzazepine (DBZ) disrupts the gastro-intestinal (GI) barrier and induces colitis, akin to ionizing radiation (IR)-induced GI-injury. We investigated the effects of 2-deoxy-D-glucose (2-DG) to ameliorate the CR-DBZ-induced GI damage. MATERIALS AND METHODS: NIH:Swiss outbred mice were inoculated with 109CFUs of CR orally. DBZ was administered intraperitoneally (10 µM/kg b.wt; for 10 days 2 days post-CR infection). Mice were fed with 0.4% 2-DG (w/v) daily in drinking water. For microbiota depletion, antibiotics (Abx), 1 g/l metronidazole, and 0.2 g/l ciprofloxacin were administered for 10 days in drinking water. Oxidative stress, survival assay, colonic crypt hyperplasia, Notch/Wnt downstream signaling, immunomodulation, and bacterial dysbiosis were measured. RESULTS: We show that real-time visualization of reactive oxygen species (ROS) is similar during CR-induced colonic infection and IR-induced GI-damage. The histology revealed that dietary 2-DG mitigates CR + DBZ-induced colitis and improves survival compared with CR + DBZ alone. These changes were phenocopied in Abx-treated mice. Both 2-DG and Abx reduced dysbiosis, increased proliferation, inhibited pro-inflammatory response, and restored Hes-1 and ß-catenin protein levels, in the crypts. CONCLUSION: The energy disruptor 2-DG mitigates bacterial infection and its responsive hyperplasia/colitis, indicating its utility as a mitigator of infection/IR-induced GI-damage.


Assuntos
Colite , Dibenzazepinas , Água Potável , Infecções por Enterobacteriaceae , Camundongos , Animais , Hiperplasia/patologia , Citrobacter rodentium , Glucose , Disbiose/patologia , Colite/induzido quimicamente , Colite/tratamento farmacológico , Colite/microbiologia , Colo/microbiologia , Colo/patologia , Infecções por Enterobacteriaceae/tratamento farmacológico , Infecções por Enterobacteriaceae/metabolismo , Infecções por Enterobacteriaceae/microbiologia , Dibenzazepinas/farmacologia , Desoxiglucose/farmacologia , Camundongos Endogâmicos C57BL
3.
Cancer Manag Res ; 14: 1421-1429, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35431581

RESUMO

Recent technological advancements have increased the efficacy of radiotherapy, leading to effective management of cancer patients with enhanced patient survival and improved quality of life. Several important developments like multileaf collimator, integration of imaging techniques like positron emission tomography (PET) and computed tomography (CT), involvement of advanced dose calculation algorithms, and delivery techniques have increased tumor dose distribution and decreased normal tissue toxicity. Three-dimensional conformal radiotherapy (3DCRT), intensity-modulated radiotherapy (IMRT), stereotactic radiotherapy, image-guided radiotherapy (IGT), and particle therapy have facilitated the planning procedures, accurate tumor delineation, and dose estimation for effective personalized treatment. In this review, we present the technological advancements in various types of EBRT methods and discuss their clinical utility and associated limitations. We also reveal novel approaches of using biocompatible yttrium oxide scintillator-photosensitizer complex (YSM) that can generate X-ray induced cytotoxic reactive oxygen species, facilitating X-ray activated photodynamic therapy (XPDT (external beam) and/or iXPDT (internal X-ray source)) and azido-derivatives of 2-deoxy-D-glucose (2-DG) as agents for site-specific radiation-induced DNA damage.

4.
Int J Radiat Biol ; 96(11): 1323-1328, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32910699

RESUMO

COVID-19, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a pandemic disease and is the major cause of deaths worldwide. The clinical complexities (inflammation, cytokine storm, and multi-organ dysfunction) associated with COVID-19 poses constraints to effective management of critically ill COVID-19 patients. Low dose radiation therapy (LDRT) has been evaluated as a potential therapeutic modality for COVID-19 pneumonia. However, due to heterogeneity in disease manifestation and inter-individual variations, effective planning for LDRT is limited for this large-scale event. 2-deoxy-D-glucose (2-DG) has emerged as a polypharmacological agent for COVID-19 treatment due to its effects on the glycolytic pathway, anti-inflammatory action, and interaction with viral proteins. We suggest that 2-DG will be a potential adjuvant to enhance the efficacy of LDRT in the treatment of COVID-19 pneumonia. Withal, azido analog of 2-DG, 2-azido-2-DG can produce rapid catastrophic oxidative stress and quell the cytokine storm in critically ill COVID-19 patients.


Assuntos
Betacoronavirus , Infecções por Coronavirus/terapia , Síndrome da Liberação de Citocina/terapia , Desoxiglucose/uso terapêutico , Pneumonia Viral/terapia , COVID-19 , Terapia Combinada , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/metabolismo , Desoxiglucose/farmacologia , Humanos , Pandemias , Pneumonia Viral/imunologia , Pneumonia Viral/metabolismo , Dosagem Radioterapêutica , SARS-CoV-2
5.
Environ Res ; 168: 130-140, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30296640

RESUMO

This article presents the results of a workshop held in Stirling, Scotland in June 2018, called to examine critically the effects of low-dose ionising radiation on the ecosphere. The meeting brought together participants from the fields of low- and high-dose radiobiology and those working in radioecology to discuss the effects that low doses of radiation have on non-human biota. In particular, the shape of the low-dose response relationship and the extent to which the effects of low-dose and chronic exposure may be predicted from high dose rate exposures were discussed. It was concluded that high dose effects were not predictive of low dose effects. It followed that the tools presently available were deemed insufficient to reliably predict risk of low dose exposures in ecosystems. The workshop participants agreed on three major recommendations for a path forward. First, as treating radiation as a single or unique stressor was considered insufficient, the development of a multidisciplinary approach is suggested to address key concerns about multiple stressors in the ecosphere. Second, agreed definitions are needed to deal with the multiplicity of factors determining outcome to low dose exposures as a term can have different meanings in different disciplines. Third, appropriate tools need to be developed to deal with the different time, space and organisation level scales. These recommendations permit a more accurate picture of prospective risks.


Assuntos
Relação Dose-Resposta à Radiação , Proteção Radiológica , Radiação Ionizante , Animais , Doses de Radiação , Exposição à Radiação , Escócia
7.
Am J Physiol Gastrointest Liver Physiol ; 307(1): G1-15, 2014 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-24789206

RESUMO

The human intestinal tract harbors a complex ecosystem of commensal bacteria that play a fundamental role in the well-being of their host. There is a general consensus that diet rich in plant-based foods has many advantages in relation to the health and well-being of an individual. In adults, diets that have a high proportion of fruit and vegetables and a low consumption of meat are associated with a highly diverse microbiota and are defined by a greater abundance of Prevotella compared with Bacteroides, whereas the reverse is associated with a diet that contains a low proportion of plant-based foods. In a philosophical term, our consumption of processed foods, widespread use of antibiotics and disinfectants, and our modern lifestyle may have forever altered our ancient gut microbiome. We may never be able to identify or restore our microbiomes to their ancestral state, but dietary modulation to manipulate specific gut microbial species or groups of species may offer new therapeutic approaches to conditions that are prevalent in modern society, such as functional gastrointestinal disorders, obesity, and age-related nutritional deficiency. We believe that this will become an increasingly important area of health research.


Assuntos
Quimioprevenção/métodos , Dieta , Gastroenteropatias/prevenção & controle , Trato Gastrointestinal/microbiologia , Estilo de Vida , Microbiota , Compostos Fitoquímicos/uso terapêutico , Comportamento de Redução do Risco , Animais , Antibacterianos/efeitos adversos , Dieta/efeitos adversos , Desinfetantes/efeitos adversos , Disbiose , Frutas , Gastroenteropatias/epidemiologia , Gastroenteropatias/microbiologia , Gastroenteropatias/fisiopatologia , Trato Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/fisiopatologia , Interações Hospedeiro-Patógeno , Humanos , Carne , Microbiota/efeitos dos fármacos , Fatores de Risco , Verduras
8.
Radiat Res ; 177(4): 483-95, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22404738

RESUMO

Precise dose delivery to malignant tissue in radiotherapy is of paramount importance for treatment efficacy while minimizing morbidity of surrounding normal tissues. Current conventional imaging techniques, such as magnetic resonance imaging (MRI) and computerized tomography (CT), are used to define the three-dimensional shape and volume of the tumor for radiation therapy. In many cases, these radiographic imaging (RI) techniques are ambiguous or provide limited information with regard to tumor margins and histopathology. Molecular imaging (MI) modalities, such as positron emission tomography (PET) and single photon-emission computed-tomography (SPECT) that can characterize tumor tissue, are rapidly becoming routine in radiation therapy. However, their inherent low spatial resolution impedes tumor delineation for the purposes of radiation treatment planning. This review will focus on applications of nanotechnology to synergize imaging modalities in order to accurately highlight, as well as subsequently target, tumor cells. Furthermore, using such nano-agents for imaging, simultaneous coupling of novel therapeutics including radiosensitizers can be delivered specifically to the tumor to maximize tumor cell killing while sparing normal tissue.


Assuntos
Imagem Molecular/métodos , Nanotecnologia/métodos , Neoplasias/radioterapia , Radioterapia/métodos , Animais , Anexina A5 , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacocinética , Antineoplásicos/uso terapêutico , Meios de Contraste/administração & dosagem , Portadores de Fármacos , Corantes Fluorescentes , Fluorometria/métodos , Gadolínio/administração & dosagem , Humanos , Nanopartículas/uso terapêutico , Neoplasias/química , Compostos de Organotecnécio , Tomografia por Emissão de Pósitrons/métodos , Pontos Quânticos , Radiossensibilizantes/administração & dosagem , Radiossensibilizantes/uso terapêutico , Compostos Radiofarmacêuticos/farmacocinética , Compostos Radiofarmacêuticos/uso terapêutico , Planejamento da Radioterapia Assistida por Computador , Análise Espectral Raman , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Imagem Corporal Total/métodos
9.
Comput Methods Programs Biomed ; 99(1): 88-97, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20133007

RESUMO

A radiographic system is optimized for the contrast inherent to small animals and is developed for a multi-modal imaging system devised for in-vivo studies. The range of X-ray energies utilized (generally considered "soft X-rays") enables enhanced spatial resolution and superior contrast for detailed study of the mouse anatomy and smaller specimens. Despite the difficulties presented by the complicated energy spectrum of soft X-rays, relevant system calibrations for bone measures are described in detail and applied to the mouse. Further, long-bone symmetry modeling using a cylindrical projection is applied to the planar density image, providing convenient bone density estimates that are consistent with other methodologies.


Assuntos
Osso e Ossos/diagnóstico por imagem , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Animais , Densidade Óssea , Camundongos
10.
Bioconjug Chem ; 21(3): 427-35, 2010 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-20163157

RESUMO

IgG antibodies were conjugated to Kodak X-Sight nanospheres to develop fluorescent-labeled antibodies using two different synthetic routes: one involving the DTT reduction method, and the other involving Traut's Reagent modification method. These two methods result in different conjugation efficiencies and different performances in antigen detection. Western blotting shows that the nanosphere-IgG antibody conjugates synthesized using the DTT reduction method are more immunospecific than the conjugates synthesized using Traut's Reagent modification method. In addition, the conjugates synthesized using DTT reduction also show higher antigen detection sensitivity than other commercially available fluorescent-IgG antibody conjugates, including Alexa Fluor, Qdot, and CyDye conjugates.


Assuntos
Anticorpos/química , Antígenos/análise , Fluorescência , Imunoglobulina G/química , Imunoglobulina G/imunologia , Látex/química , Nanosferas/química , Anticorpos/imunologia , Reações Antígeno-Anticorpo , Antígenos/imunologia , Estrutura Molecular
11.
J Biol Chem ; 277(51): 49167-74, 2002 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-12364321

RESUMO

Apocalmodulin and Ca(2+) calmodulin bind to overlapping sites on the ryanodine receptor skeletal form, RYR1, but have opposite functional effects on channel activity. Suramin, a polysulfonated napthylurea, displaces both forms of calmodulin, leading to an inhibition of activity at low Ca(2+) and an enhancement of activity at high Ca(2+). Calmodulin binding motifs on RYR1 are also able to directly interact with the carboxy-terminal tail of the transverse tubule dihydropyridine receptor (DHPR) (Sencer, S., Papineni, R. V., Halling, D. B., Pate, P., Krol, J., Zhang, J. Z., and Hamilton, S. L. (2001) J. Biol. Chem. 276, 38237-38241). Suramin binds directly to a peptide that corresponds to the calmodulin binding site of RYR1 (amino acids 3609-3643) and blocks the interaction of this peptide with both calmodulin and the carboxyl-terminal tail of the DHPR alpha(1)-subunit. Suramin, added to the internal solution of voltage-clamped skeletal myotubes, produces a concentration-dependent increase in the maximal magnitude of voltage-gated Ca(2+) transients without significantly altering L-channel Ca(2+) channel conducting activity. Together, these results suggest that an interaction between the carboxyl-terminal tail of the DHPR alpha(1)-subunit with the calmodulin binding region of RYR1 serves to limit sarcoplasmic reticulum Ca(2+) release during excitation-contraction coupling and that suramin-induced potentiation of voltage-gated Ca(2+) release involves a relief of this inhibitory interaction.


Assuntos
Calmodulina/química , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Suramina/farmacologia , Motivos de Aminoácidos , Animais , Antineoplásicos/farmacologia , Sítios de Ligação , Cálcio/metabolismo , Bovinos , Células Cultivadas , Relação Dose-Resposta a Droga , Eletroforese em Gel de Poliacrilamida , Metionina/química , Camundongos , Músculo Esquelético/citologia , Técnicas de Patch-Clamp , Peptídeos/química , Ligação Proteica , Estrutura Terciária de Proteína , Coelhos , Rianodina/metabolismo , Retículo Sarcoplasmático/metabolismo , Espectrometria de Fluorescência , Triptofano/química
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