Aberrant intra- and internetwork functional connectivity patterns of the anterior and posterior hippocampal networks in schizophrenia.

AIM: Schizophrenia is associated with abnormal hippocampal structure and function. Available evidence suggests that the anterior and posterior hippocampus are differentially affected by schizophrenia pathology. This study was designed to provide new insight into the anterior and posterior hippocampus in schizophrenia from the perspective of functional connectivity. METHODS: Based on resting-state functional magnetic resonance imaging data of 71 schizophrenia patients and 74 normal controls, we utilized a data-driven approach to functionally segment the hippocampus into anterior and posterior segments and then investigated the functional connectivity patterns within and between the two hippocampal networks at the network, edge, and nodal levels. RESULTS: We found that schizophrenia patients showed hyperconnectivity of both the anterior and posterior hippocampal networks. We also observed that the network alterations appear somewhat greater in the anterior hippocampal network than the posterior network, the left side than the right, and the intranetwork connectivity than the internetwork connectivity. CONCLUSION: The results reveal convergent and divergent intranetwork and internetwork connectivity patterns of the anterior and posterior hippocampus in schizophrenia, providing novel and important insights into the mechanisms of hippocampal pathology in schizophrenia.

Brain morphometric abnormalities in boys with attention-deficit/hyperactivity disorder revealed by sulcal pits-based analyses.

AIM: Attention-deficit/hyperactivity disorder (ADHD) is a common neurodevelopmental disorder associated with widespread brain morphological abnormalities. Here, we utilized a sulcal pits-based method to provide new insight into the atypical cortical folding morphology in ADHD. METHODS: Sulcal pits, the locally deepest points in each fold, were first extracted from magnetic resonance imaging data of 183 boys with ADHD (10.62 ± 1.96 years) and 167 age- and gender-matched typically developing controls (10.70 ± 1.73 years). Then, the geometrical properties of sulcal pits were statistically compared between ADHD and controls. RESULTS: Our results demonstrated that the number of sulcal pits was reduced and confined to the superficial secondary sulci in the ADHD group relative to controls (P < .05). We also found that ADHD boys were associated with significantly increased pit depth in the left superior frontal junction, circular insular sulcus, right inferior frontal junction, and bilateral cingulate sulcus, as well as significantly decreased pit depth in the bilateral orbital sulcus (P < .05, corrected). CONCLUSION: The experimental findings reveal atypical sulcal anatomy in boys with ADHD and support the feasibility of sulcal pits as anatomic landmarks for disease diagnosis.

[Liquid gastric-emptying measurement using an electrical bio-impedance method].

This paper introduces a 4-electrode gastric-emptying measurement system using an electrical bio-impedance method by which gastric-emptying experiments of 24 healthy volunteers have been carried out. The test results show that the base impedance is stable, the average GET/2 is 8.78 +/- 1.76 min. The new system provides a new non-invasive measurement method for the clinical study on gastric-emptying functions.

[The relationship between resting heart rate and single nucleotide polymorphism at 3 sites of nitric oxide synthase gene in the Chinese Han nationality population].

OBJECTIVE: To study the relationship between resting heart rate and single nucleotide polymorphisms (SNP) at 3 sites of nitric oxide synthase (NOS) gene including NOS3 -922A/G, NOS3 894G/T and NOS2 -1173C/T SNPs. METHODS: Genomic DNA was gained from 211 Chinese Han nationality population. The SNPs of NOS3 -922A/G, NOS3 894G/T and NOS2 -1173C/T were genotyped by allele-specific primer-polymerase chain reaction (ASP-PCR) technique. RESULTS: The distribution frequencies of GG, GT and TT genotypes of NOS3 894G/T and AA, AG and GG genotypes of NOS3 -922A/G and CC, CT and TT genotypes of NOS2 -1173C/T were consistent with Hardy-Weinberg equilibrium (P> 0.05). The resting heart rate of Chinese Han nationality population with AA genotypes was higher than that with GG genotype of NOS3 -922A/G (P< 0.01). The resting heart rate of the sub-population with GG genotype was higher than that with TT genotype of NOS3 894G/T (P< 0.05). There were no difference among the resting heart rates of the sub-populations with the allele genotypes of NOS2 -1173C/T. CONCLUSION: The resting heart rate of Chinese Han nationality population with mutated genotype GG of NOS3 -922A/G and with mutated genotype TT of NOS3 894G/T were lower than those with wild genotype of NOS3 -922A/G and NOS3 894G/T. The finding suggests that resting heart rate is associated with SNP of NOS3 -922A/G and NOS3 894G/T.

[Single nucleotide polymorphisms in NOS3 A-922G, T-786C and G894T: a correlation study of the distribution of their allelic combinations with hypertension in chinese Han population].

To study single nucleotide polymorphisms (SNP) in A-922G, T-786C and G894T of endothelial nitric oxide synthase (NOS3) and to correlate the distribution of their allelic combinations with hypertension in Chinese Han nationality population, genomic DNA was isolated from venous blood leukocytes from 192 unrelated patients with hypertension (95 females and 97 males) and 122 healthy unrelated individuals (46 females and 76 males) as controls. SNPs of NOS3 A-922G, T-786C and G894T were genotyped by allele-specific primer (ASP) PCR. The distribution of genotype combinations of three SNPs was determined by clustering analysis. There were no difference in allele genotype distribution frequency and haplotype frequency of NOS3 G894T, NOS3 A-922G and NOS3 T-786C between the essential hypertension group and the healthy population (P>0.05). According to sex stratification, no association between essential hypertension and SNP of NOS3 A-922G,NOS3 T-786C or NOS3 G894T has been found in either the male subgroup or the female subgroup. In respect of allele genotype combination frequency in the natural distribution of NOS3 A-922 G, NOS3 T-786C and NOS3 G894T SNP, there was significant difference only in the allele genotype combination frequency of NOS3 G894G+A-922G+T-786T between the hypertension group and the healthy group (P<0.05, Chi2=4.5944). According to sex stratification, there were no significant difference in all above allele genotype combination frequency in three sites of NOS3 SNP between the hypertension male subgroup and the healthy male subgroup (P>0.05). There was significant difference in the allele combination frequency of NOS3 G894G +A-922G+T-786C between the hypertension female subgroup and the healthy female subgroup(P<001, Chi2=8.502). There was no association of SNP in NOS3 A-922G, NOS3 T-786C or NOS3 G894T with hypertension in the Chinese Han nationality population, nor was there a sex difference. The combination frequency of allele NOS3 G894G + A-922G + T-786C in the hypertension female subgroup was much lower than that in the healthy female subgroup, suggesting that female population with this combination genotype may be less susceptible to hypertension.

[Extraction of rabbit somatosensory evoked potentials (SEP) with independent component analysis].

OBJECTIVE: To extract rabbit somatosensory evoked potentials (SEP), by using a new technique named independent component analysis. METHOD: The rabbit was narcotized and stimulated with 0.5 Hz electric pulse. Potentials at scalp was sampled at 3764 Hz. Response signals to repeated stimulations for 3 times mixed with background noise was acquired at the same collection point. Independent component analysis (ICA) for SEP was established. The mixed signals were decomposed by ICA to observe the independent components. RESULT: Independent SEP was acquired. CONCLUSION: A time lag of continuous signal source is suitable to SEP model. ICA can extract signals of SEP components.

Electrical bioimpedance gastric motility measurement based on an electrical-mechanical composite mechanism.

AIM: To introduce a bioimpedance gastric motility measurement method based on an electrical-mechanical composite concept and a preliminary clinical application. METHODS: A noninvasive gastric motility measurement method combining electrogastrogram (EGG) and impedance gastric motility (IGM) test was used. Preliminary clinical application studies of patients with functional dyspepsia (FD) and gastritis, as well as healthy controls, were carried out. Twenty-eight FD patients (mean age 40.9 ± 9.7 years) and 40 healthy volunteers (mean age 30.9 ± 7.9 years) were involved. IGM spectrum was measured for both the healthy subjects and FD patients, and outcomes were compared in the FD patients before treatment and 1 wk and 3 wk after treatment. IGM parameters were obtained from 30 erosive gastritis patients (mean age 50.5 ± 13.0 years) and 40 healthy adults, and IGM and EGG results were compared in the gastritis patients before treatment and 1 wk after treatment. RESULTS: There were significant differences in the IGM parameters between the FD patients and healthy subjects, and FD patients had a poorer gastric motility [percentage of normal frequency (PNF) 70.8 ± 25.5 in healthy subjects and 28.3 ± 16.9 in FD patients, P < 0.01]. After 1 wk administration of domperidone 10 mg, tid, the gastric motility of FD patients was not improved, although the EGG of the patients had returned to normal. After 3 wk of treatment, the IGM rhythm of the FD patients became normal. There was a significant difference in IGM parameters between the two groups (PNF 70.4 ± 25.5 for healthy subjects and 36.1 ± 21.8 for gastritis patients, P < 0.05). The EGG rhythm of the gastritis patients returned to normal (frequency instability coefficient 2.22 ± 0.43 before treatment and 1.77 ± 0.19 one wk after treatment, P < 0.05) after 1 wk of treatment with sodium rabeprazole tablets, 10 mg, qd, po, qm, while some IGM parameters showed a tendency toward improvement but had not reached statistical significance. CONCLUSION: The electrical-mechanical composite measurement method showed an attractive clinical application prospect in gastric motility research and evaluation.

Gastric motility functional study based on electrical bioimpedance measurements and simultaneous electrogastrography.

For some time now, the research on gastric motility and function has fallen behind in the amount of research on gastric endocrine, exocrine secretion, and gastric morphology. In this paper, a noninvasive method to study gastric motility was developed, taking bioimpedance measurements over the gastric area simultaneously with the electrogastrography (EGG). This is based on the concept of observing and analyzing simultaneously the intrinsic electrical gastric activity (basic electric rhythm) and the mechanical gastric activity. Additionally, preliminary clinical studies of healthy subjects and subjects with functional dyspepsia (FD) and gastritis were carried out. The impedance gastric motility (IGM) measurements of the healthy and FD subjects were compared, along with the studies of the FD subjects before treatment and after one week and three weeks of treatment. We also compared IGM measurements of healthy subjects and subjects with erosive gastritis, along with the studies of the subjects with erosive gastritis before treatment and after one week of treatment. Results show that FD subjects have poor gastric motility (P<0.01). After a week of treatment, the gastric motility of FD subjects was not yet improved although the EGG had returned to normal by this time. By three weeks of treatment, the regular IGM rhythm returned in FD subjects. There was a significant difference of IGM parameters between the gastritis and healthy subjects (P<0.05). The EGG rhythm of the gastritis subjects returned to normal at one week post-treatment, while IGM parameters showed a trend to improvement (P>0.05), These results suggest the possibility of clinic application of the proposed method.