Three-Dimensional-Printed Spherical Hollow Structural Scaffolds for Guiding Critical-Sized Bone Regeneration

The treatment of bone tissue defects continues to be a complex medical issue. Recently, three-dimensional (3D)-printed scaffold technology for bone tissue engineering (BTE) has emerged as an important therapeutic approach for bone defect repair. Despite the potential of BTE scaffolds to contribute to long-term bone reconstruction, there are certain challenges associated with it including the impediment of bone growth within the scaffolds and vascular infiltration. These difficulties can be resolved by using scaffold structural modification strategies that can effectively guide bone regeneration. This study involved the preparation of biphasic calcium phosphate spherical hollow structural scaffolds (SHSS) with varying pore sizes using 3D printing (photopolymerized via digital light processing). The chemical compositions, microscopic morphologies, mechanical properties, biocompatibilities, osteogenic properties, and impact on repairing critical-sized bone defects of SHSS were assessed through characterization analyses, in vitro cytological assays, and in vivo biological experiments. The results revealed the biomimetic properties of SHSS and their favorable biocompatibility. The scaffolds stimulated cell adhesion, proliferation, differentiation, and migration and facilitated the expression of osteogenic genes and proteins, including Col-1, OCN, and OPN. Furthermore, they could effectively repair a critical-sized bone defect in a rabbit femoral condyle by establishing an osteogenic platform and guiding bone regeneration in the defect region. This innovative strategy presents a novel therapeutic approach for assessing critical-sized bone defects.

[Propensity score matching analysis of the short-term efficacy of Kamikawa versus double- tract reconstruction in laparoscopic proximal gastric cancer surgery]

Objective: To compare the short-term efficacy of Kamikawa anastomosis and double-tract reconstruction (DTR) after proximal gastrectomy. Methods: This was a propensity score matched, retrospective, cohort study. Inclusion criteria comprised age 20-70 years, diagnosis of gastric cancer by pathological examination of preoperative endoscopic biopsies, tumor diameter ≤4 cm, and location in the upper 1/3 of the stomach (including the gastroesophageal junction), and TNM stage IA, IB, or IIA. The study cohort comprised 73 patients who had undergone laparoscopic proximal gastric cancer radical surgery in the Department of Gastroenterology, Tangdu Hospital, Air Force Medical University between June 2020 and February 2023, 19 of whom were in the Kamikawa group and 54 in the DTR group. After using R language to match the baseline characteristics of patients in a ratio of 1:2, there were 17 patients in the Kamikawa group and 34 in the DTR group. Surgery-related conditions, postoperative quality of life, and postoperative complications were compared between the two groups. Results: After propensity score matching, there were no statistically significant differences in baseline data between the two groups (P>0.05). Compared with the DTR group, the Kamikawa group had longer operative times (321.5±15.7 minutes vs. 296.8±26.1 minutes, t=32.056, P<0.001), longer anastomosis times (93.0±6.8 minutes vs. 45.3±7.7 minutes, t=56.303, P<0.001), and less bleeding (76 [54~103] mL vs.112 [82~148) mL, Z=71.536, P<0.001); these differences are statistically significant. There were no statistically significant differences between the two groups in tumor size, time to first postoperative passage of gas, postoperative hospital stay, number of lymph nodes removed, duration of lymph node dissection, or total hospitalization cost (all P>0.05). The median follow-up time was 6.1 ± 1.8 months. As to postoperative quality of life, the Kamikawa group had a lower rate of upper gastrointestinal contrast reflux than did the DTR group (0 vs. 29.4% [10/34], χ2=6.220, P=0.013); this difference is statistically significant. However, differences between the two groups in quality of life score on follow-up of 3 months and 6 months on the Gastroesophageal Reflux Disease (GERD) scale were not statistically significant (all P>0.05). The incidence of postoperative complications was 2/17 in the Kamikawa group, which is significantly lower than the 41.2% (14/34) in the DTR group (χ2=4.554, P=0.033). Conclusion: Kamikawa anastomosis and DTR are equally safe and effective procedures for reconstructing the digestive tract after proximal gastric surgery. Although Kamikawa anastomosis takes slightly longer and places higher demands on the surgical team, it is more effective at preventing postoperative reflux.

Prevalence and influencing factors of depressive and anxiety symptoms among hospital-based healthcare workers during the surge period of the COVID-19 pandemic in the Chinese mainland: a multicenter cross-sectional study

BACKGROUND

From November 2022 to February 2023, the Chinese mainland experienced a surge in COVID-19 infection and hospitalization, and the hospital-based healthcare workers (HCWs) might suffer serious psychological crisis during this period. This study aims to assess the depressive and anxiety symptoms among HCWs during the surge of COVID-19 pandemic and to provide possible reference on protecting mental health of HCWs in future infectious disease outbreaks.

METHODS

A multicenter cross-sectional study was carried out among hospital-based HCWs in the Chinese mainland from 5 January to 9 February 2023. The PHQ-9 (nine-item Patient Health Questionnaire) and GAD-7 (seven-item Generalized Anxiety Disorder Questionnaire) were used to measure depressive and anxiety symptoms. Ordinal logistic regression analysis was performed to identify influencing factors.

RESULTS

A total of 6522 hospital-based HCWs in the Chinse mainland were included in this survey. The prevalence of depressive symptoms among the HCWs was 70.75%, and anxiety symptoms was 47.87%. The HCWs who perceived higher risk of COVID-19 infection and those who had higher work intensity were more likely to experience depressive and anxiety symptoms. Additionally, higher levels of mindfulness, resilience and perceived social support were negatively associated with depressive and anxiety symptoms.

CONCLUSION

This study revealed that a high proportion of HCWs in the Chinese mainland suffered from mental health disturbances during the surge of the COVID-19 pandemic. Resilience, mindfulness and perceived social support are important protective factors of HCWs' mental health. Tailored interventions, such as mindfulness practice, should be implemented to alleviate psychological symptoms of HCWs during the COVID-19 pandemic or other similar events in the future.

Comparison between oblique lumbar interbody fusion and posterior lumbar interbody fusion for the treatment of lumbar degenerative diseases: a systematic review and meta-analysis

BACKGROUND

Although oblique lumbar interbody fusion (OLIF) has produced good results for lumbar degenerative diseases (LDDs), its efficacy vis-a-vis posterior lumbar interbody fusion (PLIF) remains controversial. This meta-analysis aimed to compare the clinical efficacy of OLIF and PLIF for the treatment of LDDs.

METHODS

A comprehensive assessment of the literature was conducted, and the quality of retrieved studies was assessed using the Newcastle-Ottawa Scale. Clinical parameters included the visual analog scale (VAS), and Oswestry Disability Index (ODI) for pain, disability, and functional levels. Statistical analysis related to operative time, intraoperative bleeding, length of hospital stay, lumbar lordosis angle, postoperative disc height, and complication rates was performed. The PROSPERO number for the present systematic review is CRD42023406695.

RESULTS

In total, 574 patients (287 for OLIF, 287 for PLIF) from eight studies were included. The combined mean postoperative difference in ODI and lumbar VAS scores was - 1.22 and - 0.43, respectively. In postoperative disc, height between OLIF and PLIF was 2.05. The combined advantage ratio of the total surgical complication rate and the mean difference in lumbar lordosis angle between OLIF and PLIF were 0.46 and 1.72, respectively. The combined mean difference in intraoperative blood loss and postoperative hospital stay between OLIF and PLIF was - 128.67 and - 2.32, respectively.

CONCLUSION

Both the OLIF and PLIF interventions showed good clinical efficacy for LDDs. However, OLIF demonstrated a superior advantage in terms of intraoperative bleeding, hospital stay, degree of postoperative disc height recovery, and postoperative complication rate.

Effect of Segmental Abutting Esophagus-Sparing Technique to Reduce Severe Esophagitis in Limited-Stage Small-Cell Lung Cancer Patients Treated with Concurrent Hypofractionated Thoracic Radiation and Chemotherapy

PURPOSE/OBJECTIVE(S)

To evaluate the effect of segmental abutting esophagus-sparing (SAES) radiotherapy to reduce severe (G3+) acute esophagitis from 20% to 5% in patients with limited-stage small cell lung cancer (LS-SCLC) treated with concurrent chemoradiotherapy.

MATERIALS/METHODS

Patients with a clinical target volume (CTV) ≤1 cm close to the esophagus were enrolled in the experimental arm (45 Gy in 3 Gy daily fractions in 3 weeks) of an ongoing phase III randomized clinical trial (NCT02675088), which enrolled patients with histologically confirmed SCLC and clinically staged as LS or I-IIIB (AJCC 7th). This trial was designed to determine whether HYPO TRT (45 Gy in 3 Gy QD, experimental arm) has the same efficacy as CF TRT (60 Gy in 2 Gy QD, controlled arm) in patients with LS-SCLC. The whole esophagus was divided into the involved esophagus and abutting esophagus (AE) to receive different dose limitations according to the distance from the edge of the CTV. The primary endpoint was grade ≥ 3 acute esophagitis.

RESULTS

From 1 May 2021 to 30 April 2022, 30 patients were enrolled and completed four cycles of planned chemotherapy and radiotherapy. Our patient population was predominantly male (66.7% men vs. 33.3% women), with a median age of 62 years. A majority of patients presented with Stage N2-3 (90.0%) and T2-4 (76.7%), in which 4 patients had ultracentral-located primary tumors. With the SAES technique, all dosimetric parameters were significantly reduced for the whole esophagus and AE. The maximal and mean dose of the esophagus (47.4±1.9 Gy and 13.5 ± 5.8 Gy, respectively) and AE (42.9±2.3 Gy and 8.6 ± 3.6 Gy, respectively) in the SAES plan were significantly lower than those (esophagus 48.0±1.9 Gy and 14.7± 6.1 Gy, AE 45.1±2.4 Gy and 9.8± 4.2 Gy, respectively) in the non-SAES plan. After the follow-up of more than 7 months (range, 7.0-18.1 months) for all patients, only one patient (3.3%, 95% CI 0.1%-17.2%) experienced grade 3 acute esophagitis and no grade 4-5 acute esophagitis happened (Table 3). For late toxicities, one patient suffered sustained grade 1 late esophagitis and all others had no symptoms of esophagitis. The rate of radiation pneumonitis was very low, with one grade 3 event and no grade 4-5 event. Twelve (40.0%) patients had G3+ hematologic toxic events, including 2 patients with febrile neutropenia. The 1-year OS, LRFS, DMFS and PFS was 96.4%, 88.7%, 78.4% and 64.3%, respectively. No patient developed local recurrence in the abutting esophagus-sparing region.

CONCLUSION

SAES radiotherapy has significant dosimetric advantages compared with standard radiotherapy, which are successfully translated into clinical benefits for patients with LS-SCLC treated with 45 Gy in 3 Gy daily fractions. This may facilitate dose escalation for TRT in LS-SCLC patients.

[Establishment of hysteroscopic scoring system of chronic endometritis and correlative analysis with pregnancy outcomes of in vitro fertilization-embryo transfer in infertile patients]

Objective: To establish a hysteroscopic chronic endometritis (hCE) scoring system for patients with chronic endometritis, and observe the correlation of hCE score with in vitro fertilization-embryo transfer (IVF-ET) pregnancy outcomes in infertile women. Methods: The study retrospectively investigated the correlation of morphologic features and hCE score with pregnancy outcomes during IVF-ET in infertile women with CE (n=429) at Yantai Yuhuangding Hospital between January 2017 and September 2018. The clinical pregnancy rate and live birth rate with different score levels (1-3,4-7 and 8-14) after IVF-ET treatment were analyzed. Multivariate regression analysis was performed to adjust for confounding factors. The correlation and regression between hCE score and pregnancy outcomes was analyzed by curve fitting. Results: The age of 429 patients [M(Q₁, Q₃)] was 31 (29, 35) years. There were 50.6% (217 cases), 35.4% (152 cases), and 14.0% (60 cases) of patients with hCE score of 1-3, 4-7, and 8-14, respectively. The pregnancy rates of the three groups were 60.8% (132 cases), 44.7% (68 cases) and 16.7% (10 cases), P<0.001; The live birth rates were 51.2% (111 cases), 36.8% (56 cases) and 13.3% (8 cases), respectively (P<0.001). Compared with patients with hCE of 1-3, pregnancy rates in those with hCE of 4-7 and 8-14 were lower, and the OR values were 0.521 (0.342-0.793) and 0.129 (0.062-0.268). The live birth rates in patients with hCE of 4-7 and 8-14 were lower than that in patients with hCE of 1-3, and the OR values were 0.570 (0.372-0.873) and 0.162 (0.073-0.360), all P<0.05. Quadratic curve fitting results showed that clinical pregnancy rate and live birth rate decreased with the increase of hCE score. Conclusions: With the increase of hCE score, the clinical pregnancy rate and live birth rate of patients gradually decrease. hCE 4 is an important cut-off threshold significantly affecting the pregnancy outcome.

Application of photocrosslinkable hydrogels based on photolithography 3D bioprinting technology in bone tissue engineering

Bone tissue engineering (BTE) has been proven to be an effective method for the treatment of bone defects caused by different musculoskeletal disorders. Photocrosslinkable hydrogels (PCHs) with good biocompatibility and biodegradability can significantly promote the migration, proliferation and differentiation of cells and have been widely used in BTE. Moreover, photolithography 3D bioprinting technology can notably help PCHs-based scaffolds possess a biomimetic structure of natural bone, meeting the structural requirements of bone regeneration. Nanomaterials, cells, drugs and cytokines added into bioinks can enable different functionalization strategies for scaffolds to achieve the desired properties required for BTE. In this review, we demonstrate a brief introduction of the advantages of PCHs and photolithography-based 3D bioprinting technology and summarize their applications in BTE. Finally, the challenges and potential future approaches for bone defects are outlined.

Aneurysmal bone cyst of the temporal bone presenting with reversible vestibular impairment

BACKGROUND

Aneurysmal bone cysts are expansile benign lesions associated with compressive destruction and obscure pathogenesis. The most common sites of temporal bone involvement are the petrous apex, squamous portions and mastoid.

CASE REPORT

This paper reports a right temporal aneurysmal bone cyst in a 51-year-old man who presented clinically with facial palsy, and hearing loss and impaired vestibular function. Magnetic resonance imaging and computed tomography findings were consistent with a diagnosis of aneurysmal bone cyst. Inter-operative findings showed that the lesion had caused compressive damage to the internal auditory canal. Following surgical excision, the patient experienced vertigo, indicating recovery of vestibular function. Follow-up imaging revealed complete resection without clinical recurrence.

CONCLUSION

To our knowledge, this is the first report of aneurysmal bone cyst invasion of the inner auditory canal. Our clinical experience indicates that vestibular nerve damage recovery is relatively uncommon. This case report will hopefully inform future studies.

Foliar application of nanoceria attenuated cadmium stress in okra (Abelmoschus esculentus L.)

Foliar application of nanoparticles (NPs) as a means for ameliorating abiotic stress is increasingly employed in crop production. In this study, the potential of CeO₂-NPs as stress suppressants for cadmium (Cd)-stressed okra (Abelmoschus esculentus) plants was investigated, using two cycles of foliar application of CeO₂-NPs at 200, 400, and 600 mg/l. Compared to untreated stressed plants, Cd-stressed plants treated with CeO₂-NPs presented higher pigments (chlorophyll a and carotenoids). In contrast, foliar applications did not alter Cd root uptake and leaf bioaccumulation. Foliar CeO₂-NPs application modulated stress enzymes (APX, SOD, and GPx) in both roots and leaves of Cd-stressed plants, and led to decreases in Cd toxicity in plant's tissues. In addition, foliar application of CeO₂-NPs in Cd-stressed okra plants decreased fruit Cd contents, and improved fruit mineral elements and bioactive compounds. The infrared spectroscopic analysis of fruit tissues showed that foliar-applied CeO₂-NPs treatments did not induce chemical changes but induced conformational changes in fruit macromolecules. Additionally, CeO₂-NPs applications did not alter the eating quality indicator (Mg/K ratio) of okra fruits. Conclusively, the present study demonstrated that foliar application of CeO₂-NPs has the potential to ameliorate Cd toxicity in tissues and improve fruits of okra plants.

Biomechanical studies of different numbers and positions of cage implantation on minimally invasive transforaminal interbody fusion: A finite element analysis

BACKGROUND

The position and number of cages in minimally invasive transforaminal interbody fusion (MIS-TLIF) are mainly determined by surgeons based on their individual experience. Therefore, it is important to investigate the optimal number and position of cages in MIS-TLIF.

METHODS

The lumbar model was created based on a 24-year-old volunteer's computed tomography data and then tested using three different cage implantation methods: single transverse cage implantation (model A), single oblique 45° cage implantation (model B), and double vertical cage implantation (model C). A preload of 500 N and a moment of 10 Nm were applied to the models to simulate lumbar motion, and the models' range of motion (ROM), ROM ratio, peak stress of the internal fixation system, and cage were assessed.

RESULTS

The ROM ratios of models A, B, and C were significantly reduced by >71% compared with the intact model under all motions. Although there were subtle differences in the ROM ratio for models A, B, and C, the trends were similar. The peak stress of the internal fixation system appeared in model B of 136.05 MPa (right lateral bending), which was 2.07 times that of model A and 1.62 times that of model C under the same condition. Model C had the lowest cage stress, which was superior to that of the single-cage model.

CONCLUSION

In MIS-TLIF, single long-cage transversal implantation is a promising standard implantation method, and double short-cage implantation is recommended for patients with severe osteoporosis.

The Characteristic and Distribution of Shale Micro-Brittleness Based on Nanoindentation

Shale is a special kind of rock mass and it is particularly important to evaluate its brittleness for the extraction of gas and oil from nanoporous shale. The current brittleness studies are mostly macro-evaluation methods, and there is a lack of a micro-brittleness index that is based on nanoindentation tests. In this paper, nanoindentation tests are carried out on the surface of shale to obtain mechanical property, and then a novel micro-brittleness index is proposed. Drawing a heat map by meshing indentation, the distribution characteristics of the brittleness index for the surface of shale and the variation laws between the mineral and brittleness index are explored. The results showed that the dimensionless brittleness index involved parameters including indentation irreversible deformation, elastic modulus, hardness and fracture toughness. The micro-brittleness index of the shale ranged from 7.46 to 65.69, and the average brittleness index was 25.837. The brittleness index exhibited an obvious bimodal distribution and there was great heterogeneity on the surface of shale. The crack propagation channels were formed by connecting many indentation points on the shale surface with high brittleness. The total brittleness index of quartz minerals was high, but the cementation effect with different minerals was various. Although the general brittleness of clay was low, the high brittleness index phenomenon was also exhibited. Studying the micro-brittleness of shale provides a more detailed evaluation for the shale friability, which is used to determine the optimal shale oil and gas recovery regime.

Feasibility Study of a Novel Magnetic Bone Cement for the Treatment of Bone Metastases

Bone cement is a crucial material to treat bone metastases defects, and can fill the bone defect and provide mechanical support simultaneously, but the antitumor effect is very limited. Magnetic bone cement not only supports bone metastasis defects but can also achieve magnetic hyperthermia to eliminate tumor cells around the bone defect. However, the physicochemical properties of the bone cement matrix will change if the weight ratio of the magnetic nanoparticles in the cement is too high. We mixed 1 weight percent Zn_0.3Fe_2.7O₄ with good biocompatibility and high heating efficiency into a polymethyl methacrylate matrix to prepare magnetic bone cement, which minimized the affection for physicochemical properties and satisfied the hyperthermia requirement of the alternating magnetic field.

Characterization and Biomechanical Study of a Novel Magnesium Potassium Phosphate Cement

Magnesium potassium phosphate cement (MKPC) has attracted considerable attention as a bone regeneration material. However, there are only a few reports on its biomechanical properties. To evaluate the biomechanical properties of MKPC, we compared the mechanical parameters of pedicle screws enhanced with either MKPC or polymethyl methacrylate (PMMA) bone cement. The results show that the maximum pull-out force of the pedicle screws was 417.86 ± 55.57 and 444.43 ± 19.89 N after MKPC cement setting for 30 min and 12 h, respectively, which was better than that of the PMMA cement. In fatigue tests, the maximum pull-out force of the MKPC cement group was 435.20 ± 7.96 N, whereas that of the PMMA cement in the control group was 346.80 ± 7.66 N. Furthermore, the structural characterization analysis of the MKPC cement revealed that its microstructure after solidification was an irregular tightly packed crystal, which improved the mechanical strength of the cement. The maximum exothermic temperature of the MKPC reaction was 45.55 ± 1.35 °C, the coagulation time was 7.89 ± 0.37 min, and the compressive strength was 48.29 ± 4.76 MPa, all of which meet the requirements of clinical application. In addition, the MKPC cement did not significantly inhibit cell proliferation or increase apoptosis, thus indicating good biocompatibility. In summary, MKPC exhibited good biomechanical properties, high initial strength, good biocompatibility, and low exothermic reaction temperature, demonstrating an excellent application potential in the field of orthopedics.

Supplemented phase diagrams for vitrification CPA cocktails: DP6, VS55 and M22

DP6, VS55 and M22 are the most commonly used cryoprotective agent (CPA) cocktails for vitrification experiments in tissues and organs. However, complete phase diagrams for the three CPAs are often unavailable or incomplete (only available for full strength CPAs) thereby hampering optimization of vitrification and rewarming procedures. In this paper, we used differential scanning calorimetry (DSC) to measure the transition temperatures including heterogeneous nucleation temperatures (T_het), glass transition temperatures (T_g), rewarming phase crystallization (devitrification and/or recrystallization) temperatures (T_d) and melting temperatures (T_m) while cooling or warming the CPA sample at 5 °C/min and plotted the obtained transition temperatures for different concentrations of CPAs into the phase diagrams. We also used cryomicroscopy cooling or warming the sample at the same rate to record the ice crystallization during the whole process, and we presented the cryomicroscopic images at the transition temperatures, which agreed with the DSC presented phenomena.

Rapidly Progressive Paraplegia Resulting from Latent Cervical Dural Arteriovenous Fistula After Lumbar Surgery: A Case Report

CASE

A 68-year-old woman developed symptoms of acute paraplegia due to an occult cervical dural arteriovenous fistula (DAVF) after a minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF). She was subsequently diagnosed by angiography and treated with vascular embolization. A 2-year follow-up showed that the patient's upper limb muscle strength returned to normal, and the lower limb muscle strength partially improved with remnant motor dysfunction.

CONCLUSION

For patients with symptoms of nerve injury inconsistent with the spinal surgery site, a possibility of DAVF should be considered, and related investigations should be performed. Once diagnosed, active treatment is required.

[Japan narrow-band imaging Expert Team type 2B colorectal cancer: consistency between endoscopic prediction and pathological diagnosis]

OBJECTIVE

To explore the potential factors that affect the accuracy of endoscopic diagnosis for Japan narrow-band imaging (NBI) Expert Team (JNET) type 2B colorectal lesions.

OBJECTIVE

The clinical data were collected from 261 patients with JNET type 2B colorectal lesions diagnosed in Nanfang Hospital between July, 2018 and July, 2021. We analyzed the macroscopic type, size, location or pit pattern classification of the lesions for their potential influence of the diagnostic accuracy of JNET type 2B lesions.

OBJECTIVE

The 261 lesions included 91 low-grade intramucosal neoplasia lesions (34.9%), 132 high-grade intramucosal neoplasia lesions (50.6%), 13 submucosal invasive cancer lesions (5.0%), and 25 deep submucosal invasive cancer lesions (9.6%). The coincidence rate between endoscopic prediction and pathological diagnosis of these lesions was 55.6% (145/ 261). The macroscopic type and size of the lesions were significantly associated with the diagnostic accuracy of JNET type 2B lesions (P < 0.001). There was a significant difference in the diagnostic accuracy among the lesions with different pit pattern types (P < 0.001).

OBJECTIVE

Both the macroscopic type and size affect the accuracy of endoscopic diagnosis of JNET type 2B colorectal lesions. JNET classification combined with pit pattern types can have better accuracy in predicting the pathological diagnosis of these lesions.

SGN nerve filaments develop synapses with IHCs earlier than with OHCs in C57BL/6 mouse inner ear

OBJECTIVE

To explore the connections between hair cells and spiral ganglion neurons (SGNs) during the development of the C57BL/6 mouse inner ear.

MATERIALS AND METHODS

The specimens of C57BL/6 mouse inner ear, from E15 (embryo day 15) to adult mouse, were collected; immunohistochemistry was employed to explore the frozen sections of specimens.

RESULTS

The development of cochlea starts sequentially from the basal turn to the apex turn. Morphological development of SGNs occurs mainly from E16 to P12 (postnatal day 12). Hair cells appear from E18 to P12, and inner hair cells (IHCs) develop earlier than outer hair cells (OHCs). The connections between hair cells and SGNs begin to develop during E18-P1, morphologically resemble mature synapses during P8-P12, and completely mature in adult mice.

CONCLUSIONS

The genesis of auditory ribbon synapse occurs from E18 to P1. Synchronized with the development of SGNs and hair cells, the functional filaments remain connected to hair cells, while the spare ones get disconnected from the surface of hair cells. Connections between SGN nerve filaments and IHCs occur earlier than those between SGN nerve filaments and OHCs.

Effects of supplementation of sea buckthorn press cake on mycelium growth and polysaccharides of Inonotus obliquus in submerged cultivation

AIMS

Investigation of the influence of cultivation time and sea buckthorn press cake (Hippophaë rhamnoides) dosage on mycelium yield of Inonotus obliquus in submerged cultivation and on the yield, monomer composition, and macromolecular properties of the exopolysaccharides (EPS) from culture media and intracellular polysaccharides (IPS) extracted from mycelia.

METHODS AND RESULTS

Supplementation at 5 g l^-1 combined with cultivation time of 250 h granted highest yield increase in mycelia (by 122%). The supplementation reduced extraction yield and decreased the molecular weight of the main IPS population. The supplementation increased production and molecular weight of EPS. The relative content of arabinose and rhamnose in EPS positively correlated with dosage of the press cake. The press cake supplementation increased the content of galacturonic acid in IPS, but not in EPS.

CONCLUSION

Sea buckthorn press cake is a food industry fibrous side stream with high oil content. It increases the cultivation yield of Inonotus obliquus mycelium and influences the produced polysaccharides.

SIGNIFICANCE AND IMPACT OF THE STUDY

Mycelium is a resource of bioactive polysaccharides, attracting the interest of nutraceutical companies. Sea buckthorn press cake is a promising supplement for increasing mycelium production. The utilization of this agricultural side stream would therefore favour circular economy.

Spatial variation of the soil bacterial community in major apple producing regions of China

AIMS

In China, apple production areas are largely from the coastal to inland areas and across varied climate zones. However, the relationship among soil micro-organisms, environmental factors and fruit quality has not been clearly confirmed in orchards. Here we attempted to identify the variation of soil bacteria in the main apple producing regions and reveal the relationship among climatic factor, soil properties, soil bacterial community and fruit quality.

METHODS AND RESULTS

Sixty soil samples were collected from six main apple producing areas in China. We examined the soil bacteria using bacterial 16S rRNA gene amplicon profiling. The results show that the soil bacterial diversity of apple orchards varied from the Bohai Bay Region to the Loess Plateau Region. Proteobacteria, Acidobacteria and Actinobacteria were the predominant taxa at the phylum level for all six areas. In the Bohai Bay and the Loess Plateau region, which are the two largest apple producing areas, Proteobacteria and Actinobacteria had the highest relative abundance, respectively. Furthermore, soil bacterial diversity showed positive correlation with the mean annual temperature (MAT), soil organic matter (SOM) and pH. Excluding a direct effect on the apple fruit quality, MAT exerted an indirect influence through soil SOM and pH to alter the relative abundance of dominant taxa and shift the bacterial diversity, which affects the apple fruit titratable acids and soluble solids.

CONCLUSIONS

Geographic variables underlie apple orchard soil bacterial communities vary according to spatial scale. Environmental factors exert an indirect effect on apple fruit quality via shaping soil bacterial community.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study provides a list of bacteria associated with environmental factors and the ecological attributes of their interactions in apple orchards, which will improve our ability to promote soil bacterial functional capabilities in order to reduce the fertilizer input and enhance the fruit quality.

Influence of mesenchymal stem cells on respiratory distress syndrome in newborn swines via the JAK-STAT signaling pathway

OBJECTIVE

Acute respiratory distress syndrome (ARDS) threatens humans' health worldwide, causing huge labor and economic cost investment. This study aims to explore whether mesenchymal stem cells (MSCs) affect RDS in newborn swines via the Janus kinase-signal transducers and activators of transcription (JAK-STAT) signaling pathway by the establishment of the model of the disease.

MATERIALS AND METHODS

The phosphorylation of the JAK-STAT signal transduction proteins was first detected via Western blotting to verify the regulatory effect of MSCs on RDS in newborn swines through the JAK-STAT signaling pathway. Then, the Reverse Transcription-Polymerase Chain Reaction (RT-PCR) was utilized to analyze the influences of the injection of MSCs into the blood of newborn model RDS swines on inflammatory factors in vivo. To further demonstrate the signal transduction function put forwarded, the RT-PCR and enzyme-linked immunosorbent assay (ELISA) were adopted to analyze the influences of the JAK-STAT signaling pathway inhibitor on the expression of the signature proteins of RDS in newborn swines and the changes in the inflammatory factors.

RESULTS

MSCs induced the phosphorylation of JAK and STAT, and they activated the JAK-STAT signal transduction of RDS in newborn swines. Compared with those in normal saline group, the interleukin (IL)-2, IL-6, IL-8, and tumor necrosis factor-α (TNF-α) expression levels in MSC group were increased, namely, MSCs substantially promoted their expression levels (p<0.05), but those of IL-10 and IL-13 were significantly decreased (p<0.05).

CONCLUSIONS

The inhibitor of the JAK-STAT signaling pathway can suppress the therapeutic effect of MSCs on RDS in newborn swines.

PERSPECTIVE: Critical Cooling and Warming Rates as a Function of CPA Concentration

Cryoprotective agents (CPAs) are routinely applied in cryopreservation protocols to achieve the vitrified state thereby avoiding the damaging effects of ice crystals. Once the CPA has been added, the system needs to cool at a rate ≥ critical cooling rate (CCR) to avoid ice crystallization and successfully enter the vitrified state. Subsequently, upon warming the system needs to meet or exceed a critical warming rate (CWR), often one to two orders of magnitude higher than the CCR, to avoid ice formation and return the system to physiological temperatures for use. Many experimental and theoretical studies have been published on CCRs and CWRs, and correlation for these rates as a function of concentration has been explored for some single component CPAs, but not the CPA cocktails which are commonly used in tissue and organ cryopreservation. In this paper, we summarize the available data of CCRs and CWRs for a variety of CPAs, and suggest a convenient mathematical expression for CCR and CWR that can guide general use for cryoprotective protocol, but also highlights the critical need for further study on CPA cocktails and tissue systems in which CPAs may behave differently and/or may not be fully equilibrated to the loaded CPA.

Ultrafast temporal-spatial dynamics of amorphous-to-crystalline phase transition in Ge2Sb2Te5 thin film triggered by multiple femtosecond laser pulses irradiation

Studies have shown that the crystallization phase state of Ge₂Sb₂Te₅ (GST) can be reversibly modulated by femtosecond (fs) laser multiple pulses, which have excellent applications in reconfigurable multi-level operation fields. In this study, the temporal-spatial crystalline evolution dynamics of amorphous GST film is investigated during two fs laser pulses excitation through a pump-probe shadowgraph imaging technique. A quasi-amorphous phase state, which is different from that in the initial as-deposited amorphous GST, is emerged through the first fs laser pulse excitation with a pulse energy lower than crystallization threshold. The experimental results reveal that a crystallization enhancement effect can be induced through the second pulse excitation based on this quasi-amorphous surface structure. The stimulative cluster generated in the quasi-amorphous reduces the amorphous-to-crystalline phase transition threshold for the second fs laser pulse irradiation. The spatially-resolved phase-transition threshold extension effect in a horizontal direction is proposed with the increasing pulse number to summarize the mechanism of the crystallization enhancement effect. The specific-grain-appearance (coarse grains and fine grains representing different phase transition approach) distributed area induced by single and double fs laser pulses irradiation are experimentally demonstrated corresponding to threshold extension theory.

Apple rootstocks with different phosphorus efficiency exhibit alterations in rhizosphere bacterial structure

AIMS

The purpose of this study was to select phosphorus-efficient apple rootstocks under phosphorus deficiency and to reveal the effects of different apple rootstocks on the rhizosphere bacterial community.

METHODS AND RESULTS

We used 83 hybrid lines of Malus robusta Rehd. × Malling 9 (M.9) to investigate their physiological traits and the phosphorus deficiency phenotypes of leaves in response to phosphorus deficiency (0·1 mmol l^-1 PO₄ ^3- ). All the plants were cultivated in pots in the greenhouse and watered using drip irrigation. In accordance with the results of investigation, we selected the phosphorus-efficient hybrid lines (PE) and the phosphorus-inefficient hybrid lines (PI) to research their root morphology and root hairs (RH). In addition, we used Illumina MiSeq sequencing to determine the bacterial community of the rhizosphere from different rootstocks. The results showed that the PE plants had better growth characteristics and stronger root plasticity than that of the PI plants, and phosphorus deficiency can stimulate the RH growth of PE plants. There was no significant difference in the rhizosphere bacterial diversity, but we found that the bacterial community structure was significantly different at the genus levels; in addition, 89 genera were found to have significant differences between PE and PI plants, especially Bacillus. The PE rhizosphere had more abundant Bacillus compared to the PI. High positive Pearson correlations with the phosphorus concentration in the plantlets of apple rootstocks were detected for the bacterial genera Bacillus (r: 0·776).

CONCLUSIONS

The phosphorus-efficient apple rootstocks adapted to phosphorus deficiency by shaping the root morphology. Notably, different apple rootstocks showed alteration of the microbes in rhizosphere.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study can provide the materials for exploring the mechanism of apple rootstock phosphorus absorption. In accordance with the different bacterial community compositions, we can develop the inoculants to promote nutrient uptake.

HIV-1 genotype is independently associated with immunodeficiency progression among Chinese men who have sex with men: an observational cohort study

OBJECTIVES

HIV-1 genetic diversity is increasing among men who have sex with men (MSM) in China, but the association of HIV-1 genotype with disease progression remains to be elucidated.

METHODS

We collected data in an observational longitudinal cohort study of 860 HIV-1-infected MSM in Guangzhou, China between January 2008 and March 2017. Kaplan-Meier analysis and Cox proportional hazard model were used to predict the time from HIV-1 diagnosis to immunodeficiency progression (CD4 cell count < 200 cells/μl) as well as adjusted hazard ratio (aHR).

RESULTS

CRF01_AE and HIV-1 subtype B infection were associated with higher percentage of patients progressed to immunodeficiency and higher incidence of immunodeficiency than infection with CRF07_BC or CRF55_01B. Compared with CRF07_BC, the time from HIV-1 diagnosis to immunodeficiency were different among the major HIV-1 genotypes, which ranked as follows, in descending order: CRF07_BC (7.03 years) > CRF55_01B (5.71 years, P = 0.014; aHR 3.752, P = 0.0923) > CRF01_AE (5.18 years, P < 0.001; aHR 4.733, P = 0.0152). HIV-1 genotype, viral load and baseline CD4 T-cell count were three independent variables associated with disease progression.

CONCLUSIONS

Our results confirm differential rates of immunodeficiency progression as a function of HIV-1 genotype. The impact of HIV-1 genotype on HIV epidemics, patient management and prevention should be further investigated.

Role of Adult Tissue-Derived Pluripotent Stem Cells in Bone Regeneration

Background

Bone marrow-derived mononuclear cells (BM-MNC) consist of a heterogeneous mix of mesenchymal stem cells (MSC), hematopoietic progenitor cells (HPC), endothelial progenitor cells (EPC), monocytes, lymphocytes and pluripotent stem cells. Whereas the importance of MSC and EPC has been well documented in bone healing and regeneration studies, the role of pluripotent stem cells is still poorly understood. In the present study we evaluated if and how Very Small Embryonic Like cells (VSEL), isolated from rat BM-MNC, contribute to bone healing.

Methods

Large bone defects were made in the femurs of 38 Sprague Dawley female rats and treated with β-TCP scaffold granules seeded with male VSEL; BM-MNC, VSEL-depleted BM-MNC or scaffold alone, and bone healing was evaluated at 8 weeks post-surgery.

Results

Bone healing was significantly increased in defects treated with VSEL and BM-MNC, compared to defects treated with VSEL-depleted BM-MNC. Donor cells were detected in new bone tissue, in all the defects treated with cells, and in fibrous tissue only in defects treated with VSEL-depleted BM-MNC. The number of CD68+ cells was the highest in the VSEL-depleted group, whereas the number of TRAP positive cells was the lowest in this group.

Conclusions

Based on the results, we can conclude that VSEL play a role in BM-MNC induced bone formation. In our rat femur defect model, in defects treated with VSEL-depleted BM-MNC, osteoclastogenesis and bone formation were decreased, and foreign body reaction was increased.

[The hemodynamic study of internal jugular vein in patients with pulsatile tinnitus by color doppler sonography]

Objective:To investigate the hemodynamic changes of internal jugular vein（IJV） in patients with pulsatile tinnitus（PT） detected by color doppler sonography（CDS）. To explore the correlation of PT with IJV drainage dominance and the value of CDS in the diagnosis of PT. Method:Two hundred and twenty-one patients with PT were examined with the CDS and IJV compression test. The hemodynamic data of the upper, middle and lower IJV were compared with both PT side and unaffected side. The correlation of the PT with the IJV drainage dominance was analyzed. Result:A total of 125 cases（56.6%） of 221 patients with PT underwent ultrasonic IJV compression test with positive results, 96 cases（43.3%） with negative results. In the positive compression test group, the tinnitus disappeared after IJV being completely compressed in 109 cases（87.2%）, and in 16 cases（12.8%） after IJV being partial closure. The extent of sectional area reduction was: upper jugular vein（75.41 ±9.39）%, middle jugular vein（80.25±13.16）%, lower jugular vein（86.58± 7.53）%. The blood flow volume on the tinnitus side was obviously higher than that on the unaffected side（P=0.001）. In the negative compression test group, there was no significant difference in blood flow volume between tinnitus side and unaffected side. In the IJV positive compression test group, 54 cases（43.2%） were IJV drainage dominance combined, and 71 cases（56.8%） were non-dominant combined. In the IJV negative compression test group, 24 cases（25%） were IJV drainage dominance combined, and 72 cases（75%） were non-dominant combined. Conclusion:The positive result of IJV compression test using CDS and the flow volume of IJV on the affected side significantly higher than that on the unaffected side contributed to the diagnosis of venous PT. In this study, the IJV non-dominant side was more common in the venous PT.

P4671A well-defined subgroup of chronic thromboembolic pulmonary hypertension patients are positive for antiphospholipid antibodies

Introduction

Recurrent thromboembolism is a major risk factor for chronic thromboembolic pulmonary hypertension (CTEPH). Antiphospholipid antibodies (aPL) are a recognized risk factor for recurrent thromboembolism, however, their contribution to the development of CTEPH is currently unknown.

Purpose

The aim of this study was to evaluate the prevalence of antiphospholipid autoantibodies in a large cohort of consecutive patients with CTEPH.

Methods

Starting May 2013 to December 2018, 297 CTEPHpatients were consecutively enrolled. Diagnosis was confirmed with standardized right heart catheterization, 2D or/and 3D pulmonary angiography in all patients.All patients were also screened for thrombophilia including lupus anticoagulant IgG/IgM anticardiolipin antibodies and IgG/IgM aβ2GPI antibodies. Clinical and demographic characteristics, laboratory profile and hemodynamic data were compared between patients with aPL positive and aPL negative laboratory profiles.

Results

Overall, 297 consecutive patients with CTEPH were assessed for aPLs. Of these, 23 patients (7.7%) resulted positive for laboratory tests exploring aPL. Among patients with positive aPL, profile 17 (74%) were positive for all three test exploring aPL (LA+, aCL+, aB2GPI+). When compared to CTEPH patients without aPL test positivity, those positive for aPL were significantly younger (30.0 vs 55.6 years, p<0.0001), had a positive history of pulmonary embolism (95.6% vs 65.7%, p=0.003), deep venous thrombosis (78.3% vs 41.9%, p=0.0008) and were more frequently affected by other autoimmune diseases (43.5% vs 2.9%, p<0.0001). Moreover, positive aPL patients showed better hemodynamics on right heart catheterization, had more proximal lesions, and had more frequently level I and II surgical classification (82.6% vs 40.5%, p=0.0002) on pulmonary angiography.

Conclusions

These findings suggest that young patients with pulmonary embolism should be assessed for aPLs to guide anticoagulation therapy and prevent recurrences. Additionally, younger age, more proximal lesions and less severe hemodynamic profiles make majority patients with APS good candidates for PEA surgery.

[Analysis of the effect and influencing factors of customized sound on tinnitus]

Objective:To explore the effect and influencing factors of customized sound on tinnitus. Method:303 patients with tinnitus who received customized sound therapy for 6 months were enrolled in this study. Tinnitus handicap inventory (THI) was used to evaluate the treatment effect before treatment, 1 month, 2 months, 3 months, 4 months, 5 months and 6 months after treatment, and the influencing factors of sound treatment effect were analyzed. Result:The THI score decreased at the 1, 2, 3, 4, 5 and 6 months after treatment (P<0.01), compared with that before treatment. Gender, tinnitus type and presence or absence of voice allergy had no effect on THI score before treatment and 6 months after treatment (P>0.05). Conclusion:Customized sound therapy can reduce the score of THI in tinnitus patients, which supports that sound therapy can reduce the negative impact and disturbances produced by tinnitus, and its curative effect is not affected by gender, tinnitus type and presence or absence of voice allergy..

Electrical stimulation shifts healing/scarring towards regeneration in a rat limb amputation model

Different species respond differently to severe injury, such as limb loss. In species that regenerate, limb loss is met with complete restoration of the limbs’ form and function, whereas in mammals the amputated limb’s stump heals and scars. In in vitro studies, electrical stimulation (EStim) has been shown to promote cell migration, and osteo- and chondrogenesis. In in vivo studies, after limb amputation, EStim causes significant new bone, cartilage and vessel growth. Here, in a rat model, the stumps of amputated rat limbs were exposed to EStim, and we measured extracellular matrix (ECM) deposition, macrophage distribution, cell proliferation and gene expression changes at early (3 and 7 days) and later stages (28 days). We found that EStim caused differences in ECM deposition, with less condensed collagen fibrils, and modified macrophage response by changing M1 to M2 macrophage ratio. The number of proliferating cells was increased in EStim treated stumps 7 days after amputation, and transcriptome data strongly supported our histological findings, with activated gene pathways known to play key roles in embryonic development and regeneration. In conclusion, our findings support the hypothesis that EStim shifts injury response from healing/scarring towards regeneration. A better understanding of if and how EStim controls these changes, could lead to strategies that replace scarring with regeneration.

[Comparison of minimally invasive transforaminal lumbar interbody fusion between two approaches in treatment of single-segment lumbar spinal stenosis]

Objective

To compare the effectiveness of minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) with bilateral decompression via unilateral approach and bilateral decompression via bilateral approaches in the treatment of single-segment lumbar spinal stenosis.

Methods

Between February 2015 and January 2017, 70 cases of single-segment lumbar spinal stenosis were treated with MIS-TLIF. The bilateral decompression via unilateral approach (group U) was performed in 36 cases and bilateral decompression via bilateral approaches (group B) in 34 cases. There was no significant difference in age, gender, body mass index, disease duration, distribution of responsibility segments, preoperative visual analogue scale (VAS) score of low back pain and leg pain and Oswestry disability index (ODI) score ( P>0.05). The operation time, intraoperative blood loss, hospitalization stay after operation, complications related to operation, incidence of asymptomatic lateral root symptoms, VAS scores of low back pain and leg pain, and ODI score before and after operation were compared between the two groups. X-ray film and CT scan at 12 months after operation were used to assessted the intervertebral bony fusion.

Results

The operation time and intraoperative blood loss in group U were significantly less than those in group B ( P<0.05). There was no significant difference in hospitalization stay after operation between the two groups ( t=-0.311, P=0.757). During the operation, 1 case in group U and 2 cases in group B had dural tear. No screw placement related nerve injury or asymptomatic lateral root symptoms occurred after operation. The patients were followed up 24 to 38 months, with an average of 32.8 months in group U and 35.5 months in group B. The VAS scores of low back pain and leg pain at 2 days, 3, 6, and 12 months after operation were significantly lower than that before operation in the two groups ( P<0.05), and there was no significant difference between the two groups ( P>0.05). The ODI scores at 3, 6 and 12 months after operation were significantly lower than that before operation in the two groups ( P<0.05), and there was no significant difference between the two groups ( P>0.05). Radiographic examination showed interbody fusion at 12 months after operation in the two groups.

Conclusion

MIS-TLIF is safe and effective in the treatment of single-segment lumbar spinal stenosis with bilateral decompression via unilateral approach and bilateral decompression via bilateral approaches. Bilateral decompression via unilateral approach takes less operation time and has less intraoperative blood loss.

Single-molecule characterization of extrinsic transcription termination by Sen1 helicase

Extrinsic transcription termination typically involves remodeling of RNA polymerase by an accessory helicase. In yeast this is accomplished by the Sen1 helicase homologous to human senataxin (SETX). To gain insight into these processes we develop a DNA scaffold construct compatible with magnetic-trapping assays and from which S. cerevisiae RNA polymerase II (Pol II), as well as E. coli RNA polymerase (ecRNAP), can efficiently initiate transcription without transcription factors, elongate, and undergo extrinsic termination. By stalling Pol II TECs on the construct we can monitor Sen1-induced termination in real-time, revealing the formation of an intermediate in which the Pol II transcription bubble appears half-rewound. This intermediate requires ~40 sec to form and lasts ~20 sec prior to final dissociation of the stalled Pol II. The experiments enabled by the scaffold construct permit detailed statistical and kinetic analysis of Pol II interactions with a range of cofactors in a multi-round, high-throughput fashion.

Yeast’s Sen1 helicase is involved in the suppression of antisense transcription from bidirectional eukaryotic promoters. Here authors develop and utilize a quantitative single-molecule assay reporting on the kinetics of extrinsic eukaryotic transcription termination by the Sen1 helicase and a reaction intermediate in which the Pol II transcription bubble appears half-rewound.

Key factors determining variations in RNA interference efficacy mediated by different double-stranded RNA lengths in Tribolium castaneum

Double-stranded RNA (dsRNA) length may affect RNA interference (RNAi) efficacy. Herein, variation in RNAi efficacy associated with dsRNA molecular length was confirmed via comparison of knockdown results following dsRNA injection into Tribolium castaneum. Through in vitro experiments with T. castaneum midgut, dsRNA accumulation in the midgut, degradation by midgut homogenates and persistence in haemolymph after injection were tested to determine the causes of RNAi efficacy variation. The comparative efficacies of dsRNAs were 480 bp ≈ 240 bp > 120 bp > 60 bp >> 21 bp. The combined midgut dsRNA accumulation and midgut homogenate-induced degradation analyses suggested cellular uptake to be the key barrier for 21 bp dsRNA functioning, but was likely not the main determinant of the variation in longer dsRNAs' (≥60 bp) bioactivity. In vitro RNAi experiment with T. castaneum midgut showed that long dsRNAs all significantly depleted the expression of corresponding genes, suggesting little variation in intracellular RNAi machinery's affinity for different dsRNA lengths. In vivo haemolymph content dynamics of different dsRNAs following injection indicated higher persistence of longer dsRNAs. In addition, comparison of the in vivo and in vitro RNAi efficacy also indicated the importance of haemolymph degradation. Thus, the varied efficacy of long dsRNAs resulted from their degradation by nucleases, which varied with dsRNA length.