Novel Germline KIT Variants in Families With Severe Piebaldism: Case Series and Literature Review.

INTRODUCTION: Piebaldism is a rare autosomal dominant disorder characterized by congenital white forelock and depigmented patches, which is most commonly caused by deleterious variants in the KIT gene. METHODS: Four KIT variants were identified in a piebaldism case series by whole-exome sequencing. Functional experiments, including in vitro minigene reporter assay and enzyme-linked immunosorbent assay, were carried out to elucidate the pathogenicity of the variants. The genotype-phenotype correlation was summarized through extensive literature reviewing. RESULTS: All the four cases had severe piebaldism presented with typical white forelock and diffuse depigmentation on the ventral trunk and limbs. Four germline variants at the tyrosine kinase (TK) domains of the KIT gene were identified: two novel variants c.1990+1G>A (p.Pro627_Gly664delinsArg) and c.2716T>C (p.Cys906Arg), and two known variants c.1879+1G>A (p.Gly592_Pro627delinsAla) and c.1747G>A (p.Glu583Lys). Both splicing variants caused exon skipping and inframe deletions in the TK1 domain. The missense variants resided at the TK1 and TK2 domains respectively impairing PI3K/AKT and MAPK/ERK signaling pathways, the downstream of KIT. All severe cases were associated with variants in the TK domains, eliciting a major dominant-negative mechanism of the disease. CONCLUSION: Our data expand the mutation spectrum of KIT, emphasized by a dominant-negative effect of variants in the critical TK domains in severe cases. We also share the experience of prenatal diagnosis and informed reproductive choices for the affected families.

Genetic subtypes and phenotypic characteristics of 110 patients with Prader-Willi syndrome.

BACKGROUND: Prader-Willi syndrome (PWS) is a complex disorder caused by impaired paternally expressed genes on chromosome 15q11-q13. Variable findings have been reported about the phenotypic differences among PWS genetic subtypes. METHODS: A total of 110 PWS patients were diagnosed from 8,572 pediatric patients included from July 2013 to December 2021 by MLPA and MS-MLPA assays. Atypical deletions were defined by genomic CNV-sequencing. Maternal uniparental disomy (UPD) was subgrouped by microsatellite genotyping. Clinical data were collected for phenotype-genotype associations. Twenty-one patients received growth hormone (GH) treatment, and the anthropometric and laboratory parameters were evaluated and compared. RESULTS: Genetically, the 110 patients with PWS included 29 type I deletion, 56 type II deletion, 6 atypical deletion, 11 heterodisomy UPD, and 8 isodisomy UPD. The UPD group had significantly higher maternal age (31.4 ± 3.4 vs 27.8 ± 3.8 years), more anxiety (64.29% vs 26.09%) and autistic traits (57.14% vs 26.09%), and less hypopigmentation (42.11% vs 68.24%) and skin picking (42.86% vs 71.01%) than the deletion group. The type I deletion group was diagnosed at earlier age (3.7 ± 3.3 vs 6.2 ± 3.2 years) and more common in speech delay (95.45% vs 63.83%) than the type II. The isodisomy UPD group showed a higher tendency of anxiety (83.33% vs 50%) than the heterodisomy. GH treatment for 1 year significantly improved the SDS of height (- 0.43 ± 0.68 vs - 1.32 ± 1.19) and IGF-I (- 0.45 ± 0.48 vs - 1.97 ± 1.12). No significant changes were found in thyroid function or glucose/lipid metabolism. CONCLUSION: We explored the physical, psychological and behavioral phenotype-genotype associations as well as the GH treatment effect on PWS from a large cohort of Chinese pediatric patients. Our data might promote pediatricians' recognition and early diagnosis of PWS.

Microscopic Oil Displacement Mechanism of CO2 in Low-Permeability Heterogeneous Glutenite Reservoirs in the Junggar Basin.

Carbon dioxide (CO2) flooding is a promising method for developing low-permeability heterogeneous glutenite reservoirs (LPHGRs) featured with low natural energy. Herein, the focus of this work was to study the microscopic oil displacement mechanism of CO2 in LPHGRs. First, the micropore structure and mineral composition of LPHGRs were analyzed, and the effect of CO2 on low-permeability reservoirs was then studied. Also, the mechanism of CO2 displacement in low-permeability reservoirs on a pore scale was analyzed using nuclear magnetic resonance technology in different dimensions. The experimental results showed that the mineral composition of the rock mainly included quartz, feldspar, and clay minerals. The core pores were poorly developed and highly heterogeneous. The clay and other mineral particles produced by the dissolution reaction of rocks and minerals migrated and deposited with formation fluid to damage the reservoir. On the contrary, it also improved the pore structure, increased pore space, and increased reservoir permeability. The miscible interaction between CO2 and crude oil formed a stable displacement front, which enabled crude oil to be well displaced from the macropores and medium pores. However, this interaction generated negligible effects on the small pores. The experimental results provided important indicators for CO2 development in LPHGRs.

Identification and Functional Characterization of Antifreeze Protein and Its Mutants in Dendroctonus armandi (Coleoptera: Curculionidae: Scolytinae) Larvae Under Cold Stress.

Dendroctonus armandi (Tsai and Li) (Coleoptera: Curculionidae: Scolytinae) is considered to be the most destructive forest pest in the Qinling and Bashan Mountains of China. Low winter temperatures limit insect's populations, distribution, activity, and development. Insects have developed different strategies such as freeze-tolerance and freeze-avoidance to survive in low temperature conditions. In the present study, we used gene cloning, real-time polymerase chain reaction (PCR), RNA interference (RNAi), and heterologous expression to study the function of the D. armandi antifreeze protein gene (DaAFP). We cloned the 800 bp full-length cDNA encoding 228 amino acids of DaAFP and analyzed its structure using bioinformatics analysis. The DaAFP amino acid sequence exhibited 24-86% similarity with other insect species. The expression of DaAFP was high in January and in the larvae, head, and midgut of D. armandi. In addition, the expression of DaAFP increased with decreasing temperature and increasing exposure time. RNAi analysis also demonstrated that AFP plays an important role in the cold tolerance of overwintering larvae. The thermal hysteresis and antifreeze activity assay of DaAFP and its mutants indicated that the more regular the DaAFP threonine-cystine-threonine (TXT) motif, the stronger the antifreeze activity. These results suggest that DaAFP plays an essential role as a biological cryoprotectant in overwintering D. armandi larvae and provides a theoretical basis for new pest control methods.

Molecular and phenotypic characteristics of 15q24 microdeletion in pediatric patients with developmental disorders.

Chromosome 15q24 microdeletion is a rare genetic disorder characterized by development delay, facial dysmorphism, congenital malformations, and occasional autism spectrum disorder (ASD). In this study, we identified five cases of 15q24 microdeletion using multiplex ligation-dependent probe amplification (MLPA) technology in a cohort of patients with developmental delay and/or intellectual disability. Two of these five cases had deletions that overlapped with the previously defined 1.1 Mb region observed in most reported cases. Two cases had smaller deletions (< 0.57 Mb) in the 15q24.1 low copy repeat (LCR) B-C region. They presented significant neurobehavioral features, suggesting that this smaller interval is critical for core phenotypes of 15q24 microdeletion syndrome. One case had minimal homozygous deletion of less than 0.11 Mb in the 15q24.1 LCR B-C region, which contained CYP1A1 (cytochrome P450 family 1 subfamily A member 1) and EDC3 (enhancer of mRNA decapping 3) genes, resulting in poor immunity, severe laryngeal stridor, and lower limbs swelling. This study provides additional evidence of 15q24 microdeletion syndrome with genetic and clinical findings. The results will be of significance to pediatricians in their daily practice.

Expression Levels of Detoxification Enzyme Genes from Dendroctonus armandi (Coleoptera: Curculionidae) Fed on a Solid Diet Containing Pine Phloem and Terpenoids.

Bark beetles overcome the toxic terpenoids produced by pine trees by both detoxifying and converting them into a pheromone system. Detoxification enzymes such as cytochrome P450s, glutathione S-transferases, and carboxylesterases are involved in the ability of Dendroctonus armandi to adapt to its chemical environment. Ten genes from these three major classes of detoxification enzymes were selected to study how these enzymes help D. armandi to respond to the host defenses. The expression profile of these detoxification enzyme genes was observed in adult beetles after feeding on different types of diet. Significant differences were observed between two types of seminatural diet containing the phloem of pines, and a purely artificial diet containing five monoterpenes ((-)-α-pinene, (-)-ß-pinene, (+)-3-carene, (±)-limonene, and turpentine oil) also caused differential transcript levels in the detoxification enzyme genes. The results suggest that monoterpenes enter the beetles through different routes (i.e., respiratory and digestive systems) and cause the expression of different genes in response, which might be involved in pheromone metabolism. In addition, the xenobiotic metabolism in bark beetles should be considered as a system comprising multiple detoxifying enzymes.

Experimental Study on Supercritical CO2 Huff and Puff in Tight Conglomerate Reservoirs.

A tight conglomerate reservoir is a kind of unconventional reservoir with strong heterogeneity, and CO2 injection is an economical and environmentally friendly method to enhance tight oil recovery. Supercritical CO2 is a very promising fluid medium for unconventional reservoir development due to its gas-liquid dual properties. In this study, the production effects of supercritical CO2 and non-supercritical CO2 in tight conglomerate reservoirs were quantitatively analyzed by huff and puff simulation experiments conducted under reservoir conditions (formation pressure 37 MPa, temperature 89 °C). Also, the influencing factors of CO2 huff and puff production, including injection volume, soaking time, and throughput cycles, were investigated. The results showed that supercritical CO2 improves the recovery by 4.02% compared with non-supercritical CO2. It could be seen that supercritical CO2 plays a positive role in improving tight conglomerate reservoirs. The optimal injection volume, soaking time, and throughput cycles were determined to be 0.50 PV, 2 h, and 3 cycles, respectively. This paper provides an important basis for the study of supercritical CO2 production in tight conglomerate reservoirs.

Copy number variations of chromosome 17p11.2 region in children with development delay and in fetuses with abnormal imaging findings.

BACKGROUND: Deletion and duplication of the 3.7 Mb region in 17p11.2 result in two syndromes, Smith-Magenis syndrome and Potocki-Lupski syndrome, which are well-known development disorders. The purpose of this study was to determine the prevalence, genetic characteristics and clinical phenotypes of 17p11.2 deletion/duplication in Chinese children with development delay and in fetuses with potential congenital defects. METHODS: 7077 children with development delay and/or intellectual disability were screened by multiplex ligation-dependent probe amplification P245 assay. 7319 fetuses with potential congenital defects were tested using next generation sequencing technique. RESULTS: 417 of 7077 pediatric patients were determined to carry chromosome imbalance. 28 (28/7077, 0.4%) cases had imbalance at chromosome 17p11.2. Among them, 12 cases (42.9%) had heterozygous deletions and 16 cases (57.1%) had heterozygous duplications. The clinical phenotypes were variable, including neurobehavioral disorders, craniofacial/skeletal anomalies, immunologic defects, ocular problems and organ malformations. 263 of 7319 fetuses were recognized to have genomic copy number variations. Only 2 of them were found to harbor 17p11.2 imbalance. The fetus with deletion presented with ventricular septal defect and the fetus with duplication had cerebral ventricle dilation. CONCLUSION: Our study highlights the phenotypic variability associated with 17p11.2 variations in China. The results further expand the phenotypic spectrum of SMS/PTLS and increase awareness of these disruptive mutations among clinicians.

[Effectiveness of proximal femoral nail anti-rotation and cerclage fixation for complicated femoral subtrochanteric fractures].

OBJECTIVE: To investigate the effectiveness of proximal femoral nail anti-rotation (PFNA) and cerclage fixation for complicated femoral subtrochanteric fractures. METHODS: A clinical data of 74 patients with complicated femoral subtrochanteric fractures, who were admitted between March 2016 and March 2019 and met the criteria, was retrospectively analyzed. Among them, 39 patients were treated with limited open reduction and PFNA combined with cerclage fixation (observation group) and 35 patients were treated with closed reduction and PFNA fixation (control group). There was no significant difference in gender, age, cause of injury, side and type of fracture, and the time from injury to operation ( P>0.05). The ratio of postoperative hemoglobin (1, 3, and 5 days) to the preoperative hemoglobin, the operation time, the first weight-bearing time after operation, and the hospital stay were recorded. X-ray films were taken to observe fracture healing in the two groups and bone resorption around the cerclage in the observation group, and the fracture healing time was recorded. Hip function was evaluated by Harris scoring. RESULTS: The operation time of the observation group was significantly longer than that of the control group ( P<0.05), but the first weight-bearing time and hospital stay were significantly shorter ( P<0.05). All patients were followed up 12 months. There was no significant difference in the ratios of post- to pre-operative hemoglobin (1, 3, and 5 days) between the two groups ( P>0.05). X-ray film reexamination showed that the fractures of the two groups healed smoothly, and the fracture healing time of the observation group was significantly shorter than that of the control group ( t=-12.989, P=0.000). No bone resorption around the cerclage occurred in the observation group. The Harris scores of the observation group were better than those of the control group at 7 days and 1, 2, and 3 months after operation ( P<0.05), and there was no significant difference between the two groups at 6 months after operation ( t=1.329, P=0.180). CONCLUSION: Compared with PFNA fixation, PFNA combined with cerclage fixation for the complicated femoral subtrochanteric fractures has a shorter operation time, and can obtain immediate stability after fixation, which can meet the needs of patients for early functional exercise.

Cloning and Expression of the Neuropeptide F and Neuropeptide F Receptor Genes and Their Regulation of Food Intake in the Chinese White Pine Beetle Dendroctonus armandi.

Neuropeptide F (NPF) is an important signaling molecule that acts as a neuromodulator to regulate a diversity of physiological and behavioral processes from vertebrates to invertebrates by interaction with NPF receptors, which are G protein-coupled receptors (GPCR). However, nothing is known about NPF in Chinese white pine beetle, Dendroctonus armandi, a destructive pest of natural and coniferous forests in the middle Qinling Mountains of China. We have cloned and characterized cDNAs encoding one NPF precursor and two NPF receptors in D. armandi and made bioinformatics predictions according to the deduced amino acid sequences. They were highly similar to that of Dendroctonus ponderosa. The transcription levels of these genes were different between larvae and adults of sexes, and there were significant differences among the different developmental stages and tissues and between beetles under starvation and following re-feeding states. Additionally, downregulation of NPF and NPFR by injecting dsRNA into beetles reduced their food intake, caused increases of mortality and decreases of body weight, and also resulted in a decrease of glycogen and free fatty acid and an increase of trehalose. These results indicate that the NPF signaling pathway plays a significant positive role in the regulation of food intake and provides a potential target for the sustainable management of this pest.

Identifying of 22q11.2 variations in Chinese patients with development delay.

BACKGROUND: 22q11.2 variation is a significant genetic factor relating to development delay and/or intellectual disability. However, the prevalence, genetic characteristics and clinical phenotype in Chinese patients are unknown. METHODS: In total 6034 patients with development delay and/or intellectual disability were screened by multiplex ligation-dependent probe amplification (MLPA) P245 and G-band karyotyping. The positive patients with 22q11.2 imbalance were confirmed by MLPA P250 assay. RESULTS: 52 (0.86%) patients were found to carry different levels of 22q11.2 variations, in which 37 cases (71.2%) had heterozygous deletions, whereas 15 (28.8%) had heterogeneous duplications. 34 cases (65.4%) carried typical imbalance from low copy repeat (LCR) 22 A to D. The other cases had atypical variations, relating to LCR22 A-B, LCR22 C-D, LCR22 B-D, LCR22 D-E, LCR22 E-F and LCR22 B-F region. The phenotypes of these 52 patients were variable, including development delay, language delay, facial anomalies, heart defects, psychiatric/behavior problems, epilepsy, periventricular leukomalacia, hearing impairment, growth delay etc. CONCLUSION: These data revealed the prevalence and variability of 22q11.2 genomic imbalance in Chinese patients with development delay and/or intellectual disability. It suggested that genetic detection of 22q11.2 is necessary, especially for the patients with mental retardation and development disorders, which deserves the attention of all pediatricians in their daily work.

Isolation and expression of five genes in the mevalonate pathway of the Chinese white pine beetle, Dendroctonus armandi (Curculionidae: Scolytinae).

The Chinese white pine beetle Dendroctonus armandi (Tsai and Li) is a significant pest of the Qinling and Bashan Mountains pine forests of China. The Chinese white pine beetle can overcome the defences of Chinese white pine Pinus armandi (Franch) through pheromone-assisted aggregation that results in a mass attack of host trees. We isolated five full-length complementary DNAs encoding mevalonate pathway-related enzyme genes from the Chinese white pine beetle (D. armandi), which are acetoacetyl-CoA thiolase (AACT), geranylgeranyl diphosphate synthase (GGPPS), mevalonate kinase (MK), mevalonate diphosphate decarboxylase (MPDC), and phosphomevalonate kinase (PMK). Bioinformatic analyses were performed on the full-length deduced amino acid sequences. Differential expression of these five genes was observed between sexes, and within these significant differences among topically applied juvenile hormone III (JH III), fed on phloem of P. armandi, tissue distribution, and development stage. Mevalonate pathway genes expression were induced by JH III and feeding.

Isolation, Expression Profiling, and Regulation via Host Allelochemicals of 16 Glutathione S-Transferases in the Chinese White Pine Beetle, Dendroctonus armandi.

The Chinese white pine beetle (Dendroctonus armandi) is undoubtedly one of the most important pests causing ecological damage in the Qinling Mountains. When bark beetles invade conifers, they must overcome host tree defenses, including primary resistance and induced resistance responses. Moreover, this induced resistance occurs following herbivory by bark beetles. Bark beetles have a corresponding defense mechanism for degrading toxic compounds, and glutathione S-transferases (GSTs) can catalyze the binding of endogenous substances that reduce glutathione (GSH) to various harmful electrophilic substrates, increasing their solubility and facilitating their excretion from cells. In this experiment, we successfully obtained sixteen full-length sequences of D. armandi, which belonged to four GST categories (delta, epsilon, sigma, and theta). The transcript levels of sixteen GSTs in D. armandi were compared at four developmental stages (larvae, pupae, teneral adults, and adults), three different tissues (antennae, gut, and reproductive organs), and under various levels of terpenoid stimuli during feeding on phloem tissue to evaluate the various relevant modes of action. This study aids in the understanding of the interaction between monoterpenes and beetles, and beetles' detoxification through GSTs.

Fabrication of protease XIV-loaded microspheres for cell spreading in silk fibroin hydrogels.

Due to their excellent mechanical strength and biocompatibility, silk fibroin(SF) hydrogels can serve as ideal scaffolds. However, their slow rate of natural degradation limits the space available for cell proliferation, which hinders their application. In this study, litchi-like calcium carbonate@hydroxyapatite (CaCO3@HA) porous microspheres loaded with proteases from Streptomyces griseus (XIV) were used as drug carriers to regulate the biodegradation rate of SF hydrogels. The results showed that litchi-like CaCO3@HA microspheres with different phase compositions could be prepared by changing the hydrothermal reaction time. The CaCO3@HA microspheres controlled the release of Ca ions, which was beneficial for the osteogenic differentiation of mesenchymal stem cells (MSCs). The adsorption and release of protease XIV from the CaCO3@HA microcarriers indicated that the loading and release amount can be controlled with the initial drug concentration. The weight loss test and SEM observation showed that the degradation of the fibroin hydrogel could be controlled by altering the amount of protease XIV-loaded CaCO3@HA microspheres. A three-dimensional (3D) cell encapsulation experiment proved that incorporation of the SF hydrogel with protease XIV-loaded microspheres promoted cell dispersal and spreading, suggesting that the controlled release of protease XIV can regulate hydrogel degradation. SF hydrogels incorporated with protease XIV-loaded microspheres are suitable for cell growth and proliferation and are expected to serve as excellent bone tissue engineering scaffolds.

[Experimental study on autologous injectable platelets rich fibrin combined with bone mesenchymal stem cells in treating sciatic nerve injury in rats].

OBJECTIVE: To investigate the effectiveness of autologous injectable platelet rich fibrin (i-PRF) combined with bone marrow mesenchymal stem cells (BMSCs) for sciatic nerve injury in rats. METHODS: BMSCs were isolated and cultured from tibial bone marrow of Sprague Dawley (SD) neonatal rats aged 10-15 days and passaged to the 4th generation. i-PRF was prepared from posterior orbital venous blood of adult SD rats by improved low-speed centrifugation. Twenty-four adult SD rats were selected and randomly divided into 4 groups with 6 rats in each group after the sciatic nerve Ⅲ degree injury model was established by modified crush injury method. Groups A, B, C, and D were injected with BMSCs suspension+autologous i-PRF, autologous i-PRF, BMSCs suspension, and normal saline, respectively. The Basso-Beattie-Bresnahan (BBB) score was used to evaluate the recovery of neurological function of the affected limb of rats every week from 1 to 8 weeks after operation. At 2 months after operation, the rats were sacrificed and the histological changes of sciatic nerve were observed by HE staining. The microstructural changes of nerve fibers, myelin sheath, and nucleus were observed by transmission electron microscope. The expressions of N-cadherin, Nestin, and glial fibrillary acidic protein (GFAP) were detected by Western blot. RESULTS: No immune rejection or death occurred in the rats after operation. There was no significant difference in BBB scores between groups at 1 week after operation ( P>0.05); at 2-8 weeks after operation, BBB scores in group A were significantly higher than those in groups B, C, and D, and in groups B, C than in group D ( P<0.05), there was no significant difference between groups B and C ( P>0.05). HE staining showed that the nerve fibers in group A arranged in order, without defect or demyelination; the nerve fibers in group B were not clear and slightly swollen; some of the nerve fibers in group C were disordered and demyelinated; the nerve fibers in group D were not continuous, obviously demyelinated, and some of the nerve adventitia damaged. Transmission electron microscope showed that the structure of nerve fibers in group A was clear, myelin sheath was complete, and nucleus was dense; group B was slightly less than group A; group C had fuzzy structure, demyelination, and hollowing out; group D had disorder structure, demyelination, and hollowing out, and the middle part of nerve adventitia continuity. Western blot detection results showed that there was no significant difference in the relative expression of Nestin between groups ( P>0.05). The relative expression of N-cadherin was significantly lower in groups B, C, and D than in group A, in groups C and D than in group B, and in group D than in group C ( P<0.05). The relative expression of GFAP was significantly lower in groups B, C, and D than in group A, in group D than in groups B and C ( P<0.05); there was no significant difference between groups B and C ( P>0.05). CONCLUSION: Autologous i-PRF combined with BMSCs can effectively treat sciatic nerve tissue injury in rats.

Nonsense suppression induced readthrough of a novel PAX6 mutation in patient-derived cells of congenital aniridia.

BACKGROUND: Congenital aniridia is a severe ocular abnormality characterized by incomplete formation of the iris and many other ocular complications. Most cases are caused by the paired box 6 (PAX6) gene mutations generating premature termination codons (PTCs). METHODS: Ophthalmic examination was performed on a Chinese pedigree with congenital aniridia. The mutation was identified by targeted next-generation sequencing. Nonsense suppression therapy was applied on patient-derived lymphocytes. The PAX6 expression was assayed by real-time polymerase chain reaction and Western blot. RESULTS: Complete aniridia was complicated with horizontal nystagmus, contract, foveal hypoplasia, and microphthalmia. A novel heterozygous c.702_703delinsAT (p.Tyr234*) mutation was found in exon 9 of PAX6, generating a PTC at the homeodomain. There were about 50% reductions of both full-length PAX6 protein and PAX6 mRNA in patient-derived lymphocytes, indicating haploinsufficiency due to nonsense-mediated mRNA decay. Ataluren (PTC124) and geneticin (G418) could induce about 30%-40% translational readthrough. Nonsense suppression therapy restored PAX6 protein to about 65%-70% of unaffected family controls. CONCLUSION: Our data expanded the genetic and phenotypic variations of congenital aniridia, and showed the therapeutic effect of nonsense suppression on this disease using patient-derived cells.

Research Progress on the Molecular Mechanism by Which Depression Affects Bone Metabolism.

Increasing evidence indicates that depression affects bone metabolism to some extent, but the specific mechanisms are still unclear. Numerous studies have confirmed that a variety of signaling molecules are involved in depression's impact on fracture healing, including serum monoamine neurotransmitters, cytokines, inflammatory markers, growth factors, and metabolites. This article comprehensively discusses the effects of depression-associated signaling molecules on bone metabolism and their underlying mechanisms to provide a basis for early preventive intervention for delayed fracture healing in patients with depression.

Identification, Expression Patterns and RNA Interference of Aquaporins in Dendroctonus armandi (Coleoptera: Scolytinae) Larvae During Overwintering.

The ability to survive annual temperature minima could be a key determinant of distribution limits for insects under global climate change. Recent studies have suggested that insect aquaporins are indispensable for cellular water management under conditions that lead to dehydration and cold stress. Aquaporins are integral membrane water channel proteins in the major intrinsic protein superfamily and promote selected solutes and the movement of water across biological membranes. We cloned and characterized nine full-length aquaporins from Dendroctonus armandi (DaAqps), the most destructive forest pest in the Qinling Mountains of Shaanxi Province, China. Eight of the DaAqps belong to three classical aquaporin grades, including the Drosophila integral protein, the Pyrocoelia rufa integral protein, the entomoglyceroporins and one that belongs to the unorthodox grade of aquaporin 12-like channels. The DaAqps were increasingly expressed during different developmental stages and in different larval tissues, and expression peaked in mid-winter. They were tested under cold conditions for different lengths of time, and the expression of almost all DaAqps was down regulated with decreasing temperatures and long-term exposure to cold conditions. However, when the lowest temperatures were reached, the levels were immediately upregulated. These genes indicate that cold tolerance can improve through mortality responses at low temperatures after RNA interference of DaAqps. In our study, we analyzed the molecular response, expression patterns, and RNA interference of DaAqps and clarified the crucial role of protective compounds (aquaporins) underlying D. armandi cold tolerance and provide a new pest control method.

Isolation of CarE genes from the Chinese white pine beetle Dendroctonus armandi (Curculionidae: Scolytinae) and their response to host chemical defense.

BACKGROUND: Bark beetles rely on detoxifying enzymes to resist the defensive terpenoids of their host trees. Research on carboxylesterases (CarEs) has focused on their multiple functions in the metabolic detoxification of pesticides and plant allelochemicals, drug resistance, and juvenile hormone and pheromone degradation. RESULT: We identified eight new CarE genes in the Chinese white pine beetle (Dendroctonus armandi) and carried out bioinformatics analysis on the deduced full-length amino acid sequences. Differential transcript levels of CarE genes were observed between sexes; within these levels, significant differences were found among the different development stages, and between insects fed on the phloem of Pinus armandi and exposed to five stimuli [(-)-α-pinene, (-)-ß-pinene, (+)-3-carene, limonene and turpentine] at 8 and 24 h. CONCLUSION: Transcription levels of CarE genes suggest some relationship with the detoxification of terpenoids released by host trees. The functions of bark beetle esterase are mainly in hydrolyzing the host chemical defense and degrading odorant molecules during host selection and colonization. © 2018 Society of Chemical Industry.

Differences in IGF axis-related proteins in amniotic fluid of trisomy 21 and trisomy 18 using a multiple reaction monitoring approach.

OBJECTIVE: Trisomy 21 and trisomy 18 are the two most common chromosomal anomalies in live births. To find new biomarkers for aneuploidies and pathogenesis of fetal malformations, we measured insulin-like growth factor (IGF) axis-related proteins in amniotic fluid (AF) of pregnant women carrying trisomies 21 or 18 affected fetuses using multiple reaction monitoring (MRM) approach. METHOD: Eighty-five AF samples from pregnant women carrying either trisomy 21, trisomy 18, or normal fetuses were collected. IGF axis-related proteins in AF after serial treatments were quantitated with MRM method. The differential protein levels were also confirmed by western blot in AF without any treatment. RESULTS: The IGF type I receptor and pregnancy-associated plasma protein-A in AF of trisomy 21 (1.35 ± 0.32 and 13.36 ± 3.64 µg/mg protein) and trisomy 18 (1.39 ± 0.40 and 12.80 ± 1.84 µg/mg protein) were decreased versus normal controls (2.16 ± 0.59 and 23.77 ± 6.18 µg/mg protein). IGF binding protein 5 was reduced in trisomy 18 (1.47 ± 0.33 vs 2.36 ± 0.77 µg/mg protein). These alterations were confirmed by western blot. The other proteins showed no significant difference between the three groups. CONCLUSION: Our data suggested that MRM can provide a powerful platform for the identification of biomarkers in AF that have crucial developmental effects in the aneuploid fetus.