[Characteristics of electromyography in 111 patients with generalized myasthenia gravis: a retrospective study]

Objective: To retrospectively analyze the characteristics of the electromyography (EMG) study in generalized myasthenia gravis (gMG) patients. Methods: A total of 111 gMG patients were enrolled. Patients were divided into two groups: 36 severe patients discontinuing pyridostigmine bromide (PB) for 8 hours were included in 8 h group, and 75 g MG patients discontinuing PB for at least 18 hours were included in>18 h group. The clinical information and EMG study data were collected and analyzed. Results: There were statistically significant differences in the initial location of the myasthenia muscle (P=0.027), the affected muscle detected by the EMG (P=0.015) and quantitative myasthenia gravis (QMG) score (P<0.01) between the two groups. Comparisons in each group revealed that the highest positive rate of low-frequency repetitive nerve stimulation (RNS) of facial in 8 h group and>18 h group was 94.4% and 60.0%, respectively. Comparisons between the two groups showed that the positive rate of low-frequency RNS in 8 h group was significantly higher than that in>18 h group (94.4% vs 70.7%, χ(2)=8.115, P=0.004). In particular, the positive rate of RNS in facial nerves and the extent of the amplitude decrease under different electrical stimulations (1 Hz, 3 Hz, and 5 Hz) were dramatically higher in the 8 h group (P<0.01). Conclusions: For gMG patients, the facial and accessory nerve detection can improve the positive rate of RNS. Different muscles had various sensitivity to PB, and orbicularis oculi muscle seemed the least sensitive muscle to PB. For suspect MG patients in severe condition, only discontinuing PB medication for 8 h before low-frequency RNS testing can avoid the deterioration and also obtain similar positive rate.

[Expression of gamma-aminobutyric acid type A receptor beta3 subunit in murine cleft palate induced by 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin]

Objective: To investigate the expression of gamma-aminobutyric acid type A receptor beta3 subunit (GABRB3) on cleft palate in C57BL/6J mice induced by 2,3,7,8-tetrachlorodibenzo- p-dioxin (TCDD). Methods: Sixty C57BL/6J pregnant mice on gestation day (GD) 10.5 were divided into two groups: one group was administered through gastric tubes one dose of 28 μg/kg TCDD (experimental group) and the other group was administered through gastric tubes one dose of 5.6 ml/kg corn oil (control group). Embryos were removed by cesarean section from pregnant mice during the palatal formation stage (GD 13.5-17.5) and the palatal tissue studied in morphological and histological observation. The relative mRNA and protein expression of GABRB3 was measured by real-time quantitative PCR and Western blotting. Localization of GABRB3 protein was measured by immunohistochemistry or immunofluorescence. Results: The incidence of cleft palate at GD17.5 was 100% in experimental group and there was no cleft palate occurred in the control group (0); elevation of palatine processes in experimental group was completed on GD15.5 which was clearly delayed by a day compared with that in control group. On GD14.5-GD17.5, the mRNA expression (0.561±0.073, 0.728±0.104, 0.782±0.137, 0.686±0.145) and protein expression (0.288±0.013, 0.404±0.017, 0.399±0.012, 0.307±0.010) in the experimental group were significantly lower than the control group mRNA expression (0.818±0.088, 0.865±0.086, 1.021±0.054, 1.163±0.179) and protein expression (0.481±0.017, 0.456±0.009, 0.474±0.016, 0.529±0.015)(P<0.05). Immunohistochemistry and immunofluorescence showed that GABRB3 was mainly expressed in the mesenchymal cells and medial edge epithelium. Conclusions: TCDD delayed palatal shelf elevation and eventually led to cleft palate may be associated with a decrease in GABRB3. GABRB3 may play an important role in the elevation and fusion phases of the palate development.

The midgut V-ATPase subunit A gene is associated with toxicity to crystal 2Aa and crystal 1Ca-expressing transgenic rice in Chilo suppressalis

Insecticidal crystal (Cry) proteins produced by the bacterium Bacillus thuringiensis (Bt) are toxic to a diverse range of insects. Transgenic rice expressing Cry1A, Cry2A and Cry1C toxins have been developed that are lethal to Chilo suppressalis, a devastating insect pest of rice in China. Identifying the mechanisms underlying the interactions of Cry toxins with susceptible hosts will improve both our understanding of Cry protein toxicology and long-term efficacy of Bt crops. In this study, we tested the hypothesis that V-ATPase subunit A contributes to the action of Cry1Ab/1Ac, Cry2Aa and Cry1Ca toxins in C. suppressalis. The full-length V-ATPase subunit A transcript was initially cloned from the C. suppressalis larval midgut and then used to generate double-stranded RNA (dsRNA)-producing bacteria. Toxicity assays using transgenic rice lines TT51 (Cry1Ab and Cry1Ac fusion genes), T2A-1 (Cry2Aa), and T1C-19 (Cry1Ca) in conjunction with V-ATPase subunit A dsRNA-treated C. suppressalis larvae revealed significantly reduced larval susceptibility to T2A-1 and T1C-19 transgenic rice, but not to TT51 rice. These results suggest that the V-ATPase subunit A plays a crucial role in mediating Cry2Aa and Cry1Ca toxicity in C. suppressalis. These findings will have significant implications on the development of future resistance management tools.

Fabrication and Properties of a Bio-Based Biodegradable Thermoplastic Polyurethane Elastomer

Using the melt polycondensation of five bio-based aliphatic monomers (succinic acid, sebacic acid, fumaric acid, 1,3-propanediol, and 1,4-butanediol), we first synthesized the more flexible and biodegradable polyester diols (BPD) with an average molecular weight of 3825. Then, the BPD was polymerized with excessive 4,4'-diphenylmethane diisocyanate (MDI). Finally, the molecular chain extender of 1,4-butanediol (BDO) was used to fabricate the biodegradable thermoplastic polyurethane elastomer (BTPU), comprising the soft segment of BPD and the hard segment polymerized by MDI and BDO. Atomic force microscope (AFM) images showed the two-phase structure of the BTPU. The tensile strength of the BTPU containing 60% BPD was about 30 MPa and elongation at break of the BTPU was over 800%. Notably, the BTPU had superior biodegradability in lipase solution and the biodegradation weight loss ratio of the BTPU containing 80% BPD reached 36.7% within 14 days in the lipase solution.

[Effects of skin γδ T lymphocytes on wound healing of mice through regulating proliferation and differentiation of mice epidermal cells]

Objective: To explore effects of dendritic epidermal T cells (DETCs) and Vγ4 T lymphocytes on proliferation and differentiation of mice epidermal cells and the effects in wound healing of mice. Methods: (1) Six C57BL/6 male mice aged 8 weeks were collected and divided into control group and wound group according to random number table (the same grouping method below), with 3 mice in each group. A 4 cm long straight excision with full-thickness skin defect was cut on back of each mouse in wound group, while mice in control group received no treatment. On post injury day (PID) 3, mice in 2 groups were sacrificed, and skin within 5 mm from the wound margin on back of mice in wound group and normal skin on corresponding part of mice in control group were collected to make single cell suspensions. The percentage of Vγ4 T lymphocyte expressing interleukin-17A (IL-17A) and percentage of DETCs expressing insulin-like growth factor Ⅰ (IGF-Ⅰ) were detected by flow cytometer. (2) Ten C57BL/6 male mice aged 8 weeks were collected and divided into control group and Vγ4 T lymphocyte depletion group with 5 mice in each group. Mice in Vγ4 T lymphocyte depletion group were injected with 200 g Vγ4 T lymphocyte monoclonal neutralizing antibody of Armenian hamster anti-mouse intraperitoneally, and mice in control group were injected with the same amount of Armenian hamster Ig intraperitoneally. One hole with full-thickness skin defect was made on each side of spine of back of each mice. The wound healing was observed on PID 1-8, and percentage of remaining wound area was calculated. (3) Six C57BL/6 male mice aged 8 weeks were grouped and treated in the same way as in experiment (2), with 3 mice in each group. On PID 3, expressions of IL-17A and IGF-Ⅰ in epidermis on margin of wound were detected with Western blotting. (4) Thirty C57BL/6 male mice aged 3 days were sacrificed, and epidermal cells were extracted. The keratin 14 positive cell rate was examined by flow cytometer (the same detecting method below). (5) Another batch of mouse epidermal cells were collected and divided into control group, IGF-Ⅰ group, and IL-17A group, with 3 wells in each group (the same well number below). Cells in IGF-Ⅰ group and IL-17A group were added with 1 mL recombinant mouse IGF-Ⅰ and IL-17A with final mass concentration of 100 ng/mL respectively, while cells in control group were added with the same amount of sterile phosphate buffered saline (PBS). On post culture day (PCD) 5, keratin 14 negative cell rate was examined. Another batch of mouse epidermal cells were collected, grouped, and treated in the same way as aforementioned experiment, and keratin 10 positive cell rate was examined on PCD 10. (6) Another batch of mouse epidermal cells were collected and added with 4 mmol/L 5(6)-carboxyfluorescein diacetate N-succinimidyl ester (CFSE) solution, and divided into control 0 d group, control 7 d group, IGF-Ⅰ group, and IL-17A group. Cells in IGF-Ⅰ group and IL-17A group were treated in the same way as the corresponding groups in experiment (5), and cells in control 0 d group and control 7 d group were treated in the same way as the control group in experiment (5). The CFSE fluorescence peaks were examined on PCD 0 of control 0 d group and PCD 7 of the other 3 groups. (7) Another batch of mouse epidermal cells were collected and divided into control group and IGF-Ⅰ group. Cells in IGF-Ⅰ group were added with 1 mL recombinant mouse IGF-Ⅰ with final mass concentration of 100 ng/mL, and cells in control group were added with the same amount of sterile PBS. On PCD 5, cells were underwent keratin 14 staining and CFSE staining as aforementioned, and keratin 14 negative cell rate of CFSE positive cells was examined. Another batch of mouse epidermal cells were collected and divided into control group and IL-17A group. Cells in IL-17A group were added with 1 mL recombinant mouse IL-17A with final mass concentration of 100 ng/mL, and cells in control group were added with the same amount of sterile PBS. On PCD 5, keratin 14 negative cell rate of CFSE positive cells was examined. Data were processed with one-way analysis of variance and t test. Results: (1) On PID 3, percentage of DETC expressing IGF-Ⅰ in normal epidermis of control group was (9.9±0.8)%, significantly lower than (19.0±0.6)% of epidermis around margin of wound group (t=8.70, P<0.01); percentage of Vγ4 T lymphocyte expressing IL-17A in normal epidermis of control group was (0.123±0.024)%, significantly lower than (8.967±0.406)% of epidermis around margin of wound group (t=21.77, P<0.01). (2) On PID 1-4, there was obvious inflammatory reaction around wounds of mice in control group, and on PID 5-8, the wound area was still large. On PID 1-4, there was slight inflammatory reaction around wounds of mice in Vγ4 T lymphocyte depletion group, and on PID 5-8, the wound area was significantly reduced. On PID 3-7, percentages of residual wound area in Vγ4 T lymphocyte depletion group were significantly lower than those in control group (t=5.92, 5.74, 7.17, 5.38, 5.57, P<0.01), while percentages of residual wound area in two groups on PID 1, 2, 6 were similar (t=1.46, 3.17, 3.10, P>0.05). (3) On PID 3, compared with those in control group, expression of IL-17A and IGF-Ⅰ in epidermis around wound margin of mice in Vγ4 T lymphocyte depletion group was markedly decreased and increased respectively (t=8.47, 19.24, P<0.01). (4) The keratin 14 positive cell rate of mouse epidermal cells was 94.7%. (5) On PCD 5, the keratin 14 negative cell rate of mice in control group was markedly higher than that of IGF-Ⅰ group, while significantly lower than that of IL-17A group (t=7.25, 5.64, P<0.01). On PCD 10, the keratin 10 positive cell rate of mice in control group was significantly higher than that of IGF-Ⅰ group, while significantly lower than that of IL-17A group (t=3.99, 10.82, P<0.05 or P<0.01). (6) Compared with that of control 0 d group, CFSE fluorescence peaks of mouse epidermal cells in control 7 d group, IGF-Ⅰ group, and IL-17A group on PCD 7 shifted to the left. Compared with that of control 7 d group, CFSE fluorescence peaks of mouse epidermal cells in IGF-Ⅰ group and IL-17A group on PCD 7 shifted to the left. (7) On PCD 5, keratin 14 negative cell rate of CFSE positive cells of mice in control group was significantly higher than that in IGF-Ⅰ group (t=9.91, P<0.01), and keratin 14 negative cell rate of CFSE positive cells of mice in control group was markedly lower than that in IL-17A group (t=6.49, P<0.01). Conclusions: In the process of wound healing, IGF-Ⅰ secreted by DETC can promote the proliferation of mouse keratin 14 positive epidermal cells and inhibit their terminal differentiation, while IL-17A secreted by Vγ4 T lymphocyte can promote the proliferation and terminal differentiation of mouse keratin 14 positive epidermal cells, thus both IGF-Ⅰ and IL-17A can affect wound healing.

The efficacy of tranexamic acid for orthognathic surgery: a meta-analysis of randomized controlled trials

The efficacy of tranexamic acid in orthognathic surgery remains controversial. We conducted a systematic review and meta-analysis to explore the influence of tranexamic acid on blood loss for orthognathic surgery. We performed a search of PubMed, Embase, Web of science, EBSCO, and Cochrane library databases through October 2017 for randomized controlled trials (RCTs) assessing the effects of tranexamic acid versus placebo on orthognathic surgery. Meta-analysis was performed using the random-effects model. Six RCTs were included in the meta-analysis. Overall, compared with placebo in orthognathic surgery, tranexamic acid administration results in significantly decreased blood loss [mean difference (MD)=-159.73; 95% confidence interval (CI)=-236.42 to -83.03; P<0.0001], and higher postoperative haemoglobin (MD=0.71; 95% CI=0.11 to 1.31; P=0.02), but has no remarkable impact on postoperative haematocrit (MD=1.23; 95% CI=-1.22 to 3.69; P=0.33) and operation time (MD=-2.35; 95% CI=-18.05 to 13.36; P=0.77). In addition, patients with orthognathic surgery need decreased amounts of irrigant fluid (MD=-229.23; 95% CI=-399.63 to -58.83; P=0.008) after using tranexamic acid. We concluded that tranexamic acid promotes the bleeding control in orthognathic surgery.

[The investigation of the positive rate of intrinsic factor antibody and deficiency rate of vitamin B(12) in normal physical examination population]

Objective: To explore the positive rate of intrinsic factor antibody (IFAb) and level of vitamin B(12) (VitB(12)) in normal physical examination population and the possible relation between IFAb, VitB12 and sex, age, number of RBC, HGB and MCV. Methods: A total of 1 427 people who came to Peking Union Medical Colleague Hospital (PUMCH) for physical examination were enrolled. There were 758 males with average age of (52.5±14.5) years-old and 669 females with average age of (50.3±14.3) year-old. Beckman DxI800 automatic biochemical-immune analyzer and corollary reagents were used to analyze the level of serum IFAb and VitB(12). The results in different sex, age were documented and their correlation with the value of whole blood cell count was tested later on. Results: Among the 1 427 normal subjects, 66 (4.63%) were positive for IFAb. The positive rate for IFAb in the population≥40 years-old was higher than those<40 years-old (5.66% vs 1.48%, χ(2)=7.46, P=0.006). The deficiency rate of VitB(12) in the population<40 years-old, 40-59 years-old and ≥60 years-old was 2.22%, 2.51% and 5.50%, respectively (χ(2)=8.55, P=0.014). There were no difference between people with different sex in the positive rate of IFAb (5.15% for males and 4.04% for females, χ(2)=0.99, P=0.320) or in the deficiency rate of VitB(1)2 (3.83% for males and 2.69% for females, χ(2)=1.44, P=0.230). The results of multiple linear regression showed that HGB level of IFAb positive subjects was 3.05 g/L lower on average than those of IFAb negative, but IFAb had no effect on both RBC and MCV. There was no correlation between VitB(1)2 deficiency and HGB, RBC and MCV. Conclusion: The positive rate of IFAb and deficiency rate of VitB(1)2 increase as age increases. But the presence of VitB(12) deficiency is later than the positive findings of IFAb. IFAb showed some effects on the level of HGB, which may compensate the limitations of VitB(12) detection to some extent. It is necessary to check the IFAb and level of VitB(12) in people with middle or old ages.

Comparative Phosphoproteomic Profiling of Type III Adenylyl Cyclase Knockout and Control, Male, and Female Mice

Type III adenylyl cyclase (AC3, ADCY3) is predominantly enriched in neuronal primary cilia throughout the central nervous system (CNS). Genome-wide association studies in humans have associated ADCY3 with major depressive disorder and autistic spectrum disorder, both of which exhibit sexual dimorphism. To date, it is unclear how AC3 affects protein phosphorylation and signal networks in central neurons, and what causes the sexual dimorphism of autism. We employed a mass spectrometry (MS)-based phosphoproteomic approach to quantitatively profile differences in phosphorylation between inducible AC3 knockout (KO) and wild type (WT), male and female mice. In total, we identified 4,655 phosphopeptides from 1,756 proteins, among which 565 phosphopeptides from 322 proteins were repetitively detected in all samples. Over 46% phosphopeptides were identified in at least three out of eight biological replicas. Comparison of AC3 KO and WT datasets revealed that phosphopeptides with motifs matching proline-directed kinases' recognition sites had a lower abundance in the KO dataset than in WTs. We detected 14 phosphopeptides restricted to WT dataset (i.e., Rabl6, Spast and Ppp1r14a) and 35 exclusively in KOs (i.e., Sptan1, Arhgap20, Arhgap44, and Pde1b). Moreover, 95 phosphopeptides (out of 90 proteins) were identified only in female dataset and 26 only in males. Label-free MS spectrum quantification using Skyline further identified phosphopeptides that had higher abundance in each sample group. In total, 204 proteins had sex-biased phosphorylation and 167 of them had increased expression in females relative to males. Interestingly, among the 204 gender-biased phosphoproteins, 31% were found to be associated with autism, including Dlg1, Dlgap2, Syn1, Syngap1, Ctnna1, Ctnnd1, Ctnnd2, Pkp4, and Arvcf. Therefore, this study also provides the first phosphoproteomics evidence suggesting that gender-biased post-translational phosphorylation may be implicated in the sexual dimorphism of autism.

Polymersomes: Preparation and Characterization

Polymersomes, also called polymeric vesicles, are self-assembled by amphiphilic copolymers. Due to their unique characters, polymersomes are attracting more and more interest as an important class of vehicles for nanopharmaceuticals. In this chapter, various methods to prepare and characterize polymersomes are introduced systematically with several applicable examples. In addition, the advantages and disadvantages of each method were compared and analyzed with the aim to help readers choose the appropriate method in the process of experiments. Although some methods we introduced here are effective in preparing and characterizing polymersomes, the remaining challenge in this filed is to develop new tools. The reason is that polymersome is a kind of complex nanostructure, and some minor factors can affect the formation of polymersome. Meanwhile, more advanced technology should be developed to precisely determine the structure of some complex polymersomes such as multilayer polymersomes.

Long-term immunogenicity and immune persistence of live attenuated and inactivated hepatitis a vaccines: a report on additional observations from a phase IV study

Both live attenuated (HA-L) and inactivated (HA-I) hepatitis A vaccine were licensed for routine use in China. Although phase 1, 2 and 3 clinical studies of both vaccines have been completed, further systematic evaluation of their immunogenicity and immunological persistence under phase 4 clinical studies in a wide range of conditions and involving large populations is necessary. A phase IV clinical trial (NCT02601040) was performed in 9000 participants over 18 months of age. Geometric mean concentrations (GMCs) and seroconversion rates (SRs) were compared at five time points during 3 years for 1800 individuals among them. The SRs of HA-L and HA-I were 98.08% (95% CI 95.59%-99.38%) and 99.64% (95% CI 98.93%-100.00%) respectively 28 days after administration of the first dose, and remained at 97.07% (95% CI 94.31%-98.73%) or above and 96.73% (95% CI 94.07%-98.42%) or above respectively during the following 3 years. The GMCs for both the HA-L and HA-I groups showed that both vaccines elicited high anti-HAV titres, considerably more than the threshold of protection needed against HAV infection in humans, and these titres were sustained. Hence, both HA-I and HA-L vaccines could provide an excellent long-term protective effect, and supported the routine use of both vaccines.

Seamless Genetic Conversion of SMN2 to SMN1 via CRISPR/Cpf1 and Single-Stranded Oligodeoxynucleotides in Spinal Muscular Atrophy Patient-Specific Induced Pluripotent Stem Cells

Spinal muscular atrophy (SMA) is a kind of neuromuscular disease characterized by progressive motor neuron loss in the spinal cord. It is caused by mutations in the survival motor neuron 1 (SMN1) gene. SMN1 has a paralogous gene, survival motor neuron 2 (SMN2), in humans that is present in almost all SMA patients. The generation and genetic correction of SMA patient-specific induced pluripotent stem cells (iPSCs) is a viable, autologous therapeutic strategy for the disease. Here, c-Myc-free and non-integrating iPSCs were generated from the urine cells of an SMA patient using an episomal iPSC reprogramming vector, and a unique crRNA was designed that does not have similar sequences (≤3 mismatches) anywhere in the human reference genome. In situ gene conversion of the SMN2 gene to an SMN1-like gene in SMA-iPSCs was achieved using CRISPR/Cpf1 and single-stranded oligodeoxynucleotide with a high efficiency of 4/36. Seamlessly gene-converted iPSC lines contained no exogenous sequences and retained a normal karyotype. Significantly, the SMN expression and gems localization were rescued in the gene-converted iPSCs and their derived motor neurons. This is the first report of an efficient gene conversion mediated by Cpf1 homology-directed repair in human cells and may provide a universal gene therapeutic approach for most SMA patients.

Note: Thermal conductivity measurement of individual porous polyimide fibers using a modified wire-shape 3ω method

Porous polyimide fiber enjoys a good reputation as a high temperature resistant thermal insulation material in an aircraft-carrier, a spacecraft, and other military sophisticated products. Understanding its thermal conductivity is especially important for the design optimization and thermal management in these applications. In this study, a modified wire-shape 3ω method is developed to measure the thermal conductivity of individual porous polyimide fibers, utilizing a platinum layer heater/thermometer deposited along the circumferential direction of the fiber. The new method is first validated using a platinum wire with known thermophysical properties such as thermal conductivity at room temperature and then applied to porous polyimide fibers with diverse porosities. The thermal conductivity of porous polyimide fibers at room temperature is 0.06-0.15 W m^-1 K^-1, which reflects a good thermal insulation performance.

Kinetic and equilibrium studies of Cs(I), Sr(II) and Eu(III) adsorption on a natural sandy soil

Radioactive cesium, strontium and europium can be released as fission products during nuclear incidents and pose a major concern to contamination control because of their biological activity and long decay half-lives. Experiments were performed to study the kinetics and equilibrium of the adsorption of inactive Cs(I), Sr(II) and Eu(III) ions on a natural sandy soil. It was found that the adsorption of Cs(I), Sr(II) and Eu(III) had a second order reaction kinetics and generally reached equilibrium within 7 days. The adsorption equilibria of Cs(I) follows a Freundlich isotherm, while those of Sr(II) and Eu(III) follows a Langmuir isotherm. Adsorption increases with increasing pH for these cations studied at temperatures from 25 to 50°C. In general, the temperature effect on cation adsorption is small under these test conditions suggesting that the enthalpy change for adsorption is not significant. Tests of mixed Cs(I) and Sr(II) adsorption suggested that these cations likely adsorb on different sites on the surface of sandy soil. The desorption tests in NaCl and CaCl2 solutions show that Eu(III) and Cs(I) are more tightly bound and less mobile in natural sandy soil than Sr(II) under the same test conditions. Tests of Cs(I), Sr(II) and Eu(III) in a column under a flowing condition revealed that these cations mainly adsorbed within the depth of 2 cm below the surface of sandy soil.