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UNASSIGNED: Infective endocarditis is a challenging diagnosis that usually requires cardiovascular image confirmation as part of the approach. 18F-Fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG-PET/CT) is an imaging technique more sensible for the diagnosis of prosthetic valve endocarditis (PVE) when echocardiography is inconclusive.
UNASSIGNED: We present the case of a 35-year-old man who had a previous Bentall-De Bono procedure 4 years prior that included biological, national institute of cardiology (INC)-type, locally manufactured aortic valve replacement and woven Dacron tube graft implantation in the ascending aorta. He was admitted because of dyspnoea, oedema, fever, and syncope. A complete auriculoventricular blockade was diagnosed, requiring cardiac pacing. Also, infective endocarditis (IE) was suspected. Blood cultures showed the isolation of Bacillus licheniformis. Transthoracic echocardiography, transoesophageal echocardiography, and CT angiography were inconclusive for IE. Treatment was initiated with intravenous (IV) antibiotic therapy, and an extensive protocol for IE, including molecular imaging modalities, was ordered. 99mTc-Ubiquicidin scintigraphy was acquired without abnormal findings. Images of 18F-FDG-PET/CT revealed abnormally intense heterogeneous uptake in the prosthetic aortic annulus in a classic pattern. Applying the modified 2015 Duke criteria for PET/CT, PVE was confirmed.
UNASSIGNED: Although the other imaging modalities were negative, the high clinical suspicion made it mandatory to continue the study protocol, remarking on the utility of 18F-FDG-PET/CT on patients categorized as having \'possible\' endocarditis, as in our patient.

This article enthusiastically explores the study of highly aggressive variant prostate cancer (AVPC), acknowledging its relatively rare yet highly menacing presence within the realm of prostate cancer. The paper delves into the pathological characteristics of AVPC, diagnostic and therapeutic challenges, and the potential applications of precision medicine and molecular imaging in the future.

Epithelial ovarian and fallopian cancers are aggressive lesions that rarely metastasize to the central nervous system. Brain metastases usually occur in the setting of known primary disease or widespread metastatic disease. However, in extremely rare cases, an isolated intracranial neoplasm may be the first presentation of fallopian cancer. To the best of our knowledge, only one such case has been reported previously. We present an illustrative case with multimodality imaging and histopathologic correlation of a fallopian tube carcinoma first presenting with altered mental status secondary to an isolated brain metastasis. A 64-year-old female with no pertinent medical history presented with altered mentation. Initial workup identified a 1.6 cm avidly enhancing, solitary brain lesion at the gray-white junction with associated vasogenic edema concerning for either central nervous system lymphoma or metastatic disease. Additional imaging identified a 7.5 × 3 cm left adnexal lesion, initially thought to be a hydrosalpinx with hemorrhage, but magnetic resonance imaging suggested gynecologic malignancy. No lesions elsewhere in the body were identified. Given the lack of locoregional or systemic disease, the intracranial and pelvic lesions were assumed to represent synchronous but distinct processes. The intracranial lesion was biopsied. Preliminary results were suggestive of lymphoma, but further analysis was consistent with high-grade serous carcinoma of müllerian origin. Positron emission tomography/computed tomography was performed to evaluate for other neoplastic lesions, only highlighting the intracranial and pelvic lesions. At this point, a diagnosis of metastatic fallopian cancer was made. The patient was taken for robot-assisted laparoscopy with surgical debulking of the pelvic neoplasm, pathology demonstrating high-grade serous carcinoma of the fallopian tube, matching that of the intracranial lesion. Even though rare, metastatic fallopian cancer should be considered in patients with isolated brain lesions and adnexal lesions, even in the absence of locoregional or systemic disease.

Mixing states of aerosol particles are crucial for understanding the role of aerosols in influencing air quality and climate. However, a fundamental understanding of the complex mixing states is still lacking because most traditional analysis techniques only reveal bulk chemical and physical properties with limited surface and 3-D information. In this research, 3-D molecular imaging enabled by ToF-SIMS was used to elucidate the mixing states of PM2.5 samples obtained from a typical Beijing winter haze event. In light pollution cases, a thin organic layer covers separated inorganic particles; while in serious pollution cases, ion exchange and an organic-inorganic mixing surface on large-area particles were observed. The new results provide key 3-D molecular information of mixing states, which is highly potential for reducing uncertainty and bias in representing aerosol-cloud interactions in current Earth System Models and improving the understanding of aerosols on air quality and human health.

BACKGROUND: The management of radioiodine refractory differentiated thyroid cancer (RAIR-DTC) represents a major challenge in thyroid cancer. The American Thyroid Association guidelines recommend the use of tyrosine kinase inhibitors (TKIs) for RAIR-DTC that does not respond to conventional treatment. Currently, imaging modalities that predict the response to TKI treatment based on morphological and functional features are lacking. we report a case of a patient with progressive RAIR lung metastases who underwent 2-deoxy-2-[ 18 F]fluoro-D-glucose and 99technetiumm-three polyethylene glycol spacers-arginine-glycine-aspartic acid ( 99 Tc m -3PRGD 2 ) dual-tracer imaging and investigate the value of this imaging strategy for determining subsequent therapeutic schedules.
METHODS: A 52-year-old man with advanced RAIR-DTC and progressive lung metastasis. After TKI treatment [sorafenib] lost its clinical benefits, the patient\'s therapeutic response was evaluated as progressive disease. 2-deoxy-2-[ 18 F]fluoro-D-glucose PET/CT and 99 Tc m -3PRGD 2 SPECT/CT were performed. There were multiple FDG-positive lesions in the lung. However, 99 Tc m -3PRGD 2 SPECT/CT showed only 1 lesion in the right middle pulmonary lobe with arginine-glycine-aspartic positivity.
METHODS: RAIR-DTC.
METHODS: Radiofrequency ablation was performed for only the lesion with RDG and FDG positivity.
RESULTS: The patient quickly achieved partial response.
CONCLUSIONS: This case indicates that for progressive RAIR metastases, patients can benefit more from prioritizing treatment for lesions that are both arginine-glycine-aspartic and FDG positive.

18F-FDG PET plays a major role in the pre-surgical evaluation of medically refractory epilepsy patients. The current standard of care is performing interictal evaluations of glucose metabolism. This is mostly related to the tracer kinetics of 18F-FDG owing to a long uptake phase which would translate into ictal injections having low sensitivities and low specificity and demonstrating not only ictal but post-ictal changes. It has been reported that this limitation can be overcome in some status epilepticus scenarios where prolonged seizures can then correlate better with 18F-FDG uptake kinetics. In these cases, focal visual qualitative hot spots are suggestive of the seizure onset zone (SOZ). However, we note that by using advanced subtraction techniques, the prolonged 18F-FDG uptake phase can be overcome in a variety of other cases as well. This opens the door to a slightly larger set of patients that may benefit from this higher resolution PET method. We present 4 cases where a novel subtraction 18F-FDG PET technique was used and elucidate its impact in these specific cases.

Human hair absorbs numerous biomolecules from the body during its growth. This can act as a fingerprint to determine substance intake of an individual, which can be useful in forensic studies. The cocaine concentration profile along the growth axis of hair indicates the time evolution of the metabolic incorporation of cocaine usage. It could be either assessed by chemical extraction and further analysis of hair bundels, or by direct single hair fibre analysis with mass spectroscopy imaging (MSI). Within this work, we analyzed the cocaine distribution in individual hair samples using MeV-SIMS. Unlike conventional surface analysis methods, we demonstrate high yields of nonfragmented molecular ions from the surface of biological materials, resulting in high chemical sensitivity and non-destructive characterisation. Hair samples were prepared by longitudinally cutting along the axis of growth, leaving half-cylindrical shape to access the interior structure of the hair by the probing ion beam, and attached to the silicon wafer. A focused 5.8 MeV 35Cl6+ beam was scanned across the intact, chemically pristine hair structure. A non-fragmented protonated [M+ H]+ cocaine molecular peak at m/z = 304 was detected and localized along the cross-section of the hair. Its intensity exhibits strong fluctuations along the direction of the hair\'s growth, with pronounced peaks as narrow as 50 micrometres, corresponding to a metabolic incorporation time of approx. three hours.

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The molecular imaging of apoptosis remains an important method for the diagnosis and monitoring of the progression of certain diseases and the evaluation of the efficacy of anticancer apoptosis-inducing therapies. Among the multiple biomarkers involved in apoptosis, activated caspase-3 is an attractive target, as it is the most abundant of the executioner caspases. Nuclear imaging is a good candidate, as it combines a high depth of tissue penetration and high sensitivity, features necessary to detect small changes in levels of apoptosis. However, designing a caspase-3 radiotracer comes with challenges, such as selectivity, cell permeability and transient caspase-3 activation. In this review, we discuss the different caspase-3 radiotracers for the imaging of apoptosis together with the challenges of the translation of various apoptosis-imaging strategies in clinical trials.