Cognitive impairment associated with cerebellar volume loss in spinocerebellar ataxia type 3

BACKGROUND

Many neuroscience and neurology studies have forced a reconsideration of the traditional motor-related scope of cerebellar function, which has now expanded to include various cognitive functions. Spinocerebellar ataxia type 3 (SCA3; the most common hereditary ataxia) is neuropathologically characterized by cerebellar atrophy and frequently presents with cognitive impairment.

OBJECTIVE

To characterize cognitive impairment in SCA3 and investigate the cerebellum-cognition associations.

METHODS

This prospective, cross-sectional cohort study recruited 126 SCA3 patients and 41 healthy control individuals (HCs). Participants underwent a brain 3D T1-weighted images as well as neuropsychological tests. Voxel-based morphometry (VBM) and region of interest (ROI) approaches were performed on the 3D T1-weighted images. CERES was used to automatically segment cerebellums. Patients were grouped into cognitively impaired (CI) and cognitively preserved (CP), and clinical and MRI parameters were compared. Multivariable regression models were fitted to examine associations between cerebellar microstructural alterations and cognitive domain impairments.

RESULTS

Compared to HCs, SCA3 patients showed cognitive domain impairments in information processing speed, verbal memory, executive function, and visuospatial perception. Between CI and CP subgroups, the CI subgroup was older and had lower education, as well as higher severity scores. VBM and ROI analyses revealed volume loss in cerebellar bilateral lobule VI, right lobule Crus I, and right lobule IV of the CI subgroup, and all these cerebellar lobules were associated with the above cognitive domain impairments.

CONCLUSIONS

Our findings demonstrate the multiple cognitive domain impairments in SCA3 patients and indicate the responsible cerebellar lobules for the impaired cognitive domain(s).

[Child with sitosterolemia initially presenting with hemolytic anemia and thrombocytopenia: a case repore and literrature review]

This article focuses on a case study of sitosterolemia in a child who initially presented with hemolytic anemia and thrombocytopenia. Sitosterolemia is a rare autosomal recessive lipid metabolism disorder, difficult to diagnose due to its non-typical clinical manifestations. The 8-year-old patient was initially misdiagnosed with pyruvate kinase deficiency. Comprehensive biochemical and molecular biology analyses, including gene sequencing, eventually led to the correct diagnosis of sitosterolemia. This case highlights the complexity and diagnostic challenges of sitosterolemia, emphasizing the need for increased awareness and accurate diagnosis in patients presenting with similar symptoms.

Clinical features, imaging findings and molecular data of limb-girdle muscular dystrophies in a cohort of Chinese patients

BACKGROUND

Limb-girdle muscular dystrophies (LGMDs) are a group of heterogeneous inherited diseases predominantly characterized by limb-girdle muscle weakness and dystrophic changes on histological analysis. The frequency of LGMD subtypes varies among regions in China and ethnic populations worldwide. Here, we analyzed the prevalence of LGMD subtypes, their corresponding clinical manifestations, and molecular data in a cohort of LGMD patients in Southeast China.

METHODS

A total of 81 consecutive patients with clinically suspected LGMDs from 62 unrelated families across Southeast China were recruited for targeted next-generation sequencing and whole-exome sequencing from July 2017 to February 2020.

RESULTS

Among 50 patients (41 families) with LGMDs, the most common subtypes were LGMD-R2/LGMD2B (36.6%) and LGMD-R1/LGMD2A (29.3%). Dystroglycanopathies (including LGMD-R9/LGMD2I, LGMD-R11/LGMD2K, LGMD-R14/LGMD2N and LGMD-R20/LGMD2U) were the most common childhood-onset subtypes and were found in 12.2% of the families. A total of 14.6% of the families had the LGMD-R7/LGMD2G subtype, and the mutation c.26_33dupAGGTGTCG in TCAP was the most frequent (83.3%). The only patient with the rare subtype LGMD-R18/LGMD2S had TRAPPC11 mutations; had a later onset than those previously reported, and presented with proximal‒distal muscle weakness, walking aid dependency, fatty liver disease and diabetes at 33 years of age. A total of 22.0% of the patients had cardiac abnormalities, and one patient with LMNA-related muscular dystrophy/LGMD1B experienced sudden cardiac death at 37 years of age. A total of 15.4% of the patients had restrictive respiratory insufficiency. Muscle imaging in patients with LGMD-R1/LGMD2A and LGMD-R2/LGMD2B showed subtle differences, including more severe fatty infiltration of the posterior thigh muscles in those with LGMD-R1/LGMD2A and edema in the lower leg muscles in those with LGMD-R2/LGMD2B.

CONCLUSION

We determined the prevalence of different LGMD subtypes in Southeast China, described the detailed clinical manifestations and distinct muscle MRI patterns of these LGMD subtypes and reported the frequent mutations and the cardiorespiratory involvement frequency in our cohort, all of which might facilitate the differential diagnosis of LGMDs, allowing more timely treatment and guiding future clinical trials.

[Platelet derived growth factor-BB regulates phenotype transformation of pulmonary artery smooth muscle cells via SIRT3 affecting glycolytic pathway]

Objective: To investigate whether platelet-derived growth factor-BB (PDGF-BB) can regulate phenotypic transformation of pulmonary artery smooth muscle cells (PASMCs) via SIRT3 affecting glycolytic pathway. Methods: The PASMCs were isolated from Sprague Dawley rats. PASMCs were divided into 3 groups by using 2-deoxyglucose (2-DG), an inhibitor of the glycolytic pathway: normal control group, PDGF-BB group(30 ng/ml) and PDGF-BB (30 ng/ml)+2-DG (10 mmol/L) group. In lentivirus-mediated overexpression assay, cells were divided into control group, PDGF-BB group(30 ng/ml), PDGF-BB+deacetylase sirtuin-3 (SIRT3) overexpression group and PDGF-BB+empty vector group. The expression levels of phenotype related index such as α-smooth muscle actin (α-SMA), smooth muscle myosin heavy chain (SM-MHC), calponin, vimentin were detected by qRT-PCR and Western blot. Meanwhile, the expression of α-SMA was detected by cellular immunofluorescence staining. EDU staining was used to detect the proliferation of PASMCs. The expression of SIRT3 was detected by Western blot. The expressions of glucose transporter 1 and aerobic glycolytic enzymes were detected by qRT-PCR and Western blot in lentivirus-mediated overexpression assay. Results: (1) PDGF-BB affects PASMCs phenotypic transformation through glycolytic pathway: compared with normal control group, PDGF-BB significantly decreased the expressions of contractile phenotype markers such as α-SMA, SM-MHC, calponin mRNA and protein (all P<0.05), but it increased the expressions of the synthetic phenotype marker vimentin mRNA and protein (both P<0.05). Cellular immunofluorescence assay showed that PDGF-BB significantly decreased the number of α-SMA positive cells, while 2-DG reversed the process. (2) PDGF-BB promoted cell proliferation through glycolytic pathway: the proliferation of PASMCs was significantly higher in PDGF-BB group than in control group (P<0.05), and which could be significantly reduced by 2-DG (P<0.05). (3) PDGF-BB inhibited the expression of SIRT3 protein in PASMCs: the expression of SIRT3 protein in PDGF-BB group was lower than that in control group (P<0.05). (4) PDGF-BB affected glycolytic pathway through SIRT3:compared with the control group, PDGF-BB significantly increased the expression levels of glucose transporter 1 (Glut1), hexokinase 2 (HK2) and 6-phosphfructo-2-kinase 3 (PFKFB3) mRNA (all P<0.05), which was reserved by over-expression of SIRT3. There were no significant difference in mRNA expression levels between PDGF-BB group and PDGF-BB+empty vector group (P>0.05).Compared with the control group, PDGF-BB significantly increased the expression levels of Glut1, HK2 and PFKFB3 protein(all P<0.05), which was reserved by over-expression of SIRT3. There were no significant differences in protein expression levels between PDGF-BB group and PDGF-BB+empty vector group (all P>0.05). Conclusion: PDGF-BB regulates phenotypic transformation of PASMCs via SIRT3 affecting glycolytic pathway.

[Awareness of preconceptional care and its related factors in women of child-bearing age with type 1 diabetes]

Objective: To investigate the awareness of preconception care among women of child-bearing age with type 1 diabetes (T1DM) and their self-management status, in order to provide evidence for establishment of management pathway for women with T1DM in pregnancy in China. Methods: This cross-sectional survey recruited female participants of child-bearing age from the cohort of Guangdong Type 1 Diabetes Translational Medicine Study conducted between June 2011 and December 2017. The participants were asked to fill out a questionnaire on the awareness of preconception care, their frequency of self-monitoring of blood glucose (SMBG) and other related variables. Chi-squared test or chi-squared test for trend was used in comparisons of categorical variables, and logistic regression analysis was performed to assess associated factors. Results: Totally, 441 women of child-bearing age with T1DM were investigated. The results show that their awareness of preconception care was poor (15.42%, 68/441). Higher educational level (χ(2trend)=3.990, P=0.046), experience of post-diabetes education evaluation (P<0.001), and better coverage of different modules in diabetes education (survival skills: χ(2)=7.525, P=0.004; basic knowledge: χ(2)=8.598, P=0.002; advanced knowledge: P<0.001) were associated with better awareness of preconception care. The average frequency of SMBG in these participants was 0.29 (0.14, 2.00) times per day, and only 8.5% (37/435) of them reached the frequency (≥4 times per day) recommended by guidelines. Moreover, 21.1% (92/435) of them hardly ever performed SMBG. Conclusion: Child-bearing age women with T1DM in Gunangdong had poor awareness of preconception care, with a much lower SMBG frequency than recommendation.

[Glycemic control and its associated factors in children and adolescents with type 1 diabetes mellitus]

A higher frequency of SMBG is one of the key factors to achieve sufficient glycemic control among children and adolescents with T1DM treated with CSII.

[Insulin regimes and impact on glycemic control in patients with type 1 diabetes]

Objective: To describe the insulin regimens and their associations with glycemic control and to explore factors associated with intensive insulin therapy. Methods: Patients with type 1 diabetes (T1DM) were recruited from Guangdong Type 1 Diabetes Mellitus Translational Medicine Study which was conducted in 16 centers in Guangdong province. The demographic and clinical data were collected. Patients were grouped according to different insulin regimens: insulin pump (R1), basal insulin plus regular insulin or short-acting insulin (R2), insulin injection 1-3 times per day (R3). Distribution of insulin regimens and the relationships between insulin regimens and hemoglobin A1c (HbA1c) were described. Multivariate logistic regression was used to identify factors associated with intensive insulin therapy. Results: A total of 1 421 patients with the age of 27.8 (19.4, 38.3) years and a duration of T1DM of 3.3 (0.5, 7.1) years were recruited. There was 12.3% of patients in R1 (n=175), 35.5% in R2 (n=504), and 52.2% in R3 (n=742), respectively. HbA1c was 8.0 (6.8, 9.3)%, 8.9 (7.1, 11.8)%, and 9.2 (7.5, 11.4)% in R1, R2, R3, respectively, and it was associated with insulin regimens (P<0.001). HbA1c target rate was 32.3%, 21.1%, 17.8% in R1, R2, R3, respectively (P=0.002). Older age (OR=1.01, P=0.027), higher education level (college or above) (OR=1.56, P=0.003), and higher household income (>30 000 yuan per year per person)(OR=1.45, P=0.009) were associated with intensive insulin therapy in adult patients. Conclusions: The study suggested that insulin therapy need to be optimized in patients with T1DM. The optimization of insulin regimens and diabetes education may be helpful for improvement of glycemic control.

Comparative RNA profile analysis of idiopathic dilated cardiomyopathy and ischemic cardiomyopathy

Previous research has focused on revealing the functions of each individual gene and/or pathway in idiopathic dilated cardiomyopathy (DCM) or ischemic cardiomyopathy (IC). However, the common or specific pathways of the initiation and processes of DCM and IC are still unclear. Here, we attempted to uncover the critical genes and potential molecular networks that play important roles in DCM and IC progression commonly or specifically. The transcriptional profiles from normal and DCM or IC patient samples were analyzed and compared using bioinformatic methods. Initially, the normal and DCM or IC sample data were processed and the most notable differentially expressed genes (DEGs) from DCM or IC were identified. By comparing the DEGs from DCM with those from IC, the DCM- and IC-specific DEGs were identified. The gene ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses indicated the significance of multiple biological processes as well as signaling pathways that affect heart function and DCM or IC progression. Protein-protein interaction network analysis identified the relationships between different genes, and some important genes such as MYC and FN1 were found to be hubs, which master each individual module of DCM-specific and IC-specific DEGs, respectively. We discovered commonalities and differences of gene expression profiles and molecular pathways between different cardiomyopathies. The gene discovery and molecular signature analysis in this study could offer insights into disease mechanisms and also identify markers useful for diagnostic, prognostic, and therapeutic purposes.

Neurobehavioural abnormalities induced by repeated exposure of neonatal rats to sevoflurane can be aggravated by social isolation and enrichment deprivation initiated after exposure to the anaesthetic

BACKGROUND

We tested the hypothesis that developmental effects of repeated neonatal exposure to sevoflurane in rats are exacerbated by stressful experiences received later in life.

METHODS

Sprague-Dawley male rats received sequential exposures to 3% sevoflurane for two h on postnatal days (P) six, seven, and eight. After weaning at P21, rats were housed either in pairs in an enriched environment (EE) or singly in an enrichment-deprived environment (an adverse environment, AE). The hippocampal concentrations of brain-derived neurotrophic factor (BDNF), and synaptic markers were assessed at P8 and P53. The dentate gyrus neural progenitor proliferation was evaluated at P11 and P53 after administration of bromodeoyuridine (BrdU) at P8 to P10 and at P22 to P27, respectively. Neurobehavioural evaluations were performed at P49 to P53.

RESULTS

Repeated sevoflurane exposure acutely reduced concentrations of BDNF, synaptic markers and neural progenitor proliferation. The sevoflurane group housed in the AE conditions (sevoflurane+AE) had decreased concentrations of BDNF and synaptic markers, and survival of new granule cells and impaired cognitive function compared with the control+AE, control+EE, and sevoflurane+EE groups. The neurobehavioural parameters in the sevoflurane+EE and control+EE groups were similar.

CONCLUSIONS

Neurocognitive abnormalities induced by repeated neonatal exposure to sevoflurane can be aggravated by stressful conditions such as social isolation and enrichment deprivation.

Characterization of novel nitrate reductase-deficient mutants for transgenic Dunaliella salina systems

The aim of the present study was to isolate and characterize novel nitrate reductase (NR)-deficient mutants, which may be useful for the transgenic manipulation of Dunaliella salina. Three NR-deficient mutants of D. salina, J-1, J-2, and J-3, were successfully isolated by screening for chlorate resistance after chemical mutagenesis with ethylnitrosourea. NR activity was not detected in the mutants and the expression of NR mRNA was significantly decreased. Growth analysis of D. salina strains grown in media containing different nitrogen sources revealed that these mutants were capable of utilizing nitrite and urea, but not nitrate as a nitrogen source, indicating that these mutants are indeed NR-deficient. Mutation analysis of NR cDNA sequences revealed that there were 11 point mutations shared by the J-1, J-2, and J-3 mutants. Furthermore, the results of the functional complementation experiment showed that NR activity of transformant T-1 derived from J-1 was recovered to 48.1 % of that of the wild-type D. salina. The findings of the present study indicate that nitrate may be used as a selective agent rather than antibiotics or herbicides for the isolated NR-deficient mutants in future transgenic D. salina systems.

A novel amber mutation in a beta zero-thalassaemia gene (beta 37TGG-->TAG), with direct detection by mapping the restriction fragments in amplified genomic DNA

A novel amber mutation, a G to A substitution at the second position of codon 37 in the beta-globin gene that changes the tryptophan coding triplet (TGG) to a termination codon (TAG), was found in a Chinese beta-thalassaemia carrier. The mutant gene creates an additional Dde I recognition site and eliminates the Ava II site, so this point mutation can be directly identified by restriction enzyme analysis.

Microvascular decompression for trigeminal neuralgia

Of 42 patients undergoing a microvascular decompression for trigeminal neuralgia with a follow-up of 4 to 7 years, 32 (76.19%) had no postoperative recurrence of neuralgic pain, 4 (9.52%) had a minor recurrence and 6 (14.29%) had a major recurrence. It was considered that the neuralgic recurrence might be due to some possibly missed pathogenic vessel during operation or a new compression of the trigeminal nerve root occurring after operation.