Highly Sensitive Detection of Hydrogen Peroxide in Cancer Tissue Based on 3D Reduced Graphene Oxide-MXene-Multi-Walled Carbon Nanotubes Electrode.

Hydrogen peroxide (H2O2) is a signaling molecule that has the capacity to control a variety of biological processes in organisms. Cancer cells release more H2O2 during abnormal tumor growth. There has been a considerable amount of interest in utilizing H2O2 as a biomarker for the diagnosis of cancer tissue. In this study, an electrochemical sensor for H2O2 was constructed based on 3D reduced graphene oxide (rGO), MXene (Ti3C2), and multi-walled carbon nanotubes (MWCNTs) composite. Three-dimensional (3D) rGO-Ti3C2-MWCNTs sensor showed good linearity for H2O2 in the ranges of 1-60 µM and 60 µM-9.77 mM at a working potential of -0.25 V, with sensitivities of 235.2 µA mM-1 cm-2 and 103.8 µA mM-1 cm-2, respectively, and a detection limit of 0.3 µM (S/N = 3). The sensor exhibited long-term stability, good repeatability, and outstanding immunity to interference. In addition, the modified electrode was employed to detect real-time H2O2 release from cancer cells and cancer tissue ex vivo.

The Simultaneous Detection of Dopamine and Uric Acid In Vivo Based on a 3D Reduced Graphene Oxide-MXene Composite Electrode.

Dopamine (DA) and uric acid (UA) are essential for many physiological processes in the human body. Abnormal levels of DA and UA can lead to multiple diseases, such as Parkinson's disease and gout. In this work, a three-dimensional reduced graphene oxide-MXene (3D rGO-Ti3C2) composite electrode was prepared using a simple one-step hydrothermal reduction process, which could separate the oxidation potentials of DA and UA, enabling the simultaneous detection of DA and UA. The 3D rGO-Ti3C2 electrode exhibited excellent electrocatalytic activity towards both DA and UA. In 0.01 M PBS solution, the linear range of DA was 0.5-500 µM with a sensitivity of 0.74 µA·µM-1·cm-2 and a detection limit of 0.056 µM (S/N = 3), while the linear range of UA was 0.5-60 µM and 80-450 µM, with sensitivity of 2.96 and 0.81 µA·µM-1·cm-2, respectively, and a detection limit of 0.086 µM (S/N = 3). In 10% fetal bovine serum (FBS) solution, the linear range of DA was 0.5-500 µM with a sensitivity of 0.41 µA·µM-1·cm-2 and a detection limit of 0.091 µM (S/N = 3). The linear range of UA was 2-500 µM with a sensitivity of 0.11 µA·µM-1·cm-2 and a detection limit of 0.6 µM (S/N = 3). The modified electrode exhibited advantages such as high sensitivity, a strong anti-interference capability, and good repeatability. Furthermore, the modified electrode was successfully used for DA measurement in vivo. This could present a simple reliable route for neurotransmitter detection in neuroscience.

Amphioxus Gli knockout disrupts the development of left-right asymmetry but has limited impact on neural patterning.

The Gli transcription factors are the primary mediators of Hedgehog (Hh) signaling. Vertebrate genomes contain multiple Gli paralogues with different functions downstream of Hh signal receipt, in part explaining the complexity of cellular responses to Hh that allow concentration-dependent target gene activation. Amphioxus is a chordate that split from the vertebrate lineage early in the evolution of chordates, before the genome duplications that occurred in early vertebrate evolution. It has a single Gli gene whose transcripts can be alternately spliced to yield two protein isoforms called GliS and GliL. We generated two knockout mutations in amphioxus Gli, one that affects the whole gene and a second that only affects GliL. Both knockouts showed major morphological and molecular defects in the development of left-right asymmetry, a phenotype that is similar but not identical to that previously found in Hh mutants. Hh signaling also patterns the amphioxus neural tube. Here, however, knockout of GliL showed no identifiable phenotype, while knockout of the full gene showed only small changes to the expression of one gene family, Olig. Other genes that were prominently affected by Hh knockout were not altered in expression in either knockout. Reasons for the differences between Hh and Gli knockouts in the pharynx and neural tube are discussed in the context of the likely different functions of amphioxus Gli isoforms. Supplementary Information: The online version contains supplementary material available at 10.1007/s42995-023-00195-w.

Classification of Schizophrenia by Combination of Brain Effective and Functional Connectivity.

At present, lots of studies have tried to apply machine learning to different electroencephalography (EEG) measures for diagnosing schizophrenia (SZ) patients. However, most EEG measures previously used are either a univariate measure or a single type of brain connectivity, which may not fully capture the abnormal brain changes of SZ patients. In this paper, event-related potentials were collected from 45 SZ patients and 30 healthy controls (HCs) during a learning task, and then a combination of partial directed coherence (PDC) effective and phase lag index (PLI) functional connectivity were used as features to train a support vector machine classifier with leave-one-out cross-validation for classification of SZ from HCs. Our results indicated that an excellent classification performance (accuracy = 95.16%, specificity = 94.44%, and sensitivity = 96.15%) was obtained when the combination of functional and effective connectivity features was used, and the corresponding optimal feature number was 15, which included 12 PDC and three PLI connectivity features. The selected effective connectivity features were mainly located between the frontal/temporal/central and visual/parietal lobes, and the selected functional connectivity features were mainly located between the frontal/temporal and visual cortexes of the right hemisphere. In addition, most of the selected effective connectivity abnormally enhanced in SZ patients compared with HCs, whereas all the selected functional connectivity features decreased in SZ patients. The above results showed that our proposed method has great potential to become a tool for the auxiliary diagnosis of SZ.

Step-wise evolution of neural patterning by Hedgehog signalling in chordates.

In vertebrate embryos, Hedgehog (Hh) is expressed in some anterior basal plate domains and by notochord and floorplate cells, and ventral neural cells are patterned by the activities of Hh-regulated transcription factors. Hh signalling is antagonized by signals from the dorsal neural tube and loss of Hh leads to loss of ventral patterning as dorsal pattern expands. These mechanisms are critical for producing the neurons that implement motor responses to sensory inputs but understanding how they evolved has been hindered by lack of insight from commonly studied invertebrates where nervous system morphology and genetic mechanisms are non-conserved with vertebrates. The invertebrate chordate amphioxus, which expresses Hh in its notochord and floorplate, provides a window into the prevertebrate condition. We examined amphioxus neural development by manipulating Hh and downstream genes involved in neural pattern and cell identity. We show that Hh signalling regulates the differentiation of some neurons in amphioxus, including a subset of motor neurons. This demonstrates some conservation of mechanism between vertebrates and amphioxus. However, other aspects of neural patterning differ between the lineages. We suggest the complexity of Hh-dependent neural patterning in vertebrates evolved in a step-wise manner. Alongside other previously described regulatory changes, initial recruitment of Hh along the length of the axis occurred in an ancestor to the chordates to regulate the differentiation of a subset of neurons. This was followed, in the vertebrate lineage, by additional changes to the downstream gene regulatory network of transcription factors, giving Hh a broader role in dorsal-ventral neural patterning.

Dynamic changes of brain networks during feedback-related processing of reinforcement learning in schizophrenia.

Previous studies have reported that schizophrenia (SZ) patients showed selective reinforcement learning deficits and abnormal feedback-related event-related potential (ERP) components. However, how the brain networks and their topological properties evolve over time during transient feedback-related cognition processing in SZ patients has not been investigated so far. In this paper, using publicly available feedback-related ERP data which were recorded from SZ patients and healthy controls (HC) when they performed a reinforcement learning task, we carried out an event-related network analysis where topology of brain functional networks was characterized with some graph measures including clustering coefficient (C), global efficiency (Eglobal) and local efficiency (Elocal) on a millisecond timescale. Our results showed that the brain functional networks displayed rapid rearrangements of topological properties during transient feedback-related cognition process for both two groups. More importantly, we found that SZ patients exhibited significantly reduced theta-band (time window of 170-350 ms after stimuli onset) brain functional connectivity strength, Eglobal, Elocal and C in response to negative feedback stimuli compared to HC group. The network based statistic (NBS) analysis detected one significantly decreased theta-band subnetwork in SZ patients mainly involving in frontal-occipital and temporal-occipital connections compared to HC group. In addition, clozapine treatment seemed to greatly reduce theta-band power and topological measures of brain networks in SZ patients. Finally, the theta-band power, graph measures and functional connectivity were extracted to train a support vector machine classifier for classification of HC from SZ, or Cloz + SZ or Cloz- SZ, and a relatively good classification accuracy of 84.48%, 89.47% and 78.26% was obtained, respectively. The above results suggested a less optimal organization of theta-band brain network in SZ patients, and studying the topological parameters of brain networks evolve over time during transient feedback-related processing could be useful for understanding the pathophysiologic mechanisms underlying reinforcement learning deficits in SZ patients.

The resilience status of Chinese left-behind children in rural areas: a meta-analysis.

The resilience has become the main trend of the left-behind children's (LBC) mental health research. To evaluate the resilience status of Chinese LBC in rural areas, a meta-analysis was performed. Relevant studies were identified using electronic databases from 1990 to 2017. Pooled weighted mean difference (WMD) and 95% confidence interval (95% CI) were calculated with fixed and random effects models. A total of 14 cross-sectional studies with 9777 individuals were included in this meta-analysis. The results showed there was significant difference in the aspects of family support and RSCA (Resilience Scale for Chinese Adolescents) total score between LBC and non-left-behind children (NLBC). After stratification subgroup, significant difference in RSCA total score was also found in subgroup with sample size ≥700 and target population (LBC) between LBC and NLBC. In addition, there was no significant difference in resilience of male and female among LBC (P >0.05). We also found RSCA total score of LBC whose one parents migratingwere higher than both parents (P <0.05) and the time of parental migration (≤2 years) were higher than others (>2 years). In conclusion, more attention should be paid to the LBC, especially both parents migrating or parental migration (>2 years).

Dense U-net Based on Patch-Based Learning for Retinal Vessel Segmentation.

Various retinal vessel segmentation methods based on convolutional neural networks were proposed recently, and Dense U-net as a new semantic segmentation network was successfully applied to scene segmentation. Retinal vessel is tiny, and the features of retinal vessel can be learned effectively by the patch-based learning strategy. In this study, we proposed a new retinal vessel segmentation framework based on Dense U-net and the patch-based learning strategy. In the process of training, training patches were obtained by random extraction strategy, Dense U-net was adopted as a training network, and random transformation was used as a data augmentation strategy. In the process of testing, test images were divided into image patches, test patches were predicted by training model, and the segmentation result can be reconstructed by overlapping-patches sequential reconstruction strategy. This proposed method was applied to public datasets DRIVE and STARE, and retinal vessel segmentation was performed. Sensitivity (Se), specificity (Sp), accuracy (Acc), and area under each curve (AUC) were adopted as evaluation metrics to verify the effectiveness of proposed method. Compared with state-of-the-art methods including the unsupervised, supervised, and convolutional neural network (CNN) methods, the result demonstrated that our approach is competitive in these evaluation metrics. This method can obtain a better segmentation result than specialists, and has clinical application value.

The same modality medical image registration with large deformation and clinical application based on adaptive diffeomorphic multi-resolution demons.

BACKGROUND: Diffeomorphic demons can not only guarantee smooth and reversible deformation, but also avoid unreasonable deformation. However, the number of iterations which has great influence on the registration result needs to be set manually. METHODS: This study proposed a novel method to exploit the adaptive diffeomorphic multi-resolution demons algorithm to the non-rigid registration of the same modality medical images with large deformation. Firstly an optimized non-rigid registration framework and the diffeomorphism strategy were used, and then a similarity energy function based on the grey value was designed as registration metric, lastly termination condition was set based on the variation of this metric and iterations can be stopped adaptively. Quantitative analyses based on the registration evaluation indexes were conducted to prove the validity of this method. RESULTS: Registration result of synthetic image and the same modality MRI and CT image was compared with those obtained by other demons algorithms. Quantitative analyses demonstrated the proposed method's superiority. Medical image with large deformation was produced by rotational distortion and extrusion transform, and the same modality image registration with large deformation was performed successfully. Quantitative analyses showed that the registration evaluation indexes remained stable with an increase in transform strength. This method can be also applied to pulmonary medical image registration with large deformation successfully, and it showed the clinical application value. The influence of different driving forces and parameters on the registration result was analysed, and the result demonstrated that the proposed method is effective and robust. CONCLUSIONS: This method can solve the non-rigid registration problem of the same modality medical image with large deformation showing promise for diagnostic pulmonary imaging applications.

Adaptive Diffeomorphic Multiresolution Demons and Their Application to Same Modality Medical Image Registration with Large Deformation.

Diffeomorphic demons can guarantee smooth and reversible deformation and avoid unreasonable deformation. However, the number of iterations needs to be set manually, and this greatly influences the registration result. In order to solve this problem, we proposed adaptive diffeomorphic multiresolution demons in this paper. We used an optimized framework with nonrigid registration and diffeomorphism strategy, designed a similarity energy function based on grey value, and stopped iterations adaptively. This method was tested by synthetic image and same modality medical image. Large deformation was simulated by rotational distortion and extrusion transform, medical image registration with large deformation was performed, and quantitative analyses were conducted using the registration evaluation indexes, and the influence of different driving forces and parameters on the registration result was analyzed. The registration results of same modality medical images were compared with those obtained using active demons, additive demons, and diffeomorphic demons. Quantitative analyses showed that the proposed method's normalized cross-correlation coefficient and structural similarity were the highest and mean square error was the lowest. Medical image registration with large deformation could be performed successfully; evaluation indexes remained stable with an increase in deformation strength. The proposed method is effective and robust, and it can be applied to nonrigid registration of same modality medical images with large deformation.

Frailty index and its associations with self-neglect, social support and sociodemographic characteristics among older adults in rural China.

AIM: The frailty index is used to measure the health status of older individuals. However, its association with self-neglect, social support and sociodemographic characteristics of older adults is underexplored. The purpose of the present study was to explore such associations among the rural older adults in Anhui Province of China, and to provide scientific evidence for policy-makers to improve the health and well-being of older adults in rural China. METHODS: A cross-sectional survey was undertaken among 3048 older adults in rural China. The frailty index was measured by an accumulation of deficits of 40 items. Ordinal logistic regression models were carried out to explore the associations of self-neglect, social support and sociodemographic characteristics with the frailty index. RESULTS: The frailty rate was 15.8% among the participants. Older adults who showed self-neglect, were female, had a lower education level, had a lower monthly income and did not drink alcohol were more prone to having frailty in the 60-76 years age group, whereas older adults who showed self-neglect, had poor social support, were female, were not smokers and did not drink alcohol were more likely to have frailty in the ≥77 years age group (P < 0.05). The interaction effect on frailty between self-neglect and social support was found in the 60-76 years age group. CONCLUSIONS: Age differences were shown in the associations between self-neglect, social support, sociodemographic characteristics and frailty index, which suggests different measures should be used accordingly for frailty prevention and management. Geriatr Gerontol Int 2018; 18: 987-996.

Chronic pain and its association with obesity among older adults in China.

OBJECTIVES: There is a paucity of epidemiological data on chronic pain and obesity among older adults. This study attempted to present the characterization of chronic pain and its association with obesity among the Chinese elderly. METHODS: A cross-sectional survey was undertaken among 6524 elderly individuals aged ≥60 years in China. Chronic pain was identified by self-reports based on the definition from the International Association for the Study of Pain (IASP). Body Mass Index (BMI) was measured to assess obesity. Binary logistic regression analysis was performed to explore the association between obesity and chronic pain. RESULTS: The prevalence of chronic pain was 49.8%. The legs/feet (25.5%), back (23.2%), and neck/shoulder (14.6%) were the most salient locations for chronic pain. Compared with normal weight, subjects with overweight (OR = 1.234, 95%CI = 1.100-1.384) and obesity (OR = 1.715, 95%CI = 1.418-2.073) were considerably more likely to have chronic pain after adjusting for covariates (p < .05). Age was not significantly associated with chronic pain (p > .05). Further analyses revealed that the associations between chronic pain and obesity were restricted to the legs/feet and back. CONCLUSION: Chronic pain is common among older adults in China. Understanding the role of obesity in chronic pain is important for preventing and treating chronic pain.

Risk factors of geriatric depression in rural China based on a generalized estimating equation.

ABSTRACTBackground:The number of elderly individuals living in China is increasing rapidly. The aim of this study was to examine the potential risk factors of geriatric depression in rural areas. METHODS: A repeated cross-sectional study was conducted between January 2015 and October 2016 in rural China. Nine hundred forty-five elderly individuals were included in both investigations. A generalized estimating equation (GEE) was used to examine the relationships between geriatric depression and socio-demographics, the number of chronic diseases, ADL (Activity of Daily Living) disability, cognitive impairment, and anxiety. RESULTS: Among the participants, the majority was female (61.4%) and illiterate (81.5%) and had a general economic status (63.0%) and more than two kinds of chronic diseases (62.9%). The bivariate analysis indicated that geriatric depression was associated with social support, education level, economic status, ADL disability, anxiety disorders, and cognitive impairment at both survey time points. The GEE results showed that poor economic status (OR = 8.294, p < 0.001), the presence of more than two chronic diseases (OR = 1.681, p = 0.048), ADL disability (OR = 2.184, p < 0.001), cognitive impairment (OR = 1.921, p < 0.001), and anxiety (OR = 5.434, p < 0.001) were risk factors for geriatric depression in rural China; better social support (OR = 0.924, 95% CI = 0.899-0.949, p < 0.001) was found to be a protective factor. CONCLUSIONS: Geriatric depression in rural China was associated with several socio-demographic, physical, and mental factors. Targeted interventions are essential to improve the psychological health of aged individuals in rural China.

The prevalence of molar incisor hypomineralization: evidence from 70 studies.

OBJECTIVE: A growing number of studies have investigated the prevalence of Molar Incisor Hypomineralization (MIH) around the world. The aim of this study was to systematically estimate the pooled prevalence of MIH. METHODS: A comprehensive literature research was completed in English and Chinese databases. Random effect models were used to calculate the pooled prevalence. To address the heterogeneity, meta-regression, and sensitivity analyzes were conducted. Publication bias was estimated by trim and fill method. RESULTS: Seventy eligible studies were included. The pooled prevalence of MIH was 14.2% globally. In subgroup analysis, South America (18.0%, 95% CI: 13.8-22.2) and Spain (21.1%, 95% CI: 17.7-24.6) had the highest prevalence. There was no significant difference between males (14.3%, 95% CI: 12.0-16.6) and females (14.4%, 95% CI: 12.8-15.9). The prevalence of MIH among children 10 years of age or younger (15.1%, 95% CI: 12.1-18.2) was much higher than the prevalence of MIH among older children (12.1%, 95% CI: 8.0-16.3). Sample size explained 15.7% heterogeneity. CONCLUSION: MIH has a high incidence globally, especially among children <10 years old. It is, therefore, imperative to develop more appropriate dental healthcare strategies to care for these children and to identify the etiology of MIH to prevent it occurring.

Effect of Cholesteryl Ester Transfer Protein Gene TaqIB Polymorphism on the Risk of Ischemic Stroke: A Meta-Analysis.

BACKGROUND: The association between cholesteryl ester transfer protein (CETP) TaqIB polymorphism and ischemic stroke (IS) risk has generated conflicting results. To investigate whether the TaqIB polymorphism of the CETP gene was associated with the risk of IS, a meta-analysis was performed. METHODS: Studies were retrieved by searching PubMed, Web of Science, the Chinese National Knowledge Infrastructure, the Chinese Wanfang Database, and the Chinese VIP Database before January 16, 2017. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were used to assess the association. Depending on the heterogeneity the fixed-effects model or the random-effects model was used. RESULTS: A total of 6 case-control studies were identified with 1494 cases and 1370 controls. Overall, an association of CETP TaqIB polymorphism with IS was found in the 4 genetic models (B2B2 versus B1B1: OR = .63, 95% CI = .51-.79, P < .001; B1B2 + B2B2 versus B1B1: OR = .75, 95% CI = .64-.87, P < .001; B2B2 versus B1B2 + B1B1: OR = .70, 95% CI = .57-.85, P < .001; B2 versus B1: OR = .78, 95% CI = .70-.87, P < .001). In the subgroup analysis by ethnicity, similar risks were also observed in Asian population. CONCLUSIONS: This meta-analysis indicates that CETP TaqIB polymorphism is associated with IS risk, and the B2 allele is a protective factor for IS.

Association of vitamin D receptor gene polymorphisms with susceptibility to childhood asthma: A meta-analysis.

BACKGROUND: As for the association of vitamin D receptor (VDR) gene polymorphisms with susceptibility to pediatric asthma, results of published studies yielded conflicts. A systematic review was conducted on the relationship between childhood asthma and VDR gene polymorphisms, including ApaI (rs7975232), BsmI (rs1544410), FokI (rs2228570), and TaqI (rs731236). METHODS: PubMed, Web of Science, CBM (Chinese Biomedical Database), CNKI (China National Knowledge Infrastructure), and Wanfang (Chinese) database were searched for relevant studies. Pooled odds ratios (OR) with 95% confidence interval (CI) were calculated. RESULTS: Overall results suggested that there was a statistically significant association between ApaI polymorphism and childhood asthma in homozygote model (OR = 1.674, 95%CI = 1.269-2.208, P < 0.001) and allele model (OR = 1.221, 95%CI = 1.084-1.375, P = 0.001). Stratification by ethnicity revealed a statistical association in Asians (OR = 1.389, 95%CI = 1.178-1.638, P < 0.001). There was some evidence of an association between BsmI polymorphism and childhood asthma in the homozygote (OR = 1.462, 95%CI = 1.016-2.105, P = 0.041) and allele models (OR = 1.181, 95%CI = 1.006-1.386, P = 0.042). This association reached significance only in the Caucasian group (OR = 1.236, 95%CI = 1.029-1.485, P = 0.023). For FokI, a statistical association was detected in dominant model (OR = 1.281, 95%CI = 1.055-1.555, P = 0.012); this association was significant in allele model (OR = 1.591, 95%CI = 1.052-2.405, P = 0.028) in Caucasian. CONCLUSION: ApaI polymorphism plays a particular role in childhood asthma in Asians. FokI polymorphism may be connected with pediatric asthma in Caucasian population. And BsmI polymorphism marginally contributes to childhood asthma susceptibility, while there might be no association between TaqI polymorphism and childhood asthma risk. Pediatr Pulmonol. 2017;52:423-429. © 2016 Wiley Periodicals, Inc.

Estimation of the cool executive function using frontal electroencephalogram signals in first-episode schizophrenia patients.

BACKGROUND: In schizophrenia, executive dysfunction is the most critical cognitive impairment, and is associated with abnormal neural activities, especially in the frontal lobes. Complexity estimation using electroencephalogram (EEG) recording based on nonlinear dynamics and task performance tests have been widely used to estimate executive dysfunction in schizophrenia. METHODS: The present study estimated the cool executive function based on fractal dimension (FD) values of EEG data recorded from first-episode schizophrenia patients and healthy controls during the performance of three cool executive function tasks, namely, the Trail Making Test-A (TMT-A), Trail Making Test-B (TMT-B), and Tower of Hanoi tasks. RESULTS: The results show that the complexity of the frontal EEG signals that were measured using FD was different in first-episode schizophrenia patients during the manipulation of executive function. However, no differences between patients and controls were found in the FD values of the EEG data that was recorded during the performance of the Tower of Hanoi task. CONCLUSIONS: These results suggest that cool executive function exhibits little impairment in first-episode schizophrenia patients.

Complete mitochondrial genome of the Eurasian siskin, Spinus spinus (Passeriformes: Fringillidae).

The Eurasian siskin (Spinus spinus), also called the European siskin, common siskin or just siskin, is found throughout Europe and Asia. In this study, the complete mitochondrial genome of S. spinus was determined to be 16,828 bp. The size of protein-coding genes (PCGs) in the S. spinus mitochondrial genome was 11,400 bp. The longest PCG of S. spinus mtDNA was nad5 (1818 bp), whereas the shortest is atp8 (168 bp). The nad6 gene of S. spinus mitogenome had strong skews of T versus A (-0.54), and G versus C (0.64). According to the distribution of the conserved motifs in other avian CRs, the CR of S. spinus can be divided into three domains: ETAS domain I, central conserved domain II, and CSB domain III.

Complete mitochondrial genome of the Blue Eared Pheasant, Crossoptilon auritum (Galliformes: Phasianidae).

The circular mitochondrial genome of Crossoptilon auritum is 16,687 bp in length, containing 13 protein-coding genes (PCGs), 2 ribosomal RNA genes, 22 transfer RNA (tRNA) genes, and a putative control region. All of the genes encoded on the H-strand, except for one PCG (nad6) and eight tRNA genes (tRNA(Gln), tRNA (Ala), tRNA (Asn), tRNA(Cys), tRNA(Tyr), tRNA(Ser)((UCN)), tRNA(Pro), and tRNA(Glu)), as found in many other birds' mitochondrial genomes. All of these PCGs are initiated with ATG, except for cox1 and nad5, which began with GTG, while stopped by four types of stop codons. All tRNA genes have the potential to fold into typical clover-leaf structure. Phylogenetic analysis indicated that the genus Crossoptilon was the sister of the genus Lophura.

Characterization of the complete mitochondrial genome of Collared Finchbill, Spizixos semitorques (Passeriformes: Pycnonotidae).

The complete mitochondrial genome of Spizixos semitorques is 17,045 bp long with an A+T content of 55.52%, which composed of 13 typical protein-coding genes, 22 transfer RNA (tRNA) genes, 2 ribosomal RNA (rRNA) genes, and 2 extensive heteroplasmic control regions (CR1 and CR2). Genome organization of S. semitorques is similar to that of other birds. All of the PCGs started with ATG, except for cox1, which began with GTG. Six types of termination codons were used, canonical TAA and TAG termination codons are found in seven protein-coding genes, while AGA for nad1 and nad5, AGG for cox1, and the remaining genes (nad2, cox3, nad4) have incomplete termination codons (TA- or T- -). All tRNA genes have a typical clover-leaf structure. Furthermore, a minisatellite of 24 nucleotides (5'-CACAAAAATCAAACAAAAATACAA-3') with 2.9 tandem repeats at the end of CR2 were detected.