The microstructural change of the brain and its clinical severity association in pediatric Tourette syndrome patients

BACKGROUND

Gilles de la Tourette syndrome (GTS) is a prevalent pediatric neurological disorder. Most studies point to abnormalities in the cortico-striato-thalamocortical (CSTC) circuits. Neuroimaging studies have shown GTS's extensive impact on the entire brain. However, due to participant variability and potential drug and comorbidity impact, the results are inconsistent. To mitigate the potential impact of participant heterogeneity, we excluded individuals with comorbidities or those currently undergoing medication treatments. Based on the hypothesis of abnormality within the CSTC circuit, we investigated microstructural changes in white matter using diffusion spectrum imaging (DSI). This study offers the first examination of microstructural changes in treatment-naïve pediatric patients with pure GTS using diffusion spectrum imaging.

METHODS

This single-center prospective study involved 30 patients and 30 age- and gender-matched healthy volunteers who underwent sagittal T1-weighted MRI and DSI. We analyzed generalized fractional anisotropy, mean diffusivity, axial diffusivity, and radial diffusivity.

RESULTS

No significant differences were observed in mean diffusivity and axial diffusivity values between the two groups. However, the patient group exhibited significantly higher generalized fractional anisotropy values in the right frontostriatal tract of the dorsolateral prefrontal cortex, the right frontostriatal tract of the precentral gyrus, and bilateral thalamic radiation of the dorsolateral prefrontal cortex. Additionally, the generalized fractional anisotropy value of the right frontostriatal tract of the precentral gyrus is inversely correlated with the total tic severity scores at the most severe condition.

CONCLUSION

Treatment-naïve pediatric GTS patients demonstrated increased connectivity within the CSTC circuit as per diffusion spectrum imaging, indicating possible CSTC circuit dysregulation. This finding could also suggest a compensatory change. It thus underscores the necessity of further investigation into the fundamental pathological changes in GTS. Nevertheless, the observed altered connectivity in GTS patients might serve as a potential target for therapeutic intervention.

Brain Age Difference at Baseline Predicts Clinical Dementia Rating Change in Approximately Two Years

BACKGROUND

The Clinical Dementia Rating (CDR) has been widely used to assess dementia severity, but it is limited in predicting dementia progression, thus unable to advise preventive measures to those who are at high risk.

OBJECTIVE

Predicted age difference (PAD) was proposed to predict CDR change.

METHODS

All diffusion magnetic resonance imaging and CDR scores were obtained from the OASIS-3 databank. A brain age model was trained by a machine learning algorithm using the imaging data of 258 cognitively healthy adults. Two diffusion indices, i.e., mean diffusivity and fractional anisotropy, over the whole brain white matter were extracted to serve as the features for model training. The validated brain age model was applied to a longitudinal cohort of 217 participants who had CDR = 0 (CDR0), 0.5 (CDR0.5), and 1 (CDR1) at baseline. Participants were grouped according to different baseline CDR and their subsequent CDR in approximately 2 years of follow-up. PAD was compared between different groups with multiple comparison correction.

RESULTS

PADs were significantly different among participants with different baseline CDRs. PAD in participants with relatively stable CDR0.5 was significantly smaller than PAD in participants who had CDR0.5 at baseline but converted to CDR1 in the follow-up. Similarly, participants with relatively stable CDR0 had significantly smaller PAD than those who were CDR0 at baseline but converted to CDR0.5 in the follow-up.

CONCLUSION

Our results imply that PAD might be a potential imaging biomarker for predicting CDR outcomes in patients with CDR0 or CDR0.5.

Microstructural differences in white matter tracts across middle to late adulthood: a diffusion MRI study on 7167 UK Biobank participants

White matter fiber tracts demonstrate heterogeneous vulnerabilities to aging effects. Here, we estimated age-related differences in tract properties using UK Biobank diffusion magnetic resonance imaging data of 7167 47- to 76-year-old neurologically healthy people (3368 men and 3799 women). Tract properties in terms of generalized fractional anisotropy, axial diffusivity, radial diffusivity, and mean diffusivity were sampled on 76 fiber tracts; for each tract, age-related differences were estimated by fitting these indices against age in a linear model. This cross-sectional study demonstrated 4 age-difference patterns. The dominant pattern was lower generalized fractional anisotropy and higher axial diffusivity, radial diffusivity, and mean diffusivity with age, constituting 45 of 76 tracts, mostly involving the association, projection, and commissure fibers connecting the prefrontal lobe. The other 3 patterns constituted only 14 tracts, with atypical age differences in diffusion indices, and mainly involved parietal, occipital, and temporal cortices. By analyzing the large volume of diffusion magnetic resonance imaging data available from the UK Biobank, the study has provided a detailed description of heterogeneous age-related differences in tract properties over the whole brain which generally supports the myelodegeneration hypothesis.

Associations between serum total bilirubin levels and functional dependence in the elderly

BACKGROUND

Many studies support the role of bilirubin as a cytoprotector in chronic inflammatory diseases, such as stroke and atherosclerosis.

AIM

To investigate the relationship between serum total bilirubin levels and functional dependence in older adults.

METHODS

Data from the National Health and Nutrition Examination Survey (1999-2002) pertaining to 2235 old adults were analysed. All participants had given a household interview, providing information of five major domains on self-reported functional status (activities of daily living, instrumental activities of daily living, leisure and social activities, lower extremity mobility and general physical activities), had completed serum total bilirubin measurement, and a questionnaire regarding personal health. Poor performance was defined as experiencing difficulty with one or more items in a given domain. Functional dependence was defined as having three or more poor performances in the five major domains. Multiple logistic regression was performed together with quartile-based stratified odds ratio (OR) comparison and trend tests.

RESULTS

The OR of functional dependence for each standard deviation increment in the serum total bilirubin level was 0.56 (P = 0.002). After additional adjustment, the inverse association remained essentially unchanged. In quartile-based analysis, participants with higher quartiles of serum total bilirubin tended to have lower ORs of functional dependence. The trends of lower likelihood of functional dependence across increasing quartiles of the serum total bilirubin level were statistically significant (P < 0.05 for all trends).

CONCLUSIONS

Higher serum total bilirubin levels were associated with lower likelihood of functional dependence in older adults.

Relationship between dialysis adequacy and quality of life in long-term peritoneal dialysis patients

OBJECTIVE

The purpose of this study was to compare quality of life (QOL) between peritoneal dialysis (PD) patients with adequate and inadequate total solute clearance (TSC). We also tried to determine the relationship between QOL and TSC.

DESIGN

A cross-sectional study design was used in which QOL was evaluated and compared between PD patients with adequate and inadequate TSC.

SETTING

The PD unit of a university teaching hospital.

PATIENTS

Sixty-seven patients were recruited, 38 on continuous ambulatory PD and 29 on continuous cyclerassisted PD.

METHODS

Patients were divided into adequate and inadequate groups, based on the results of either total urea clearance (Kt/Vurea) or total creatinine clearance (weekly CCr). The demographic data, dialysis variables, and clinical parameters of these patients were all collected. QOL was evaluated using the SF-36 questionnaire, which contains eight domains and is a comprehensive and validated instrument for QOL evaluation. QOL of patients in adequate and inadequate groups was compared. The relationship between QOL and TSC was also examined.

RESULTS

Among patients grouped by Kt/Vurea, patients in the adequate group had significantly higher scores in two domains of the SF-36, that is, physical and emotional role functioning, than did those in the inadequate group. The total SF-36 scores were positively correlated with Kt/Vurea when all patients were pooled together. However, among patients grouped by weekly CCr, there was no significant difference in any of the eight domains of the SF-36 between patients in the adequate and inadequate groups. No correlation was found between the total SF-36 scores and weekly CCr.

CONCLUSION

Our study had two important findings: First, PD patients with adequate total solute clearance, based on Kt/Vurea and not on weekly CCr, had a better QOL. Second, Kt/Vurea is better correlated with QOL than weekly CCr. These findings suggest that Kt/Vurea is a better parameter for the clinical evaluation of total solute clearance from the viewpoint of QOL.

Induction of apoptosis by hibiscus protocatechuic acid in human leukemia cells via reduction of retinoblastoma (RB) phosphorylation and Bcl-2 expression

Hibiscus protocatechuic acid (PCA), a phenolic compound isolated from the dried flower of Hibiscus sabdariffa L. (Malvaceae), demonstrated antioxidant and antitumor promotion effects in our previous study. In the present study, Hibiscus PCA was found to inhibit the survival of human promyelocytic leukemia HL-60 cells in a concentration- and time-dependent manner. The study revealed that HL-60 cells underwent internucleosomal DNA fragmentation and morphological changes characteristic of apoptosis after a 9-hr treatment with Hibiscus PCA (2 mM). Flow cytometric analysis of the DNA content of cells treated with PCA for 12 hr showed that the cells were distributed mainly in the hypodiploid phase (apoptotic peak, 46.7%), less in the G(1) (34.2%) and S phase (14.0%), and few in the G(2)/M phase (5.1%). Moreover, PCA treatment caused an increase in the level of hypophosphorylated retinoblastoma (RB; 180% of control at the 6-hr time point) and, on the contrary, a decline in hyperphosphorylated RB. A rapid loss of RB was observed when the treatment period was extended. Further studies showed that Hibiscus PCA application reduced Bcl-2 protein expression to 47%, and increased Bax protein expression to 181% after 1.5 hr as compared with time 0. Overexpression of Bcl-2 in HL-60 cells delayed the occurrence of Hibiscus PCA-induced apoptosis. These data suggest that Hibiscus PCA is an apoptosis inducer in human leukemia cells, and that RB phosphorylation and Bcl-2 protein may play a crucial role in the early stage.

Ticlopidine-induced aplastic anemia: report of three Chinese patients and review of the literature

In this study, three Chinese patients with ticlopidine-induced aplastic anemia were reported and another 13 patients in the English literature were reviewed. We attempted to find underlying similarities, evaluate the risk factors, and identify appropriate treatment for this complication. All but one of the patients were over 60 years old, and the 6 who died were all older than 65. Therefore, old age may be a risk factor for developing this complication. Agranulocytosis occurred 3-20 weeks after initiation of ticlopidine, so frequent examination of white cell count during treatment is recommended. There seemed to be no direct correlation between the dose or duration used and the severity of bone marrow suppression. Treatment for ticlopidine-induced aplastic anemia with colony-stimulating factors seemed to have little effect. The fact that 5 of the 6 patients who received concurrent calcium channel blockers died, should alert clinicians to be more cautious when using these two drugs simultaneously.

Microbiologic and histologic diagnosis of histoplasmosis in Taiwan

Histoplasmosis is one of the most common opportunistic fungal infections in immunocompromised patients in endemic areas. We report the first two microbiologically documented cases of histoplasmosis in Taiwan. The first patient, with acquired immunodeficiency syndrome and a depleted CD4+ lymphocyte count, presented with a history of prolonged fever, papular skin rashes, pancytopenia and elevation of liver enzymes. He was diagnosed and treated initially for systemic toxoplasmosis, but the microbiologic and pathologic findings of the autopsied specimens disclosed disseminated infection caused by Histoplasma capsulatum. The second patient, an elderly man receiving corticosteroids for adrenal insufficiency, manifested with laryngeal histoplasmosis and was successfully treated with ketoconazole.

High-sensitivity intrinsic fiber-optic Fabry-Perot pressure sensor

A new configuration for a pressure sensor in which the motion of a diaphragm produces strain in a fiber Fabry-Perot interferometer (FFPI) is described. The single-mode fiber containing the interferometer is bonded at one end to the stainless-steel diaphragm. The fiber is also attached beyond the interferometer to the sensor housing in such a manner that it is always under tension and experiences a strain in proportion to the deflection of the diaphragm. An analysis relating the expected interferometer phase change to pressure is presented, and the dynamic response of the FFPI sensor to pressure changes produced by an air pump is in good agreement with that measured with a conventional pressure sensor.