[The application of scales and characteristics of disability in the common genotypes of Charcot-Marie-Tooth disease].

Objective: To analyze the correlations among different common scales for evaluating the severity of the first-visit Charcot-Marie-Tooth disease (CMT), and explore the cross-sectional characteristics of neurological dysfunction in patients with four common genotypes (CMT1A, CMT1X, CMT2A and MPZ-related CMT) at their first visits. Methods: A total of 117 genetically confirmed CMT patients (aged ≥10 years) from the Department of Neurology of the Third Xiangya Hospital from 2009 to 2019 were included in the study, which consisted of 45 CMT1A, 41 CMT1X, 19 CMT2A, and 12 MPZ-related CMT patients. Clinical data of these patients at first visits were collected and neurological deficits were evaluated by Charcot-Marie-Tooth Neuropathy Score (CMTNS), Charcot-Marie-Tooth Examination Score (CMTES), Overall Neuropathy Limitation Scale (ONLS) and Functional Disability Scale (FDS). Spearman's correlation was performed to analyze the relationship between CMTNS, CMTES, ONLS and FDS. The age of onset, duration of disease, scores of CMTNS, CMTES, ONLS and FDS were compared among four genotypes. Results: In the 117 CMT patients, the male to female ratio was 1.79/1, and the age of onset was (19±13) years. The duration of disease was 10(3, 15) years, and the scores of CMTNS, CMTES, ONLS and FDS were 11.4±6.2, 8.8±5.7, 2.7±1.4 and 2.6±1.3, respectively. There was a significant correlation between CMTES, ONLS, FDS and CMTNS in the overall CMT patients and four subtypes respectively (r≥0.40, P<0.05). CMTNS, CMTES and ONLS scores of four subtypes showed positive correlations with duration of disease (P<0.05), but FDS scores of CMT1A, CMT1X and MPZ-related CMT patients exhibited no correlation with duration of disease (P>0.05) at their first visits. The age of onset in CMT2A patients was younger than that of the patients with the other three genotypes (P<0.05), furthermore, the scores of four scales in early-onset CMT2A patients were higher than those of adult-onset type CMT2A patients (CMTNS: P=0.031, CMTES: P=0.048, ONLS: P=0.042, FDS: P=0.047). In CMT1X patients, the males had higher scores than those of females for all four scales (CMTNS: P=0.028, CMTES: P=0.014, ONLS: P=0.023, FDS: P=0.002). Conclusions: CMTNS, CMTES and ONLS could be used in natural history studies and clinical trials according to the different clinical situations. In the four genotypes, CMT2A patients have younger age of onset, and the earlier the age of onset, the severer the dysfunction. Moreover, male CMT1X patients relatively have severer neurological dysfunction than female patients.

Nanowire Lasers of Formamidinium Lead Halide Perovskites and Their Stabilized Alloys with Improved Stability.

The excellent intrinsic optoelectronic properties of methylammonium lead halide perovskites (MAPbX3, X = Br, I), such as high photoluminescence quantum efficiency, long carrier lifetime, and high gain coupled with the facile solution growth of nanowires make them promising new materials for ultralow-threshold nanowire lasers. However, their photo and thermal stabilities need to be improved for practical applications. Herein, we report a low-temperature solution growth of single crystal nanowires of formamidinium lead halide perovskites (FAPbX3) that feature red-shifted emission and better thermal stability compared to MAPbX3. We demonstrate optically pumped room-temperature near-infrared (∼820 nm) and green lasing (∼560 nm) from FAPbI3 (and MABr-stabilized FAPbI3) and FAPbBr3 nanowires with low lasing thresholds of several microjoules per square centimeter and high quality factors of about 1500-2300. More remarkably, the FAPbI3 and MABr-stabilized FAPbI3 nanowires display durable room-temperature lasing under ∼10(8) shots of sustained illumination of 402 nm pulsed laser excitation (150 fs, 250 kHz), substantially exceeding the stability of MAPbI3 (∼10(7) laser shots). We further demonstrate tunable nanowire lasers in wider wavelength region from FA-based lead halide perovskite alloys (FA,MA)PbI3 and (FA,MA)Pb(I,Br)3 through cation and anion substitutions. The results suggest that formamidinium lead halide perovskite nanostructures could be more promising and stable materials for the development of light-emitting diodes and continuous-wave lasers.

[Influence of occupational stress on salivary immunoglobulin G concentration in employees].

OBJECTIVE: To investigate the possibility of salivary immunoglobulin G(IgG) as an objective assessment index for occupational stress. METHODS: In September 2014, a total of 186 employees in a solar photovoltaic company were selected as research subjects, and a questionnaire survey was performed. Enzyme-linked immunosorbent assay was used to measure salivary IgG concentration. RESULTS: The salivary IgG concentration showed a significant difference between employees with different working years and shifts(P<0.05). The employees with ≤15 working years had a lower salivary IgG concentration than those with >20 working years (49.93±7.97 µg/ml vs 53.80±8.22 µg/ml), and the employees with long-day shifts had a higher salivary IgG concentration than those with day-night shifts(54.98±7.62 µg/ml vs 51.85±7.94 µg/ml). The employees with low levels of job demands and job danger had a significantly higher salivary IgG concentration than those with high levels(54.09±6.68 µg/ml vs 50.65±8.81 µg/ml, P<0.05; 53.73±7.35 µg/ml vs 50.73±8.73 µg/ml, P<0.05). The employees with a high score of mental health had a significantly higher salivary IgG concentration than those with a low score(54.39±5.28 µg/ml vs 50.73±9.36 µg/ml, P<0.05). The salivary IgG concentration was positively correlated with the score of mental health(r=0.314, P<0.05), but negatively correlated with job demands, job routinization, job danger, job prospects, physical complaints, and daily stress(r=-0.249, -0.159, -0.157, -0.030, -0.035, and -0.176, all P<0.05). The multivariate linear regression analysis showed that the salivary IgG concentration was mainly influenced by job demands and mental health. CONCLUSION: Salivary IgG concentration can be applied as an objective assessment index for occupational stress.

[Correlation between job burnout and salivary cortisol concentration in employees].

OBJECTIVE: To investigate the correlation between job burnout and salivary cortisol concentration. METHODS: In September 2014, a cross-sectional survey was used to perform a questionnaire survey for 237 employees in a solar photovoltaic company. Meanwhile, saliva was collected through chewing with a tube for saliva collection, and enzyme-linked immunosorbent assay was used to measure salivary cortisol concentration. RESULTS: The salivary cortisol concentration showed no significant differences between employees with different ages, working years, educational backgrounds, and shifts(P>0.05). The salivary cortisol concentration was positively correlated with the scores of emotional exhaustion, depersonalization, and job burnout(r=0.182, 0.229, and 0.222, P<0.05). The employees with emotional exhaustion, depersonalization, and job burnout had significantly higher salivary cortisol concentrations than those without emotional exhaustion, depersonalization, and job burnout(80.22±13.34 µg/L vs 75.86±14.75 µg/L, t=2.029, P<0.05; 80.69±12.99 µg/L vs 75.27±14.89 µg/L, t=2.607, P<0.05; 80.06±12.63 µg/L vs 72.76±16.04 µg/L, t=3.248, P<0.05). The stepwise regression analysis showed that salivary cortisol concentration was mainly influenced by depersonalization. CONCLUSION: Job burnout is correlated with salivary cortisol concentration, and can be used as an objective assessment index for job burnout.

[Correlation between occupational stress and salivary cortisol concentration in employees].

OBJECTIVE: To investigate the influence of occupational stress on salivary cortisol concentration in employees. METHODS: In September 2014, occupational stress evaluation was performed for 186 employees in a solar photovoltaic company, and enzyme-linked immunosorbent assay was used to measure the salivary cortisol concentration. RESULTS: The salivary cortisol concentration showed no significant differences between groups with different demographic features(P>0.05). The group with a high score of job control had a significantly lower salivary cortisol concentration than that with a low score(74.62±15.34 µg/L vs 79.95±12.99 µg/L, P<0.05). The groups with high scores of job danger and job responsibility and burden had significantly higher salivary cortisol concentrations than those with low scores(80.29±9.45 µg/L vs 75.60±16.41, P<0.05; 80.94±10.87 µg/L vs 74.05±16.35 µg/L, P<0.05). The salivary cortisol concentration was positively correlated with the scores of job danger and job responsibility and burden(r=0.176 and 0.252, P<0.05) and negatively correlated with the score of job control(r=-0.208, P<0.05). CONCLUSION: Salivary cortisol concentration is positively correlated with occupational stress and increases with the increasing degree of occupational stress, and can be used as an objective biomarker for the identification and evaluation of occupational stress.

[Correlation between job burnout and salivary immunoglobulin G in employees].

OBJECTIVE: To investigate the influence of job burnout on salivary immunoglobulin G(IgG) concentration in employees. METHODS: In September 2014, evaluation of job burnout was performed for 186 employees in a solar photovoltaic company, and enzyme-linked immunosorbent assay was used to measure salivary IgG concentration. RESULTS: The employees with over 20 working years had a significantly higher salivary IgG concentration than those with ≤15 working years(53.80±8.22 µg/ml vs 49.93±7.97 µg/ml, P<0.05). The employees with long-day shifts had a significantly higher salivary IgG concentration than those with day-night shifts (54.98±7.62 µg/ml vs 51.85±7.94 µg/ml, P<0.05). The employees with depersonalization had a significantly lower salivary IgG concentration than those without depersonalization(50.69±9.89 vs 53.19±6.54, P<0.05). The salivary IgG concentration was negatively correlated with the scores of emotional exhaustion, depersonalization, and job burnout (r=-0.194, -0.152, and -0.210, all P<0.05). CONCLUSION: Job burnout is negatively correlated with salivary IgG concentration, which tends to decrease with the increasing severity of job burnout. Therefore, salivary IgG can be used as a biomarker for the identification and evaluation of job burnout.

Two dimensional nanoarrays of individual protein molecules.

Protein molecules on solid surfaces are essential to a number of applications, such as biosensors, biomaterials, and drug delivery. In most approaches for protein immobilization, inter-molecular distances on the solid surface are not controlled and this may lead to aggregation and crowding. Here, a simple approach to immobilize individual protein molecules in a well-ordered 2D array is shown, using nanopatterns obtained from a polystyrene-block-poly(2-hydroxyethyl methacrylate) (PS-b-PHEMA) diblock copolymer thin film. This water-stable and protein-resistant polymer film contains hexagonally ordered PS cylindrical domains in a PHEMA matrix. The PS domains are activated by incorporating alkyne-functionalized PS and immobilizing azide-tagged proteins specifically onto each PS domain using "Click" chemistry. The nanometer size of the PS domain dictates that each domain can accommodate no more than one protein molecule, as verified by atomic force microscopy imaging. Immunoassay shows that the amount of specifically bound antibody scales with the number density of individual protein molecules on the 2D nanoarrays.

Clinical effect of unilateral balloon infusion of low dose bone cement in PKP for osteoporotic thoracolumbar compression fractures in the elderly.

OBJECTIVE: The study was undertaken to determine the clinical effectiveness of percutaneous kyphoplasty (PKP) with unilateral balloon infusion of low dose of bone cement for treatment of osteoporotic vertebral compression fractures (OVCFs) in the elderly. PATIENTS AND METHODS: A retrospective study was carried out. A total of 36 patients with OVCFs treated by PKP from August 2019 and August 2020 were included. Patients were divided into two groups according to the amount of bone cement infused into the vertebral body. The amount of cement in conventional-dose group was 3.5-6.0 mL and the amount of cement in small-dose group was 1.8-3.0 mL. Pain relief before and after the operation were evaluated, and the leakage of bone cement in the two groups was also observed. RESULTS: Two groups of patients have obtained a good clinical efficacy. Pain has significant differences before and after the operation (p < 0.05). More importantly, compared with conventional-dose group, small-dose group has lower bone cement leakage rate (p < 0.05). CONCLUSIONS: PKP with small-dose bone cement infusion can obtain the same clinical effects of conventional-dose, but the incidence of bone cement leakage is lower and safe.

Clinical effect of cement-enhanced APFN in the treatment of elderly osteoporotic intertrochanteric fractures.

OBJECTIVE: To explore the clinical effect of bone cement-enhanced Asian proximal femoral anti-rotation intramedullary nail (APFN) internal fixation in the treatment of elderly osteoporotic intertrochanteric fractures of the femur and provide it as a more robust treatment to elderly patients with osteoporotic intertrochanteric femoral fractures. PATIENTS AND METHODS: Between January 2017 and January 2019, 42 patients with osteoporotic intertrochanteric fractures in our hospital were selected. All patients were randomly divided into the proximal femoral anti-rotation intramedullary nail (PFNA) group and APFN group. The PFNA group received conventional PFNA internal fixation, and the APFN group received bone cement-enhanced APFN internal fixation. The operation time, intraoperative blood loss, average fracture healing time, weight bearing time, and hip function recovery of the two groups of patients were evaluated. RESULTS: All patients were followed up. There was no significant difference in intraoperative blood loss between the two groups. Compared with the PFNA group, the weight-bearing time and hospital stay of the APFN group were significantly shorter. According to the Harris score of hip joint function, the excellent and good rate of the APFN group was better than that of the PFNA group. CONCLUSIONS: Compared with conventional PFNA internal fixation, cement-enhanced APFN internal fixation has the advantage of early functional reconstruction in the treatment of osteoporotic femoral intertrochanteric fractures. It can significantly shorten the time required for patients to get out of bed and bear weight. It is an effective method for the treatment of osteoporotic femoral intertrochanteric fracture.

Evidence of a mobile precursor state in nonspecific protein adsorption.

We study the dynamics of nonspecific protein adsorption using nanometer-micrometer-scale patterns involving hydrophobic domains in hydrophilic matrices. We report the discovery of a critical requirement for the sizes of the hydrophobic/adhesive pads for protein adsorption: the area of each adhesive pad must be more than 2 orders of magnitude larger than the footprint of a protein molecule before irreversible adsorption occurs. We attribute this to the minimal surface area sampled by a mobile protein molecule in a precursor state before irreversible adsorption occurs. Kinetic analysis based on the precursor model quantitatively accounts for the experimental observation and reveals that the distance sampled by the mobile precursor state before irreversible adsorption increases with the size of the protein molecule.

Fluidic and air-stable supported lipid bilayer and cell-mimicking microarrays.

As drug delivery, therapy, and medical imaging are becoming increasingly cell-specific, there is a critical need for high fidelity and high-throughput screening methods for cell surface interactions. Cell membrane-mimicking surfaces, i.e., supported lipid bilayers (SLBs), are currently not sufficiently robust to meet this need. Here we describe a method of forming fluidic and air-stable SLBs through tethered and dispersed cholesterol groups incorporated into the bottom leaflet. Achieving air stability allows us to easily fabricate SLB microarrays from direct robotic spotting of vesicle solutions. We demonstrate their application as cell membrane-mimicking microarrays by reconstituting peripheral as well as integral membrane components that can be recognized by their respective targets. These demonstrations establish the viability of the fluidic and air-stable SLB platform for generating content microarrays in high throughput studies, e.g., the screening of drugs and nanomedicine targeting cell surface receptors.

Molecular helices as electron acceptors in high-performance bulk heterojunction solar cells.

Despite numerous organic semiconducting materials synthesized for organic photovoltaics in the past decade, fullerenes are widely used as electron acceptors in highly efficient bulk-heterojunction solar cells. None of the non-fullerene bulk heterojunction solar cells have achieved efficiencies as high as fullerene-based solar cells. Design principles for fullerene-free acceptors remain unclear in the field. Here we report examples of helical molecular semiconductors as electron acceptors that are on par with fullerene derivatives in efficient solar cells. We achieved an 8.3% power conversion efficiency in a solar cell, which is a record high for non-fullerene bulk heterojunctions. Femtosecond transient absorption spectroscopy revealed both electron and hole transfer processes at the donor-acceptor interfaces. Atomic force microscopy reveals a mesh-like network of acceptors with pores that are tens of nanometres in diameter for efficient exciton separation and charge transport. This study describes a new motif for designing highly efficient acceptors for organic solar cells.

Patterning protein molecules on poly(ethylene glycol) coated Si(111).

We demonstrate spatially localized immobilization of protein molecules on high-density poly(ethylene glycol) (PEG) coated Si(111). Patterns of HO- and CH3O-terminated PEG regions are formed on silicon surfaces based on soft lithography techniques and an efficient reaction between alcohol functional groups and chlorine-terminated silicon. Activation of the HO-terminated PEG brush is achieved via either partial oxidation to form aldehyde groups or via attachment of efficient leaving groups. Protein molecules are covalently immobilized to these activated regions on the PEG/Si surface.

Systemic distribution of Staphylococcus aureus following intradermal footpad challenge of broilers.

We conducted an experiment with broilers to determine if prior exposure to Staphylococcus aureus would facilitate the systemic infiltration of this pathogen following intradermal footpad challenge with live S. aureus. Litter-raised broilers were sensitized at 3 and 4 wk of age with s.c. injections in the neck with heat-killed S. aureus diluted in polyethylene glycol (PEG). Equal numbers of control birds were injected at the same times with PEG. At 7 wk of age, chicks previously sensitized to killed S. aureus or injected with PEG were injected intradermally in the right footpad with PBS or live S. aureus. The left footpads of all birds were injected with PBS. The difference in thickness between the right and left footpads was determined at 0, 24, and 48 h postchallenge. Blood, liver, spleen, lung, and synovial fluid were collected six times between 1 and 48 h postchallenge to determine the recovery of S. aureus. Sensitized and non-sensitized birds showed footpad swelling following challenge with live S. aureus in the right footpad (P < 0.001). Injection of PBS did not induce footpad swelling. Birds injected in the footpads with live S. aureus as compared to PBS had significantly higher isolation rates of S. aureus in the spleen, liver, and blood; however, recovery of S. aureus from S. aureus-sensitized and PEG-injected birds was not significantly different. Time postchallenge (1, 3, 7, 11, 24, and 48 h) had no significant effect on the recovery of S. aureus. It was concluded that the intradermal challenge of the footpad with S. aureus resulted in systemic infiltration of S. aureus into the spleen, liver, and blood. Prior exposures to killed S. aureus as compared to PEG controls did not affect the systemic distribution of S.

Kyphoplasty for the treatment of very severe osteoporotic vertebral compression fracture.

OBJECTIVE: A retrospective evaluation of the clinical outcome and technical feasibility of kyphoplasty for the treatment of very severe osteoporotic vertebral compression fracture (vsOVCF). METHODS: Patients with vsOVCF were treated with kyphoplasty and followed-up for 1 year. Vertebral body height variation, kyphotic angle, back pain (visual analogue scale [VAS]) and Oswestry disability index (ODI) were evaluated preoperatively, postoperatively, 1 month, 3 months and 1 year after treatment. RESULTS: In total, 35 patients (49 vertebrae) were treated with kyphoplasty. There were no cases of spinal or extraspinal injury, infection, bleeding, pulmonary embolism, epidural cement leakage, stroke or cardiac arrest as a result of treatment. There were significant postoperative improvements in all outcome measures (vertebral body height variation, kyphotic angle, VAS and ODI); these improvements were maintained during the follow-up period. CONCLUSION: Kyphoplasty is an effective and minimally invasive procedure for the treatment of vsOVCF.

Immobilization of oligonucleotides on poly(ethylene glycol) brush-coated Si surfaces.

High-density poly(ethylene glycol) (PEG) molecules are grafted onto Si surfaces in a brush-like configuration. We demonstrate that this surface is an excellent substrate for oligonucleotide immobilization. p-Maleimidophenyl isocyanate is used as a heterobifunctional cross-linker to tether thiol-modified oligonucleotides to terminal OH groups on the PEG brush. This approach gives excellent immobilization specificity and low background. The immobilized oligonucleotides show high sensitivity for the detection of complementary targets.