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Fungal metabolites represent an underutilized resource in the development of novel anticancer drugs. This review will focus on the promising fungal nephrotoxin orellanine, found in mushrooms including Cortinarius orellanus (Fools webcap). Emphasis will be placed on its historical significance, structural features, and associated toxicomechanics. Chromatographic methods for analysis of the compound and its metabolites, its synthesis, and chemotherapeutic potential are also discussed. Although orellanine's exceptional selectivity for proximal tubular cells is well documented, the mechanics of its toxicity in kidney tissue remains disputed. Here, the most commonly proposed hypotheses are detailed in the context of the molecule's structure, the symptoms seen following ingestion, and its characteristic prolonged latency period. Chromatographic analysis of orellanine and its related substances remains challenging, while biological evaluation of the compound is complicated by uncertainty regarding the role of active metabolites. This has limited efforts to structurally refine the molecule; despite numerous established methods for its synthesis, there is minimal published material on how orellanine's structure might be optimized for therapeutic use. Despite these obstacles, orellanine has generated promising data in preclinical studies of metastatic clear cell renal cell carcinoma, leading to the early 2022 announcement of phase I/II trials in humans.
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Agaricales , Micotoxinas , Neoplasias , Humanos , Micotoxinas/análise , Neoplasias/tratamento farmacológico , 2,2'-Dipiridil/química , 2,2'-Dipiridil/metabolismo , 2,2'-Dipiridil/toxicidade , Agaricales/metabolismoRESUMO
PURPOSE: To establish molecular magnetic resonance (MR) imaging instruments for in vivo characterization of the immune response to hepatic radiofrequency (RF) ablation using cell-specific immunoprobes. MATERIALS AND METHODS: Seventy-two C57BL/6 wild-type mice underwent standardized hepatic RF ablation (70 °C for 5 minutes) to generate a coagulation area measuring 6-7 mm in diameter. CD68+ macrophage periablational infiltration was characterized with immunohistochemistry 24 hours, 72 hours, 7 days, and 14 days after ablation (n = 24). Twenty-one mice were subjected to a dose-escalation study with either 10, 15, 30, or 60 mg/kg of rhodamine-labeled superparamagnetic iron oxide nanoparticles (SPIONs) or 2.4, 1.2, or 0.6 mg/kg of gadolinium-160 (160Gd)-labeled CD68 antibody for assessment of the optimal in vivo dose of contrast agent. MR imaging experiments included 9 mice, each receiving 10-mg/kg SPIONs to visualize phagocytes using T2∗-weighted imaging in a horizontal-bore 9.4-T MR imaging scanner, 160Gd-CD68 for T1-weighted MR imaging of macrophages, or 0.1-mmol/kg intravenous gadoterate (control group). Radiological-pathological correlation included Prussian blue staining, rhodamine immunofluorescence, imaging mass cytometry, and immunohistochemistry. RESULTS: RF ablation-induced periablational infiltration (206.92 µm ± 12.2) of CD68+ macrophages peaked at 7 days after ablation (P < .01) compared with the untreated lobe. T2∗-weighted MR imaging with SPION contrast demonstrated curvilinear T2∗ signal in the transitional zone (TZ) (186 µm ± 16.9), corresponsing to Iron Prussian blue staining. T1-weighted MR imaging with 160Gd-CD68 antibody showed curvilinear signal in the TZ (164 µm ± 3.6) corresponding to imaging mass cytometry. CONCLUSIONS: Both SPION-enhanced T2∗-weighted and 160Gd-enhanced T1-weighted MR imaging allow for in vivo monitoring of macrophages after RF ablation, demonstrating the feasibility of this model to investigate local immune responses.
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Fígado , Ablação por Radiofrequência , Animais , Camundongos , Camundongos Endogâmicos C57BL , Fígado/patologia , Imageamento por Ressonância Magnética/métodos , Macrófagos , Imunidade , Meios de ContrasteRESUMO
Extremely small paramagnetic iron oxide nanoparticles (FeMNPs) (<5 nm) can enhance positive magnetic resonance imaging (MRI) contrast by shortening the longitudinal relaxation time of water (T1), but these nanoparticles experience rapid renal clearance. Here, magnetic protein nanoparticles (MPNPs) are synthesized from protein-conjugated citric acid coated FeMNPs (c-FeMNPs) without loss of the T1 MRI properties and tagged with fluorescent dye (f-MPNPs) for optical cerebrovascular imaging. The c-FeMNPs shows average size 3.8 ± 0.7 nm with T1 relaxivity (r1) of 1.86 mM-1 s-1 and transverse/longitudinal relaxivity ratio (r2/r1) of 2.53 at 11.7 T. The f-MPNPs show a higher r1 value of 2.18 mM-1 s-1 and r2/r1 ratio of 2.88 at 11.7 T, which generates excellent positive MRI contrast. In vivo cerebral angiography with f-MPNPs enables detailed microvascular contrast enhancement for differentiation of major blood vessels of murine brain, which corresponds well with whole brain three-dimensional time-of-flight MRI angiograms (17 min imaging time with 60 ms repetition time and 40 µm isotropic voxels). The real-time fluorescence angiography enables unambiguous detection of brain capillaries with diameter < 40 µm. Biodistribution examination revealed that f-MPNPs were safely cleared by the organs like the liver, spleen, and kidneys within a day after injection. Blood biochemical assays demonstrated no risk of iron overload in both rats and mice. With hybrid neuroimaging technologies (e.g., MRI-optical) on the rise, f-MPNPs built on this platform can generate exciting neuroscience applications.
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Fígado , Baço , Animais , Ratos , Camundongos , Angiografia Cerebral , Distribuição Tecidual , Espectroscopia de Ressonância MagnéticaRESUMO
The efficacy and tolerability of tubulin binding agents are hampered by their low specificity for cancer cells like most clinically used anticancer agents. To improve specificity, tubulin binding agents have been covalently conjugated to agents that target cancer cells to give actively targeted drug conjugates. These conjugates are designed to increase uptake of the drug by cancer cells while having limited uptake by normal cells, thereby improving efficacy and tolerability. Approaches used include an attachment to small molecules, polysaccharides, peptides, proteins, and antibodies that exploit the overexpression of receptors for these substances. Antibody targeted strategies have been the most successful to date, with six such examples having gained clinical approval. Many other conjugate types, especially those targeting the folate receptor, have shown promising efficacy and toxicity profiles in pre-clinical models and in early-stage clinical studies. Presented herein is a discussion of the success or otherwise of the recent strategies used to form these actively targeted conjugates.
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Antimitóticos , Antineoplásicos , Antineoplásicos/química , Fenômenos Químicos , Sistemas de Liberação de Medicamentos , Humanos , Tubulina (Proteína)RESUMO
In the present research, a rapid, simple and efficient green method is used for the incorporation of silver nanoparticles (AgNPs) into poly(ethylene glycol) methacrylate (PEGMA) to create biocatalysts with excellent properties for pharmaceutical purpose. In the first phase, Caralluma tuberculata capped AgNPs (Ca-AgNPs) were prepared using green synthetic approach and in the second phase Caralluma tuberculata capped AgNPs were hybridized with poly(ethylene glycol) methacrylate to form PEGMA-AgNPs. Both the virgin (naked or uncapped) and polymer-capped materials were characterized spectroscopically and their results were compared. Fourier transform infrared spectroscopy showed no new peak after the capping procedure, showing that only physical interactions takes place during capping. After PEGMA capping, the spectra of the AgNPs red shifted (from 450 nm to 520 nm) and the overall particle size of AgNPs increased. Catalytic activity of the nanoparticles and hybrid system were tested by choosing the catalytic reduction of 4-nitrophenol (4-NP) as a model reaction. Both synthesized NPs and polymer capped NPs exhibits catalytic activity for the reduction of 4-NP to 4-aminophenol. The polymer hybrid exhibits remarkable antiproliferative, antioxidant, cytotoxic, antidiabetic and antileishmanial activities.
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Nanopartículas Metálicas , Prata , Prata/química , Nanopartículas Metálicas/química , Antioxidantes/química , Polietilenoglicóis/química , MetacrilatosRESUMO
An acidic extracellular space is a hallmark of the tumor microenvironment. Acidosis has been postulated to promote the aggressive and invasive characteristics of tumors and also inhibit the therapeutic response, particularly in the context of novel immunotherapies. Therefore, methods to quantitatively measure the extracellular pH (pHe) are needed. Here we describe a magnetic resonance spectroscopic imaging (MRSI) technique termed Biosensor Imaging of Redundant Deviation in Shifts (BIRDS), which uses the pH-dependent chemical shifts of nonexchangeable protons of lanthanide-based contrast agents to generate quantitative spatial pHe maps. We assess this method in the context of evaluating the acidic pHe and therapeutic response in glioblastoma in rodents, where normalization of the pHe upon therapy can serve as a quantitative readout of successful drug delivery to the tumor.
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Glioblastoma , Elementos da Série dos Lantanídeos , Meios de Contraste/química , Glioblastoma/tratamento farmacológico , Humanos , Concentração de Íons de Hidrogênio , Imageamento por Ressonância Magnética/métodos , Microambiente TumoralRESUMO
Chemical exchange saturation transfer (CEST) and biosensor imaging of redundant deviation in shifts (BIRDS) methods differ respectively by detecting exchangeable and nonexchangeable proton signals by magnetic resonance. Because CEST contrast depends on both temperature and pH, simultaneous CEST and BIRDS imaging can be employed to separate these contributions. Here, we test if high-resolution pH imaging in vivo is possible with ratiometric CEST calibrated for temperature variations measured by BIRDS. Thulium- and europium-based DOTA-tetraglycinate agents, TmDOTA-(gly)4- and EuDOTA-(gly)4- , were used for high-resolution pH mapping in vitro and in vivo, using BIRDS for temperature adjustments needed for a more accurate ratiometric CEST approach. Although neither agent showed pH dependence with BIRDS in vitro in the pH range 6 to 8, each one's temperature sensitivity was enhanced when mixed because of increased redundancy. By contrast, the CEST signal of each agent was affected by the presence of the other agent in vitro. However, pH could be measured more accurately when temperature from BIRDS was detected. These in vitro calibrations with TmDOTA-(gly)4- and EuDOTA-(gly)4- enabled high-resolution pH imaging of glioblastoma in rat brains. It was concluded that temperature mapping with BIRDS can calibrate the ratiometric CEST signal from a cocktail of TmDOTA-(gly)4- and EuDOTA-(gly)4- agents to provide temperature-independent absolute pH imaging in vivo.
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Técnicas Biossensoriais , Meios de Contraste , Animais , Técnicas Biossensoriais/métodos , Compostos Heterocíclicos com 1 Anel , Concentração de Íons de Hidrogênio , Imageamento por Ressonância Magnética/métodos , RatosRESUMO
OBJECTIVES: The goal of this study was to investigate the effects of TACE using Lipiodol, Oncozene™ drug-eluting embolics (DEEs), or LUMI™-DEEs alone, or combined with bicarbonate on the metabolic and immunological tumor microenvironment in a rabbit VX2 tumor model. METHODS: VX2 liver tumor-bearing rabbits were assigned to five groups. MRI and extracellular pH (pHe) mapping using Biosensor Imaging of Redundant Deviation in Shifts (BIRDS) were performed before and after intra-arterial therapy with conventional TACE (cTACE), DEE-TACE with Idarubicin-eluting Oncozene™-DEEs, or Doxorubicin-eluting LUMI™-DEEs, each with or without prior bicarbonate infusion, and in untreated rabbits or treated with intra-arterial bicarbonate only. Imaging results were validated with immunohistochemistry (IHC) staining of cell viability (PCNA, TUNEL) and immune response (HLA-DR, CD3). Statistical analysis was performed using Mann-Whitney U test. RESULTS: pHe mapping revealed that combining cTACE with prior bicarbonate infusion significantly increased tumor pHe compared to control (p = 0.0175) and cTACE alone (p = 0.0025). IHC staining revealed peritumoral accumulation of HLA-DR+ antigen-presenting cells and CD3 + T-lymphocytes in controls. cTACE-treated tumors showed reduced immune infiltration, which was restored through combination with bicarbonate. DEE-TACE with Oncozene™-DEEs induced moderate intratumoral and marked peritumoral infiltration, which was slightly reduced with bicarbonate. Addition of bicarbonate prior to LUMI™-beads enhanced peritumoral immune cell infiltration compared to LUMI™-beads alone and resulted in the strongest intratumoral immune cell infiltration across all treated groups. CONCLUSIONS: The choice of chemoembolic regimen for TACE strongly affects post-treatment TME pHe and the ability of immune cells to accumulate and infiltrate the tumor tissue. KEY POINTS: ⢠Combining conventional transarterial chemotherapy with prior bicarbonate infusion increases the pHe towards a more physiological value (p = 0.0025). ⢠Peritumoral infiltration and intratumoral accumulation patterns of antigen-presenting cells and T-lymphocytes after transarterial chemotherapy were dependent on the choice of the chemoembolic regimen. ⢠Combination of intra-arterial treatment with Doxorubicin-eluting LUMI™-beads and bicarbonate infusion resulted in the strongest intratumoral presence of immune cells (positivity index of 0.47 for HLADR+-cells and 0.62 for CD3+-cells).
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Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Hepáticas , Animais , Carcinoma Hepatocelular/patologia , Quimioembolização Terapêutica/métodos , Doxorrubicina , Óleo Etiodado , Neoplasias Hepáticas/patologia , Coelhos , Microambiente TumoralRESUMO
Glioblastoma progression involves multifaceted changes in vascularity, cellularity, and metabolism. Capturing such complexities of the tumor niche, from the tumor core to the periphery, by magnetic resonance imaging (MRI) and spectroscopic imaging (MRSI) methods has translational impact. In human-derived glioblastoma models (U87, U251) we made simultaneous and longitudinal measurements of tumor perfusion (Fp), permeability (Ktrans), and volume fractions of extracellular (ve) and blood (vp) spaces from dynamic contrast enhanced (DCE) MRI, cellularity from apparent diffusion coefficient (ADC) MRI, and extracellular pH (pHe) from an MRSI method called Biosensor Imaging of Redundant Deviation in Shifts (BIRDS). Spatiotemporal patterns of these parameters during tumorigenesis were unique for each tumor. While U87 tumors grew faster, Fp, Ktrans, and vp increased with tumor growth in both tumors but these trends were more pronounced for U251 tumors. Perfused regions between tumor periphery and core with U87 tumors exhibited higher Fp, but Ktrans of U251 tumors remained lowest at the tumor margin, suggesting primitive vascularization. Tumor growth was uncorrelated with ve, ADC, and pHe. U87 tumors showed correlated regions of reduced ve and lower ADC (higher cellularity), suggesting ongoing proliferation. U251 tumors revealed that the tumor core had higher ve and elevated ADC (lower cellularity), suggesting necrosis development. The entire tumor was uniformly acidic (pHe 6.1-6.8) early and throughout progression, but U251 tumors were more acidic, suggesting lower aerobic glycolysis in U87 tumors. Characterizing these cancer hallmarks with DCE-MRI, ADC-MRI, and BIRDS-MRSI will be useful for exploring tumorigenesis as well as timely therapies targeted to specific vascular and metabolic aspects of the tumor microenvironment.
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Tourniquets have been used in the medical setting for centuries and have become the gold standard when preparing patients for surgery, particularly in orthopaedic surgery. Upper extremity tourniquet use improves intraoperative visibility and identification of anatomy. It also decreases blood loss intraoperatively and improves the safety of orthopaedic procedures. Despite the widespread use of tourniquets and differing methods of limb exsanguination, little research has been done quantifying its efficacy. The purpose of this study was to compare gravity exsanguination to Esmarch exsanguination of the upper extremity prior to tourniquet inflation in a large patient sample. A plethysmographic method based on water displacement served as a surrogate for the blood volume exsanguinated. Control measurements of water displacement were obtained from both upper extremities without tourniquet inflation. Water displacement was then measured with both gravity and Esmarch exsanguination techniques. Gender, handedness, height, weight, body mass index, and age were recorded for volunteers and used as covariates. Change in mean water displacement from control (un-exsanguinated) arm and gravity alone measurement was 37.2 ml. Change in mean water displacement between control arm and mean Esmarch measurement was 56.3 ml. Exsanguination using Esmarch compared to gravity alone resulted in a 51.2% increase in blood removal. Only age had a significant interaction effect for the Esmarch method. Analysis revealed that age accounted for 21.4% of all variance in blood exsanguinated using the Esmarch method when compared to the control group. The Esmarch technique was more efficacious for all demographics measured, but most efficacious in subjects who were older than 40 years. This data reaffirms that gravity exsanguination is more efficacious than no tourniquet use at all, and that the Esmarch technique is more efficacious than gravity. To our knowledge, this study is the most robust of its kind to critically and objectively compare upper extremity exsanguination methods and overall tourniquet use by age and supports the common practice of Esmarch exsanguination in orthopaedic extremity surgery.
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Perda Sanguínea Cirúrgica/estatística & dados numéricos , Exsanguinação , Procedimentos Ortopédicos , Torniquetes , Extremidade Superior/irrigação sanguínea , Adulto , Fatores Etários , Bandagens , Volume Sanguíneo/fisiologia , Feminino , Humanos , Masculino , Estudos Prospectivos , Extremidade Superior/cirurgiaRESUMO
Under normal conditions, high sodium (Na+) in extracellular (Na+e) and blood (Na+b) compartments and low Na+ in intracellular milieu (Na+i) produce strong transmembrane (ΔNa+mem) and weak transendothelial (ΔNa+end) gradients respectively, and these manifest the cell membrane potential (Vm) as well as blood-brain barrier (BBB) integrity. We developed a sodium (23Na) magnetic resonance spectroscopic imaging (MRSI) method using an intravenously-administered paramagnetic polyanionic agent to measure ΔNa+mem and ΔNa+end. In vitro 23Na-MRSI established that the 23Na signal is intensely shifted by the agent compared to other biological factors (e.g., pH and temperature). In vivo 23Na-MRSI showed Na+i remained unshifted and Na+b was more shifted than Na+e, and these together revealed weakened ΔNa+mem and enhanced ΔNa+end in rat gliomas (vs. normal tissue). Compared to normal tissue, RG2 and U87 tumors maintained weakened ΔNa+mem (i.e., depolarized Vm) implying an aggressive state for proliferation, whereas RG2 tumors displayed elevated ∆Na+end suggesting altered BBB integrity. We anticipate that 23Na-MRSI will allow biomedical explorations of perturbed Na+ homeostasis in vivo.
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Barreira Hematoencefálica/metabolismo , Glioma/metabolismo , Sódio/metabolismo , Transporte Biológico , Biomarcadores , Metabolismo Energético , Glioma/diagnóstico por imagem , Glioma/patologia , Imageamento por Ressonância Magnética , Análise EspectralRESUMO
The design, implementation and evaluation of a year 1 pharmacy-integrated learning component, using the World Health Organisation's (WHO) analgesic ladder as a scaffold for case-based learning, is described. A novel aspect of the integrated component is the mapping of the cases to the national Core Competency Framework (CCF) for Pharmacists in Ireland and to the school's own cross-cutting curricular integration themes. The integrated cases were student led and delivered through peer-to-peer teaching for 68 first-year pharmacy students. The integrated cases mapped strongly to three of the CCF's domains, namely, personal skills, organisation and management skills and supply of medicines. With regard to the school's curricular integrative themes, the cases mapped strongly to the curricular integration themes of professionalism and communications; medicines sourcing, production and use; and safe and rational use of medicines. Highlights from an anonymous online student survey were the recognition by students of the importance of core science knowledge for practice, the enabling of integrated learning and the suitability of the integrated component for entry-level. While a majority of students were found to favour individual work over group work, future iterations will need to consider a greater degree of group work with a view to reducing the volume of content and time required to complete the cases.
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Nursing home residents experience death and injury at a disproportionately higher rate than other populations during and after a disaster. This paper addresses the complex chronic conditions of vulnerable residents that will become even more challenging due to compounding effects from continued disasters and rapid population aging. In 2016, the Centers for Medicare and Medicaid Services (CMS) established national emergency preparedness requirements for long-term care (LTC) and skilled nursing (SN) facilities. The problems facing nursing facilities created by an increasing population to serve, present a challenge to meeting the highest level of requirements and responsibilities for healthcare preparedness. This paper argues that nursing facility personnel are required to participate in an unfamiliar culture of operational processes, using terminology foreign to their profession, in an environment requiring planning and decision-making skills using organisational concepts they most likely have never experienced. Furthermore, unlike hospitals, LTC and SN facility staff have not had extensive access to standardised training to meet the current requirements. The paper concludes that this environment adversely affects emergency managers and unnecessarily increases their planning and operational burden.
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Defesa Civil , Planejamento em Desastres , Medicaid , Medicare , Idoso , Humanos , Casas de Saúde , Estados UnidosRESUMO
PURPOSE: To investigate toxicity, efficacy, and microenvironmental effects of idarubicin-loaded 40-µm and 100-µm drug-eluting embolic (DEE) transarterial chemoembolization in a rabbit liver tumor model. MATERIALS AND METHODS: Twelve male New Zealand White rabbits with orthotopically implanted VX2 liver tumors were assigned to DEE chemoembolization with 40-µm (n = 5) or 100-µm (n = 4) ONCOZENE microspheres or no treatment (control; n = 3). At 24-72 hours postprocedurally, multiparametric magnetic resonance (MR) imaging including dynamic contrast-enhanced (DCE), diffusion-weighted imaging (DWI), and biosensor imaging of redundant deviation in shifts (BIRDS) was performed to assess extracellular pH (pHe), followed by immediate euthanasia. Laboratory parameters and histopathologic ex vivo analysis included fluorescence confocal microscopy and immunohistochemistry. RESULTS: DCE MR imaging demonstrated a similar degree of devascularization of embolized tumors for both microsphere sizes (mean arterial enhancement, 8% ± 12 vs 36% ± 51 in controls; P = .07). Similarly, DWI showed postprocedural increases in diffusion across the entire lesion (apparent diffusion coefficient, 1.89 × 10-3 mm2/s ± 0.18 vs 2.34 × 10-3 mm2/s ± 0.18 in liver; P = .002). BIRDS demonstrated profound tumor acidosis at baseline (mean pHe, 6.79 ± 0.08 in tumor vs 7.13 ± 0.08 in liver; P = .02) and after chemoembolization (6.8 ± 0.06 in tumor vs 7.1 ± 0.04 in liver; P = .007). Laboratory and ex vivo analyses showed central tumor core penetration and greater increase in liver enzymes for 40-µm vs 100-µm microspheres. Inhibition of cell proliferation, intratumoral hypoxia, and limited idarubicin elution were equally observed with both sphere sizes. CONCLUSIONS: Noninvasive multiparametric MR imaging visualized chemoembolic effects in tumor and tumor microenvironment following DEE chemoembolization. Devascularization, increased hypoxia, coagulative necrosis, tumor acidosis, and limited idarubicin elution suggest ischemia as the predominant therapeutic mechanism. Substantial size-dependent differences indicate greater toxicity with the smaller microsphere diameter.
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Antibióticos Antineoplásicos/administração & dosagem , Quimioembolização Terapêutica , Idarubicina/administração & dosagem , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Microambiente Tumoral , Animais , Técnicas Biossensoriais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Imagem de Difusão por Ressonância Magnética , Concentração de Íons de Hidrogênio , Neoplasias Hepáticas Experimentais/diagnóstico por imagem , Neoplasias Hepáticas Experimentais/metabolismo , Neoplasias Hepáticas Experimentais/patologia , Masculino , Microesferas , Tomografia Computadorizada Multidetectores , Tamanho da Partícula , CoelhosRESUMO
PURPOSE: To demonstrate feasibility of developing a noninvasive extracellular pH (pHe ) mapping method on a clinical MRI scanner for molecular imaging of liver cancer. METHODS: In vivo pHe mapping has been demonstrated on preclinical scanners (e.g., 9.4T, 11.7T) with Biosensor Imaging of Redundant Deviation in Shifts (BIRDS), where the pHe readout by 3D chemical shift imaging (CSI) depends on hyperfine shifts emanating from paramagnetic macrocyclic chelates like TmDOTP5- which upon extravasation from blood resides in the extracellular space. We implemented BIRDS-based pHe mapping on a clinical 3T Siemens scanner, where typically diamagnetic 1 H signals are detected using millisecond-long radiofrequency (RF) pulses, and 1 H shifts span over ±10 ppm with long transverse (T2 , 102 ms) and longitudinal (T1 , 103 ms) relaxation times. We modified this 3D-CSI method for ultra-fast acquisition with microsecond-long RF pulses, because even at 3T the paramagnetic 1 H shifts of TmDOTP5- have millisecond-long T2 and T1 and ultra-wide chemical shifts (±200 ppm) as previously observed in ultra-high magnetic fields. RESULTS: We validated BIRDS-based pH in vitro with a pH electrode. We measured pHe in a rabbit model for liver cancer using VX2 tumors, which are highly vascularized and hyperglycolytic. Compared to intratumoral pHe (6.8 ± 0.1; P < 10-9 ) and tumor's edge pHe (6.9 ± 0.1; P < 10-7 ), liver parenchyma pHe was significantly higher (7.2 ± 0.1). Tumor localization was confirmed with histopathological markers of necrosis (hematoxylin and eosin), glucose uptake (glucose transporter 1), and tissue acidosis (lysosome-associated membrane protein 2). CONCLUSION: This work demonstrates feasibility and potential clinical translatability of high-resolution pHe mapping to monitor tumor aggressiveness and therapeutic outcome, all to improve personalized cancer treatment planning.
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Técnicas Biossensoriais , Neoplasias Hepáticas , Animais , Espaço Extracelular , Concentração de Íons de Hidrogênio , Neoplasias Hepáticas/diagnóstico por imagem , Imageamento por Ressonância Magnética , CoelhosRESUMO
Although whole body cooling is used widely to provide therapeutic hypothermia for the brain, there are undesirable clinical side effects. Selective brain cooling may allow for rapid and controllable neuroprotection while mitigating these undesirable side effects. We evaluated an innovative cerebrospinal fluid (CSF) cooling platform that utilizes chilled saline pumped through surgically implanted intraventricular catheters to induce hypothermia. Magnetic resonance thermal imaging of the healthy sheep brain (n = 4) at 7.0T provided dynamic temperature measurements from the whole brain. Global brain temperature was 38.5 ± 0.8°C at baseline (body temperature of 39.2 ± 0.4°C), and decreased by 3.1 ± 0.3°C over â¼30 min of cooling (p < 0.0001). Significant cooling was achieved in all defined regions across both the ipsilateral and contralateral hemispheres relative to catheter placement. On cooling cessation, global brain temperature increased by 3.1 ± 0.2°C over â¼20 min (p < 0.0001). Rapid and synchronized temperature fall/rise on cooling onset/offset was observed reproducibly with rates ranging from 0.06-0.21°C/min, where rewarming was faster than cooling (p < 0.0001) signifying the importance of thermoregulation in the brain. Although core regions (including the subcortex, midbrain, olfactory tract, temporal lobe, occipital lobe, and parahippocampal cortex) had slightly warmer (â¼0.2°C) baseline temperatures, after cooling, temperatures reached the same level as the non-core regions (35.6 ± 0.2°C), indicating the cooling effectiveness of the CSF-based cooling device. In summary, CSF-based intraventricular cooling reliably reduces temperature in all identified brain regions to levels known to be neuroprotective, while maintaining overall systemic normothermia. Dynamic thermal mapping provides high spatiotemporal temperature measurements that can aid in optimizing selective neuroprotective protocols.
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Encéfalo , Hipotermia Induzida/métodos , Infusões Intraventriculares , Solução Salina/administração & dosagem , Termografia/métodos , Animais , Espectroscopia de Ressonância Magnética/métodos , Masculino , Modelos Animais , OvinosRESUMO
PURPOSE: To establish magnetic resonance (MR)-based molecular imaging paradigms for the noninvasive monitoring of extracellular pH (pHe) as a functional surrogate biomarker for metabolic changes induced by locoregional therapy of liver cancer. EXPERIMENTAL DESIGN: Thirty-two VX2 tumor-bearing New Zealand white rabbits underwent longitudinal imaging on clinical 3T-MRI and CT scanners before and up to 2 weeks after complete conventional transarterial chemoembolization (cTACE) using ethiodized oil (lipiodol) and doxorubicin. MR-spectroscopic imaging (MRSI) was employed for pHe mapping. Multiparametric MRI and CT were performed to quantify tumor enhancement, diffusion, and lipiodol coverage of the tumor posttherapy. In addition, incomplete cTACE with reduced chemoembolic doses was applied to mimic undertreatment and exploit pHe mapping to detect viable tumor residuals. Imaging findings were correlated with histopathologic markers indicative of metabolic state (HIF-1α, GLUT-1, and LAMP-2) and viability (proliferating cell nuclear antigen and terminal deoxynucleotidyl-transferase dUTP nick-end labeling). RESULTS: Untreated VX2 tumors demonstrated a significantly lower pHe (6.80 ± 0.09) than liver parenchyma (7.19 ± 0.03, P < 0.001). Upregulation of HIF-1α, GLUT-1, and LAMP-2 confirmed a hyperglycolytic tumor phenotype and acidosis. A gradual tumor pHe increase toward normalization similar to parenchyma was revealed within 2 weeks after complete cTACE, which correlated with decreasing detectability of metabolic markers. In contrast, pHe mapping after incomplete cTACE indicated both acidic viable residuals and increased tumor pHe of treated regions. Multimodal imaging revealed durable tumor devascularization immediately after complete cTACE, gradually increasing necrosis, and sustained lipiodol coverage of the tumor. CONCLUSIONS: MRSI-based pHe mapping can serve as a longitudinal monitoring tool for viable tumors. As most liver tumors are hyperglycolytic creating microenvironmental acidosis, therapy-induced normalization of tumor pHe may be used as a functional biomarker for positive therapeutic outcome.
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Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Biomarcadores Tumorais/análise , Glicólise , Neoplasias Hepáticas Experimentais/patologia , Imagem Molecular/métodos , Microambiente Tumoral , Animais , Doxorrubicina/administração & dosagem , Óleo Etiodado/administração & dosagem , Concentração de Íons de Hidrogênio , Neoplasias Hepáticas Experimentais/diagnóstico por imagem , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Neoplasias Hepáticas Experimentais/metabolismo , Imageamento por Ressonância Magnética/métodos , Masculino , CoelhosRESUMO
This paper describes the design and implementation of elements of an integrated competency-focused pharmacy programme in the School of Pharmacy and Pharmaceutical Sciences (SoPPS), Trinity College Dublin (TCD), Ireland. Following a national review of pharmacy education and training in Ireland in 2010, and subsequent publication of legislation in 2014, the School has implemented a five-year integrated programme of pharmacy education and training, leading to the award of a Master's degree in Pharmacy (M. Pharm.). Curricular integration has been achieved by underpinning the new programme with a national competency framework for pharmacists and through the utilisation of curricular integration themes. Programme integration also encompasses embedded experiential learning placements in Years 2, 4 and 5 of the five-year programme. The new five-year integrated pharmacy programme, which commenced in 2015, replaced the 4 + 1 model of education and training where a four-year Bachelor's degree was followed by a one-year internship, which was a distinct and separate element of the students' training.
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Plant-derived polyphenols are known to have promising biological activities including antioxidant and antityrosinase and may be a potential candidate for anti-dermatoheliotic remedy. The present study was performed to investigate the polyphenolic contents of Mimosa pudica (MP) seed extract and its anti-dermatoheliotic potential using non-invasive biophysical techniques after developing a stable topical emulgel formulation. Moreover, its in-vitro cytotoxicity was also evaluated using normal Human keratinocytes (HaCat cells) to rule out any cellular incompatibility. The results revealed that MP seed extract, constituted with a number of polyphenolic compounds, has very good antioxidant and anti-tyrosinase potential. There were significant positive effects (p ≤ 0.05) invoked by its topical emulgel formulation on various dermatoheliotic associated skin parameters like erythema, melanin, elasticity, hydration, and sebum as compared to placebo. In the meantime, it was also found to be biocompatible and did not show any effect on HaCat cell viability and structure. In conclusion, the topical emulgel preparation loaded with MP seed extract could be a great strategy to deal with dematoheliosis.