MRI-Based Clinical-Imaging-Radiomics Nomogram Model for Discriminating Between Benign and Malignant Solid Pulmonary Nodules or Masses.

RATIONALE AND OBJECTIVES: Pulmonary nodules or masses are highly prevalent worldwide, and differential diagnosis of benign and malignant lesions remains difficult. Magnetic resonance imaging (MRI) can provide functional and metabolic information of pulmonary lesions. This study aimed to establish a nomogram model based on clinical features, imaging features, and multi-sequence MRI radiomics to identify benign and malignant solid pulmonary nodules or masses. MATERIALS AND METHODS: A total of 145 eligible patients (76 male; mean age, 58.4 years ± 13.7 [SD]) with solid pulmonary nodules or masses were retrospectively analyzed. The patients were randomized into two groups (training cohort, n = 102; validation cohort, n = 43). The nomogram was used for predicting malignant pulmonary lesions. The diagnostic performance of different models was evaluated by receiver operating characteristic (ROC) curve analysis. RESULTS: Of these patients, 95 patients were diagnosed with benign lesions and 50 with malignant lesions. Multivariate analysis showed that age, DWI value, LSR value, and ADC value were independent predictors of malignant lesions. Among the radiomics models, the multi-sequence MRI-based model (T1WI+T2WI+ADC) achieved the best diagnosis performance with AUCs of 0.858 (95%CI: 0.775, 0.919) and 0.774 (95%CI: 0.621, 0.887) for the training and validation cohorts, respectively. Combining multi-sequence radiomics, clinical and imaging features, the predictive efficacy of the clinical-imaging-radiomics model was significantly better than the clinical model, imaging model and radiomics model (all P < 0.05). CONCLUSION: The MRI-based clinical-imaging-radiomics model is helpful to differentiate benign and malignant solid pulmonary nodules or masses, and may be useful for precision medicine of pulmonary diseases.

Application of the mild behavioral impairment checklist in Chinese patients with the behavioral variant of frontotemporal dementia.

BACKGROUND: The mild behavioral impairment checklist (MBI-C) designed to capture neuropsychiatric symptoms in the whole spectrum of elder with or without dementia, have been verified in mild behavioral impairment, mild cognitive impairment and Alzheimer's Disease, but never used in the behavioral variant of frontotemporal dementia (bvFTD). METHODS: Fifty-two patients with bvFTD (mild, n = 30; moderate-severe, n = 22) and 82 community-dwelling elderly individuals (HCs) were enrolled. All subjects were assessed with a full neuropsychological scale including the MBI-C, Neuropsychiatric Inventory Questionnaire (NPI-Q), and Frontal Behavioral Inventory (FBI). Receiver operating characteristic curves were drawn to analyze the sensitivity and specificity of the MBI-C, NPI-Q, and FBI, and cutoff points were determined using the Youden index. RESULTS: The MBI-C and domain scores in all patients with bvFTD were significantly higher than those in HCs. The most common symptoms of bvFTD were apathy (82.7%) and impulse dyscontrol (80.8%). The MBI-C score was positively correlated with the NPI-Q, FBI, and Activities of Daily Living. For differentiating patients with both bvFTD and mild bvFTD from HCs, the optimal MBI-C cutoff point was 5.5 with a sensitivity of 100% and specificity of 82%, and its sensitivity was higher than that of the NPI-Q and FBI. CONCLUSION: The MBI-C is a sensitive tool for screening behavioral and psychological symptoms in patients with bvFTD, even in the early stages of the disease.

Alternative approaches for creating a wealth index: the case of Mozambique.

INTRODUCTION: The wealth index is widely used as a proxy for a household's socioeconomic position (SEP) and living standard. This work constructs a wealth index for the Mopeia district in Mozambique using data collected in year 2021 under the BOHEMIA (Broad One Health Endectocide-based Malaria Intervention in Africa) project. METHODS: We evaluate the performance of three alternative approaches against the Demographic and Health Survey (DHS) method based wealth index: feature selection principal components analysis (PCA), sparse PCA and robust PCA. The internal coherence between four wealth indices is investigated through statistical testing. Validation and an evaluation of the stability of the wealth index are performed with additional household income data from the BOHEMIA Health Economics Survey and the 2018 Malaria Indicator Survey data in Mozambique. RESULTS: The Spearman's rank correlation between wealth index ventiles from four methods is over 0.98, indicating a high consistency in results across methods. Wealth rankings and households' income show a strong concordance with the area under the curve value of ~0.7 in the receiver operating characteristic analysis. The agreement between the alternative wealth indices and the DHS wealth index demonstrates the stability in rankings from the alternative methods. CONCLUSIONS: This study creates a wealth index for Mopeia, Mozambique, and shows that DHS method based wealth index is an appropriate proxy for the SEP in low-income regions. However, this research recommends feature selection PCA over the DHS method since it uses fewer asset indicators and constructs a high-quality wealth index.

BOHEMIA a cluster randomized trial to assess the impact of an endectocide-based one health approach to malaria in Mozambique: baseline demographics and key malaria indicators.

BACKGROUND: Many geographical areas of sub-Saharan Africa, especially in rural settings, lack complete and up-to-date demographic data, posing a challenge for implementation and evaluation of public health interventions and carrying out large-scale health research. A demographic survey was completed in Mopeia district, located in the Zambezia province in Mozambique, to inform the Broad One Health Endectocide-based Malaria Intervention in Africa (BOHEMIA) cluster randomized clinical trial, which tested ivermectin mass drug administration to humans and/or livestock as a potential novel strategy to decrease malaria transmission. METHODS: The demographic survey was a prospective descriptive study, which collected data of all the households in the district that accepted to participate. Households were mapped through geolocation and identified with a unique identification number. Basic demographic data of the household members was collected and each person received a permanent identification number for the study. RESULTS: 25,550 households were mapped and underwent the demographic survey, and 131,818 individuals were registered in the district. The average household size was 5 members and 76.9% of households identified a male household head. Housing conditions are often substandard with low access to improved water systems and electricity. The reported coverage of malaria interventions was 71.1% for indoor residual spraying and 54.1% for universal coverage of long-lasting insecticidal nets. The median age of the population was 15 years old. There were 910 deaths in the previous 12 months reported, and 43.9% were of children less than 5 years of age. CONCLUSIONS: The study showed that the district had good coverage of vector control tools against malaria but sub-optimal living conditions and poor access to basic services. The majority of households are led by males and Mopeia Sede/Cuacua is the most populated locality in the district. The population of Mopeia is young (< 15 years) and there is a high childhood mortality. The results of this survey were crucial as they provided the household and population profiles and allowed the design and implementation of the cluster randomized clinical trial. Trial registration NCT04966702.

Toward an early clinical diagnosis of MM2-type sporadic Creutzfeldt-Jakob disease.

OBJECTIVE: To assess the proportion of clinically diagnosed MM2-type sporadic Creutzfeldt-Jakob disease (sCJD) in a Chinese cohort, describe the clinical features of MM2-cortical (MM2C) and MM2-thalamic (MM2T) type sCJD to improve the early detection of MM2-type sCJD. METHODS: A total of 209 patients with sCJD admitted to the Xuanwu Hospital between February 2012 and August 2022 were reviewed. The patients were classified into probable MM2C, MM2T-type sCJD, and other types of sCJD according to current clinical diagnostic criteria. Clinical and ancillary data were compared between the groups. RESULTS: Fifty-one (24.4%) patients were clinically diagnosed with MM2-type sCJD, of which 44 were diagnosed with MM2C-type sCJD and 7 with MM2T-type sCJD. In the absence of RT-QuIC, 27 (61.3%) patients of MM2C-type sCJD did not meet the US CDC sCJD criteria for possible sCJD on admission, even though the mean period from onset to admission was 6.0 months. However, all of these patients had cortical hyperintensity on DWI. Compared to the other types of sCJD, MM2C-type sCJD was associated with slower disease progression and the absence of the typical clinical features of sCJD; the MM2T-type sCJD group had a higher proportion of males, earlier age of onset, longer duration of disease, and a higher incidence of bilateral thalamic hypometabolism/hypoperfusion. INTERPRETATION: In the absence of multiple typical sCJD symptoms within 6 months, the presence of cortical hyperintensity on DWI should raise concerns for MM2C-type sCJD after excluding other etiologies. Bilateral thalamic hypometabolism/hypoperfusion may be more helpful in the clinical diagnosis of MM2T-type sCJD.

BOHEMIA a cluster randomized trial to assess the impact of an endectocide-based one health approach to malaria in Mozambique: baseline demographics and key malaria indicators

Many geographical areas of sub-Saharan Africa, especially in rural settings, lack complete and up-to-date demographic data, posing a challenge for implementation and evaluation of public health interventions and carrying out large-scale health research. A demographic survey was completed in Mopeia district, located in the Zambezia province in Mozambique, to inform the Broad One Health Endectocide-based Malaria Intervention in Africa (BOHEMIA) cluster randomized clinical trial, which tested ivermectin mass drug administration to humans and/or livestock as a potential novel strategy to decrease malaria transmission. Methods: The demographic survey was a prospective descriptive study, which collected data of all the households in the district that accepted to participate. Households were mapped through geolocation and identified with a unique identification number. Basic demographic data of the household members was collected and each person received a permanent identification number for the study. Results: 25,550 households were mapped and underwent the demographic survey, and 131,818 individuals were registered in the district. The average household size was 5 members and 76.9% of households identified a male household head. Housing conditions are often substandard with low access to improved water systems and electricity. The reported coverage of malaria interventions was 71.1% for indoor residual spraying and 54.1% for universal coverage of long-lasting insecticidal nets. The median age of the population was 15 years old. There were 910 deaths in the previous 12 months reported, and 43.9% were of children less than 5 years of age. Conclusions: The study showed that the district had good coverage of vector control tools against malaria but sub-optimal living conditions and poor access to basic services. The majority of households are led by males and Mopeia Sede/Cuacua is the most populated locality in the district. The population of Mopeia is young (< 15 years) and there is a high childhood mortality. The results of this survey were crucial as they provided the household and population profiles and allowed the design and implementation of the cluster randomized clinical trial. Trial registration NCT04966702.

IMPA2 blocks cervical cancer cell apoptosis and induces paclitaxel resistance through p53-mediated AIFM2 regulation.

Cervical cancer continues to be a concern, and the prognosis of locally advanced cervical cancer remains poor. IMPA2 was previously identified as a potential oncogene and regulator of tumor apoptosis. In this study, we aim to further elucidate the underlying mechanisms of IMPA2 gene in the regulation of cervical cancer apoptosis. First, we identify AIFM2 as an upregulated gene in IMPA2-silenced cervical cancer cells, and inhibition of AIFM2 reverses IMPA2 knockdown-induced apoptosis. Further study reveals that AIFM2 regulates cell apoptosis in a mitochondrial-dependent manner with a redistribution of mitochondrial membrane potential and intracellular Ca 2+ levels. However, the analysis of the STRING database and our experimental results show that AIFM2 has little effect on cervical cancer progression and survival. Further mechanistic study demonstrates that IMPA2 and AIFM2 silencing inhibits apoptosis by activating p53. Meanwhile, the knockdown of IMPA2 enhances the chemosensitivity of cervical cancer cells by strengthening paclitaxel-induced apoptosis. Based on the above results, the IMPA2/AIFM2/p53 pathway may be a new molecular mechanism for paclitaxel treatment of cervical cancer and an effective strategy to enhance the sensitivity of cervical cancer cells to paclitaxel. Our findings display a novel function of IMPA2 in regulating cell apoptosis and paclitaxel resistance mediated by a disturbance of AIFM2 and p53 expression, potentially making it a novel therapeutic target for cervical cancer treatment.

Involvement of specific striatal subregion contributes to executive deficits in Alzheimer disease.

BACKGROUND: There is growing evidence that the striatum plays a central role in cognitive dysfunction. However, it remains unclear whether and how the striatum contributes specifically to executive deficits in Alzheimer disease (AD). We sought to elucidate aberrations in the striatal subregion associated with executive function and its metabolic connectivity with the cortical regions to investigate its role in the pathogenesis of executive deficits in patients with AD. METHODS: Patients with AD and healthy controls underwent a neuropsychological assessment battery, including assessment of executive function, and a hybrid positron emission tomography/magnetic resonance imaging (PET/MRI) scan. We performed voxel-wise analyses of cerebral metabolism between patients and controls, focusing on the executive subregion of the striatum according to the Oxford-GSK-Imanova Striatal Connectivity Atlas. We assessed the correlation between the [18F]-fluorodeoxyglucose standardized uptake value ratio of the striatal executive subregion and clinical variables, and we analyzed seed-based metabolic connectivity of the striatal executive subregion with the dorsolateral prefrontal cortex (DLPFC) using [18F]-fluorodeoxyglucose PET. RESULTS: We included 50 patients with AD and 33 controls in our analyses. The patterns of striatal hypometabolism in patients with AD were specific to executive and caudal motor subregions. Metabolic activity in the executive subregion of the striatum correlated negatively with the severity of executive dysfunction, as measured with the Trial-Making Test (TMT) part B and the difference score TMT B-A, and correlated positively with Digit Span (backward) and Verbal Fluency Test scales, particularly on the left side. Compared with controls, patients with AD showed reduced metabolic connectivity between striatal executive subregions and the dorsolateral prefrontal cortex (DLPFC). LIMITATIONS: Our study was limited by small sample sizes and cross-sectional findings. CONCLUSION: Our findings show that patients with AD have impairments in the executive subregion of the striatum, and these deficits may be associated with a disconnection between the executive striatum and DLPFC, providing valuable insight into the pathogenesis of this disease.

Clinical profiles and ethnic heterogeneity of sporadic fatal insomnia.

BACKGROUND AND PURPOSE: This study was undertaken to elucidate the clinical profile of sporadic fatal insomnia (sFI), assess the similarities and differences between sFI and fatal familial insomnia (FFI), and evaluate the influence of ethnicity on the phenotype of sFI patients. METHODS: The data of sFI and FFI patients were retrieved from our case series and through literature review. The clinical and diagnostic features of sFI and FFI were compared, as were the phenotypes of Asian and Caucasian sFI patients. RESULTS: We identified 44 sFI and 157 FFI cases. The prevalence of sleep-related, neuropsychiatric, and autonomic symptoms among the sFI patients were 65.9%, 100.0%, and 43.2%, respectively. Compared to FFI, sFI exhibited longer disease duration and a higher proportion of neuropsychiatric symptoms, whereas FFI was characterized by a higher incidence of sleep-related and autonomic symptoms in the early stages of the disease or throughout its course. In addition, a higher proportion of the sFI patients showed hyperintensity on magnetic resonance imaging (MRI) and periodic sharp wave complexes on electroencephalography compared to the FFI patients, especially those presenting with pathological changes associated with MM2-cortical type sporadic Creutzfeldt-Jakob disease. The Asian sFI patients had a higher proportion of males and positivity for cerebrospinal fluid 14-3-3 protein, and fewer sleep-related symptoms compared to Caucasian sFI patients. The age at onset and duration of sFI differed between ethnic groups, but the difference failed to reach statistical significance. CONCLUSIONS: Despite its similarities to FFI, sFI is characterized by longer disease duration, higher proportion of neuropsychiatric symptoms, and hyperintensity on MRI, along with differences in the clinical characteristics based on ethnicity.

Altered metabolic connectivity within the limbic cortico-striato-thalamo-cortical circuit in presymptomatic and symptomatic behavioral variant frontotemporal dementia.

BACKGROUND: Behavioral variant frontotemporal dementia (bvFTD) is predominantly considered a dysfunction in cortico-cortical transmission, with limited direct investigation of cortical-subcortical transmission. Thus, we aimed to characterize the metabolic connectivity between areas of the limbic cortico-striato-thalamic-cortical (CSTC) circuit in presymptomatic and symptomatic bvFTD patients. METHODS: Thirty-three bvFTD patients and 33 unrelated healthy controls were recruited for this study. Additionally, six asymptomatic carriers of the MAPT P301L mutation were compared with 12 non-carriers who were all from the same family of bvFTD. Each participant underwent neuropsychological assessment, genetic testing, and a hybrid PET/MRI scan. Seed-based metabolic connectivity based on [18F]-fluorodeoxyglucose PET between the main components within the limbic CSTC circuit was explored according to the Oxford-GSK-Imanova Striatal Connectivity Atlas. RESULTS: BvFTD patients exhibited reduced metabolic connectivity between the relays in the limbic CSTC circuit, which included the frontal region (ventromedial prefrontal cortex, orbitofrontal cortex, rectus gyrus, and anterior cingulate cortex), the limbic striatum, and thalamus compared to controls. In the bvFTD patients, the involvement of the limbic CSTC circuit was associated with the severity of behavior disruption, as measured by the frontal behavior inventory, the disinhibition subscale, and the apathy subscale. Notably, asymptomatic MAPT carriers had weakened frontostriatal connectivity but enhanced striatothalamus and thalamofrontal connectivity within the limbic CSTC circuit compared with noncarriers. CONCLUSION: These findings suggested that aberrant metabolic connectivity within the limbic CSTC circuit is present in symptomatic and even asymptomatic stages of bvFTD. Thus, metabolic connectivity patterns could be used as a potential biomarker to detect the presymptomatic stage and track disease progression.

Dysfunction of the cardiac parasympathetic system in fatal familial insomnia: a heart rate variability study.

STUDY OBJECTIVES: Although sympathetic hyperactivity with preserved parasympathetic activity has been extensively recognized in fatal familial insomnia (FFI), the symptoms of parasympathetic nervous system failure observed in some patients are difficult to explain. Using heart rate variability (HRV), this study aimed to discover evidence of parasympathetic dysfunction in patients with FFI and the difference of parasympathetic activity between patients with FFI and Creutzfeldt-Jakob disease (CJD). METHODS: This study enrolled nine patients with FFI, eight patients with CJD and 18 healthy controls (HCs) from May 2013 to August 2020. All participants underwent a nocturnal video-polysomnography with lead II electrocardiography, and the data were analyzed using linear and nonlinear indices of HRV during both wake and sleep states. RESULTS: Compared to the HC and CJD groups, the FFI group had a continuously higher heart rate with a lower amplitude of oscillations. The low frequency (LF)/high frequency (HF) ratio and ratio of SD1 to SD2 and correlation dimension D2 (CD2) were significantly different in the FFI group compared to the HC group. The root mean square of successive differences (RMSSD), HF and SD1 in the FFI group were significantly lower than in the HC group. RMSSD, SD1, and CD2 in the FFI group were all significantly lower than in the CJD group. CONCLUSIONS: Cardiovascular dysautonomia in FFI may be partly attributable to parasympathetic abnormalities, not just sympathetic activation. HRV may be helpful as a noninvasive, quantitative, and effective autonomic function test for FFI diagnosis.

A novel truncating variant of SPAST associated with hereditary spastic paraplegia indicates a haploinsufficiency pathogenic mechanism.

Introduction: Hereditary spastic paraplegias (HSPs) are genetic neurodegenerative diseases. The most common form of pure HSP that is inherited in an autosomal dominant manner is spastic paraplegia type 4 (SPG4), which is caused by mutations in the SPAST gene. Different theories have been proposed as the mechanism underlying SPAST-HSP for different types of genetic mutations, including gain- and loss-of-function mechanisms. To better understand the mutation mechanisms, we performed genetic analysis and investigated a truncating SPAST variant that segregated with disease in one family. Objectives and methods: We described a pure HSP pedigree with family members across four generations. We performed genetic analysis and investigated a novel frameshift pathogenic variant (c.862_863dupAC, p. H289Lfs*27) in this family. We performed reverse transcription-polymerase chain reaction (RT-PCR), Sanger sequencing, and quantitative RT-PCR using total RNA from an Epstein-Barr virus-induced lymphoblastoid cell line produced from the proband. We also performed Western blotting on cell lysates to investigate if the protein expression of spastin is affected by this variant. Results: This variant (c.862_863dupAC, p. H289Lfs*27) co-segregated with pure HSP in this family and is not registered in any public database. Measurement of SPAST transcripts in lymphoblasts from the proband demonstrated a reduction of SPAST transcript levels through likely nonsense-mediated mRNA decay. Immunoblot analyses demonstrated a reduction of spastin protein expression levels in lymphoblasts. Conclusion: We report an SPG4 family with a novel heterozygous frameshift variant p.H289Lfs*27 in SPAST. Our study implies haploinsufficiency as the pathogenic mechanism for this variant and expands the known mutation spectrum of SPAST.

Involvement of striatal motoric subregions in familial frontotemporal dementia with parkinsonism harboring the C9orf72 repeat expansions.

The chromosome 9 open reading frame 72 (C9ORF72) has been proposed as the causative gene of frontotemporal dementia with parkinsonism (FTDP), but its pathophysiological mechanism of parkinsonism is poorly understood. To explore the roles of striatal motor subdivisions in the pathogenesis of parkinsonism resulting from C9ORF72 repeat expansions in the FTDP, two patients with FTDP from one pedigree and seventeen healthy controls were enrolled. The participants received clinical interviews, physical examinations, genetic testing, [18F]-fluorodeoxyglucose PET/MRI, and [18F]-dihydrotetrabenazine PET/CT. Voxel-wise and region of interest analysis were conducted with respect to gray matter volume, metabolism, and dopamine transport function between patients and controls, focusing on the motor part of the striatum according to the Oxford-GSK-Imanova Striatal Connectivity Atlas. Patient 1 presented with parkinsonism as the initial symptom, while patient 2 exhibited behavior disturbance as the first symptom, followed by parkinsonism within one year. Both patients had the hexanucleotide expansion detected in C9ORF72(>52 repeats). Gray matter volume atrophy, hypometabolism and dopamine dysfunction were observed in the motor areas of the striatum. Of the two patients, marked glucose hypometabolism within the striatal motor subregion was observed in patient 1, with corresponding gray matter atrophy. In addition, presynaptic dopaminergic integrity of patient 2 was deteriorated in the motor subregions which was consistent with gray matter atrophy. These findings imply that parkinsonism in FTDP may be associated with the degeneration and dopaminergic dysfunction of the striatal motor subregion, which might be attributed to C9orf72 repeat expansions.

Design, synthesis, and evaluation of 4(1H)-quinolinone and urea derivatives as KRASG12C inhibitors with potent antitumor activity against KRAS-mutant non-small cell lung cancer.

KRASG12C is the most prevalent KRAS mutation in non-small cell lung cancer (NSCLC) and has emerged as a promising therapeutic target. Herein, two series of novel 4(1H)-quinolinone and urea compounds were designed based on the reported KRASG12C inhibitor SH-9. Many compounds showed significantly growth inhibitory activity against human NSCLC cells with KRASG12C mutation in cell viability assays. Compound 20a exhibited an IC50 value of 0.5 µM in KRASG12C-mutant NCI-H358 cells with 21-fold selectivity over KRASWT NCI-H2228 cells. LC-MS analysis indicated that compounds 14c, 14h and 20a covalently bound to KRASG12C rather than KRASWT. Moreover, these compounds could remarkably trap KRASG12C in its inactive state by blocking SOS1-mediated GDP/GTP exchange. Furthermore, treatment of NCI-H358 but not NCI-H2228 cells with 20a dose-dependently reduced the phosphorylation of KRAS downstream effectors ERK and AKT. Importantly, 20a significantly inhibited tumor growth in NCI-H358 xenograft models by suppressing KRASG12C signalling. These results indicate that 20a is a promising candidate worthy of further investigation.

A longitudinal 18F-FDG PET/MRI study in asymptomatic stage of genetic Creutzfeldt-Jakob disease linked to G114V mutation.

BACKGROUND: Pathogenic prion protein may start to deposit in some brain regions and cause functional alterations in the asymptomatic stage in Creutzfeldt-Jakob disease. The study aims to determine the trajectory of the brain metabolic changes for prion protein diseases at the preclinical stage. METHODS: At baseline, we enrolled five asymptomatic PRNP G114V mutation carriers, six affected genetic PRNP E200K CJD patients and 23 normal controls. All participants completed clinical, diffusion-weighted imaging (DWI) and 18F fluorodeoxyglucose-positron emission tomography (18F-FDG-PET) examinations. Longitudinal follow-up was completed in five asymptomatic mutation carriers. We set three-time points to identify the changing trajectory in the asymptomatic carriers group including baseline, 2-year and 4-year follow-up. RESULTS: At baseline, DWI signals, the cerebral glucose standardized uptake value rate ratio (SUVR) and clinical status in 5 asymptomatic cases were normal. At the follow-up period, mild hypometabolism on PET images was found in asymptomatic carriers without any DWI abnormal signal. Further group quantitatively analysis showed hypometabolic brain regions in the asymptomatic genetic CJD group were in the insula, frontal, parietal, and temporal lobes in 4-year follow-up. The SUVR changing trajectories of all asymptomatic cases were within the range between the normal controls and affected patients. Notably, the SUVR of one asymptomatic individual whose baseline age was older showed a rapid decline at the last follow-up. CONCLUSIONS: Our study illustrates that the neurodegenerative process associated with genetic CJD may initiate before the clinical presentation of the disease.

Thalamic-insomnia phenotype in E200K Creutzfeldt-Jakob disease: A PET/MRI study.

BACKGROUND: Insomnia and thalamic involvement were frequently reported in patients with genetic Creutzfeldt-Jakob disease (gCJD) with E200K mutations, suggesting E200K might have discrepancy with typical sporadic CJD (sCJD). The study aimed to explore the clinical and neuroimage characteristics of genetic E200K CJD patients by comprehensive neuroimage analysis. METHODS: Six patients with gCJD carried E200K mutation on Prion Protein (PRNP) gene, 13 patients with sporadic CJD, and 22 age- and sex-matched normal controls were enrolled in the study. All participants completed a hybrid positron emission tomography/magnetic resonance imaging (PET/MRI) examination. Signal intensity on diffusion-weighted imaging (DWI) and metabolism on PET were visually rating analyzed, statistical parameter mapping analysis was performed on PET and 3D-T1 images. Clinical and imaging characteristics were compared between the E200K, sCJD, and control groups. RESULTS: There was no group difference in age or gender among the E200K, sCJD, and control groups. Insomnia was a primary complaint in patients with E200K gCJD (4/2 versus 1/12, p = 0.007). Hyperintensity on DWI and hypometabolism on PET of the thalamus were observed during visual rating analysis of images in patients with E200K gCJD. Gray matter atrophy (uncorrected p < 0.001) and hypometabolism (uncorrected p < 0.001) of the thalamus were more pronounced in patients with E200K gCJD. CONCLUSION: The clinical and imaging characteristics of patients with gCJD with PRNP E200K mutations manifested as a thalamic-insomnia phenotype. PET is a sensitive approach to help identify the functional changes in the thalamus in prion disease.

Genetic prion diseases presenting as frontotemporal dementia: clinical features and diagnostic challenge.

BACKGROUND: To elucidate the clinical and ancillary features of genetic prion diseases (gPrDs) presenting with frontotemporal dementia (FTD) to aid early identification. METHODS: Global data of gPrDs presenting with FTD caused by prion protein gene mutations were collected from literature review and our records. Fifty-one cases of typical FTD and 136 cases of prion diseases admitted to our institution were included as controls. Clinical and ancillary data of the different groups were compared. RESULTS: Forty-nine cases of gPrDs presenting with FTD were identified. Compared to FTD or prion diseases, gPrDs presenting with FTD were characterized by earlier onset age (median 45 vs. 61/60 years, P < 0.001, P < 0.001) and higher incidence of positive family history (81.6% vs. 27.5/13.2%, P < 0.001, P < 0.001). Furthermore, GPrDs presenting with FTD exhibited shorter duration (median 5 vs. 8 years) and a higher rate of parkinsonism (63.7% vs. 9.8%, P < 0.001), pyramidal signs (39.1% vs. 7.8%, P = 0.001), mutism (35.9% vs. 0%, P < 0.001), seizures (25.8% vs. 0%, P < 0.001), myoclonus (22.5% vs. 0%, P < 0.001), and hyperintensity on MRI (25.0% vs. 0, P < 0.001) compared to FTD. Compared to prion diseases, gPrDs presenting with FTD had a longer duration of symptoms (median 5 vs. 1.1 years, P < 0.001), higher rates of frontotemporal atrophy (89.7% vs. 3.3%, P < 0.001), lower rates of periodic short-wave complexes on EEG (0% vs. 30.3%, P = 0.001), and hyperintensity on MRI (25.0% vs. 83.0%, P < 0.001). The frequency of codon 129 Val allele in gPrDs presenting with FTD was significantly higher than that reported in the literature for gPrDs in the Caucasian and East Asian populations (33.3% vs. 19.2%/8.0%, P = 0.005, P < 0.001). CONCLUSIONS: GPrDs presenting with FTD are characterized by early-onset, high incidence of positive family history, high frequency of the Val allele at codon 129, overlapping symptoms with prion disease and FTD, and ancillary features closer to FTD. PRNP mutations may be a rare cause in the FTD spectrum, and PRNP genotyping should be considered in patients with these features.

Specific structuro-metabolic pattern of thalamic subnuclei in fatal familial insomnia: A PET/MRI imaging study.

BACKGROUND: Dysfunction of the thalamus has been proposed as a core mechanism of fatal familial insomnia. However, detailed metabolic and structural alterations in thalamic subnuclei are not well documented. We aimed to address the multimodal structuro-metabolic pattern at the level of the thalamic nuclei in fatal familial insomnia patients, and investigated the clinical presentation of primary thalamic alterations. MATERIALS AND METHODS: Five fatal familial insomnia patients and 10 healthy controls were enrolled in this study. All participants underwent neuropsychological assessments, polysomnography, electroencephalogram, and cerebrospinal fluid tests. MRI and fluorodeoxyglucose PET were acquired on a hybrid PET/MRI system. Structural and metabolic changes were compared using voxel-based morphometry analyses and standardized uptake value ratio analyses, focusing on thalamic subnuclei region of interest analyses. Correlation analysis was conducted between gray matter volume and metabolic decrease ratios, and clinical features. RESULTS: The whole-brain analysis showed that gray matter volume decline was confined to the bilateral thalamus and right middle temporal pole in fatal familial insomnia patients, whereas hypometabolism was observed in the bilateral thalamus, basal ganglia, and widespread cortices, mainly in the forebrain. In the regions of interest analysis, gray matter volume and metabolism decreases were prominent in bilateral medial dorsal nuclei, anterior nuclei, and the pulvinar, which is consistent with neuropathological and clinical findings. A positive correlation was found between gray matter volume and metabolic decrease ratios. CONCLUSIONS: Our study revealed specific structuro-metabolic pattern of fatal familial insomnia that demonstrated the essential roles of medial dorsal nuclei, anterior nuclei, and pulvinar, which may be a potential biomarker in diagnosis. Also, primary thalamic subnuclei alterations may be correlated with insomnia, neuropsychiatric, and autonomic symptoms sparing primary cortical involvement.

Proposal of new diagnostic criteria for fatal familial insomnia.

BACKGROUND: The understanding of fatal familial insomnia (FFI), a rare neurodegenerative autosomal dominant prion disease, has improved in recent years as more cases were reported. This work aimed to propose new diagnostic criteria for FFI with optimal sensitivity, specificity, and likelihood ratio. METHODS: An international group of experts was established and 128 genetically confirmed FFI cases and 281 non-FFI prion disease controls are enrolled in the validation process. The new criteria were proposed based on the following steps with two-round expert consultation: (1) Validation of the 2018 FFI criteria. (2) Diagnostic item selection according to statistical analysis and expert consensus. (3) Validation of the new criteria. RESULTS: The 2018 criteria for possible FFI had a sensitivity of 90.6%, a specificity of 83.3%, with a positive likelihood ratio (PLR) of 5.43, and a negative likelihood ratio (NLR) of 0.11; and the probable FFI criteria had a sensitivity of 83.6%, specificity of 92.9%, with a PLR of 11.77, and a NLR of 0.18. The new criteria included more specific and/or common clinical features, two exclusion items, and summarized a precise and flexible diagnostic hierarchy. The new criteria for possible FFI had therefore reached a better sensitivity and specificity (92.2% and 96.1%, respectively), a PLR of 23.64 and a NLR of 0.08, whereas the probable FFI criteria showed a sensitivity of 90.6%, a specificity of 98.2%, with a PLR of 50.33 and a NLR of 0.095. CONCLUSIONS: We propose new clinical diagnostic criteria for FFI, for a better refining of the clinical hallmarks of the disease that ultimately would help an early recognition of FFI and a better differentiation from other prion diseases.

Reconfigured metabolism brain network in asymptomatic microtubule-associated protein tau mutation carriers: a graph theoretical analysis.

BACKGROUND: Studies exploring topological properties of the metabolic network during the presymptomatic stage of genetic frontotemporal dementia (FTD) are scarce. However, such knowledge is important for understanding brain function and disease pathogenesis. Therefore, we aimed to explore FTD-specific patterns of metabolism topology reconfiguration in microtubule-associated protein tau (MAPT) mutation carriers before the onset of symptoms. METHODS: Six asymptomatic carriers of the MAPT P301L mutation were compared with 12 non-carriers who all belonged to the same family of FTD. For comparison, we included 32 behavioral variant FTD (bvFTD) patients and 33 unrelated healthy controls. Each participant underwent neuropsychological assessments, genetic testing, and a hybrid positron emission tomography (PET)/magnetic resonance imaging (MRI) scan. Voxel-wise gray matter volumes and standardized uptake value ratios were calculated and compared for structural MRI and fluorodeoxyglucose (FDG)-PET, separately. The sparse inverse covariance estimation method (SICE) was applied to topological properties and metabolic connectomes of brain functional networks derived from 18F-FDG PET/MRI data. Independent component analysis was used to explore the metabolic connectivity of the salience (SN) and default mode networks (DMN). RESULTS: The asymptomatic MAPT carriers performed normal global parameters of the metabolism network, whereas bvFTD patients did not. However, we revealed lost hubs in the ventromedial prefrontal, orbitofrontal, and anterior cingulate cortices and reconfigured hubs in the anterior insula, precuneus, and posterior cingulate cortex in asymptomatic carriers compared with non-carriers, which overlapped with the comparisons between bvFTD patients and controls. Similarly, significant differences in local parameters of these nodes were present between asymptomatic carriers and non-carriers. The reduction in the connectivity of lost hub regions and the enhancement of connectivity between reconfigured hubs and components of the frontal cortex were marked during the asymptomatic stage. Metabolic connectivity within the SN and DMN was enhanced in asymptomatic carriers compared with non-mutation carriers but reduced in bvFTD patients relative to controls. CONCLUSIONS: Our findings showed that metabolism topology reconfiguration, characterized by the earliest involvement of medial prefrontal areas and active compensation in task-related regions, was present in the presymptomatic phase of genetic FTD with MAPT mutation, which may be used as an imaging biomarker of increased risk of FTD.