Self-assembly of differentiated dental pulp stem cells facilitates spheroid human dental organoid formation and prevascularization.

BACKGROUND: The self-assembly of solid organs from stem cells has the potential to greatly expand the applicability of regenerative medicine. Stem cells can self-organise into microsized organ units, partially modelling tissue function and regeneration. Dental pulp organoids have been used to recapitulate the processes of tooth development and related diseases. However, the lack of vasculature limits the utility of dental pulp organoids. AIM: To improve survival and aid in recovery after stem cell transplantation, we demonstrated the three-dimensional (3D) self-assembly of adult stem cell-human dental pulp stem cells (hDPSCs) and endothelial cells (ECs) into a novel type of spheroid-shaped dental pulp organoid in vitro under hypoxia and conditioned medium (CM). METHODS: During culture, primary hDPSCs were induced to differentiate into ECs by exposing them to a hypoxic environment and CM. The hypoxic pretreated hDPSCs were then mixed with ECs at specific ratios and conditioned in a 3D environment to produce prevascularized dental pulp organoids. The biological characteristics of the organoids were analysed, and the regulatory pathways associated with angiogenesis were studied. RESULTS: The combination of these two agents resulted in prevascularized human dental pulp organoids (Vorganoids) that more closely resembled dental pulp tissue in terms of morphology and function. Single-cell RNA sequencing of dental pulp tissue and RNA sequencing of Vorganoids were integrated to analyse key regulatory pathways associated with angiogenesis. The biomarkers forkhead box protein O1 and fibroblast growth factor 2 were identified to be involved in the regulation of Vorganoids. CONCLUSION: In this innovative study, we effectively established an in vitro model of Vorganoids and used it to elucidate new mechanisms of angiogenesis during regeneration, facilitating the development of clinical treatment strategies.

Larger corpus callosum and reduced orbitofrontal cortex homotopic connectivity in codeine cough syrup-dependent male adolescents and young adults.

OBJECTIVES: To characterize interhemispheric functional and anatomical connectivity and their relationships with impulsive behaviour in codeine-containing cough syrup (CCS)-dependent male adolescents and young adults. METHODS: We compared volumes of corpus callosum (CC) and its five subregion and voxel-mirrored homotopic functional connectivity (VMHC) in 33 CCS-dependent male adolescents and young adults and 38 healthy controls, group-matched for age, education and smoking status. Barratt impulsiveness scale (BIS.11) was used to assess participant impulsive behaviour. Abnormal CC subregions and VMHC revealed by group comparison were extracted and correlated with impulsive behaviour and duration of CCS use. RESULTS: We found selective increased mid-posterior CC volume in CCS-dependent male adolescents and young adults and detected decreased homotopic interhemispheric functional connectivity of medial orbitofrontal cortex (OFC). Moreover, impairment of VMHC was associated with the impulsive behaviour and correlated with the duration of CCS abuse in CCS-dependent male adolescents and young adults. CONCLUSIONS: These findings reveal CC abnormalities and disruption of interhemispheric homotopic connectivity in CCS-dependent male adolescents and young adults, which provide a novel insight into the impact of interhemispheric disconnectivity on impulsive behaviour in substance addiction pathophysiology. KEY POINTS: • CCS-dependent individuals (patients) had selective increased volumes of mid-posterior corpus callosum • Patients had attenuated interhemispheric homotopic FC (VMHC) of bilateral orbitofrontal cortex • Impairment of VMHC correlated with impulsive behaviour in patients • Impairment of VMHC correlated with the CCS duration in patients.

The impulsivity behavior is correlated with prefrontal cortex gray matter volume reduction in heroin-dependent individuals.

PURPOSE: Chronic exposure to heroin induced cerebral structural abnormalities may underlie heroin-related behaviors. The aim of this study was to: (1) identify cerebral structural abnormalities in heroin-dependent individuals (HDIs) by an automated and unbiased morphometric technique. (2) Define the correlation between these cerebral structural abnormalities and the impulsivity characteristic in HDIs. METHODS: 24 HDIs and 24 control subjects were completed with (1) high resolution structural magnetic resonance imaging scanning and analysis of gray matter volume using voxel-based morphometry implemented in Statistical Parametric Mapping and (2) a Chinese translation Barratt Impulsiveness Scale-11 questionnaire survey. Differences in regional gray matter volume were tested using an analysis of covariance model, co-varying for global gray matter and age. Statistical maps were set at p<0.05, corrected for multiple comparisons. The abnormal brain regions were correlated with the duration of heroin use and impulsivity scores. RESULTS: After adjusting for effects of age and total gray matter volume, cortical gray matter volume in the bilateral medial prefrontal cortex, bilateral dorsal lateral prefrontal cortex, and right fusiform cortex were significantly reduced in HDIs. Moreover, the gray matter volume in prefrontal cortex that showed group differences was negatively correlated with the duration of heroin use and negatively correlated with the impulsivity characteristic in HDIs. CONCLUSION: These findings reveal the prefrontal cortex was impaired in HDIs, meanwhile, indicate the changes in gray matter volume are relating to the duration of heroin use and the impulsivity characteristic of the HDIs.

Primary haemangiopericytoma outside muscle cone in fossa orbitalis: a case report and review.

PURPOSE: Orbital haemangiopericytoma (HPC) is a rare tumor with great histological variability and unpredictable clinical and biological behavior. The precise cell type origin is uncertain. METHOD: A case report is provided. RESULTS: A 24-year-old male patient visited an ophthalmologist because of proptosis, strabismus, and movement limitation of the right eye one year ago. These symptoms worsened rapidly. Histopathology, MRI methods and microscopy coil were applied to study the features of HPC. The tumor was removed and the histological examination revealed that it was a primary HPC of the orbit. CONCLUSION: MRI determined the size, location, circumscription, morphological detail, growth pattern, and relationship between masses and surrounding tissues. The genesis location of this HPC was rare, and its internal morphological characters were different from cases reported in the literature. The new type of microscope showed more details of tumor MR image characters objectively.

Regional homogeneity changes in heroin-dependent individuals: resting-state functional MR imaging study.

PURPOSE: To identify heroin-related modulations of neural activity in the resting state in heroin-dependent individuals (HDIs) by using resting-state functional magnetic resonance (MR) imaging and a regional homogeneity method and to investigate whether these changes of neural activity can be related to duration of heroin use and to decision-making deficits in HDIs. MATERIALS AND METHODS: This prospective study was approved by the appropriate ethics committee, and written informed consent was obtained from each participant. Thirty-one HDIs receiving methadone-maintained treatment and 24 control subjects participated. Resting-state functional MR imaging was performed by using a gradient-echo echo-planar imaging sequence. Regional homogeneity was calculated by using software. Voxel-based analysis of the regional homogeneity maps between control and HDI groups was performed with two-sample t tests by using software. Statistical maps were set at P less than .05 and were corrected for multiple comparisons. The Iowa gambling task (IGT) was used to assess participant decision making during uncertainty. Abnormal clusters revealed by group comparison were extracted and correlated with behavioral performance at the IGT and with duration of heroin use. RESULTS: Regional homogeneity was diminished in the bilateral medial orbitofrontal cortex (OFC), bilateral dorsal medial thalamus, bilateral cuneus, and lingual gyrus in HDIs compared with control subjects. There were negative correlations between mean regional homogeneity in the medial OFC, bilateral cuneus, and lingual gyrus and duration of heroin use. There was a positive correlation between mean regional homogeneity in the medial OFC and performance level at the IGT. CONCLUSION: The present study reveals resting-state abnormalities in HDIs that may lead to further improvement of the understanding of the neural substrates of cognitive impairment in HDIs.

Amplitude low-frequency oscillation abnormalities in the heroin users: a resting state fMRI study.

Functional neuroimaging studies have revealed abnormal functional organization of the heroin users' brain, including reward circuit, cognitive control circuit, memory circuit, motivation and salience evaluation circuits and so on. In the current study, we aimed to explore the functional changes in the regional brain of heroin users using the amplitude of low-frequency oscillations in the Blood Oxygenation Level Dependent (BOLD) signals. With fMRI data acquired during resting state from 24 chronic heroin users (all subjects were being treated with methadone) and 24 non-addicted controls, we investigated addiction related altered in the amplitude low-frequency fluctuate (ALFF) between the two groups. Compared with controls, we found that heroin addicts had decreased ALFF in the bilateral dorsal anterior cingulate cortex (dACC), bilateral medial orbit frontal cortex (mOFC), left dorsal lateral prefrontal cortex (dlPFC), left middle temporal gyrus, left inferior temporal gyrus, posterior cingulate cortex and left cuneus as well as increased ALFF in the bilateral angular gyrus, bilateral precuneus, bilateral supramarginal gyrus, left post cingulate cortex and left middle frontal gyrus. Moreover, we also found that the increased ALFF in the bilateral parietal lobe had a significantly positive correlation with the methadone does, thus we inferred that the reduced ALFF may due to heroin consumption, nevertheless, the increased ALFF in the bilateral parietal lobe may have resulted from the methadone treatment. This resting-state fMRI study suggests that the changed spontaneous neuronal activity of these regions may be implicated in the underlying pathophysiology of heroin addicts.

[Correlation analysis between multi-slice CT perfusion imaging and microvessel density in ovarian tumors].

OBJECTIVE: To analyze the correlation between the perfusion data and microvessel density (MVD) in ovarian tumors, and investigate the hemodynamic features of the tumors in terms of anatomy and functional CT imaging. METHODS: Six patients with surgically confirmed benign ovarian tumors and 6 with malignant ovarian tumors underwent multi-slice CT perfusion imaging to acquire the perfusion parameters including perfusion, PEI, TTP, BV peak enhancement image(PEI), time to peak(TTP) and blood volume(BV). The tumors were stained and counted by Immunohistochemical staining of the microvessels in the tumor was performed to detect the MVD. RESULTS: s The time-density curves of the benign ovarian tumors increased slowly, reaching the peak at 40 s; the curves of the malignant tumors rose rapidly and continuously and reached the peak at 25 s. The differences in the perfusion data (PEI, TTP, BV) were statistically significant between the benign and malignant tumors (P<0.05). The MVD of the malignant tumors was significantly greater than that of the benign tumors (P<0.05). The mean BV of the malignant ovarian tumor was positively correlated to MVD (r=0.786, P<0.05). CONCLUSION: Multi-slice spiral CT perfusion imaging can provide accurate enhancement data of the ovarian tumors and helps in the diagnosis and differential diagnosis of the ovarian tumors by presenting the changes of the hemodynamic features in the tumors.

[Atypical magnetic resonance imaging vs pathological findings of leiomyoma in the female reproductive system].

OBJECTIVE: To investigate magnetic resonance imaging (MRI) findings of the atypical leiomyoma in the female reproductive system in comparison with the pathological features of the neoplasms. METHODS: A retrospective analysis of the MRI findings and the pathological features was conducted in 24 cases of atypical leiomyoma involving the female reproductive system. RESULTS: Atypical leiomyomas were displayed by MRI as solid tumor mass surrounded by cystic degeneration, pseudotumors, or solid mass with homogeneous signal intensity. Intrauterine lesions were found in 19 cases, involving the subserosal layer (n=11), intramural region (n=4), broad ligament (n=3), cervix (n=2), submucous layer (n=2), vagina (n=1), and the ovary (n=1). Except for two cases with submucous lesions shown as solid mass, all the cases had lesions appearing as solid cystic mass, whose solid part showed hypo or isointense signals on T1WI and moderate hyperintense signals on T2WI, with heterogeneous enhancement after contrast agent injection. Tumor cell and interstitial cell swelling, vascular hyalinosis, hyalinosis, myxoedema, cystic degeneration, and hemorrhage were found in the lesions. CONCLUSION: Leiomyoma can occur at almost any site in the female reproductive system, and atypical leiomyoma usually are shown as solid cystic mixed mass in the pelvic cavity. Evaluation of the relationship between the solid mass and cystic portion and observation for the presence of low signal on T2WI may help in the diagnosis of atypical leiomyoma.