Publications by authors named "Wanek T"

Purpose Of The Study: The annual number of spinal fusion procedures has been increasing and is well documented worldwide. The O-arm is slowly becoming the standard for transpedicular screw insertion. The accuracy and safety of this method have been confirmed by many studies.

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Since the discovery of cisplatin's antitumoral activity and its approval as an anticancer drug, significant efforts have been made to enhance its physiological stability and anticancer efficacy and to reduce its side effects. With the rapid development of targeted and personalized therapies, and the promising theranostic approach, platinum drugs have found new opportunities in more sophisticated systems. Theranostic agents combine diagnostic and therapeutic moieties in one scaffold, enabling simultaneous disease monitoring, therapy delivery, response tracking, and treatment efficacy evaluation.

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Cholangiocarcinoma (CCA) is a type of primary liver cancer originating from the biliary tract epithelium, characterized by limited treatment options for advanced cases and low survival rates. This study aimed to establish an orthotopic mouse model for CCA and monitor tumor growth using PET/MR imaging. Murine CCA cells were implanted into the liver lobe of male C57BL/6J mice.

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Purpose: Preclinical imaging, with translational potential, lacks a standardized method for defining volumes of interest (VOIs), impacting data reproducibility. The aim of this study was to determine the interobserver variability of VOI sizes and standard uptake values (SUV and SUV) of different organs using the same [F]FDG-PET and PET/CT datasets analyzed by multiple observers. In addition, the effect of a standardized analysis approach was evaluated.

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Nanodiamonds (NDs) are emerging as a novel nanoparticle class with growing interest in medical applications. The surface coating of NDs can be modified by attaching binding ligands or imaging probes, turning them into multi-modal targeting agents. In this investigation, we assessed the targeting efficacy of octreotide-functionalized Ga-radiolabelled NDs for cancer imaging and compared it with the tumor uptake using [Ga]Ga-DOTA-TOC.

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P-glycoprotein (P-gp, encoded in humans by the gene and in rodents by the genes) is a membrane transporter that can restrict the intestinal absorption and tissue distribution of many drugs and may also contribute to renal and hepatobiliary drug excretion. The aim of this study was to compare the performance and sensitivity of currently available radiolabeled P-gp substrates for positron emission tomography (PET) with the single-photon emission computed tomography (SPECT) radiotracer [Tc]Tc-sestamibi for measuring the P-gp function in the kidneys and liver. Wild-type, heterozygous (), and homozygous () knockout mice were used as models of different P-gp abundance in excretory organs.

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The efflux transporter P-glycoprotein (P-gp) at the blood-brain barrier limits the cerebral uptake of various xenobiotics. To assess the sensitivity of [C]metoclopramide to measure decreased cerebral P-gp function, we performed [C]metoclopramide PET scans without (baseline) and with partial P-gp inhibition by tariquidar in wild-type, heterozygous and homozygous mice as models with controlled levels of cerebral P-gp expression. Brains were collected to quantify P-gp expression with immunohistochemistry.

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PURPOSE OF THE STUDY Tranexamic acid as a haemostatic agent is commonly used in multiple medical branches. Over the last decade, there has been a steep rise in the number of studies evaluating its effect, i.e.

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Transporter-mediated drug-drug interactions (DDIs) are of concern in antimicrobial drug development, as they can have serious safety consequences. We used positron emission tomography (PET) imaging-based pharmacokinetic (PK) analysis to assess the effect of different drugs, which may cause transporter-mediated DDIs, on the tissue distribution and excretion of [F]ciprofloxacin as a radiolabeled model antimicrobial drug. Mice underwent PET scans after intravenous injection of [F]ciprofloxacin, without and with pretreatment with either probenecid (150 mg/kg), cimetidine (50 mg/kg), or pyrimethamine (5 mg/kg).

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In the lungs, the membrane transporter P-glycoprotein (P-gp) is expressed in the apical (i.e. lumen-facing) membrane of airway epithelial cells and in the luminal (blood-facing) membrane of pulmonary capillary endothelial cells.

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Purpose: Nanodiamonds (NDs) represent a new class of nanoparticles and have gained increasing interest in medical applications. Modifying the surface coating by attaching binding ligands or imaging probes can transform NDs into multi-modal targeting probes. This study evaluated the biokinetics and biodistribution of Ga-radiolabelled NDs in a xenograft model.

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Colorectal cancer is one of the leading causes of cancer-related deaths worldwide. Increased expression of CXCR4 has been associated with liver metastasis, disease progression, and shortened survival. Using in vitro cell binding studies and the in ovo model, we aimed to investigate the potential of [Ga]Ga-Pentixafor, a radiotracer specifically targeting human CXCR4, for CRC imaging.

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P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP) are two efflux transporters which are expressed in the apical (i.e. airway lumen-facing) membranes of lung epithelial cells.

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Multidrug resistance-associated protein 1 (MRP1, encoded by the gene) may contribute to the clearance of amyloid-beta (Aβ) peptides from the brain into the blood and stimulation of MRP1 transport activity may be a therapeutic approach to enhance brain Aβ clearance. In this study, we assessed the effect of thiethylperazine, an antiemetic drug which was shown to stimulate MRP1 activity in vitro and to decrease Aβ load in a rapid β-amyloidosis mouse model (APP/PS1-21), on MRP1 transport activity by means of positron emission tomography (PET) imaging with the MRP1 tracer 6-bromo-7-[C]methylpurine. Groups of wild-type, APP/PS1-21 and mice underwent PET scans before and after a 5-day oral treatment period with thiethylperazine (15 mg/kg, once daily).

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Coccygodynia, or tailbone pain, is the most common in women after trauma (complicated childbirth, fall). This pain can be treated conservatively (by using analgesics, local injections, physiotherapy) or by surgical coccygectomy. In the presented article, a set of five female patients is evaluated, in whom, after the failing conservative therapy, coccygectomy was indicated for persistent coccygodynia.

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Article Synopsis
  • Several inhaled drugs for pulmonary diseases are influenced by the P-glycoprotein (P-gp) transporter, which can affect how these drugs are absorbed and distributed in the lungs.
  • A new experimental approach utilizing positron emission tomography (PET) was developed to study the impact of P-gp on drug delivery in rats, observing how it influences drug exposure in the lungs.
  • Results indicate that inhibiting P-gp function reduces lung exposure to certain drugs, potentially lowering their effectiveness, thus showing the utility of PET imaging to explore how transporters affect drug delivery in both animals and humans.
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Background: To better understand the etiology and pathomechanisms of Alzheimer's disease, several transgenic animal models that overexpress human tau or human amyloid-beta (Aβ) have been developed. In the present study, we generated a novel transgenic rat model by cross-breeding amyloid precursor protein (APP) rats with tau rats. We characterized this model by performing positron emission tomography scans combined with immunofluorescent labeling and cerebrospinal fluid analyses.

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P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP) are co-localized at the blood-brain barrier, where they display functional redundancy to restrict the brain distribution of dual P-gp/BCRP substrate drugs. We used positron emission tomography (PET) with the metabolically stable P-gp/BCRP substrates [C]tariquidar, [C]erlotinib, and [C]elacridar to assess whether a similar functional redundancy as at the BBB exists in the liver, where both transporters mediate the biliary excretion of drugs. Wild-type, , , and mice underwent dynamic whole-body PET scans after i.

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Article Synopsis
  • Ciprofloxacin is an antibiotic that is removed from the body by being emptied out through the kidneys and intestines.
  • Scientists used special imaging (PET scans) to study how certain proteins affect how ciprofloxacin is cleared from the body in mice.
  • Their findings suggest that multiple transporters help in getting rid of ciprofloxacin, which means there could be other ways the body manages this antibiotic that scientists didn't expect.
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The development of highly selective and fast biocompatible reactions for ligation and cleavage has paved the way for new diagnostic and therapeutic applications of pretargeted chemistry. The concept of bioorthogonal pretargeting has attracted considerable interest, in particular for the targeted delivery of radionuclides and drugs. In nuclear medicine, pretargeting can provide increased target-to-background ratios at early time-points compared to traditional approaches.

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PURPOSE OF THE STUDY Sacroiliac joint dysfunction is defined as a permanent chronic pain originating from the sacroiliac joint, limiting the patient's daily activities. The purpose of this study was to evaluate the effectiveness of the minimally invasive sacroiliac joint stabilization by triangular titanium implants in patients with sacroiliac joint dysfunction. MATERIAL AND METHODS The prospective study evaluated the patients who had underwent a minimally invasive sacroiliac joint stabilization for sacroiliac joint dysfunction with the use of iFuse® implants.

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In imaging, penetration depth comes at the expense of lateral resolution, which restricts the scope of 3D in-vivo imaging of small animals at micrometer resolution. Bioimaging will need to expand beyond correlative light and electron microscopy (CLEM) approaches to combine insights about in-vivo dynamics in a physiologically relevant 3D environment with ex-vivo information at micrometer resolution (or beyond) within the spatial, structural and biochemical contexts. Our report demonstrates the immense potential for biomedical discovery and diagnosis made available by bridging preclinical in-vivo imaging with ex-vivo biological microscopy to zoom in from the whole organism to individual structures and by adding localized spectroscopic information to structural and functional information.

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Purpose: To investigate the role of cation transporters (OCTs, MATEs) in the renal and hepatic disposition of the radiolabeled antiemetic drug [C]metoclopramide in mice with PET.

Methods: PET was performed in wild-type mice after administration of an intravenous microdose (<1 μg) of [C]metoclopramide without and with co-administration of either unlabeled metoclopramide (5 or 10 mg/kg) or the prototypical cation transporter inhibitors cimetidine (150 mg/kg) or sulpiride (25 mg/kg). [C]Metoclopramide PET was also performed in wild-type and Slc22a1/2 mice.

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Background: ABCB1 (P-glycoprotein) and ABCG2 (breast cancer resistance protein) are co-localized at the blood-brain barrier (BBB), where they restrict the brain distribution of many different drugs. Moreover, ABCB1 and possibly ABCG2 play a role in Alzheimer's disease (AD) by mediating the brain clearance of beta-amyloid (Aβ) across the BBB. This study aimed to compare the abundance and activity of ABCG2 in a commonly used β-amyloidosis mouse model (APP/PS1-21) with age-matched wild-type mice.

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P-glycoprotein (ABCB1) and breast cancer resistance protein (ABCG2) restrict at the blood-brain barrier (BBB) the brain distribution of the majority of currently known molecularly targeted anticancer drugs. To improve brain delivery of dual ABCB1/ABCG2 substrates, both ABCB1 and ABCG2 need to be inhibited simultaneously at the BBB. We examined the feasibility of simultaneous ABCB1/ABCG2 inhibition with i.

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