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1.
Article in English | MEDLINE | ID: mdl-38837630

ABSTRACT

OBJECTIVE: TFG mutations have previously been implicated in autosomal recessive hereditary spastic paraplegia (HSP), also known as SPG57. This study aimed to investigate the clinical and molecular features of TFG mutations in a Taiwanese HSP cohort. METHODS: Genetic analysis of TFG was conducted in 242 unrelated Taiwanese HSP patients using a targeted resequencing panel covering the entire coding regions of TFG. Functional assays were performed using an in vitro cell model to assess the impact of TFG variants on protein function. Additionally, other representative TFG mutant proteins were examined to understand the broader implications of TFG mutations in HSP. RESULTS: The study identified a novel homozygous TFG c.177A>C (p.(Lys59Asn)) variant in a family with adolescent-onset, pure form HSP. Functional analysis revealed that the Lys59Asn TFG variant, similar to other HSP-associated TFG mutants, exhibited a low affinity between TFG monomers and abnormal assembly of TFG homo-oligomers. These structural alterations led to aberrant intracellular distribution, compromising TFG's protein secretion function and resulting in decreased cellular viability. INTERPRETATION: These findings confirm that the homozygous TFG c.177A>C (p.(Lys59Asn)) variant is a novel cause of SPG57. The study expands our understanding of the clinical and mutational spectrum of TFG-associated diseases, highlighting the functional defects associated with this specific TFG variant. Overall, this research contributes to the broader comprehension of the genetic and molecular mechanisms underlying HSP.

2.
BMJ Case Rep ; 17(6)2024 Jun 05.
Article in English | MEDLINE | ID: mdl-38839411

ABSTRACT

Cerebriform sebaceous naevus (CSN) is a rare morphological sebaceous naevus variant and challenging to diagnose prenatally due to its flat, smooth and waxy appearance and lack of association with extracutaneous manifestations.A multigravida was referred to our tertiary obstetric unit at 24 weeks of gestation for evaluation of fetal auricular lesions. We were able to further characterise the lesions via serial obstetric ultrasound imaging with the aid of three-dimensional (3D) technology. Although the precise diagnosis prenatally was uncertain, the use of 3D technology allowed the reconstruction of the fetal cutaneous lesions for multidisciplinary assessment to facilitate the development of a neonatal management plan. The diagnosis of CSN was made postnatally on biopsy.


Subject(s)
Ultrasonography, Prenatal , Humans , Female , Pregnancy , Adult , Nevus, Sebaceous of Jadassohn/pathology , Nevus, Sebaceous of Jadassohn/diagnosis , Nevus, Sebaceous of Jadassohn/diagnostic imaging , Infant, Newborn , Nevus/diagnostic imaging , Nevus/pathology , Nevus/diagnosis , Imaging, Three-Dimensional , Skin Neoplasms/pathology , Skin Neoplasms/diagnostic imaging , Skin Neoplasms/diagnosis , Sebaceous Gland Neoplasms/pathology , Sebaceous Gland Neoplasms/diagnosis , Sebaceous Gland Neoplasms/diagnostic imaging
3.
Sci Rep ; 14(1): 12921, 2024 06 05.
Article in English | MEDLINE | ID: mdl-38839809

ABSTRACT

We probed the associations of preoperative modified geriatric nutritional risk index (mGNRI) values with prognosis in patients receiving surgery for oral cavity squamous cell carcinoma (OCSCC). This retrospective study analyzed the clinical data of 333 patients with OCSCC and undergoing surgery between 2008 and 2017. The preoperative mGNRI was calculated using the following formula: (14.89/C-reactive protein level) + 41.7 × (actual body weight/ideal body weight). We executed receiver operating characteristic curve analyses to derive the optimal mGNRI cutoff and employed Kaplan-Meier survival curves and Cox proportional hazard model to probe the associations of the mGNRI with overall survival (OS) and disease-free survival (DFS). The optimal mGNRI cutoff was derived to be 73.3. We noted the 5-year OS and DFS rates to be significantly higher in the high-mGNRI group than in the low-mGNRI group (both p < 0.001). A preoperative mGNRI below 73.3 was independently associated with unfavorable DFS and OS. A mGNRI-based nomogram was constructed to provide accurate OS predictions (concordance index, 0.781). Hence, preoperative mGNRI is a valuable and cost-effective prognostic biomarker in patients with OCSCC. Our nomogram facilitates the practical use of mGNRI and offers individualized predictions of OS.


Subject(s)
Mouth Neoplasms , Nutrition Assessment , Humans , Female , Male , Mouth Neoplasms/surgery , Mouth Neoplasms/mortality , Mouth Neoplasms/pathology , Aged , Prognosis , Retrospective Studies , Middle Aged , Geriatric Assessment/methods , Carcinoma, Squamous Cell/surgery , Carcinoma, Squamous Cell/pathology , Nutritional Status , Aged, 80 and over , Kaplan-Meier Estimate , Disease-Free Survival , ROC Curve , Risk Factors , Proportional Hazards Models , Risk Assessment/methods
4.
Front Cell Dev Biol ; 12: 1347126, 2024.
Article in English | MEDLINE | ID: mdl-38827524

ABSTRACT

Osteoarthritis (OA) is a chronic disease affecting joints and further causing disabilities. This disease affects around 240 million people worldwide. It is a multifactorial disease, and its etiology is difficult to determine. Although numerous therapeutic strategies are available, the therapies are aimed at reducing pain and improving patients' quality of life. Hence, there is an urgent need to develop disease-modifying drugs (DMOAD) that can reverse or halt OA progression. Apoptosis is a cell removal process that is important in maintaining homeostatic mechanisms in the development and sustaining cell population. The apoptosis of chondrocytes is believed to play an important role in OA progression due to poor chondrocytes self-repair abilities to maintain the extracellular matrix (ECM). Hence, targeting chondrocyte apoptosis can be one of the potential therapeutic strategies in OA management. There are various mediators and targets available to inhibit apoptosis such as autophagy, endoplasmic reticulum (ER) stress, oxidative stress, and inflammation. As such, this review highlights the importance and potential targets that can be aimed to reduce chondrocyte apoptosis.

5.
Article in English | MEDLINE | ID: mdl-38829967

ABSTRACT

OBJECTIVES: Access to hepatocellular carcinoma (HCC) surveillance and treatments were disrupted during the COVID-19 pandemic. We aimed to characterize the impact of the pandemic on HCC incidence and mortality rates, treatment and outcomes in the U.S. METHODS: Two nationwide databases, the United States Cancer Statistics and the National Vital Statistics System, were used to investigate HCC incidence and mortality between 2001-2020. Trends in age-adjusted incidence (aIR) and mortality (aMR) rates were assessed using joinpoint analysis. The 2020 aIR and aMR were projected based on the pre-pandemic data and compared to actual values to assess the extent of underdiagnosis. We assessed differences in HCC characteristics, treatment and overall survival (OS) between 2020 and 2018-2019. RESULTS: The aIR of HCC in 2020 was significantly reduced compared to 2019 (5.22 vs 6.03/100K PY), representing a 12.2% decrease compared to the predicted aIR in 2020 (5.94/100K PY). The greatest extent of underdiagnosis was observed in Black (-14.87%) and Hispanic (-14.51%) individuals and those with localized HCC (-15.12%). Individuals staged as regional or distant HCC were also less likely to receive treatment in 2020. However, there was no significant difference in short-term OS in 2020 compared to 2018-2019, with HCC mortality rates remaining stable (aMR: 2.76 vs 2.73/100K PY in 2020 vs 2019). CONCLUSIONS: The COVID-19 pandemic resulted in underdiagnosis of HCC, particularly early-stage disease and racial ethnic minorities, and underuse of HCC-directed treatment. Longer follow-up is needed to determine the impact of the COVID-19 pandemic on HCC-related mortality.

6.
J Craniofac Surg ; 2024 Jun 07.
Article in English | MEDLINE | ID: mdl-38847498

ABSTRACT

OBJECTIVE: Flexible nasopharyngoscopy is a common procedure for evaluating the hypopharynx. The modified Killian method has been reported to enhance visualization during this examination. The aim of this study was to compare the visibility of the hypopharynx using conventional and modified Killian methods. METHODS: A systematic literature search was conducted in PubMed, EMBASE, and the Cochrane Library to identify studies that compared the visibility of the hypopharynx using the 2 methods. Comprehensive meta-analysis software was used to analyze the data. Studies that evaluated the overall hypopharyngeal visibility score and the visibility of the pyriform sinus, postcricoid region, and upper esophageal sphincter were included. RESULTS: Five studies were included in the analysis. The pooled results showed that the modified Killian method significantly improved overall visibility score (SMD=1.09; 95% CI, 0.39-1.80) and complete visibility of the pyriform sinus, postcricoid region, and upper esophageal sphincter (log OR=3.83; 95% CI, 2.30-5.35; log OR=4.20; 95% CI, 3.21-5.19; log OR=3.38; 95% CI, 1.68-5.08). CONCLUSION: The modified Killian method is a valuable technique for improving hypopharyngeal visibility during flexible nasopharyngoscopy. This technique can enhance the detection of potential abnormalities or lesions, leading to better diagnostic accuracy and improved patient outcomes.

9.
Int J Rheum Dis ; 27(5): e15162, 2024 May.
Article in English | MEDLINE | ID: mdl-38720421

ABSTRACT

BACKGROUND: Recent findings suggest a link between gout and the development of dementia. Early treatment with colchicine is recommended as a first-line therapy for gout flares. Animal studies demonstrate that colchicine could induce cognitive impairment. This cohort study aimed to investigate the association between colchicine use and the risk of developing dementia. METHODS: In this nationwide cohort study, we performed comparative analysis on 6147 patients ≥40 years, with gout and colchicine new users against 6147 controls to assess subsequent dementia risk. The colchicine group and the control group (urate lowering therapy group) were matched on the bases of age, sex, index year, and comorbidities. All participants were followed for up to 14 years for a diagnosis of dementia considering medical records were retrospectively checked over this period. Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). Sensitivity analyses were performed to validate our findings. RESULTS: The adjusted hazard ratio (aHR) of dementia for colchicine users was 1.45 (95% CI = 1.05, 1.99) relative to comparison group after adjusting for sex, age, and comorbidities. Sensitivity analysis aiming to minimize underdiagnosed occult dementia at the time of index year yielded consistent positive association. In higher accumulative dose colchicine group (cumulative defined daily dose [cDDD] >30), the aHR of dementia risk for colchicine users was 1.42 (95% CI = 1.03, 1.97) compared with nonusers. For those duration of colchicine use >30 days, the aHR was 1.53 (95% CI = 1.01-2.32) compared to the nonuser group. CONCLUSIONS: A significant risk of dementia was observed in this study in patients with gout using colchicine at higher cDDD and for a longer period. Further research is needed to elucidate the relationship between colchicine, gout, and dementia.


Subject(s)
Colchicine , Dementia , Gout Suppressants , Gout , Humans , Colchicine/adverse effects , Colchicine/therapeutic use , Gout/epidemiology , Gout/drug therapy , Dementia/epidemiology , Dementia/chemically induced , Dementia/diagnosis , Female , Male , Retrospective Studies , Aged , Middle Aged , Gout Suppressants/adverse effects , Risk Factors , Risk Assessment , Time Factors , Taiwan/epidemiology , Adult , Aged, 80 and over , Databases, Factual
11.
Medicine (Baltimore) ; 103(20): e38114, 2024 May 17.
Article in English | MEDLINE | ID: mdl-38758906

ABSTRACT

Early identification of the sources of infection in emergency department (ED) patients of sepsis remains challenging. Computed tomography (CT) has the potential to identify sources of infection. This retrospective study aimed to investigate the role of CT in identifying sources of infection in patients with sepsis without obvious infection foci in the ED. A retrospective chart review was conducted on patients with fever and sepsis visiting the ED of Linkou Chang Gung Memorial Hospital between July 1, 2020 and June 30, 2021. Data on patient demographics, vital signs, clinical symptoms, underlying medical conditions, laboratory results, administered interventions, length of hospital stay, and mortality outcomes were collected and analyzed. Of 218 patients included in the study, 139 (63.8%) had positive CT findings. The most common sources of infection detected by CT included liver abscesses, acute pyelonephritis, and cholangitis. Laboratory results showed that patients with positive CT findings had higher white blood cell and absolute neutrophil counts and lower hemoglobin levels. Positive blood culture results were more common in patients with positive CT findings. Additionally, the length of hospital stay was longer in the group with positive CT findings. Multivariate logistic regression analysis revealed that hemoglobin levels and positive blood culture results independently predicted positive CT findings in patients with fever or sepsis without an obvious source of infection. In patients with sepsis with an undetermined infection focus, those presenting with leukocytosis, anemia, and elevated absolute neutrophil counts tended to have positive findings on abdominal CT scans. These patients had high rates of bacteremia and longer lengths of stay. Abdominal CT remains a valuable diagnostic tool for identifying infection sources in carefully selected patients with sepsis of undetermined infection origins.


Subject(s)
Sepsis , Tomography, X-Ray Computed , Humans , Male , Retrospective Studies , Female , Tomography, X-Ray Computed/methods , Sepsis/diagnostic imaging , Middle Aged , Aged , Length of Stay/statistics & numerical data , Emergency Service, Hospital , Liver Abscess/diagnostic imaging , Adult , Pyelonephritis/diagnostic imaging , Cholangitis/diagnostic imaging , Aged, 80 and over , Fever of Unknown Origin/diagnostic imaging
12.
Pathogens ; 13(5)2024 May 15.
Article in English | MEDLINE | ID: mdl-38787263

ABSTRACT

Actinobacillus pleuropneumoniae (APP) is a major cause of lung infections in pigs. An experimental mouse has the edge over pigs pertaining to the ease of experimental operation, disease study and therapy, abundance of genetic resources, and cost. However, it is a challenge to introduce APP into a mouse lung due to the small respiratory tract of mice and bacterial host tropism. In this study, an effective airborne transmission of APP serovar 1 (APP1) was developed in mice for lung infection. Consequently, APP1 infected BALB/c mice and caused 60% death within three days of infection at the indicated condition. APP1 seemed to enter the lung and, in turn, spread to other organs of the mice over the first 5 days after infection. Accordingly, APP1 damaged the lung as evidenced by its morphological and histological examinations. Furthermore, ampicillin fully protected mice against APP1 as shown by their survival, clinical symptoms, body weight loss, APP1 count, and lung damages. Finally, the virulence of two extra APP strains, APP2 and APP5, in the model was compared based on the survival rate of mice. Collectively, this study successfully established a fast and reliable mouse model of APP which can benefit APP research and therapy. Such a model is a potentially useful model for airway bacterial infections.

13.
J Cell Biol ; 223(7)2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38748249

ABSTRACT

Bacteria, omnipresent in our environment and coexisting within our body, exert dual beneficial and pathogenic influences. These microorganisms engage in intricate interactions with the human body, impacting both human health and disease. Simultaneously, certain organelles within our cells share an evolutionary relationship with bacteria, particularly mitochondria, best known for their energy production role and their dynamic interaction with each other and other organelles. In recent years, communication between bacteria and mitochondria has emerged as a new mechanism for regulating the host's physiology and pathology. In this review, we delve into the dynamic communications between bacteria and host mitochondria, shedding light on their collaborative regulation of host immune response, metabolism, aging, and longevity. Additionally, we discuss bacterial interactions with other organelles, including chloroplasts, lysosomes, and the endoplasmic reticulum (ER).


Subject(s)
Bacteria , Host-Pathogen Interactions , Mitochondria , Animals , Humans , Bacteria/metabolism , Endoplasmic Reticulum/metabolism , Endoplasmic Reticulum/microbiology , Lysosomes/metabolism , Lysosomes/microbiology , Mitochondria/metabolism , Organelles/metabolism
14.
Nat Aging ; 2024 May 30.
Article in English | MEDLINE | ID: mdl-38816550

ABSTRACT

Organismal aging involves functional declines in both somatic and reproductive tissues. Multiple strategies have been discovered to extend lifespan across species. However, how age-related molecular changes differ among various tissues and how those lifespan-extending strategies slow tissue aging in distinct manners remain unclear. Here we generated the transcriptomic Cell Atlas of Worm Aging (CAWA, http://mengwanglab.org/atlas ) of wild-type and long-lived strains. We discovered cell-specific, age-related molecular and functional signatures across all somatic and germ cell types. We developed transcriptomic aging clocks for different tissues and quantitatively determined how three different pro-longevity strategies slow tissue aging distinctively. Furthermore, through genome-wide profiling of alternative polyadenylation (APA) events in different tissues, we discovered cell-type-specific APA changes during aging and revealed how these changes are differentially affected by the pro-longevity strategies. Together, this study offers fundamental molecular insights into both somatic and reproductive aging and provides a valuable resource for in-depth understanding of the diversity of pro-longevity mechanisms.

15.
Oecologia ; 2024 May 28.
Article in English | MEDLINE | ID: mdl-38806949

ABSTRACT

Community weighted means (CWMs) are widely used to study the relationship between community-level functional traits and environment. For certain null hypotheses, CWM-environment relationships assessed by linear regression or ANOVA and tested by standard parametric tests are prone to inflated Type I error rates. Previous research has found that this problem can be solved by permutation tests (i.e., the max test). A recent extension of the CWM approach allows the inclusion of intraspecific trait variation (ITV) by the separate calculation of fixed, site-specific, and intraspecific CWMs. The question is whether the same Type I error rate inflation exists for the relationship between environment and site-specific or intraspecific CWM. Using simulated and real-world community datasets, we show that site-specific CWM-environment relationships have also inflated Type I error rate, and this rate is negatively related to the relative ITV magnitude. In contrast, for intraspecific CWM-environment relationships, standard parametric tests have the correct Type I error rate, although somewhat reduced statistical power. We introduce an ITV-extended version of the max test, which can solve the inflation problem for site-specific CWM-environment relationships and, without considering ITV, becomes equivalent to the "original" max test used for the CWM approach. We show that this new ITV-extended max test works well across the full possible magnitude of ITV on both simulated and real-world data. Most real datasets probably do not have intraspecific trait variation large enough to alleviate the problem of inflated Type I error rate, and published studies possibly report overly optimistic significance results.

16.
Article in English | MEDLINE | ID: mdl-38805142

ABSTRACT

Marine antimicrobial peptides have been demonstrated in numerous studies to possess anti-cancer properties. This research investigation aimed to explore the fundamental molecular mechanisms underlying the antitumor activity of Tilapia piscidin 4 (TP4), an antimicrobial peptide, in human bladder cancer. TP4 exhibited a remarkable inhibitory effect on the proliferation of bladder cancer cells through cell cycle arrest at the G2/M phase. Additionally, TP4 upregulated the expression of cleaved caspase-3, caspase-9, and PARP, leading to the activation of apoptotic pathways in bladder cancer cells. TP4 exhibit a marked rise in mitochondria reactive oxygen species, leading to the subsequent loss of potential for the mitochondrial membrane. Furthermore, the inhibition of mitochondrial oxidative phosphorylation resulted in a decrease in downstream ATP production. Meanwhile, TP4-treated bladder cancer cells showed an increase in Bax and ERK but a decrease in SIRT1, PGC-1α, and Bcl2. ERK activation, SIRT1/PGC-1α-axis, and TP4-induced apoptosis were all significantly reversed by the ERK inhibitor SCH772984. Finally, the inhibitory effect of TP4 on tumor growth has been confirmed in a zebrafish bladder cancer xenotransplantation model. These findings suggest that TP4 may be a potential agents for human bladder cancer through apoptosis induction, ERK activation, and the promotion of SIRT1-mediated signaling pathways.

17.
Sci Rep ; 14(1): 11584, 2024 05 21.
Article in English | MEDLINE | ID: mdl-38773245

ABSTRACT

Climate change and disease threaten shrimp farming. Here, we studied the beneficial properties of a phytogenic formulation, Shrimp Best (SB), in whiteleg shrimp. Functional studies showed that SB dose-dependently increased shrimp body weight and decreased feed conversion ratio. We found that SB protected against Vibrio parahaemolyticus as evidenced by survival rate, bacterial load, and hepatopancreatic pathology in shrimp. Finally, we explored the likely mechanism by which SB affects growth performance and vibriosis in shrimp. The 16S rRNA sequencing data showed that SB increased 6 probiotic genera and decreased 6 genera of pathogenic bacteria in shrimp. Among these, SB increased the proportion of Lactobacillus johnsonii and decreased that of V. parahaemolyticus in shrimp guts. To dissect the relationship among SB, Lactobacillus and Vibrio, we investigated the in vitro regulation of Lactobacillus and Vibrio by SB. SB at ≥ 0.25 µg/mL promoted L. johnsonii growth. Additionally, L. johnsonii and its supernatant could inhibit V. parahaemolyticus. Furthermore, SB could up-regulate five anti-Vibrio metabolites of L. johnsonii, which caused bacterial membrane destruction. In parallel, we identified 3 fatty acids as active compounds from SB. Overall, this work demonstrated that SB improved growth performance and vibriosis protection in shrimp via the regulation of gut microbiota.


Subject(s)
Penaeidae , Vibrio parahaemolyticus , Animals , Penaeidae/microbiology , Penaeidae/growth & development , Vibrio parahaemolyticus/drug effects , Vibrio parahaemolyticus/growth & development , Vibrio parahaemolyticus/pathogenicity , Vibrio Infections/prevention & control , Vibrio Infections/veterinary , Vibrio Infections/microbiology , Lactobacillus/growth & development , RNA, Ribosomal, 16S/genetics , Vibrio/drug effects , Vibrio/pathogenicity , Probiotics
18.
Int J Nurs Pract ; : e13265, 2024 May 21.
Article in English | MEDLINE | ID: mdl-38769905

ABSTRACT

AIM: To assess heart rate variability (HRV) as a measure to assess job stress and sleep quality among nurses in the post-COVID-19 period. BACKGROUND: The COVID-19 pandemic significantly affected nurses, with heightened job stress and impaired sleep quality impacting their well-being and effectiveness in patient care. HRV could offer insights for supporting strategies in the pandemic aftermath. DESIGN: A quantitative cross-sectional study. METHODS: This study involved 403 clinical nurses recruited from a teaching hospital in Taiwan. Data on job stress, work frustration, sleep quality and HRV were collected and analysed. RESULTS: Among the nurses surveyed during the COVID-19 pandemic, 72.7% reported poor sleep quality (PSQI = 9.369). Job stress emerged as a strong predictor of work frustration. High stress levels and poor sleep quality were correlated with significantly decreased HRV, indicating a potential physiological impact of stress on the nurses' health and well-being. CONCLUSIONS: HRV is a valuable and cost-effective measure for monitoring and managing nurses' well-being in the post-COVID-19 era. Targeted interventions can be implemented to support nurses' overall performance and promote their well-being by identifying those at high risk of job stress and poor sleep quality.

19.
Hepatol Commun ; 8(6)2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38780301

ABSTRACT

BACKGROUND: Vertical sleeve gastrectomy (SGx) is a type of bariatric surgery to treat morbid obesity and metabolic dysfunction-associated steatotic liver disease (MASLD). The molecular mechanisms of SGx to improve MASLD are unclear, but increased bile acids (BAs) and FGF19 (mouse FGF15) were observed. FGF15/19 is expressed in the ileum in response to BAs and is critical in not only suppressing BA synthesis in the liver but also promoting energy expenditure. We hypothesized the reduction of obesity and resolution of MASLD by SGx may be mediated by FGF15/19. METHODS: First, we conducted hepatic gene expression analysis in obese patients undergoing SGx, with the results showing increased expression of FGF19 in obese patients' livers. Next, we used wild-type and intestine-specific Fgf15 knockout mice (Fgf15ile-/-) to determine the effects of FGF15 deficiency on improving the metabolic effects. RESULTS: SGx improved metabolic endpoints in both genotypes, evidenced by decreased obesity, improved glucose tolerance, and reduced MASLD progression. However, Fgf15ile-/- mice showed better improvement compared to wild-type mice after SGx, suggesting that other mediators than FGF15 are also responsible for the beneficial effects of FGF15 deficiency. Further gene expression analysis in brown adipose tissue suggests increased thermogenesis. CONCLUSIONS: FGF15 deficiency, the larger BA pool and higher levels of secondary BAs may increase energy expenditure in extrahepatic tissues, which may be responsible for improved metabolic functions following SGx.


Subject(s)
Fatty Liver , Fibroblast Growth Factors , Gastrectomy , Mice, Knockout , Obesity, Morbid , Fibroblast Growth Factors/genetics , Fibroblast Growth Factors/metabolism , Animals , Gastrectomy/methods , Mice , Obesity, Morbid/surgery , Obesity, Morbid/genetics , Obesity, Morbid/metabolism , Humans , Male , Fatty Liver/genetics , Fatty Liver/metabolism , Female , Bile Acids and Salts/metabolism , Liver/metabolism , Adult , Middle Aged , Bariatric Surgery , Mice, Inbred C57BL
20.
EJNMMI Phys ; 11(1): 38, 2024 Apr 22.
Article in English | MEDLINE | ID: mdl-38647987

ABSTRACT

BACKGROUND: In order to ensure adequate radiation protection of critical groups such as staff, caregivers and the general public coming into proximity of nuclear medicine (NM) patients, it is necessary to consider the impact of the radiation emitted by the patients during their stay at the hospital or after leaving the hospital. Current risk assessments are based on ambient dose rate measurements in a single position at a specified distance from the patient and carried out at several time points after administration of the radiopharmaceutical to estimate the whole-body retention. The limitations of such an approach are addressed in this study by developing and validating a more advanced computational dosimetry approach using Monte Carlo (MC) simulations in combination with flexible and realistic computational phantoms and time activity distribution curves from reference biokinetic models. RESULTS: Measurements of the ambient dose rate equivalent H*(10) at 1 m from the NM patient have been successfully compared against MC simulations with 5 different codes using the ICRP adult reference computational voxel phantoms, for typical clinical procedures with 99mTc-HDP/MDP, 18FDG and Na131I. All measurement data fall in the 95% confidence intervals, determined for the average simulated results. Moreover, the different MC codes (MCNP-X, PHITS, GATE, GEANT4, TRIPOLI-4®) have been compared for a more realistic scenario where the effective dose rate E of an exposed individual was determined in positions facing and aside the patient model at 30 cm, 50 cm and 100 cm. The variation between codes was lower than 8% for all the radiopharmaceuticals at 1 m, and varied from 5 to 16% for the face-to face and side-by-side configuration at 30 cm and 50 cm. A sensitivity study on the influence of patient model morphology demonstrated that the relative standard deviation of H*(10) at 1 m for the range of included patient models remained under 16% for time points up to 120 min post administration. CONCLUSIONS: The validated computational approach will be further used for the evaluation of effective dose rates per unit administered activity for a variety of close-contact configurations and a range of radiopharmaceuticals as part of risk assessment studies. Together with the choice of appropriate dose constraints this would facilitate the setting of release criteria and patient restrictions.

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