Search

Background: 18F-fluciclovine is a synthetic amino acid positron emission tomography (PET) radiotracer that is approved for use in prostate cancer. In this clinical study, we characterised the kinetic model best describing the uptake of 18F-fluciclovine in breast cancer and assessed differences in tracer kinetics and static parameters for different breast cancer receptor subtypes and tumour grades.Methods: Thirty-nine patients with pathologically proven breast cancer underwent 20-min dynamic PET/computed tomography imaging following the administration of 18F-fluciclovine. Uptake into primary breast tumours was evaluated using one- and two-tissue reversible compartmental kinetic models and static parameters.Results: A reversible one-tissue compartment model was shown to best describe tracer uptake in breast cancer. No significant differences were seen in kinetic or static parameters for different tumour receptor subtypes or grades. Kinetic and static parameters showed a good correlation.Conclusions: 18F-fluciclovine has potential in the imaging of primary breast cancer, but kinetic analysis may not have additional value over static measures of tracer uptake.Clinical Trial Registration: NCT03036943. [ABSTRACT FROM AUTHOR]

Poly(lactic acid)/poly(methyl methacrylate) (PLA/PMMA) blends were prepared by melt compounding technique. The miscibility of PLA/PMMA blends at various blending ratios (i.e. 80/20, 60/40, 40/60, and 20/80) was investigated using a dynamic mechanical analyzer (DMA) and solvent uptake experiment. The solvent uptake experiment was conducted to estimate the interaction of PLA/PMMA blends based on the calculation of Flory–Huggins interaction parameter (χ12). DMA results revealed that only single glass transition temperature (Tg) existed along the PLA/PMMA blends. Smallest χ12 (i.e. −0.03) was found on the PLA/PMMA20 blend, suggesting interaction between PLA and PMMA at this composition. The incorporation of PMMA slightly improved the UV protection properties of the PLA/PMMA blend, while maintaining their optical transparency. [ABSTRACT FROM AUTHOR]

We investigated if previously demonstrated inhibition of fluciclovine (18F) in vitro could be replicated in a PC3-Luc xenograft mouse model. Following intratumoral injection of 2-aminobicyclo-(2,2,1)-heptane-2-carboxylic acid (BCH), alpha-(methylamino)isobutyric acid (MeAIB) or saline, fluciclovine PET tumor-to-background activity was 43.6 (± 5.4)% and 25.3 (± 5.2)% lower in BCH (n = 6) and MeAIB (n = 5) injected PC3 Luc xenografts, respectively, compared to saline-injected controls (n = 2). Partial inhibition of fluciclovine uptake by BCH and MeAIB can be demonstrated in vivo similar to previous in vitro modeling. [ABSTRACT FROM AUTHOR]

Purpose: Tumor hypoxia fuels an aggressive tumor phenotype and confers resistance to anticancer treatments. We conducted a clinical trial to determine whether the antimalarial drug atovaquone, a known mitochondrial inhibitor, reduces hypoxia in non-small cell lung cancer (NSCLC)., Patients and Methods: Patients with NSCLC scheduled for surgery were recruited sequentially into two cohorts: cohort 1 received oral atovaquone at the standard clinical dose of 750 mg twice daily, while cohort 2 did not. Primary imaging endpoint was change in tumor hypoxic volume (HV) measured by hypoxia PET-CT. Intercohort comparison of hypoxia gene expression signatures using RNA sequencing from resected tumors was performed., Results: Thirty patients were evaluable for hypoxia PET-CT analysis, 15 per cohort. Median treatment duration was 12 days. Eleven (73.3%) atovaquone-treated patients had meaningful HV reduction, with median change -28% [95% confidence interval (CI), -58.2 to -4.4]. In contrast, median change in untreated patients was +15.5% (95% CI, -6.5 to 35.5). Linear regression estimated the expected mean HV was 55% (95% CI, 24%-74%) lower in cohort 1 compared with cohort 2 ( P = 0.004), adjusting for cohort, tumor volume, and baseline HV. A key pharmacodynamics endpoint was reduction in hypoxia-regulated genes, which were significantly downregulated in atovaquone-treated tumors. Data from multiple additional measures of tumor hypoxia and perfusion are presented. No atovaquone-related adverse events were reported., Conclusions: This is the first clinical evidence that targeting tumor mitochondrial metabolism can reduce hypoxia and produce relevant antitumor effects at the mRNA level. Repurposing atovaquone for this purpose may improve treatment outcomes for NSCLC., (©2021 American Association for Cancer Research.)

Hypodense MCA sign - Large-vessel occlusion secondary to fat embolism post-right hip hemiarthroplasty., (© 2020 The Royal Australian and New Zealand College of Radiologists.)

The aim of this guideline is to provide standards for the recommendation, performance, interpretation, and reporting of [ 18 F]Fluciclovine PET/CT for prostate cancer imaging. These recommendations will help to improve accuracy, precision, and repeatability of [ 18 F]Fluciclovine PET/CT for prostate cancer essentially needed for implementation of this modality in science and routine clinical practice.

Background: Mobile health applications (mHealth apps) are increasingly being used to perform tasks that are conventionally performed by general practitioners (GPs), such as those involved in promoting health, preventing disease, diagnosis, treatment, monitoring, and support for health services. This raises an important question: can mobile apps replace GPs? This study aimed to systematically search for and identify mobile apps that can perform GP tasks., Methods: A scoping review was carried out. The Google Play Store and Apple App Store were searched for mobile apps, using search terms derived from the UK Royal College of General Practitioners (RCGP) guideline on GPs' core capabilities and competencies. A manual search was also performed to identify additional apps., Results: The final analysis included 17 apps from the Google Play Store and Apple App Store, and 21 apps identified by the manual search. mHealth apps were found to have the potential to replace GPs for tasks such as recording medical history and making diagnoses; performing some physical examinations; supporting clinical decision making and management; assisting in urgent, long-term, and disease-specific care; and health promotion. In contrast, mHealth apps were unable to perform medical procedures, appropriately utilise other professionals, and coordinate a team-based approach., Conclusions: This scoping review highlights the functions of mHealth apps that can potentially replace GP tasks. Future research should focus on assessing the performance and quality of mHealth apps in comparison with that of real doctors.

Anti-AMPA (anti-α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid) receptor limbic encephalitis is a rare autoimmune syndrome. It can be associated with an underlying malignancy, such as lung, breast, or thymus. We are reporting a case of a 19-year-old patient who presented with a 2-week history of confusion and short-term memory loss. A magnetic resonance imaging of brain showed increased T2 hyperintensity within the hippocampi bilaterally. Cerebrospinal fluid analysis was positive for anti-AMPA receptor antibodies. A computed tomography revealed multiple pulmonary metastases as well as an expansile lucent and sclerotic lesion in the ilium, which was subsequently biopsied. Histopathology confirmed a diagnosis of Ewing sarcoma (ES). Fluorescence in situ hybridization testing of the specimen identified EWSR1 (22q12.2) signal rearrangements in 80% of cells scored. To date, this is the first case report describing anti-AMPA receptor limbic/paraneoplastic encephalitis as a presenting feature of ES. Although it is rare, the possibility of ES may be considered in young patients presenting with anti-AMPA receptor limbic encephalitis.

Tapentadol is a centrally acting synthetic analgesic which is prescribed for the treatment of a range of chronic pain conditions. Its use in treating various pain conditions is increasing and, as with other opioids, it has the potential to be abused. We describe a three-stage incorporation of tapentadol into validated screening and quantitative methods through: (i) addition of retention time/mass spectral data to a database, (ii) qualitative validation and (iii) quantitative validation. This represents an efficient and flexible approach to the incorporation of new compounds of interest to existing screening methods. Tapentadol was analyzed in blood and serum samples using alkaline liquid-liquid extraction with identification and quantitation by liquid chromatography/time-of-flight mass spectrometry. In a series of six post-mortem cases where tapentadol was detected but was not a primary causative factor in death, blood concentrations ranged from 0.01 to 1.0 mg/L. In two cases where tapentadol was a significant contributor to death, post-mortem blood concentrations were 1.7 and 3.9 mg/L. In one of these fatal cases, ante-mortem blood and serum were also analyzed. The tapentadol concentration in the post-mortem blood was 30% higher than in the ante-mortem blood after a post-mortem interval of 13 days, indicating some potential for post-mortem redistribution. The measured ante-mortem blood:serum ratio was 1.7, and is the first such ratio to be reported. Other drugs were detected in almost all cases, with the majority being prescription analgesics, sedatives and antidepressants. The number of cases in which tapentadol has been detected has increased in recent years, highlighting the importance of screening for this drug in forensic toxicological laboratories.

Purpose: To investigate if the presence of systemic inflammatory response syndrome (SIRS) in patients with urinary tract obstruction at time of presentation to the emergency department correlates with a subsequent positive urine culture and to determine if it could be used as a tool to predict the urgency of a percutaneous nephrostomy (PCN). The secondary aim of the study was to assess the incidence of in-hour and after-hour emergent PCNs performed in a tertiary center which has both interventional radiological and urological expertise., Methods and Materials: Emergent adult PCN cases referred from the emergency department between 2011 and 2016 were identified retrospectively. Urine culture results, clinical features of SIRS, timing of procedure, and radiological findings were analyzed., Results: A total of 110 patients met the inclusion criteria. There were a total of 60 male and 50 female patients with a mean age of 62 (age range 18-99 years). Ninety-two (83%) PCN patients were referred and performed on after-hours with the remaining 18 patients performed in-hours. There were 53 (48%) patients that met the criteria for obstruction with SIRS and 57 (52%) patients with obstruction without SIRS. The number of after-hours PCN performed in both groups was equal at 46 patients each. The most common cause of obstruction in the SIRS group was stone related in 31 (58%) patients. Whereas, the most common cause of obstruction in the non-SIRS group was due to malignancy in 26 (45%) cases. An elevated temperature and heart rate were the most common features of SIRS at 96 and 83% respectively in the SIRS group. An organism was isolated in 35 (67%) out of the 52 urine culture results obtained for the SIRS group. No organism was isolated in 42 (95%) out of the 44 urine culture results obtained in the non-SIRS group. Statistical analysis using Fisher's test revealed that the association between obstruction without SIRS and a negative urine culture result was statistically significant (p < 0.0001)., Conclusion: A large percentage (50%) of PCN cases performed after-hours could have been performed during daytime hours instead due to the absence of infection. This would be in line with the practices of some centers that consider an infected obstructed kidney as the only absolute indication for emergent decompression overnight. The study also demonstrates that the absence of a SIRS in a patient with urinary tract obstruction correlates well with a negative urine culture result from the nephrostomy specimen which has a high negative predictive value for excluding pyonephrosis.

Introduction: Children who develop any hypersensitivity reaction to eggs are routinely referred to hospital for Measles-Mumps-Rubella (MMR) vaccination as inpatients to prevent anaphylaxis. We aimed to study the association between hypersensitivity reactions after egg exposure and similar reactions after MMR immunisation; and examine the necessity of hospital admission for vaccination., Methods: A prospective observational study was conducted in Paediatric Department in Bukit Mertajam Hospital, Penang, between March and December 2014. Children referred from local polyclinics for inpatient MMR vaccination because of a history of egg allergy were recruited. The children were observed in the ward for post vaccination allergic reactions. Concurrently, a group of children without egg allergy was recruited from those admitted for other illnesses but had recent MMR vaccination at polyclinics. Parents of these children were interviewed and asked if they had observed any reactions post vaccination. In both groups, sociodemographics, medical history and family history of atopy were collected., Results: Eighty-seven subjects were recruited in this study. Fifty-four infants with egg allergy had previous mild allergic reactions after exposure to eggs or egg-related products. They were associated with a family history of egg hypersensitivity, personal history of acute gastroenteritis and upper respiratory tract infections. Two of them developed cutaneous rashes post vaccination during observation, but none developed anaphylactic or anaphylactoid reactions. Two infants among those without egg allergy had post vaccination fever. There was no association between egg allergy and hypersensitivity reactions to MMR vaccine (p=0.632)., Conclusions: MMR vaccine can be safely administered to children with mild egg allergy, hence admission for vaccination in the hospital is not warranted. Risk stratification is required to ensure only infants with severe reactions will be admitted for vaccination.