Efficient expression of a novel thermophilic fungal β-mannosidase from Lichtheimia ramosa with broad-range pH stability and its synergistic hydrolysis of locust bean gum

β-Mannosidase (EC 3.2.1.25) is an exoglycosidase specific for the hydrolysis of terminal β-1,4-glycosidic linkage in mannan which can be applied in the food manufacture, animal feed, bioethanol making and coffee extraction industries. A novel β-mannosidase gene (Lrman5A) from Lichtheimia ramosa was synthesized and recombinantly expressed in Pichia pastoris X33. Lrman5A encodes 444 amino acids with a calculated molecular mass of 51.0 kDa which shares the highest identity (73%) with the β-mannosidase from Rhizomucor miehei. Purified recombinant Lrman5A showed the maximal activity at pH 6.0 and 65°C, had broad-range pH stability (retaining >65% activity after incubation at pH 3.0-8.5 at 37°C for 24 h), and was highly thermostable (retaining >80% activity after incubation at 65°C for 10 min). The specific activity, and K_m of Lrman5A was 17.5 U/mg and 1.377 mM, respectively. Lrman5A and GH5 β-mannanase displayed significant synergistic effects on the degradation of locust bean gum (LBG) and released more mannose (up to 2.89 folds) by simultaneous or sequential addition. Due to its hydrolytic properties, Lrman5A may have potential applications in the area of bioenergy, feed and food processing.

Response of AMP-activated protein kinase and lactate metabolism of largemouth bass (Micropterus salmoides) under acute hypoxic stress

To study adaptation of largemouth bass (Micropterus salmoides) to hypoxic stress, we investigated physiological responses and lactate metabolism of the fish under acute hypoxia. The objectives of this study were to (a) observe changes in glucose, glycogen, and lactate content; (b) detect the activity of lactate dehydrogenase (LDH) in serum, brain, heart, and liver tissues; and (c) quantify the dynamic gene expression of AMP activated protein kinase alpha (AMPKα), hypoxia-inducible factor-1 alpha (HIF-1α), monocarboxylate transporter 1 (MCT1), monocarboxylate transporter 4 (MCT4), and lactate dehydrogenase-a (LDHa) following exposure to hypoxia. The fish were subjected to two hypoxia stresses (dissolved oxygen [DO] 1.20 ± 0.2 mg/L and 3.50 ± 0.3 mg/L, respectively) for 24 h. Our results showed that hypoxic stress significantly increased the decomposition of liver glycogen and significantly increased the concentration of blood glucose; however, the muscle glycogen content was not significantly decreased, which indicates that liver glycogen was the main energy source under acute hypoxia. Moreover, hypoxia led to accumulation of a large amount of lactic acid in tissues, possibly due to the activity of lactic acid dehydrogenase, but this process was delayed in the heart and brain relative to the liver. Additionally, hypoxia induced the expression of AMPKα, HIF-1α, MCT1, MCT4, and LDHa, suggesting that glycometabolism had switched from aerobic to anaerobic. Our results contribute to a better understanding of the molecular mechanisms of the response to hypoxia in largemouth bass.

A Catalase-Like Metal-Organic Framework Nanohybrid for O2 -Evolving Synergistic Chemoradiotherapy

Tumor hypoxia, the "Achilles' heel" of current cancer therapies, is indispensable to drug resistance and poor therapeutic outcomes especially for radiotherapy. Here we propose an in situ catalytic oxygenation strategy in tumor using porphyrinic metal-organic framework (MOF)-gold nanoparticles (AuNPs) nanohybrid as a therapeutic platform to achieve O₂ -evolving chemoradiotherapy. The AuNPs decorated on the surface of MOF effectively stabilize the nanocomposite and serve as radiosensitizers, whereas the MOF scaffold acts as a container to encapsulate chemotherapeutic drug doxorubicin. In vitro and in vivo studies verify that the catalase-like nanohybrid significantly enhances the radiotherapy effect, alleviating tumor hypoxia and achieving synergistic anticancer efficacy. This hybrid nanomaterial remarkably suppresses the tumor growth with minimized systemic toxicity, opening new horizons for the next generation of theranostic nanomedicines.

Cortical bone resorption of fibular bone after maxillary reconstruction with a vascularized fibula free flap: a computed tomography imaging study

This study was performed to evaluate the cortical bone resorption of fibular bone after maxillary reconstruction with a fibula free flap. A total of 35 patients with maxillary defects that were repaired using a fibula flap (62 fibula segments) between January 2011 and January 2016 were enrolled. Computed tomography (CT) images taken 1 week and 1 year postoperative were used to evaluate cortical bone resorption. The 62 fibula segments were measured on four different surfaces in the CT images. At 1 week, the thickness of the cortical bone was 2.57 ± 0.58 mm, 2.72 ± 0.46 mm, 3.84 ± 0.98 mm, and 4.36 ± 0.90 mm for the exterior, interior, superior, and inferior sides, respectively. At approximately 1 year, the cortical bone thickness was significantly reduced to 2.00 ± 0.65 mm (P <  0.01), 2.25 ± 0.60 mm (P <  0.01), 3.37 ± 0.90 mm (P <  0.01), and 2.96 ± 0.84 mm (P <  0.01) for the exterior, interior, superior, and inferior sides, respectively. The cortical bone thickness of fibular bone is significantly reduced 1 year after the restoration of maxillary defects with a fibula free flap, most significantly on the inferior side.

In Situ Dendritic Cell Vaccine for Effective Cancer Immunotherapy

A cancer vaccine is an important form of immunotherapy. Given their effectiveness for antigen processing and presentation, dendritic cells (DCs) have been exploited in the development of a therapeutic vaccine. Herein, a versatile polymersomal nanoformulation that enables generation of tumor-associated antigens (TAAs) and simultaneously serves as adjuvant for an in situ DC vaccine is reported. The chimeric cross-linked polymersome (CCPS) is acquired from self-assembly of a triblock copolymer, polyethylene glycol-poly(methyl methyacrylate- co-2-amino ethyl methacrylate (thiol/amine))-poly 2-(dimethylamino)ethyl methacrylate (PEG-P(MMA- co-AEMA (SH/NH₂)-PDMA). CCPS can encapsulate low-dose doxorubicin hydrochloride (DOX) to induce immunogenic cell death (ICD) and 2-(1-hexyloxyethyl)-2-devinyl pyropheophorbide-a (HPPH), a photosensitizer to facilitate photodynamic therapy (PDT) for reactive oxygen species (ROS) generation. This combination is able to enhance the population of TAAs and DC recruitment, eliciting an immune response cascade. In addition, CCPS with primary and tertiary amines act as adjuvant, both of which can stimulate DCs recruited to form an in situ DC vaccine after combination with TAAs for MC38 colorectal cancer treatment. In vivo results indicate that the all-in-one polymersomal nanoformulation (CCPS/HPPH/DOX) increases mature DCs in tumor-draining lymph nodes (tdLNs) and CD8⁺ T cells in tumor tissues to inhibit primary and distant MC38 tumor growth following a single intravenous injection with a low dose of DOX and HPPH.

[A study on the status and problem countermeasures of key occupational disease monitoring in Shandong, China, from 2015 to 2017]

Objective: To analyze the completion status, monitoring results, and existing problems of key occupational disease monitoring in Shandong, China, from 2015 to 2017, and to provide reference materials for improving monitoring quality and carrying out occupational disease prevention and control. Methods: The monitoring situation including project coverage, data collection, monitoring results, and monitoring quality of key occupational diseases in Shandong from 2015 to 2017 were described and comparatively analyzed. Results: In the past three years, the uncoverage rate of monitored counties (38.69% in 2015, 10.95% in 2016, and 5.11% in 2017) , the non-work rate of occupational health examination institutions (41.67% in 2015, 18.02% in 2016, and 8.72% in 2017) , and the non-work rate of occupational disease diagnosis institutions (42.31% in 2015, 38.46% in 2016, and 38.46% in 2017) in Shandong decreased year by year. The number of institutions with key occupational hazard factors reported to the safety supervision and management department increased year by year (it was 24140 in 2017, with an increase of 40.50% compared with 2016 and an increase of 114.62% compared with 2015) ; the key occupational hazard factors in enterprises were mainly noise (72.76%) , followed by benzene, silica dust, and coal dust. The number of workers exposed to key occupational hazard factors reported to the safety supervision and management department increased year by year; in 2017, it was 729245, with an increase of 39.78% compared with 2016 and an increase of 84.81% compared with 2015. The ratio of people exposed to key occupational hazard factors identified by the medical examination to the total people in the safety supervision system in a year decreased year by year (40.87% in 2015, 23.86% in 2016, and 17.95% in 2017) . Conclusion: In Shandong, the supervision of enterprises with key occupational hazard factors and the responsibility of enterprise protection should be strengthened. The occupational health examination rate of workers should be improved. It is suggested that we should carry out the special investigations and occupational health risk assessment for key enterprises and key populations.

Hybrid Nanomedicine Fabricated from Photosensitizer-Terminated Metal-Organic Framework Nanoparticles for Photodynamic Therapy and Hypoxia-Activated Cascade Chemotherapy

During photodynamic therapy (PDT), severe hypoxia often occurs as an undesirable limitation of PDT owing to the O₂ -consuming photodynamic process, compromising the effectiveness of PDT. To overcome this problem, several strategies aiming to improve tumor oxygenation are developed. Unlike these traditional approaches, an opposite method combining hypoxia-activated prodrug and PDT may provide a promising strategy for cancer synergistic therapy. In light of this, azido-/photosensitizer-terminated UiO-66 nanoscale metal-organic frameworks (UiO-66-H/N₃ NMOFs) which serve as nanocarriers for the bioreductive prodrug banoxantrone (AQ4N) are engineered. Owing to the effective shielding of the nanoparticles, the stability of AQ4N is well preserved, highlighting the vital function of the nanocarriers. By virtue of strain-promoted azide-alkyne cycloaddition, the nanocarriers are further decorated with a dense PEG layer to enhance their dispersion in the physiological environment and improve their therapeutic performance. Both in vitro and in vivo studies reveal that the O₂ -depleting PDT process indeed aggravates intracellular/tumor hypoxia that activates the cytotoxicity of AQ4N through a cascade process, consequently achieving PDT-induced and hypoxia-activated synergistic therapy. Benefiting from the localized therapeutic effect of PDT and hypoxia-activated cytotoxicity of AQ4N, this hybrid nanomedicine exhibits enhanced therapeutic efficacy with negligible systemic toxicity, making it a promising candidate for cancer therapy.

Dual acid-responsive bola-type supramolecular vesicles for efficient intracellular anticancer drug delivery

Dual acid-responsive bola-type supramolecular vesicles have been successfully constructed for efficient intracellular anticancer drug delivery and controlled release.

Bifunctional supramolecular prodrug vesicles constructed from a camptothecin derivative with a water-soluble pillar[5]arene for cancer diagnosis and therapy

Bifunctional supramolecular prodrug nanocarriers have been successfully constructed for efficient anticancer drug delivery and tumor diagnosis and therapy.

Parathyroid hormone-stimulation of Runx2 during osteoblast differentiation via the regulation of lnc-SUPT3H-1:16 (RUNX2-AS1:32) and miR-6797-5p

Parathyroid hormone (PTH) acts as a regulator of calcium homeostasis and bone remodeling. Runx2, an essential transcription factor in bone, is required for osteoblast differentiation. Noncoding RNAs such as long noncoding RNAs (lncRNAs) and microRNAs (miRNAs) play crucial roles in regulating gene expression in osteoblasts. In this study, we investigated the effects of PTH on osteoblast differentiation via Runx2, lncRNA, and miRNA expression in human bone marrow stromal cells (hBMSCs) and human osteoblastic cells (MG63). PTH-treatment of hBMSCs for 24 h, 7 days, and 14 days stimulated Runx2 mRNA expression. Using bioinformatics tools, we identified 17 lncRNAs originating from human Runx2 gene. Among these, lnc-SUPT3H-1:16 (RUNX2-AS1:32) expression was highly up-regulated by the 7 d PTH-treatment in hBMSCs. We also identified miR-6797-5p as the putative target of lnc-SUPT3H-1:16 and Runx2 using bioinformatics tools. PTH-treatment increased the expression of miR-6797-5p in hBMSCs, and overexpression of miR-6797-5p decreased osteoblast differentiation in MG63 cells, suggesting a role for lnc-SUPT3H-1:16 as sponge molecule. A luciferase gene reporter assay identified direct targeting of miR-6797-5p with lnc-SUPT3H-1:16 and 3'UTR Runx2 in MG63 cells. Thus, PTH stimulated the expression of lnc-SUPT3H-1:16, miR-6797-5p and Runx2, and due to the sponging mechanism of lnc- SUPT3H-1:16 towards miR-6797-5p, Runx2 was protected, resulting in the promotion of osteoblast differentiation.

Benefits of Etoposide Maintenance Therapy for Patients With Extensive SCLC Who Experienced PR/CR/SD After 4-6 Cycles of First-Line Chemotherapy With Etoposide Plus Cisplatin/Carboplatin

Background: The clinical remission period of small cell lung cancer was shorter after the first-line treatment. Aim: To observe whether oral etoposide maintenance therapy can improve the progression-free survival (PFS) in patients with lung cancer who experienced complete remission (CR), partial remission (PR), and disease stabilization (SD) after 4-6 cycles of first-line chemotherapy with etoposide plus cisplatin/carboplatin. Methods: A retrospective analysis was performed on patients with ED-SCLC who were treated with etoposide (100 mg/d, iv.gtt days 1-5 with a cycle length of every 21 days) plus 4-6 cycles of cisplatin/carboplatin chemotherapy during the period from 1 January 2014 to 31 December 2016 at the Cancer Hospital affiliated with Zhengzhou University. All the patients were divided into 2 groups based on the criteria whether they had gone through maintenance therapy with etoposide: nonmaintained treatment group (NT), and maintenance treatment group (TH). The maintenance treatment group was further subdivided into the 25 mg subgroup (group A) and the 50 mg subgroup (group B) according to the maintenance dose. Analysis of 1-year progression-free survival (PFS) was conducted using the Kaplan-Meier method and Cox proportional hazards model. PFS1 was defined as the first day of first-line treatment until the disease progressed or the last follow-up time. PFS2 was defined as the first day of etoposide capsule treatment until disease progression or the last follow-up time. Results: A total of 85 patients were enrolled in this study; there were 50 patients in the NT group (58.8%) and 35 patients in the TH group (41.2%). In the TH group, there were 10 (28.6%) in the 25 mg subgroup (group A) and 25 (71.4%) in the 50 mg subgroup (group B). Detailed patient information and tumor-related parameters are shown in Table 1. For all patients, the median PFS1 in the first-line regimen with either the cisplatin or carboplatin group was 6.5 months (95% CI: 5.870-7.130) and 6.4 months (95% CI: 5.970-6.970) respectively ( P = 0.0551). Median progression-free survival for all patients and the median PFS for patients of the TH group were 6.5 months (95% CI: 6.138-6.861) and 7.2 months (95% CI: 6.702-7.698) respectively; the median PFS for the NT group, subgroup A, and subgroup B were 5.7 months (95% CI: 4.862-6.478), 6.7 months (95% CI: 6.390-7.010), and 7.4 months (95% CI: 6.386-8.474), respectively ( P = 0.0043). Median PFS2 was 2.400 months for maintenance treatment patients; the median PFS2 in the 25 mg and 50 mg groups was 2.100 months (95% CI 1.690-2.510 months) and 3.030 months (95% CI 1.937-4.123 months), respectively ( P = 0.0309). Conclusion: Use of etoposide capsules to maintain chemotherapy can significantly prolong the progression-free survival (PFS) of CR, PR, and SD in patients with extensive SCLC and improve 1-year survival; a 50-mg dose is better than 25 mg.

Controllable self-assembled plasmonic vesicle-based three-dimensional SERS platform for picomolar detection of hydrophobic contaminants

Hydrophobic contaminants in food and the environment seriously threaten human health. The ultrasensitive detection of these pollutants can minimize their damage. However, current ultrasensitive sensing strategies are limited to solid substrate-based surface-enhanced Raman spectroscopy (SERS) detection. Herein, we report a controllable and reproducible solution-based SERS detection platform for the direct and ultrasensitive detection of hydrophobic contaminants by using self-assembled three-dimensional plasmonic vesicles. To this end, amphiphilic gold nanoparticles (AuNPs) tethered with linear block copolymer (BCP) of polystyrene-b-poly (ethylene oxide) (PS-b-PEO) were designed, which display dual functions for improving detection sensitivity, including serving as building blocks for the construction of plasmonic vesicles to yield large numbers of hot-spots for SERS enhancement, and providing hydrophobic PS layers to enrich and concentrate target hydrophobic molecules for direct SERS detection with hydrophobic interaction. By modulating the AuNP size and the length of BCP chains, the ultrahigh detection sensitivity, down to the picomolar level, was obtained via using 80 nm AuNPs tethered with BCP of PEO45-b-PS900-SH. In addition, the proposed method exhibits excellent reproducibility, universality, practicability, as well as multiplexing detection capacity in actual contaminant-spiked soil samples. Briefly, the designed self-assembled plasmonic vesicle-based SERS platform provides an ideal generic methodology for the ultrasensitive detection of hydrophobic contaminants that can greatly accelerate on-site testing in food and environmental monitoring.

The effect of repeated freeze-thaw cycles on the meat quality of rabbit

<p>We investigated the effect of repeated freeze-thaw cycles on the quality of rabbit meat. Twenty-five Hyla rabbits were slaughtered using standard commercial procedures. A freeze-thaw procedure—i.e., seven days frozen at –18°C followed by thawing at 4°C for 12h— was repeated 5 times, and 9 <em>Longissimus thoracis et lumborum</em> muscles were randomly selected at pre-set cycles (0, 1, 2, 3, and 5). The <em>Longissimus lumborum</em> muscles were used to determine meat quality parameters, while the <em>Longissimus thoracis</em> muscles were used for chemical analysis. During the repeated freeze-thaw process, muscle pH, redness, hardness, and water holding capacity gradually decreased, whereas meat lightness and yellowness gradually increased. The amount of total volatile basic nitrogen significantly increased (<em>P</em>&lt;0.05) and exceeded the threshold value for frozen meat after 5 repeated freeze-thaw cycles. The metmyoglobin proportion, thiobarbituric acid-reactive substances (TBARS) and protein carbonyl content in rabbit meat samples increased with a higher number of freeze-thaw cycles (<em>P</em>&lt;0.05), and the proportions of these compounds were positively correlated. During the repeated freeze-thaw process, extractable haeme iron levels significantly decreased (<em>P</em>&lt;0.05), and non-haeme iron levels markedly increased (<em>P</em>&lt;0.05). An sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis indicated that the degradation of both water- and salt-soluble proteins was more prevalent in samples subjected to higher numbers of freeze-thaw cycles. Additionally, a principal component analysis identified good correlations between physicochemical properties (TBARS, protein carbonyl levels and metmyoglobin content) and quality parameters (thawing loss, redness, lightness and hardness). Taken together, we conclude that the repeated freeze-thaw process can strongly affect rabbit meat quality as well as its physicochemical properties.</p>