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Photosynthetic dinoflagellates play crucial roles in global primary production and carbon fixation. Despite their success in filling various ecological niches, numerous mysteries about their plastid evolution and plastid genomes remain unsolved. The plastid genome of dinoflagellates presents one of the most complex lineages in the biological realm, mainly due to multiple endosymbiotic plastid events in their evolutionary history. Peridinin-containing dinoflagellates possess the most reduced and fragmented genome, with only a few genes located on multiple "minicircles", whereas replacement plastids in dinoflagellate lineages have undergone different degrees of endosymbiotic gene transfer. Recent advancements in high-throughput sequencing have improved our understanding of plastid genomes and plastid-encoded gene expression in many dinoflagellate species. Plastid transcripts of dinoflagellates exhibit two unconventional processing pathways: the addition of a 3' poly(U) tail and substitutional RNA editing. These pathways are widely employed across dinoflagellate lineages, which are possibly retained from the ancestral peridinin plastid. This mini-review summarizes the developments in the plastid genomes of dinoflagellates and pinpoints the research areas that necessitate further exploration, aiming to provide valuable insights into plastid evolution in these fascinating and important organisms.
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Dinoflagellida , Genome, Plastid , Dinoflagellida/genetics , Plastids/genetics , Symbiosis/genetics , Evolution, Molecular , RNA Editing , PhylogenyABSTRACT
The widespread use of neck US and other imaging modalities has contributed to a phenomenon of increased detection of differentiated thyroid cancer (DTC). Most of these cancers remain indolent, without requiring surgical intervention. Nonetheless, a subset of patients who require surgical treatment experience subsequent disease recurrence. This most commonly occurs in the cervical lymph nodes and thyroid bed, followed by distant metastasis to the lungs and bones. Because imaging is an integral part of postoperative surveillance, radiologists play a central role in the detection of recurrent tumors and in guiding treatment in these patients. US is the primary imaging modality used for postoperative evaluation. Other modalities such as CT, MRI, radioactive iodine imaging, and PET/CT aid in the accurate diagnosis and characterization of recurrent disease. Therefore, radiologists must have a thorough understanding of the utility of these imaging techniques and the imaging characteristics of recurrent DTC when interpreting these multimodality studies. The interpretation of imaging findings should also be correlated with the clinical status of patients and their biochemical markers to minimize interpretative errors. The authors present a broad overview of the postoperative evaluation of DTC, including its initial primary management, staging, and prognostication; clinical risk stratification for recurrent disease; postoperative surveillance with imaging and evaluation of biochemical markers; and management of recurrent DTC. Published under a CC BY 4.0 license. Supplemental material is available for this article.
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Neoplasm Recurrence, Local , Thyroid Neoplasms , Thyroidectomy , Humans , Thyroid Neoplasms/diagnostic imaging , Thyroid Neoplasms/surgery , Thyroid Neoplasms/pathology , Neoplasm Recurrence, Local/diagnostic imaging , Neoplasm Staging , Diagnostic Imaging/methodsABSTRACT
Harmful algal blooms (HABs) are a global environmental concern, causing significant economic losses in fisheries and posing risks to human health. Algicidal bacteria have been suggested as a potential solution to control HABs, but their algicidal efficacy is influenced by various factors. This study aimed to characterize a novel algicidal bacterium, Maribacter dokdonensis (P4), isolated from a Karenia mikimotoi (Hong Kong strain, KMHK) HAB and assess the impact of P4 and KMHK's doses, growth phase, and algicidal mode and the axenicity of KMHK on P4's algicidal effect. Our results demonstrated that the algicidal effect of P4 was dose-dependent, with the highest efficacy at a dose of 25% v/v. The study also determined that P4's algicidal effect was indirect, with the P4 culture and the supernatant, but not the bacterial cells, showing significant effects. The algicidal efficacy was higher when both P4 and KMHK were in the stationary phase. Furthermore, the P4 culture at the log phase could effectively kill KMHK cells at the stationary phase, with higher algicidal efficacy in the bacterial culture than that of the supernatant alone. Interestingly, P4's algicidal efficacy was significantly higher when co-culturing with xenic KMHK (~90% efficacy at day 1) than that with the axenic KMHK (~50% efficacy at day 1), suggesting the presence of other bacteria could regulate P4's algicidal effect. The bacterial strain P4 also exhibited remarkable algicidal efficacy on four other dinoflagellate species, particularly the armored species. These results provide valuable insights into the algicidal effect of M. dokdonensis on K. mikimotoi and on their interactions.
Subject(s)
Dinoflagellida , Flavobacteriaceae , Water , Humans , Dinoflagellida/physiology , Harmful Algal Bloom , BacteriaABSTRACT
OBJECTIVE: To investigate the validity and test-retest reliability of a customized markerless motion capture (MMC) system that used iPad Pros with a Light Detection And Ranging scanner at two different viewing angles to measure the active range of motion (AROM) and the angular waveform of the upper-limb-joint angles of healthy adults performing functional tasks. DESIGN: Participants were asked to perform shoulder and elbow actions for the investigator to take AROM measurements, followed by four tasks that simulated daily functioning. Each participant attended 2 experimental sessions, which were held at least 2 days and at most 14 days apart. SETTING: A Vicon system and 2 iPad Pros installed with our MMC system were placed at 2 different angles to the participants and recorded their movements concurrently during each task. PARTICIPANTS: Thirty healthy adults (mean age: 28.9, M/F ratio: 40/60). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: The AROM and the angular waveform of the upper-limb-joint angles. RESULTS: The iPad Pro MMC system underestimated the shoulder joint and elbow joint angles in all four simulated functional tasks. The MMC demonstrated good to excellent test-retest reliability for the shoulder joint AROM measurements in all 4 tasks. CONCLUSIONS: The maximal AROM measurements calculated by the MMC system had consistently smaller values than those measured by the goniometer. An MMC in iPad Pro system might not be able to replace conventional goniometry for clinical ROM measurements, but it is still suggested for use in home-based and telerehabilitation training for intra-subject measurements because of its good reliability, low cost, and portability. Further development to improve its performance in motion capture and analysis in disease populations is warranted.
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Motion Capture , Upper Extremity , Adult , Humans , Pilot Projects , Biomechanical Phenomena , Reproducibility of Results , Range of Motion, ArticularABSTRACT
BACKGROUND: Markerless motion capture (MMC) technology has been developed to avoid the need for body marker placement during motion tracking and analysis of human movement. Although researchers have long proposed the use of MMC technology in clinical measurement-identification and measurement of movement kinematics in a clinical population, its actual application is still in its preliminary stages. The benefits of MMC technology are also inconclusive with regard to its use in assessing patients' conditions. In this review we put a minor focus on the method's engineering components and sought primarily to determine the current application of MMC as a clinical measurement tool in rehabilitation. METHODS: A systematic computerized literature search was conducted in PubMed, Medline, CINAHL, CENTRAL, EMBASE, and IEEE. The search keywords used in each database were "Markerless Motion Capture OR Motion Capture OR Motion Capture Technology OR Markerless Motion Capture Technology OR Computer Vision OR Video-based OR Pose Estimation AND Assessment OR Clinical Assessment OR Clinical Measurement OR Assess." Only peer-reviewed articles that applied MMC technology for clinical measurement were included. The last search took place on March 6, 2023. Details regarding the application of MMC technology for different types of patients and body parts, as well as the assessment results, were summarized. RESULTS: A total of 65 studies were included. The MMC systems used for measurement were most frequently used to identify symptoms or to detect differences in movement patterns between disease populations and their healthy counterparts. Patients with Parkinson's disease (PD) who demonstrated obvious and well-defined physical signs were the largest patient group to which MMC assessment had been applied. Microsoft Kinect was the most frequently used MMC system, although there was a recent trend of motion analysis using video captured with a smartphone camera. CONCLUSIONS: This review explored the current uses of MMC technology for clinical measurement. MMC technology has the potential to be used as an assessment tool as well as to assist in the detection and identification of symptoms, which might further contribute to the use of an artificial intelligence method for early screening for diseases. Further studies are warranted to develop and integrate MMC system in a platform that can be user-friendly and accurately analyzed by clinicians to extend the use of MMC technology in the disease populations.
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Artificial Intelligence , Motion Capture , Humans , Movement , Motion , Biomechanical Phenomena , TechnologyABSTRACT
Quantitative nuclear imaging techniques are in high demand for various disease diagnostics and cancer theranostics. The non-invasive imaging modality requires radiotracing through the radioactive decay emission of the radionuclide. Current preclinical and clinical radiotracers, so-called nuclear imaging probes, are radioisotope-labeled small molecules. Liposomal radiotracers have been rapidly developing as novel nuclear imaging probes. The physicochemical properties and structural characteristics of liposomes have been elucidated to address their long circulation and stability as radiopharmaceuticals. Various radiolabeling methods for synthesizing radionuclides onto liposomes and synthesis strategies have been summarized to render them biocompatible and enable specific targeting. Through a variety of radionuclide labeling methods, radiolabeled liposomes for use as nuclear imaging probes can be obtained for in vivo biodistribution and specific targeting studies. The advantages of radiolabeled liposomes including their use as potential clinical nuclear imaging probes have been highlighted. This review is a comprehensive overview of all recently published liposomal SPECT and PET imaging probes.
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Liposomes , Radioisotopes , Liposomes/chemistry , Tissue Distribution , Tomography, Emission-Computed, Single-Photon/methods , Positron-Emission Tomography/methods , Radiopharmaceuticals/chemistryABSTRACT
Karenia mikimotoi is a well-known harmful algal bloom species. Blooms of this dinoflagellate have become a serious threat to marine life, including fish, shellfish, and zooplanktons and are usually associated with massive fish death. Despite the discovery of several toxins such as gymnocins and gymnodimines in K. mikimotoi, the mechanisms underlying the ichthyotoxicity of this species remain unclear, and molecular studies on this topic have never been reported. The present study investigates the fish-killing mechanisms of K. mikimotoi through comparative proteomic analysis. Marine medaka, a model fish organism, was exposed to K. mikimotoi for a three-part time period (LT25, LT50 and LT90). Proteins extracted from the whole fish were separated by using two-dimensional gel electrophoresis, and differentially expressed proteins were identified with reference to an untreated control. The change in fish proteomes over the time-course of exposure were analyzed. A total of 35 differential protein spots covering 19 different proteins were identified, of which most began to show significant change in expression levels at the earliest stage of intoxication. Among the 19 identified proteins, some are closely related to the oxidative stress responses, energy metabolism, and muscle contraction. We propose that oxidative stress-mediated muscle damage might explain the symptoms developed during the ichthyotoxicity test, such as gasping for breath, loss of balance, and body twitching. Our findings lay the foundations for more in-depth studies of the mechanisms of K. mikimotoi's ichthyotoxicity.
Subject(s)
Dinoflagellida/pathogenicity , Fishes/metabolism , Fishes/parasitology , Proteome/metabolism , Animals , Energy Metabolism/physiology , Harmful Algal Bloom/physiology , Muscle Contraction/physiology , Oxidative Stress/physiology , Proteomics/methodsABSTRACT
PURPOSE: The aim of this short communication is to outline our experience in policies and processes of a nuclear medicine service during the COVID-19 outbreak in Singapore. METHODS: We describe the key considerations of policies and processes that have been implemented in our nuclear medicine service since the first case of COVID-19 was confirmed in Singapore General Hospital on 23 January 2020, up to the present time. RESULTS: Infection control, screening of patients and visitors, segregation of risk groups, segregation of staff and service continuity plans, communication and staff welfare, using electronic platforms for multi-disciplinary meetings and tele-reporting are discussed. CONCLUSION: Since our hospital received the first patient with COVID-19 in Singapore, our centre has managed 16 COVID-19 cases to date. There has not been any healthcare worker in our institution who has contracted COVID-19 through patient contact. We have highlighted for discussion some of the policies and processes to prepare a nuclear medicine service for the COVID-19 threat.
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Coronavirus Infections/epidemiology , Disease Outbreaks , Nuclear Medicine , Pneumonia, Viral/epidemiology , COVID-19 , Communication , Coronavirus Infections/prevention & control , Humans , Pandemics/prevention & control , Pneumonia, Viral/prevention & control , Research Report , Risk , SafetyABSTRACT
BACKGROUND: Geriatric depression is a growing public health issue worldwide. This study aims at identifying the relevant neighbourhood attributes, separate from the individual-level characteristics, that are related to the onset of depressive disorders among the geriatric population. METHODS: This study adopts a structural equation modelling (SEM) approach to understand the effect of the neighbourhood environment on geriatric depression, as identified by data collected from community-dwelling elderly living in Hong Kong and Singapore. Using network buffers as the unit of analysis, different features of the neighbourhood environment are captured and analysed. SEM also examines the strength and direction of the relationships using different parameters at both the individual and neighbourhood levels, as well as the prevalence of depressive symptoms among the elderly. RESULTS: The total sample size is 347, with 173 and 174 elderly people in Hong Kong and Singapore respectively. The results show that in addition to one's physical health status, both objective and subjective neighbourhood factors including the size of parks, land use mix, walkability, and connectivity are all statistically significant influential factors in geriatric depression. In particular, enhancing walkability and providing more parks at the neighbourhood level can bring mental health benefits. CONCLUSIONS: Public health policy initiatives aimed at tackling geriatric depression can be achieved by adopting a holistic and integrative approach to better prepare the neighbourhood environment in an ageing society.
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Depression , Residence Characteristics , Aged , Cross-Sectional Studies , Depression/diagnosis , Depression/epidemiology , Health Status , Hong Kong/epidemiology , Humans , Singapore/epidemiologyABSTRACT
Mineral trioxide aggregate (MTA) pulpotomy may be an alternative to root canal therapy, with reported success rates as high as 85%. However, little technique-specific information has been reported regarding MTA placement in 1 visit. The purpose of this study was to evaluate different placement methods for MTA and resin-modified glass ionomer (RMGI) cement before immediate restoration with amalgam. Forty pulpotomized extracted third molars were randomly divided into 4 groups, and moist cotton was used to simulate pulp tissue in all teeth. In group 1, cotton was placed over the entire pulp chamber floor and in each canal orifice, and MTA was placed over the cotton. The procedure for group 2 was the same as that for group 1 except that a layer of RMGI was placed over the MTA. In group 3, cotton was placed in the canal orifices only, a layer of MTA was placed only over the cotton in the orifices, and RMGI was layered over the MTA and pulp chamber floor. The procedure for group 4 was the same as that for group 3 except that RMGI was placed over the MTA but not on the pulpal floor. Each of these procedures was followed by amalgam condensation. After a 7-day setting period, restored teeth were sectioned mesiodistally, photographed, measured, and evaluated for disturbance of the MTA-restoration junction. The study findings showed that the MTA layer was disturbed in 40% of the specimens in group 1, whereas 10%-20% of specimens in groups 2 through 4 demonstrated disturbed MTA. Analysis with a Pearson chi-square test indicated that the difference between group 1 and groups 2 through 4 was statistically significant (P < 0.05), but there was no significant difference (P > 0.05) between groups 2, 3, and 4. Group 3, in which MTA was placed over each canal orifice and RMGI was placed over the entire pulpal floor, performed best--only 10% of specimens exhibited deformed MTA. The findings suggest that RMGI may protect initially placed MTA during amalgam condensation.
Subject(s)
Aluminum Compounds/administration & dosage , Calcium Compounds/administration & dosage , Dental Restoration, Permanent/methods , Oxides/administration & dosage , Pulpotomy , Root Canal Filling Materials , Silicates/administration & dosage , Drug Combinations , Humans , Pulpotomy/instrumentation , Pulpotomy/methods , Treatment OutcomeABSTRACT
The characteristic sonographic finding of subacute thyroiditis of a heterogeneous poorly defined hypoechoic area in the thyroid gland may mimic that of thyroid malignancy. This finding needs to be interpreted in the correct clinical context to avoid an unnecessary biopsy. We describe 3 patients who underwent thyroid biopsy on the basis of suspicious sonographic findings but who subsequently had a diagnosis of subacute thyroiditis.
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Thyroiditis, Subacute/diagnostic imaging , Ultrasonography/methods , Adult , Aged , Biopsy , Diagnosis, Differential , Female , Humans , Male , Thyroid Gland/diagnostic imaging , Thyroid Gland/pathologyABSTRACT
This article provides a brief overview of the current state of hybrid single-photon emission computed tomography/computer tomography (SPECT/CT) imaging in musculoskeletal infections. SPECT/CT imaging, compared with conventional planar study and SPECT alone, provides improved anatomic localization of infection and more accurate delineation of the extent of infection. This article emphasizes three clinical aspects where SPECT/CT is found to be most useful: differentiating between soft tissue and bone infections, assessing suspected infected sites with underlying structural bone alterations, and defining infective focus when complex anatomy is involved. The accurate assessment of site of infection is vital for selecting the most appropriate therapeutic strategy. Other advantages of SPECT/CT imaging such as reducing the inconvenience of combination planar studies, providing additional CT information, and increasing interobserver agreement are also discussed.
Subject(s)
Infections/diagnosis , Musculoskeletal Diseases/diagnosis , Tomography, Emission-Computed, Single-Photon/methods , Tomography, X-Ray Computed/methods , Bone Diseases/diagnosis , Child , Foot Diseases/diagnosis , Gallium Radioisotopes , Humans , Indium Radioisotopes , Postoperative Complications/diagnosis , Soft Tissue Infections/diagnosis , Spinal Diseases/diagnosis , Technetium Tc 99m Exametazime , Technetium Tc 99m Medronate , Wounds and Injuries/complicationsABSTRACT
INTRODUCTION: Emerging literature suggests that wearable devices offer a promising option for self-directed home-based upper limb training for persons with stroke. However, little research is available to explore integrating smartphone applications with wearable devices to provide upper limb telerehabilitation to stroke survivors at home. This study examined the feasibility and potential therapeutic effects of a wearable device integrated with a smartphone-based telerehabilitation system to provide upper limb rehabilitation to stroke survivors at home. METHODS: Twelve stroke survivors from community support groups participated in a treatment consisting of 4-week telerehabilitation using a wearable device and 4-week conventional therapy successively in a single-blind, randomised crossover study. A 3-week washout period was administered between the two 4-week treatments. The primary outcome measures were the Fugl Meyer Assessment, the Action Research Arm Test, and the active range of motion (ROM) of the upper limb. Secondary outcome measures included the Motor Activity Log and exercise adherence. RESULTS: Results showed that the active ROM of participants' hemiplegic shoulder improved more significantly after 4 weeks of telerehabilitation with the wearable device than with conventional therapy. No significant differences were found in other outcome measures. CONCLUSIONS: A 4-week telerehabilitation programme using a wearable device improves the hemiplegic upper limb in community-dwelling stroke survivors and may be feasible as an effective intervention for self-directed upper limb rehabilitation at home.
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INTRODUCTION: Wearables have emerged as a transformative rehabilitation tool to provide self-directed training in the home. Objective. In this study, we examined the efficacy of a novel wearable device, "Smart Reminder" (SR), to provide home-based telerehabilitation for hemiparetic upper limb (UL) training in persons with stroke. METHODS: Forty stroke survivors from community support groups were randomized (stratified by the period after stroke onset and impairment severity) to either the SR group or the sham device group. Participants received either 20 hours of telerehabilitation using the SR device or training with pictorial handouts and a sham device over 4 weeks. In addition, all participants wore a standard accelerometer for 3 hours each day, 5 times a week, outside the prescribed training. Participants were assessed by a masked assessor at baseline, post-intervention (week 4), and follow-up (week 8). The outcome measures included Fugl-Meyer Assessment for Upper Extremity (FMA-UE), Action Research Arm Test, Motor Activity Log, muscle strength, active range of motion and amount of movement of the UL, and compliance rate of training. RESULTS: The SR group improved substantially in their FMA-UE scores after treatment (mean difference = 2.05, P = .036) compared to the sham group. Also, adherence to the training using the SR device was significantly higher, 97%, than the sham group, 82.3% (P = .038). CONCLUSION: The 4-week telerehabilitation program using a "SR" device demonstrated potential efficacy in improving FMA-UE scores of the hemiparetic upper limb. However, it did not significantly enhance the performance of the affected limb in daily activities. The trial was registered on ClinicalTrial.gov (URL: http://www.clinicaltrials.gov) with the identifier NCT05877183.
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ABSTRACT: A 58-year-old woman with poorly controlled diabetes, peripheral vascular disease, and end-stage renal disease requiring hemodialysis was referred for 18 F-FDG PET/CT to evaluate for source of sepsis. She had history of prior left forefoot and right second toe amputation, as well as left lower-limb dry gangrene for which she declined surgical management. We present a case of a nonamputated lower limb demonstrating regions of absolute photopenia, consistent with dry gangrene.
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Fluorodeoxyglucose F18 , Positron Emission Tomography Computed Tomography , Female , Humans , Middle Aged , Gangrene , Positron-Emission Tomography , FootABSTRACT
Our objective was to demonstrate primarily the safety and secondarily the efficacy of 90Y glass microspheres in selective internal radiation therapy (SIRT) for hepatocellular carcinoma (HCC) in a local Southeast Asian hospital. Methods: Eleven consecutive patients with small, unresectable, nonmetastatic HCC and referred for locoregional therapy with SIRT with a curative intention were followed up for 6 mo after the procedure by way of interviews, blood tests, and anatomic scans. Results: Although 5 patients had deranged liver function tests after the procedure, in only 1 patient did this constitute a grade 1 toxicity (in alkaline phosphatase) by the Common Terminology Criteria for Adverse Events. Half the patients showed a reduction in serum α-fetoprotein measurements, and 6 of 11 patients demonstrated an objective response (complete or partial) on imaging. Conclusion: SIRT with 90Y glass microspheres is a safe and efficacious locoregional therapy for unresectable HCC. There are similar articles published in the West; however, the patient population there comprises far fewer Asians and the underlying cause for HCC is different from that in the Asian population. Despite these differences, SIRT is an equally effective and safe option for such patients.
Subject(s)
Carcinoma, Hepatocellular , Glass , Liver Neoplasms , Microspheres , Yttrium Radioisotopes , Humans , Carcinoma, Hepatocellular/radiotherapy , Liver Neoplasms/radiotherapy , Yttrium Radioisotopes/therapeutic use , Male , Middle Aged , Female , Aged , Treatment Outcome , Safety , Asia, Southeastern , Southeast Asian PeopleABSTRACT
Widespread adoption of mpMRI has led to a decrease in the number of patients requiring prostate biopsies. 68Ga-PSMA-11 PET/CT has demonstrated added benefits in identifying csPCa. Integrating the use of these imaging techniques may hold promise for predicting the presence of csPCa without invasive biopsy. A retrospective analysis of 42 consecutive patients who underwent mpMRI, 68Ga-PSMA-11 PET/CT, prostatic biopsy, and radical prostatectomy (RP) was carried out. A lesion-based model (n = 122) using prostatectomy histopathology as reference standard was used to analyze the accuracy of 68Ga-PSMA-11 PET/CT, mpMRI alone, and both in combination to identify ISUP-grade group ≥ 2 lesions. 68Ga-PSMA-11 PET/CT demonstrated greater specificity and positive predictive value (PPV), with values of 73.3% (vs. 40.0%) and 90.1% (vs. 82.2%), while the mpMRI Prostate Imaging Reporting and Data System (PI-RADS) 4-5 had better sensitivity and negative predictive value (NPV): 90.2% (vs. 78.5%) and 57.1% (vs. 52.4%), respectively. When used in combination, the sensitivity, specificity, PPV, and NPV were 74.2%, 83.3%, 93.2%, and 51.0%, respectively. Subgroup analysis of PI-RADS 3, 4, and 5 lesions was carried out. For PI-RADS 3 lesions, 68Ga-PSMA-11 PET/CT demonstrated a NPV of 77.8%. For PI-RADS 4-5 lesions, 68Ga-PSMA-11 PET/CT achieved PPV values of 82.1% and 100%, respectively, with an NPV of 100% in PI-RADS 5 lesions. A combination of 68Ga-PSMA-11 PET/CT and mpMRI improved the radiological diagnosis of csPCa. This suggests that avoidance of prostate biopsy prior to RP may represent a valid option in a selected subgroup of high-risk patients with a high suspicion of csPCa on mpMRI and 68Ga-PSMA-11 PET/CT.
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BACKGROUND: IgG4-related disease (IgG4-RD) is a heterogeneous autoimmune disorder characterised by inflammatory lesions. Diagnostic imaging, such as 2-[18F]FDG PET/CT, is critical in evaluation of the disease, especially for potentially lethal cardiovascular manifestations. This retrospective study examines the usefulness of semi-quantitative parameters of 2-[18F]FDG PET/CT in monitoring IgG4-RD in patients with and without cardiovascular manifestations. METHODS: Patients diagnosed with IgG4-RD who underwent a 2-[18F]FDG PET/CT scan were identified and classified based on presence or absence of cardiovascular disease. Clinical and laboratory data were extracted and compared to three 2-[18F]FDG PET/CT semi-quantitative parameters: maximum standardised uptake value (SUVmax), metabolic tumour volume (MTV), and total lesion glycolysis (TLG). Tissue-to-background blood (TBR) values were also evaluated for cardiovascular manifestations. These data were also compared in patients before and after receiving immunosuppressive therapy. RESULTS: Forty-six patients identified were divided into an eight member subgroup of patients with cardiovascular manifestations, and a thirty-eight member subgroup of patients without. Patients with cardiovascular lesions were most frequently identified incidentally on imaging evaluation for other diseases (37.5%), with none presenting with chest pain or other cardiovascular symptoms. Ten patients with pre-treatment and post-treatment 2-[18F]FDG PET/CT scans demonstrated significant decreases in all semi-quantitative parameters, with no significant decrease in total IgG or ESR. The decrease in SUVmax, MTV, TLG following therapy was replicated in patients with and without cardiovascular manifestations. CONCLUSION: 2-[18F]FDG PET/CT is an important investigation to determine all sites of involvement in this multisystemic disease and to rule out life-threatening cardiovascular manifestations even in the absence of symptoms. Semi-quantitative parameters such as SUVmax, MTV, TLG, and TBR are useful in assessing treatment response in patients. There are no serological substitutes that can quantify the extent of disease involvement like 2-[18F]FDG PET/CT.
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AIM: Lutetium-177 (Lu-177) prostate-specific membrane antigen radioligand therapy (PSMA-RLT) is a promising therapy for metastatic castration-resistant prostate cancer (mCRPC), but there is limited data of its efficacy and safety in Asian population. We aim to explore the clinical outcomes of Lu-177 PSMA-RLT in this population. METHODS: We evaluated 84 patients with progressive mCRPC receiving Lu-177 PSMA-RLT between 9 May 2018 and 21 February 2022. Lu-177-PSMA-I&T was administered at 6-8-week intervals. Primary end point was overall survival (OS), and secondary end points included prostate-specific antigen (PSA) progression-free survival (PFS), PSA response rate, clinical response, toxicity assessment, and prognostic indicators. RESULTS: The median OS and PSA PFS were 12.2 and 5.2 months, respectively. PSA decline of ≥50% was observed in 51.8% of patients. Patients achieving PSA response had longer median OS (15.0 vs. 9.5 months, p = .03) and PSA PFS (6.5 vs. 2.9 months, p < .001). Pain score improvement was seen in 19 out of 34 patients. A hematotoxicity of ≥grade 3 was observed in 13 out of 78 patients. Multivariable analyses showed that PSA velocity, alkaline phosphatase, hemoglobin (Hb), and the number of treatment cycles were independent prognostic indicators for OS. The retrospective design was the main limitation of the study. CONCLUSIONS: Our study demonstrated a similar safety and efficacy of Lu-177 PSMA-RLT in Asian mCRPC patients compared to the existing literature. A PSA decline ≥50% was associated with longer OS and PSA PFS. Several prognostic indicators for patient outcomes were also identified.