A machine learning model using gut microbiome data for predicting changes of trimethylamine-N-oxide in healthy volunteers after choline consumption / 南方医科大学学报

<p><b>OBJECTIVE</b>To establish a machine learning model based on gut microbiota for predicting the level of trimethylamine N-oxide (TMAO) metabolism in vivo after choline intake to provide guidance of individualized precision diet and evidence for screening population at high risks of cardiovascular disease.</p><p><b>METHODS</b>We quantified plasma levels of TMAO in 18 healthy volunteers before and 8 h after a choline challenge (ingestion of two boiled eggs). The volunteers were divided into two groups with increased or decreased TMAO level following choline challenge. Fresh fecal samples were collected before taking fasting blood samples for amplifying 16S rRNA V4 tags, and the PCR products were sequenced using the platform of Illumina HiSeq 2000. The differences in gut microbiata between subjects with increased and decreased plasma TMAO were analyzed using QIIME. Based on the gut microbiota data and TMAO levels in the two groups, the prediction model was established using the machine learning random forest algorithm, and the validity of the model was tested using a verified dataset.</p><p><b>RESULTS</b>An obvious difference was found in beta diversity of the gut microbota between the subjects with increased and decreased plasma TMAO level following choline challenge. The area under the curve (AUC) of the model was 86.39% (95% CI: 72.7%-100%). Using the verified dataset, the model showed a much higher probability for correctly predicting TMAO variation following choline challenge.</p><p><b>CONCLUSION</b>The model is feasible and reliable for predicting the level of TMAO metabolism in vivo based on gut microbiota.</p>

Longitudinal analysis of vaginal microbiota in women with recurrent vulvovaginal candidiasis / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the vaginal flora in patients with recurrent vulvovaginal candidiasis (RVVC).</p><p><b>METHODS</b>Vaginal swabs were collected at different time points from 6 RVVC patients and 5 healthy women of child-bearing age. The dynamic changes, microbiota composition, alpha diversity and beta diversity in the two groups were assessed by analyzing the 16S rRNA V4 hypervariable region amplified from the total genomic DNA from the swabs.</p><p><b>RESULTS</b>Lactobacillus was the predominant species in healthy women with similar proportions of L.iners and L.crispatus; small proportions of Gardnerella, Prevotella and other genus were also detected. In some healthy women, the vaginal flora showed a high relative abundance of anaerobic bacteria such as Gardnerella, Prevotella, Atopobium, Sneathia. Compared with the healthy women, patients with RVVC showed a significantly reduced diversity of vaginal flora, where L.iners was the predominant species and the content of L.crispatus decreased significantly. In healthy women, the vaginal flora fluctuated with the menstrual cycle, and the fluctuation was the most prominent during menstruation; the dominant species either alternated regularly or maintain an absolute superiority in the menstrual cycle. The vaginal flora showed attenuated fluctuation in women with RVVC, were highly conserved within the menstrual cycle, and maintained a similar composition in the episodes and intermittent periods.</p><p><b>CONCLUSION</b>The vaginal flora of RVVC patients do not undergo regular variations with the menstrual cycle and shows a similar composition between the episodes and intermittent periods. Promoting the production of L.iners or inhibiting the colonization of L.crispatus to restore the composition of the vaginal flora may help in the treatment of RVVC.</p>

Spatial characteristic of distribution of Oncomelania hupensis in mountainous regions / 中华流行病学杂志

Objective To analyze the spatial characteristic on the distribution of Oncomelania hupensis in mountainous regions.Methods Based on the geographic database of snail distribution in Puge county,Sichuan province,spatial autocorrelation analysis and spatial scan statistics were applied to analyze the spatial characteristic of snail distribution.Results With regard to the rate of frame with snails,the global Moran's I indicator was 0.095(P<0.05),which indicated the spatial autocorrelation of snail distribution in Puge county.Data from the local spalial autocorrelation analysis showed that there were 28 snail habitats with statistically significant differences on local indicators of spatial autocorrelation(LISA)value(P<0.05),among which existed high-high,low-low,low-high and high-low four types of correlation model.The Spatial Scan Statistics had in total identified 24 snail habitat clusters(P<0.05),including 14 high rate clusters and 10 low rate clusters,and the result was similar to that of LISA analysis.Conclusion There were spatial autocorrelation and spatial aggregation of snail distribution in mountainous regions,meanwhile spatial heterogeneity of snail distribution also existed.This law could be explored for beaer control of snails.

Screening for simulation peptide specifically binding to the first and the second extra-cellular domain of CCR5 and its therapeutic effect on mice with autoimmune encephalomyelitis / 第二军医大学学报

Objective: To screen for simulation peptide binding specifically to the first and the second extra-cellular domain of CC chemokine receptor 5 (CCR5), and to observe their therapeutic effect on mice with experimental autoimmune encephalomyelitis (EAE). Methods: Phage display peptide library was used to screen for peptide sequence binding specifically to CCR5; ELISA was used to identify its binding activity and analyze its DNA sequence. The simulation peptide was synthesized and was injected into abdominal cavity of the EAE mice. Spinal cord tissues were obtained and the pathologic changes were studied by H-E staining in EAE control group and simulation peptide group. Results: Twenty phage clones were randomly chosen for identification and ELISA showed that there were eighteen clones had a strong binding activity with CCR5. The positive clones were sequenced and four peptides of high frequency were obtained: STFTTTL, TPIPQLL, SLPLPKP, and QTSSAAL. Mean clinical score of mice in the EAE model group was 3 and that of the simulation peptide group was 1. H-E staining found that the spinal cord tissues in EAE model group had great number of inflammatory cells and evident demyelination changes; the simulation peptide group had less inflammatory cells and no demyelination changes. The four short peptides had an effect of suppressing and delaying the development of EAE, with the average inhibition rate being 43% (P<0.05). Conclusion: The screened CCR5 simulation peptide has evident inhibitory effect against EAE, indicating that CCR5 may play an important role in the course of multiple sclerosis (MS).

Clinical and genetic study of spinocerebellar ataxia type 7 in East Asian population / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Spinocerebellar ataxia type 7 (SCA7) is known as an autosomal dominant cerebellar ataxia; patients with genetically confirmed diagnoses of SCA7 have increased rapidly in recent years. However, SCA7 is a rare subtype of SCA, and most data available about SCA7 are those of white people. The aim of the present study was to systematically review the prevalence and clinical and genetic aspects of SCA7 patients in East Asian population.</p><p><b>METHODS</b>A search for publications on SCA7 was performed by using the "PubMed" database with the published language limited in English. Publications mainly focusing on the prevalence of SCA7 in patients with SCA and the clinical and genetic features of SCA7 patients were fully reviewed and analyzed.</p><p><b>RESULTS</b>The prevalence of SCA7 in SCA patients ranged from 0 to 7.7%, which was similar to those reported previously. The clinical manifestations were typically present at the 30's of its victims (median, 29 years; interquartile range (IQR), 19.5-36.5 years), and the symptoms appeared 15 years ((15.17+/-4.22) years) earlier on average in the offspring than in the parents. Gait ataxia and visual impairment were both found in all patients of whom the clinical features were described. Mutant SCA7 alleles contained 40-100 CAG repeats, with a median of 47 repeats (IQR, 44.5-50.0); and the offspring had 13 more repeats on average compared with their parents (12.62+/-19.03). A strong negative correlation was found between CAG repeat size and the onset age of patients (r=-0.739, P=0.000). In addition, no significant difference was found in CAG repeat sizes between patients with visual impairment as the initial symptom and those with gait disturbance as their initial symptom (P=0.476).</p><p><b>CONCLUSIONS</b>The prevalence of SCA7 in SCA patients, the age at onset and CAG repeats of SCA7 patients in East Asia are consistent with those of white people. However, larger population study is needed to assess the correlation between the CAG repeat size and initial symptoms of SCA7 patients in East Asia.</p>

Acute subdural hematoma with swirl signs: clinical analysis of 15 cases / 中华创伤杂志(英文版)

From July 2003 to July 2009, 15 cases of subdural hematoma with swirl signs were treated in our hospital and their clinical data were retrospectively analysed. The mortality was compared between these patients and those with typical acute subdural hematoma who were treated at the same time in our hospital. Among the 15 cases, full recovery was achieved in 4 cases, slight disability in 2, grave disability in 2 and death in 7 (46.7%). The mortality of these patients was conspicuously higher than that of typical subdural hematoma (14/83, 16.9%, P < 0.01). Subdural hematoma with swirl signs is often suggestive of hazardous pathogenetic condition and early diagnosis and prompt surgical intervention is essential to reduce mortality.

The alpha-synuclein gene microsatellite polymorphism and late-onset sporadic Parkinson's disease susceptibility / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To explore the association of the microsatellite polymorphisms in the promoter region of alpha-synuclein gene with the late-onset sporadic Parkinson's disease (PD) susceptibility.</p><p><b>METHODS</b>The microsatellite polymorphism of alpha-synuclein gene was analyzed with amplified fragment length polymorphism (Amp-FLP) and semiautomatic fluorescent labeled genotyping technique. Association analysis was performed in 135 unrelated late-onset sporadic PD patients and 170 age-matched healthy controls.</p><p><b>RESULTS</b>The distribution of the alleles of the dinucleotide repeats variants of alpha-synuclein gene promoter region in PD cases was significantly different from that in the healthy controls. The most frequent allele in PD patients was allele 269 bp, but in controls it was the 271 bp allele. Alleles of <or=267 bp showed positive correlation with PD risk (OR=5.228, 95%CI: 1.248-27.202, chi-square=6.416, P=0.011), while the 273 bp allele was negatively correlated to PD (OR=0.638, 95%CI: 0.440-0.926, chi-square=5.644, P=0.018). Furthermore, no difference of genotype polymorphism distribution was shown between the two groups (chi-square=16.368, df=12, P=0.175). But the genotypes containing <or=267 bp allele may increase the susceptibility to PD (OR=4.594, 95%CI: 0.94-22.49, chi-square=4.224, P=0.04). Heterozygosity was 40% in PD patients, and 50% in controls.</p><p><b>CONCLUSION</b>alpha-synuclein microsatellite polymorphism might be a genetic susceptibility factor for late-onset sporadic PD.</p>

Clinical and gene study on one pedigree of hereditary spinocerebellar ataxia type 7 / 中华神经科杂志

Objective To summarize the clinical characteristics and make genetic diagnosis in the patients with hereditary spinocerebellar ataxia type 7 (SCA7).Methods Pedigree analysis and clinical examination were performed in one family with SCA7 by clinical findings,of which retinal morphology and visual electrophysiology were available on part numbers.The polymorphic cytosine adenine guanine (CAG) repeats in the encode region of SCA7 gene were detected by combining polymerase chain reaction with deoxyribonucleic acide (DNA) sequencing on 19 familial numbers and 12 controls.Results 6 patients were identified,who manifesting cerebellar ataxia,decreased visual acuity and colour vision defect,as was pigmentary retinopathy on fundoscopy;The 6 patients had not only extinction of the electroretinogram (ERG) but also remarkably reduced amplitudes of oscillatory potentials and flash-visual evoked potentials. On normal alleles CAG repeat size ranges from 8 to 25 repeats,wherease on mutated alleles of the 6 numbers it ranges from 50 to 97 repeats.The 6 numbers were diagnosised as SCA7 patients.One asymptomatic individual of this family,who displayed a normal allele with 18 CAG repeats and another containing abnormal expantion of 56 repeats,was diagnosised as a asymptomatic carrier whose age maybe still below the age of onset.Conclusion The clinical manifestations of SCA7 are heterogeneous,and the detection of CAG repeats can provide an effective way for the gene diagnosis and the prediction of asymptomatic patients.