Preliminary study of short-term outcomes and learning curves of robotic-assisted THA: comparison between closed platform robotic system and open platform robotic system.

BACKGROUND: Both closed platform and open platform robotic-assisted total hip arthroplasty (THA) have recently been recommended as a viable treatment option for achieving accurate positioning of components. Yet, limited studies paid attention to the differences between the closed platform robotic system and the open platform robotic system. Hence, this study aimed to investigate clinical outcomes, radiographic outcomes, complication rates and learning curve of two systems. MATERIALS AND METHODS: We retrospectively included 62 patients (31 closed robotic system and 31 open robotic system) who underwent THA between February 2021 and January 2023. The demographics, operating time, cup positioning, complications and hip Harris score were evaluated. Learning curves of operation time was conducted using cumulative sum (CUSUM) analysis. RESULTS: There were no differences in surgical time (76.7 ± 12.1 min vs. 72.3 ± 14.8 min), estimated blood loss (223.2 ± 13.2 ml vs. 216.9 ± 17 ml) and Harris Hip score (HHS) between closed platform robotic system and the open platform robotic system. The closed robotic system and the open robotic system were associated with a learning curve of 9 cases and 7 cases for surgical time respectively, based on the satisfying rate of Lewinnek's safe zone outliers (1/31, 96.8%) and no occurrence of complication. Both robotic systems had significant reduction in overall surgical time, the duration of acetabulum registration, and estimated blood loss between learning phase and proficiency phase. CONCLUSION: The authors suggest that the surgical outcomes and safe zone outlier rate of the open robotic-assisted THA were similar to those of the closed robotic-assisted THA. These two robotic-assisted are associated with comparable learning curves and both have the precise positioning of acetabular component. From learning phase to proficiency phase, the rate of positions within the safe zone differed only marginally (88.9-100% vs. 85.7-100%) based on a rather low number of patients. This is not a statistically significant difference. Therefore, we suggest that THA undergoing with the robotic-assisted system is the relatively useful way to achieve planned acetabular cup position so far.

Outcomes of dual mobility articulation total hip arthroplasty in ipsilateral residual poliomyelitis.

BACKGROUND: Patients with poliomyelitis underwent total hip arthroplasty (THA) are known to be at higher risk of dislocation on account of muscular atrophy. This study aimed to investigate clinical outcomes, radiographic outcomes, complication rates, and survivorship of dual mobility THA in displaced femoral neck fractures of elderly with poliomyelitis. MATERIALS AND METHODS: We retrospectively included 17 patients (17 hips) with residual poliomyelitis who underwent THA with dual mobility articulation. Clinical outcomes were assessed with the visual analog scale (VAS) pain score, Oxford hip score, and University of California Los Angeles activity (UCLA) score. Radiographic outcomes were examined by radiographs. Complications and re-operations following THA were recorded. RESULTS: The mean follow-up period was 77.05 months. The mean VAS, Oxford hip score, and UCLA score were improved significantly. In all but one patient, no complications were occurred. Re-operation was carried out in one patient due to posterior dislocation. The Kaplan-Meier survivorship with an end point of re-operation for any reason was 94.1%. CONCLUSIONS: THA with dual mobility system is proved to be effective in strengthening stability and reducing the risk of dislocation, which is suitable for patients with neuromuscular disease. Hence, in elderly with residual poliomyelitis, dual mobility THA is a valid choice as a treatment for displaced femoral neck fractures.

The role of routine postoperative laboratory tests following hip hemiarthroplasty for an elderly femoral neck fracture.

BACKGROUND: Performing postoperative laboratory tests following joint arthroplasty is a regular practice. However, the role of routine postoperative laboratory tests in primary hip arthroplasty is currently in doubt. This study aimed to assess the role of routine postoperative laboratory tests for femoral neck fractures in elderly patients who underwent hip hemiarthroplasty and to evaluate the risk factors for postoperative laboratory testing abnormalities and related interventions. METHODS: This retrospective study reviewed 735 consecutive patients with femoral neck fractures (FNFs) who underwent hip hemiarthroplasty at a single tertiary academic organization. Patient characteristic features and laboratory testing values were recorded. Logistic regression models were calculated to identify risk factors. RESULTS: A total of 321 elderly patients (> 75 years of age) were ultimately enrolled for analysis. Abnormal postoperative laboratory tests were found in 265 patients (82.6%). Only a minority of the included patients (7.5%) needed medical intervention to treat postoperative laboratory testing abnormalities. Multivariate logistic regression analysis reported that a higher Charlson comorbidity index (CCI) (P = 0.03), abnormal preoperative haemoglobin level (P < 0.01), higher intraoperative blood loss (P < 0.01) and less frequent tranexamic acid use (P = 0.05) were risk factors for abnormal postoperative laboratory tests. Furthermore, a higher CCI has been identified as a risk factor for patients needing clinical interventions related to laboratory abnormalities. CONCLUSIONS: Because 92.5% of laboratory tests did not influence postoperative management, the authors suggest that routine laboratory tests after hip hemiarthroplasty for FNFs are less instructive for the majority of elderly patients. Nevertheless, for patients with identified risk factors, postoperative laboratory tests are still required to identify the abnormalities that need to be managed.

Comparative transcriptomic analysis of fireflies (Coleoptera: Lampyridae) to explore the molecular adaptations to fresh water.

Aquatic insects are well adapted to freshwater environments, but the molecular basis of these adaptations remains largely unknown. Most firefly species (Coleoptera: Lampyridae) are terrestrial, but the larvae of several species are aquatic. Here, larval and adult transcriptomes from Aquatica leii (freshwater) and Lychnuris praetexta (terrestrial) were generated to test whether the genes associated with metabolic efficiency and morphology have undergone adaptive evolution to fresh water. The aquatic fireflies had a significantly lower ratio of nonsynonymous to synonymous substitutions than the terrestrial insects, indicating a genomewide evolutionary constraint in the aquatic fireflies. We identified 341 fast-evolving genes and 116 positively selected genes in the aquatic fireflies. Of these, 76 genes exhibiting both fast evolution and positive selection were primarily involved in ATP production, energy metabolism and the hypoxia response. We identified 7,271 differentially expressed genes (DEGs) in A. leii (adults versus larvae) and 8,309 DEGs in L. praetexta (adults versus larvae). DEGs specific to the aquatic firefly (n = 1,445) were screened via interspecific comparisons (A. leii versus L. praetexta) and were significantly enriched for genes involved in metabolic efficiency (e.g., ATP production, hypoxia, and immune responses) and certain aspects of morphology (e.g., cuticle chitin, tracheal and compound eye morphology). These results indicate that sequence and expression-level changes in genes associated with both metabolic efficiency and morphological attributes related to the freshwater lifestyle contributed to freshwater adaptation in fireflies. This study provides new insights into the molecular mechanisms of aquatic adaptation in insects.

MicroRNA profile of immune response in gills of zebrafish (Danio rerio) upon Staphylococcus aureus infection.

The gills of fish are large mucosal surfaces that are very important portals for pathogen entry. Investigations have shown that microRNAs (miRNAs) are key regulators of immune response to bacterial infections in the gills of fish; however, how miRNA expression changes in response to infection by Gram-positive bacteria remains largely unknown. To further investigate the immunological role of miRNAs in fish gills under pathogen stress induced by Gram-positive bacterial infection, this study investigated Staphylococcus aureus (SA)-induced changes in the miRNAs levels in gills of adult zebrafish (Danio rerio). miRNA microarrays were used to analyze expression profiles of known miRNA in the gills of zebrafish in response to SA infection and compared these to uninfected control fish. A total of 30 differentially expressed miRNAs (DEMs) were identified. Target genes likely regulated by DEMs were predicted, and functional enrichment analyses were performed. The results indicated that DEM targets were primarily involved in innate immune processes, apoptosis, defense responses, and antibacterial responses. Pathways involving bacterial infection, innate immunity, metabolic process, disease, and apoptosis were mediated by DEMs. Furthermore, real-time quantitative PCR experiments for nine key SA-responsive DEMs that regulated the "SA infection" pathway validated the accuracy of microarray results. Dynamic variations in gene expression were surveyed in detail for these key SA-responsive DEMs for PBS control and at 6, 12, 24, and 48 h after SA challenge in detail. This study provides novel insight into the mechanisms underlying the miRNA regulation during the SA-induced immune response in zebrafish gills, and provides basic knowledge on the innate immune response against Gram-positive bacterial infection in bony fish.

Identification of circular RNAs and their altered expression under poly(I:C) challenge in key antiviral immune pathways in amphioxus.

Amphioxus is a key model for studying comparative immunity of vertebrates. Circular RNA (circRNA), as RNAs with a circular structure, has received little attention until recently, where several studies have reported that circRNA expression changes are involved in the immune response in animals. However, circRNA and its immune role in amphioxus have not been previously studied. Here, circRNAs in Chinese amphioxus (Branchiostoma belcheri) were sequenced, and 1859 circRNAs were identified using two algorithms (find_circ and CIRI). The analysis of miRNA target sites on circRNAs showed that 332 circRNAs may function as miRNA sponges. Furthermore, we identified circRNAs that were conserved between B. belcheri and vertebrates, tracing the origin of these circRNAs within chordates. Additionally, in combination with several key antiviral immune (poly(I:C), pIC) pathways identified in our previous B. belcheri studies, nine circRNAs potentially involved in these pathways were identified using bioinformatic predictions. Among these nine circRNAs, eight were selected to examine their expression response in B. belcheri challenged by pIC in comparison to control using real-time quantitative PCR. The results showed that four circRNAs were induced as part of the antiviral response against pIC, while expression of two circRNAs was decreased, and the expression levels of the remaining two were not significantly altered after pIC challenge. This work is the first to identify circRNAs and reveal their antiviral role in amphioxus. Therefore, it opens a new window to explore the comparative immunology of circRNAs in chordates and the regulatory roles of circRNAs in antiviral immunity in amphioxus.

Comparative transcriptomic analysis provides insights into antibacterial mechanisms of Branchiostoma belcheri under Vibrio parahaemolyticus infection.

Amphioxus, a basal chordate, is widely considered to be an existing proxy of the invertebrate ancestor of vertebrates, and it exhibits susceptibility to various pathogen infections and pathogenic mimic challenges. Here, in order to understand more clearly its antibacterial mechanisms, we analyzed the ribosomal RNA (rRNA)-depleted transcriptome of Chinese amphioxus (Branchiostoma belcheri) infected with Vibrio parahaemolyticus (V. p.) via next-generation deep sequencing technology (RNA-seq). We identified a total of 3214 differentially expressed genes (DEGs) by comparing V. p.-infected and control transcriptome libraries, including 2219 significantly up-regulated and 995 significantly down-regulated DEGs in V. p.-infected amphioxus. The DEGs with the top 10 most dramatic expression fold changes after V. p. infection, as well as 53 immune-related DEGs (IRDs) belonging to four primary categories of innate immunity were analyzed further. Through gene ontology (GO) and pathway enrichment analysis, DEGs were found to be primarily related to immune processes, apoptosis, catabolic and metabolic processes, binding and enzyme activity, while pathways involving bacterial infection, immune signaling, immune response, cancer, and apoptosis were overrepresented. We validated the RNA-seq results by detecting the expression levels of 10 IRDs using qRT-PCR, and we surveyed the dynamic variation in gene expression for these IRDs at 0, 6, 12, 24, and 48 h after V. p. TREATMENT: Subsequently, according to the RNA-seq results, the presence of a primitive Toll-like receptor (TLR)-mediated antibacterial immune signaling pathway was predicted in B. belcheri. This study provides valuable information regarding antibacterial immunity for further research into the evolution of immunity in vertebrates and broadens our understanding of the innate immune response against bacterial invasion in amphioxus.

Exploring gene expression changes in the amphioxus gill after poly(I:C) challenge using digital expression profiling.

Amphioxus, a cephalochordate, is a key model animal for studying the evolution of vertebrate immunity. Recently, studies have revealed that microRNA (miRNA) expression profiles change significantly in the amphioxus gill after immune stimulation, but it remains largely unknown how gene expression responds to immune stress. Elucidating gene expression changes in the amphioxus gill will provide a deeper understanding of the evolution of gill immunity in vertebrates. Here, we used high-throughput RNA sequencing technology (RNA-seq) to conduct tag-based digital gene expression profiling (DGE) analyses of the gills of control Branchiostoma belcheri and of those exposed to the viral mimic, poly(I:C) (pIC). Six libraries were created for the control and treatment groups including three biological replicates per group. A total of 1999 differently expressed genes (DEGs) were obtained, with 571 and 1428 DEGs showing up- or down-regulation, respectively, in the treatment group. Enrichment analysis of gene ontology (GO) terms and pathways revealed that the DEGs were primarily related to immune and defense response, apoptosis, human disease, cancer, protein metabolism, enzyme activity, and regulatory processes. In addition, eight DEGs were randomly selected to validate the RNA-seq data using real-time quantitative PCR (qRT-PCR), and the results confirmed the accuracy of the RNA-seq approach. Next, we screened eight key responding genes to examine the dynamic changes in expression levels at different time points in more detail. The results indicated that expressions of TRADD, MARCH, RNF31, NF-κb, CYP450, TNFRSF6B, IFI and LECT1 were induced to participate in the antiviral response against pIC. This study provides a valuable resource for understanding the role of the amphioxus gill in antiviral immunity and the evolution of gill immunity in vertebrates.

Genome-wide gene expression analysis of amphioxus (Branchiostoma belcheri) following lipopolysaccharide challenge using strand-specific RNA-seq.

Amphioxus is the closest living proxy for exploring the evolutionary origin of the immune system in vertebrates. To understand the immune responses of amphioxus to lipopolysaccharide (LPS), 5 ribosomal RNA (rRNA)-depleted libraries of amphioxus were constructed, including one control (0 h) library and 4 treatment libraries at 6, 12, 24, and 48 h post-injection (hpi) with LPS. The transcriptome of Branchiostoma belcheri was analyzed using strand-specific RNA sequencing technology (RNA-seq). A total of 6161, 6665, 7969, and 6447 differentially expressed genes (DEGs) were detected at 6, 12, 24, and 48 hpi, respectively, compared with expression levels at 0 h. We identified amphioxus genes active during the acute-phase response to LPS at different time points after stimulation. Moreover, to better visualize the resolution phase of the immune process during immune response, we identified 6057 and 5235 DEGs at 48 hpi by comparing with 6 and 24 hpi, respectively. Through real-time quantitative PCR (qRT-PCR) analysis of 12 selected DEGs, we demonstrated the accuracy of the RNA-seq data in this study. Functional enrichment analysis of DEGs demonstrated that most terms were related to defense and immune responses, disease and infection, cell apoptosis, and metabolism and catalysis. Subsequently, we identified 1330, 485, 670, 911, and 1624 time-specific genes (TSGs) at 0, 6, 12, 24, and 48 hpi. Time-specific terms at each of 5 time points were primarily involved in development, immune signaling, signal transduction, DNA repair and stability, and metabolism and catalysis, respectively. As this is the first study to report the transcriptome of an organism with primitive immunity following LPS challenge at multiple time points, it provides gene expression information for further research into the evolution of immunity in vertebrates.

Genome-wide transcriptomics and microRNAomics analyses uncover multi-faceted mechanisms to cope with copper stress in ancient macrobenthos amphioxus.

The mechanisms underlying the toxicity of environmental stress are unclear for marine macrobenthos. Copper/Cu has posed the most serious threats to amphioxus, an ancient and model benthic cephalochordate. Herein, a dynamic change in the physiological parameters (GR, SOD, ATP, and MDA) was detected with ROS accumulation in Branchiostoma belcheri exposed to 0.3 mg·L-1 Cu. Transcriptomes and microRNAomes of B. belcheri were generated to investigate the molecular mechanisms by which this amphioxus copes with Cu exposure. Time-specific genes identified at different time points after exposure were involved in the stimulus and immune response, detoxification and ionic homeostasis, aging and the nervous system, sequentially, with prolongation of exposure time, forming a dynamic process of molecular response to Cu stress. In total, 57 differentially expressed miRNAs were identified under Cu stress. Transcriptomics-miRNAomics analyses indicate that these miRNAs targeted genes associated with many key biological processes such as xenobiotics degradation, oxidative stress, and energy metabolism. The constructed miRNA-mRNA-pathway network uncovered a broad post-transcriptional regulatory mechanism in B. belcheri to cope with Cu stress. Overall, this integrated analyses show that enhanced defense response, accelerated ROS elimination, and repressed ATP production constitute a comprehensive strategy to cope with Cu toxicity in the ancient macrobenthos.

Complex embryos displaying bilaterian characters from Precambrian Doushantuo phosphate deposits, Weng'an, Guizhou, China.

Three-dimensionally preserved embryos from the Precambrian Ediacaran Doushantuo Formation, Weng'an, Guizhou, southern China, have attracted great attention as the oldest fossil evidence yet found for multicellular animal life on Earth. Many embryos are early cleavage embryos and most of them yield a limited phylogenetic signal. Here we report the discovery of two Doushantuo embryos that are three-dimensionally preserved and complex. Imaging techniques using propagation phase-contrast based synchrotron radiation microtomography (PPC-SR-microCT) reveal that the organization of cells demonstrates several bilaterian features, including the formation of anterior-posterior, dorso-ventral, and right-left polarities, and cell differentiation. Unexpectedly, our observations show a noticeable difference in organization patterns between the embryos, suggesting that they represent two distinct taxa. These embryos provide further evidence for the presence of bilaterian animals in the Doushantuo biota. Furthermore, these bilaterians had already diverged into distantly related groups at least 40 million years before the Cambrian radiation, indicating that the last common ancestor of the bilaterians lived much earlier than is usually thought.

Genome-Wide Expression Difference of MicroRNAs in Basal Cell Carcinoma.

Distinct expression of the miRNAs has rarely been explored in basal cell carcinoma (BCC) of skin, and the regulatory role of miRNAs in BCC development remains quite opaque. Here, we collected control tissues from adjacent noncancerous skin (n = 15; control group) and tissues at tumor centers from patients with cheek BCC (n = 15; BCC group) using punch biopsies. After six small RNA sequencing- (sRNA-seq-) based miRNA expression profiles were generated for both BCC and controls, including three biological replicates, we conducted comparative analysis on the sRNA-seq dataset, discovering 181 differentially expressed miRNAs (DEMs) out of the 1,873 miRNAs in BCCs. In order to validate the sRNA-seq data, expression of 15 randomly selected DEMs was measured using the TaqMan probe-based quantitative real-time PCR. Functional analysis of predicted target genes of DEMs in BCCs shows that these miRNAs are primarily involved in various types of cancers, immune response, epithelial growth, and morphogenesis, as well as energy production and metabolism, indicating that BCC development is caused, at least in part, by changes in miRNA regulation for biological and disease processes. In particular, the "basal cell carcinoma pathways" were found to be enriched by predicted DEM targets, and regulatory relationships between DEMs and their targeted genes in this pathway were further uncovered. These results revealed the association between BCCs and abundant miRNA molecules that regulate target genes, functional modules, and signaling pathways in carcinogenesis.

Diabetes mellitus accelerates the progression of osteoarthritis in streptozotocin-induced diabetic mice by deteriorating bone microarchitecture, bone mineral composition, and bone strength of subchondral bone.

BACKGROUND: The purpose of this study was to develop an optimal diabetes-osteoarthritis (DM-OA) mouse model to validate that diabetes aggravates osteoarthritis (OA) and to evaluate the microarchitecture, chemical composition, and biomechanical properties of subchondral bone (SB) as a consequence of the DM-OA-induced damage induced. METHODS: Mice were randomly divided into three groups: DM-OA group, OA group, and sham group. Blood glucose levels, body weight, and food intake of all animals were recorded. Serum calcium (Ca) and osteocalcin (OCN) levels were compared in the three groups. The messenger ribonucleic acid (mRNA) and protein expression of key regulators for bone metabolism were detected. A semi-quantitative grading system [Osteoarthritis Research Society International (OARSI)] was used to evaluate cartilage and SB degeneration. Microspectroscopy, microindentations, micro-computed tomography (CT) imaging, and fracture load of compression testing were also used to evaluate trabecular SB properties. RESULTS: Glycemic monitoring and pancreas pathological results indicated stable high blood glucose and massive destruction of pancreas and islet cells in the DM-OA group. Serum levels of bone specific alkaline phosphatase (ALP-B) and tartrate-resistant acid phosphatase 5b (TRACP-5b) in the DM-group were higher than those of the other two groups while levels of serum Ca and OCN were lower. Meanwhile, the protein and mRNA expression of osteoblast-specific biomarkers [osteoprotegerin/receptor activator of nuclear factor kappa-B ligand (OPG/RANKL) ratio, collagen type I (COL-I), Runt-related transcription factor 2 (RUNX-2), OCN] were suppressed, and osteoclast-specific biomarkers [sclerostin (SOST)] was elevated in the DM-OA group. The mineral-to-collagen ratio, microindentation elastic modulus, hardness, micro-architectural parameters, bone mineral density, and fracture load of SB trabecular bone of the DM-OA group joint were lower than those of the other two groups. On the other hand, The OARSI score, trabecular spacing, and structural model index of the DM-OA group joint were higher than those of the other two groups. CONCLUSIONS: The glycemic and pancreatic pathological results indicated that the DM-OA model was a simple and reliable model induced by streptozotocin (STZ) and surgery. The results revealed the mechanisms through which diabetes accelerates OA; that is, by damaging and deteriorating the functions of SB, including its microarchitecture, chemical composition, and biomechanical properties.

Hemiarthroplasty compared with internal fixation for treatment of nondisplaced femoral neck fractures in elderly patients: a retrospective study.

INTRODUCTION: Internal fixation (IF) with cannulated screws is the most widely accepted operation method for nondisplaced femoral neck fractures (FNFs) in elderly patients. However, there were higher rate of reoperation, severe complications and poorer functional outcomes reported in these patients treated with IF. The purpose of this research is to compare the prognosis, complications, reoperation and mortality of bipolar hemiarthroplasty (HA) with IF of cannulated screws in elderly patients. METHODS: All elderly patients (>75 years of age) with nondisplaced FNFs from January 2010 to December 2015 at our institution were included in this study. Patients treated with HA and IF with cannulated screws were compared. Outcome measures included the surgical complications, perioperative parameters, hip joint function, reoperation and mortality. RESULTS: The blood loss of HA group (150.0 ± 55.1 mL) was statistically more than IF group (40.5 ± 15.7 mL, p = 0.001). However, the blood transfusion rate was similar between two groups (p = 0.102). At the last follow-up, there were total 14 (34.1%) severe surgical complications in the IF group, compared to 9 (10.1%) in the HA group (P = 0.001). No difference was detected between two groups with respect to the HHS and VAS at the last follow-up. Compared with the HA group, the IF group had much more reoperation in the follow up period (p = 0.001). There was no statistically differences of mortality rate between HA group (39.3%, 35/89) and IF group (34.1%, 14/41) (p=0.571). CONCLUSIONS: As a treatment option for nondisplaced intracapsular FNFs in elderly patients, HA showed the merits of a less surgical complications and less reoperations, while IF demonstrated a shorter surgical time and less intraoperative blood loss. Meanwhile, there was no significant difference in the hip joint function and mortality rate in midterm follow-up. Further evaluation with a longer follow-up is recommended to strengthen these findings.

Adaptive evidence of mitochondrial genomes in Dolycoris baccarum (Hemiptera: Pentatomidae) to divergent altitude environments.

Given mitochondrion is the 'energy and oxygen usage factories', adaptive signatures of mitochondrial genes have been extensively investigated in vertebrates from different altitudes, but few studies focus on insects. Here, we sequenced the complete mitochondrial genome (mitogenome) of Dolycoris. baccarum living in the Tibetan Plateau (DBHC, ∼3200 m above sea level (asl)) and conducted a detailed comparative analysis with another D. baccarum mitogenome (DBQY) from relatively low altitude (∼1300 m asl). All the 37 mitochondrial genes were highly conserved and under purifying selection, except for two mitochondrial protein-coding genes (MPCGs) (atp6 and nad5) that showed positively selected signatures. We therefore further examined non-synonymous substitutions in atp6 and nad5, by sequencing more individuals from three populations with different altitudes. We found that these non-synonymous substitutions were polymorphic in these populations, likely due to relaxed selection constraints in different altitudes. Purifying selection in all mitochondrial genes may be due to their functional importance for the precision of ATP production usually. Length difference in mitochondrial control regions between DBHC and DBQY was also conversed at the population level, indicating that sequence size adjustments in control region may be associated with adaptation to divergent altitudes. Quantitatively real-time PCR analysis for 12 MPCGs showed that gene expression patterns had a significant change between the two populations, suggesting that expression levels of MPCGs could be modulated by divergent environmental pressures (e.g. oxygen content and ambient temperature). These results provided an important guide for further uncovering genetic mechanisms of ecological adaptation in insects.

Comparative transcriptomic analysis provides insights into the response to the benzo(a)pyrene stress in aquatic firefly (Luciola leii).

Many studies have reported that behavior and bioluminescence of fireflies could be affected by changes in environment conditions. However, little is known about how the deterioration of the aquatic environment affects aquatic fireflies, particularly with respect to molecular responses following exposure to water pollutants, such as benzo(a)pyrene (BaP), which is a key indicator in environmental risk assessment because of the hazards it poses. Here, whole transcriptome sequencing and gene expression analysis were performed on freshwater fireflies (Luciola leii) exposed to BaP (concentration of 0.01 mg/L). Four transcriptomic libraries were constructed for the control and treatment groups, including two biological replicates. From the mixed pools (each pool contains 60 individuals from three time points), a total of 54,282 unigenes were assembled. Furthermore, 329,337 of Single-nucleotide Polymorphisms (SNPs) and 1324 of Simple Sequence Repeats (SSRs) were predicted using bioinformatics, which is useful for the future development of molecular markers. Subsequently, 2414 differently expressed genes (DEGs) were identified in response to BaP stress in comparison to the control, including 1350 up-regulated and 1064 down-regulated DEGs. Functional enrichment showed that these DEGs are primarily related to innate immunity; xenobiotic biodegradation and response, biomacromolecule metabolism, biosynthesis, and absorption. Eight key BaP-responsive DEGs were screened to survey the dynamic changes of expression in response to BaP stress at different time points, and to validate the RNA sequencing data using quantitative real-time PCR. The results indicate that the expression of genes encoding UGT, CYP3A, CYP9, CYP6AS5 and ADHP were induced, while those encoding UGT2B10L, PTGDS, and ALDH were reduced, to participate in response to the BaP exposure and potentially help counteract the adverse effects of BaP. This investigation provides insight into the toxicological response of fireflies to the occurrence of water deterioration.

Genome-Wide Identification and Transcriptomic Analysis of MicroRNAs Across Various Amphioxus Organs Using Deep Sequencing.

Amphioxus is the closest living invertebrate proxy of the vertebrate ancestor. Systematic gene identification and expression profile analysis of amphioxus organs are thus important for clarifying the molecular mechanisms of organ function formation and further understanding the evolutionary origin of organs and genes in vertebrates. The precise regulation of microRNAs (miRNAs) is crucial for the functional specification and differentiation of organs. In particular, those miRNAs that are expressed specifically in organs (OSMs) play key roles in organ identity, differentiation, and function. In this study, the genome-wide miRNA transcriptome was analyzed in eight organs of adult amphioxus Branchiostoma belcheri using deep sequencing. A total of 167 known miRNAs and 23 novel miRNAs (named novel_mir), including 139 conserved miRNAs, were discovered, and 79 of these were identified as OSMs. Additionally, analyses of the expression patterns of eight randomly selected known miRNAs demonstrated the accuracy of the miRNA deep sequencing that was used in this study. Furthermore, potentially OSM-regulated genes were predicted for each organ type. Functional enrichment of these predicted targets, as well as further functional analyses of known OSMs, was conducted. We found that the OSMs were potentially to be involved in organ-specific functions, such as epidermis development, gonad development, muscle cell development, proteolysis, lipid metabolism, and generation of neurons. Moreover, OSMs with non-organ-specific functions were detected and primarily include those related to innate immunity and response to stimuli. These findings provide insights into the regulatory roles of OSMs in various amphioxus organs.

Genome-wide transcriptional response of microRNAs to the benzo(a)pyrene stress in amphioxus Branchiostoma belcheri.

Amphioxus, a cephalochordate found in sand habitats in shallow in-shore seawaters, has been widely used as a model in comparative immunology of chordates. However, the role of microRNAs (miRNAs) in amphioxus under abiotic stress, particularly xenobiotics with strong toxicity, remains largely unknown. Here, a widespread marine contaminant, benzo(a)pyrene (BaP) is used to evaluate its toxic effects on miRNA expression of amphioxus. Six small RNA libraries were sequenced from Branchiostoma belcheri. A total of 144 known and 157 novel miRNAs were identified using deep sequencing and bioinformatics approaches. A total of 58 differentially expressed miRNAs (DEMs) were screened, including 25 up- and 33 down-regulated DEMs under BaP stress. Target genes possibly regulated by DEMs were predicted, and their functional enrichment analyses were performed. Targets of DEMs are primarily involved in xenobiotic and cellular homeostasis, catabolic and transport process. They could be largely linked to nine immune- and toxin detoxification-related pathways, including metabolism of xenobiotics by cytochrome P450, drug metabolism-other enzymes, and drug metabolism-cytochrome P450, etc. Furthermore, quantitative real-time PCR (qRT-PCR) analysis for 12 key BaP-responsive DEMs validates the accuracy of deep sequencing. Experiments were then conducted to investigate their expression responses to BaP stress at different time intervals in detail to further determine their expression dynamic in responses of B. belcheri towards BaP exposure. This study, to the best of our knowledge, investigates the regulatory roles of miRNAs in the toxicological response of amphioxus for the first time, providing valuable information for the protection of lone existing cephalochordate amphioxus.

Genome-wide gene expression analysis reveals novel insights into the response to nitrite stress in gills of Branchiostoma belcheri.

Amphioxus has been widely used as a model for the comparative immunology of vertebrates. Studies have reported that gene expression changes in the amphioxus gill in response to biotic stress, such as microbial and their mimic challenge, but little is known about how gene expression is affected by abiotic stress in the marine environment, such as nitrite. A lack of information regarding gene expression response to abiotic stress hinders a comprehensive understanding of gill defense response in amphioxus. Here, RNA sequencing was used to carry out gene expression profiling analyses of Branchiostoma belcheri gills under nitrite stress. Six libraries were created for the control and treatment groups, including three biological replicates. In total, 2416 differently expressed genes (DEGs) were detected in response to nitrite stress, of which 1522 DEGs were up-regulated in the treatment group in comparison to the control, while the remaining 894 DEGs were down-regulated genes. Functional enrichment revealed that these DEGs are primarily involved in disease, innate immunity, xenobiotic biodegradation and metabolism, and biomolecular processes and apoptosis. We screened 11 key nitrite-responsive DEGs to detect their expression responses to nitrite stress at different time points, and validate the sequencing data using real time quantitative PCR. The results indicated that the expression of gene encoding CYP3A, POD, CASPR1, GST, MAO, DDH, and XDH/XO were induced, while those encoding MRC, GT, DNASE1L, and RIPK5 were reduced, to participate in the anti-nitrite response. This study provides a useful resource for research of molecular toxicology in amphioxus under environmental stress.

Early crest animals and the insight they provide into the evolutionary origin of craniates.

The Cristozoa (also known as crest animals) are established as representing the animals containing neural crest and its derivatives, constituting all known craniates and their immediate precraniate precursors. The precraniate crest animals all are extinct and preserved only in Early Cambrian strata of Yunnan (southwestern China). Fine anatomical details of Haikouella and the slightly more advanced species Yunnanozoon exhibit many characters unique to vertebrates, but they lack a skull and most other elaborated placodal and neural crest derivations, throwing novel light onto the previously missing history at the very beginning of cristozoan evolution. Comparative study with the cephalochordate amphioxus suggests that precraniate evolution is marked by a series of innovations including: muscular ventilation with gill-bearing and jointed brachial arches, paired head sensorial organs including paired eyes and nostrils, relatively large, slightly differentiated brain, protovertebrae, and some derivatives of neural crest cells. But, they lack ears, a clear telencephalon, and a skull. Furthermore, comparison of the brains of amphioxus and craniates suggests that the tripartite brain with telencephalon was not an older structure but a novelty of the craniates.