Calcaneal fractures: 3D-printing model to assist spatial weaving of percutaneous screws versus conventional open fixation-a retrospective cohort study

PURPOSE

This study compared the clinical effectiveness and wound complications of a three-dimensional model-assisted spatial weaving screw fixation (3D-SWSF) versus open reduction and internal fixation (ORIF) via an L-shaped extensile lateral approach for calcaneal fractures.

METHODS

This single-centre retrospective cohort study was conducted with two cohort groups in which patients with Sanders II and III calcaneal fractures underwent 3D-SWSF or conventional ORIF. The clinical outcome measures included operation duration, time to operation, wound complications, blood loss volume, hospital stays, American Orthopedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot score, and visual analog scale (VAS) score. The pre-operative, post-operative, and one-year follow-up Gissane's angle (GA), Böhler's angle (BA), height, and width and length of the calcaneal fractures were also compared between the two groups.

RESULTS

From Oct 2015 to Oct 2019, 31 patients received 3D-SWSF and 41 received conventional ORIF. A total of 11 (26.8%) patients in ORIF group had wound complications, compared with only two (6.5%) in 3D-SWSF group (p = 0.032). Operative time, blood loss, and hospital stay in 3D-SWSF group were lesser than those in ORIF group. The patients treated with 3D-SWSF had better AOFAS and VAS scores than those treated with ORIF at the last follow-up. The post-operative and one-year follow-up radiographic indexes as well as the GA, BA, length, width, and height of the calcaneal fractures were relatively comparable between the two groups.

CONCLUSION

Our study revealed that 3D-SWSF could effectively decrease the risk of wound complications, shorten operation time, reduce length of hospitalization, and improve post-operative rehabilitation.

The influence of mechanical Circulatory support on post-transplant outcomes in pediatric patients: A multicenter study from the International Society for Heart and Lung Transplantation (ISHLT) Registry

BACKGROUND

Mechanical circulatory support (MCS) is increasingly being used as a bridge to transplant in pediatric patients. We compare outcomes in pediatric patients bridged to transplant with MCS from an international cohort.

METHODS

This retrospective cohort study of heart-transplant patients reported to the International Society for Heart and Lung Transplantation (ISHLT) registry from 2005-2017 includes 5,095 patients <18 years. Pretransplant MCS exposure and anatomic diagnosis were derived. Outcomes included mortality, renal failure, and stroke.

RESULTS

26% of patients received MCS prior to transplant: 240 (4.7%) on extracorporeal membrane oxygenation (ECMO), 1,030 (20.2%) on ventricular assist device (VAD), and 54 (1%) both. 29% of patients were <1 year, and 43.8% had congenital heart disease (CHD). After adjusting for clinical characteristics, compared to no-MCS and VAD, ECMO had higher mortality during their transplant hospitalization [OR 3.97 & 2.55; 95% CI 2.43-6.49 & 1.42-4.60] while VAD mortality was similar [OR 1.55; CI 0.99-2.45]. Outcomes of ECMO+VAD were similar to ECMO alone, including increased mortality during transplant hospitalization compared to no-MCS [OR 4.74; CI 1.81-12.36]. Patients with CHD on ECMO had increased 1 year, and 10 year mortality [HR 2.36; CI 1.65-3.39], [HR 1.82; CI 1.33-2.49]; there was no difference in survival in dilated cardiomyopathy (DCM) patients based on pretransplant MCS status.

CONCLUSION

Survival in CHD and DCM is similar in patients with no MCS or VAD prior to transplant, while pretransplant ECMO use is strongly associated with mortality after transplant particularly in children with CHD. In children with DCM, long term survival was equivalent regardless of MCS status.

Preparation and characterization of paclitaxel palmitate albumin nanoparticles with high loading efficacy: an in vitro and in vivo anti-tumor study in mouse models

BACKGROUND

Combination of the prodrug technique with an albumin nano drug-loaded system is a novel promising approach for cancer treatment. However, the long-lasting and far-reaching challenge for the treatment of cancers lies in how to construct the albumin nanometer drug delivery system with lead compounds and their derivatives.

METHODS

In this study, we reported the preparation of injectable albumin nanoparticles (NPs) with a high and quantitative drug loading system based on the Nab^TM technology of paclitaxel palmitate (PTX-PA).

RESULTS

Our experimental study on drug tissue distribution in vivo demonstrated that the paclitaxel palmitate albumin nanoparticles (Nab-PTX-PA) remained in the tumor for a longer time post-injection. Compared with saline and paclitaxel albumin nanoparticles (Abraxane^®), intravenous injection of Nab-PTX-PA not only reduced the toxicity of the drug in normal organs, and increased the body weight of the animals but maintained sustained release of paclitaxel (PTX) in the tumor, thereby displaying an excellent antitumor activity. Blood routine analysis showed that Nab-PTX-PA had fewer adverse effects or less toxicity to the normal organs, and it inhibited tumor cell proliferation more effectively as compared with commercial paclitaxel albumin nanoparticles.

CONCLUSIONS

This carrier strategy for small molecule drugs is based on naturally evolved interactions between long-chain fatty acids (LCFAs) and Human Serum Albumin (HSA), demonstrated here for PTX. Nab-PTX-PA shows higher antitumor efficacy in vivo in breast cancer models. On the whole, this novel injectable Nab-PTX-PA has great potential as an effective drug delivery system in the treatment of breast cancer.

Genomic and Chemical Investigation of Bioactive Secondary Metabolites From a Marine-Derived Fungus Penicillium steckii P2648

Marine fungi of the genus Penicillium are rich resources of secondary metabolites, showing a variety of biological activities. Our anti-bacterial screening revealed that the crude extract from a coral-derived fungus Penicillium steckii P2648 showed strong activity against some pathogenic bacteria. Genome sequencing and mining uncovered that there are 28 secondary metabolite gene clusters in P2648, potentially involved in the biosynthesis of antibacterial compounds. Chemical isolation and structural determination suggested citrinin is the dominant component of the crude extracts of P2648, and our further tests confirmed that citrinin showed excellent activities against various pathogenic bacteria. Moreover, the gene cluster containing a homolog of the polyketide synthase CitS was identified as the citrinin biosynthesis gene cluster through genetic analysis. Interestingly, three isoquinoline alkaloids were unexpectedly activated and isolated from the Δcits mutant and structural determination by using high-resolution electron spray ionization mass spectroscopy (HRESIMS), 1D, and 2D NMR. Further antibacterial assays displayed that compounds 1 and 2, but not compound 3, showed moderate activities against two antibiotic-resistant pathogenic bacteria with minimum inhibitory concentration (MIC) of 16–32 μg/ml. In conclusion, our results demonstrated that citrinin and isoquinoline alkaloids represent as the major antibacterial agents in the coral-associated fungus P. steckii P2648, and our genomic and chemical analyses present evidence in support of P. steckii P2648 as a potent natural products source for anti-bacterial drug discovery.

Comparative transcriptome analysis reveals different functions of Kandelia obovata superoxide dismutases in regulation of cadmium translocation

Kandelia obovata is a dominant mangrove species in southeastern of China. This species has a high tolerance to heavy metal stress that is mainly ascribed to the thickening of the secondary exodermis and high activity of superoxide dismutase (SOD) enzymes in the roots. The thickened exodermis inhibits entry of heavy metals into the roots, and oxidative stress due to Cd can be reduced efficiently by SOD activity. Although there are several proposed mechanisms by which genes encoding SODs in K. obovata (KoSODs) could induce lignification that contributes to thickening of the root exodermis, the exact functions of FeSOD2 (KoFSD2) and Cu/ZnSOD3 (KoCSD3) remain unclear. In this study we investigated the role of a thickened exodermis in K. obovata root tissues in response to Cd treatment, and determined functions of KoFSD2 and KoCSD3 by performing comparative transcriptome analysis on tobacco lines that overexpress these two enzymes. we found that a thickened exodermis can reduce Cd uptake, and that exposure to high concentrations Cd can promote secondary thickening processes in K. obovata roots exodermis. Transgenic Nicotiana benthamiana overexpressing of KoFSD2 or KoCSD3 exhibit different responses to Cd stress. KoCSD3 can promote thickening of the secondary cell wall of root vascular tissues to impede Cd entry. Meanwhile, KoFSD2 and KoCSD3 can also regulate translocation of copper and iron in response to Cd accumulation. Taken together, our results expand our understanding of the physiological roles of SODs in K. obovata against Cd stress.

First Report of Postharvest Blue Mold decay caused by Penicillium expansum on Lemon (Citrus limon) fruit in China

Lemon (Citrus limon) is one of the most important commercial (both dried and fresh) citrus fruits in China. In the spring of 2019, postharvest blue mold decay was observed at an incidence of 3-5% on lemon fruit at the local markets in Beijing, China. Fruit lesions were circular, brown, soft, and watery, and rapidly expanded at 25°C. To isolate the causal organism, small pieces (2 mm3) were cut from the lesions, surface-sterilized for 1 min in 1.5% NaOCl, rinsed three times with sterilized water, dried with sterile filter paper, placed onto potato dextrose agar (PDA) medium, and incubated at 25°C for 6 days. Eight morphologically similar single-colony fungal isolates were recovered from six lemon fruit. Colony surfaces were bluish-green on the upper surface and cream to yellow-brown one the reverse. Hyphae on colony margins were entirely subsurface and cream in color. Mycelium was highly branched, septate, and colorless, and conidiophores were 250 to 450 × 3.0 to 4.0 µm in size. Stipe of conidiophores were smooth-walled, bearing terminal penicilli, typically terverticillate or less commonly birverticillate, rami occurring singly, 16 to 23 × 3.0 to 4.0 µm, metulae in 3 to 6, measuring 12 to 15 × 3.0 to 4.0 µm. Phialides were ampulliform to almost cylindrical, in verticils of 5 to 8, measuring 8 to 11 × 2.5 to 3.2 µm with collula. Conidia were smooth-walled, ellipsoidal, measuring 3.0 to 3.5 × 2.5 to 3.0 µm. According to morphological characteristics, the fungus was identified as Penicillium expansum (Visagie et al. 2014). For molecular identification, genomic DNA of eight fungal isolates was extracted, regions of the beta-tubulin (TUB), and calmodulin (CAL) genes and ITS region, were amplified using Bt2a/Bt2b, CAL-228F/ CAL-737, and ITS1/ITS4 primers respectively. Obtained sequences of all isolates were identical to sequences of the representative isolate YC-IK12, which was submitted in the GenBank. BLAST results of YC-IK12 sequences (ITS; MT856700: TUB; MT856958: CAL; MT856959) showed 98 to 100% similarity with P. expansum accessions (NR-077154, LN896428, JX141581). For pathogenicity tests, 10 μl of conidial suspension (10 × 105 conidia/ml) from seven-day-old YC-IK12 culture was inoculated using a sterilized needle into the surface of each five asymptomatic disinfected lemons. As a control, three lemons were inoculated using sterile distilled water. All inoculated lemons were placed in plastic containers and incubated at 25°C for 7 days. Decay lesions, identical to the original observations, developed on all inoculated lemons, while control lemons remained asymptomatic. Fungus re-isolated from the inoculated lemon was identified as P. expansum on the basis morphology and Bt2a/Bt2b, CAL-228F/ CAL-737, and ITS1/ITS4 sequences. Previously, Penicillium spp. including P. expansum have been reported as post-harvest pathogens on various Citrus spp. (Louw & Korsten 2015). However, P. digitatum has been reported on lemons and P. expansum has been reported on stored Kiwifruit (Actinidia arguta), Malus, and Pyrus species in China (Tai, 1979; Wang et al. 2015). To our knowledge, this is the first report of blue mold caused by P. expansum on lemons in China. References Louw, J. P., Korsten, L. 2015. Plant Dis. 99:21-30. Tai, F.L. 1979. Sylloge Fungorum Sinicorum. Sci. Press, Acad. Sin., Peking, 1527 pages. 8097 Visagie, C.M. et al. 2014. Studies. Mycol.78: 343. Wang, C. W. et al. 2015. Plant Dis. 99:1037.

First Report of Powdery Mildew Caused by Podosphaera xanthii on Cuphea hyssopifolia (Lythraceae) in Mainland China

Cuphea hyssopifolia (Mexican heather) is a popular evergreen perennial shrub used for ornamental and medicinal purposes. Due to its high ornamental value, it is often used as a ground cover in parks and gardens in China. During February and March 2019 & 2020, powdery mildew was observed on C. hyssopifolia in the districts of Minhou and Jinshan of Fuzhou, China. Disease incidence was 70% but of low severity with only a few older leaves showing yellowing and wilting. Sparse irregular patches of white superficial powdery mildew observed on both sides of mature and young leaves. The powdery mildew fungal appressoria that occurred on epigenous hyphae, were indistinct to nipple-shaped, hyaline, and smooth. Conidiophores were erect, smooth, 80 to 210 × 10 to 12 µm, and produced two to eight crenate-shaped conidia in chains. Foot-cells of conidiophores were straight, cylindric, and 30 to 65 × 10 to12 µm. Conidia were hyaline, smooth, ellipsoid-ovoid to barrel-shaped, 25 to 38 × 16 to 20 µm with distinct fibrosin bodies. Germ tubes were simple to forked and produced from the lateral position of the germinating conidia. No chasmothecia were observed on the surface of infected leaves. Based on the morphology of the imperfect state, the powdery mildew fungus was identified as Podosphaera xanthii (Castagne) U. Braun & N. Shishkoff (Braun and Cook 2012). To confirm fungal identification, total DNA was extracted (Mukhtar et al., 2018) directly from epiphytic mycelia on infected leaves collected from both districts. Internal transcribed spacer (ITS) regions and the partial large subunit (LSU) rDNA were amplified using primers ITS1/ITS4 and LSU1/LSU2 (Scholin et al. 1994, White et al. 1990), respectively. The sequences were deposited in GenBank (ITS: MW692364, MW692365; LSU: MW699924, MW699925). The ITS and LSU sequences were 99 to 100 % identical to those of P. xanthii in GenBank, (ITS: MT568609, MT472035, MT250855, and AB462800; LSU: AB936276, JX896687, AB936277, and AB936274). Koch's postulates were completed by gently pressing diseased leaves onto leaves of five healthy potted C. hyssopifolia plants that were held in a greenhouse at 24 to 30°C without humidity control. Five non-inoculated plants served as controls. Inoculated plants developed symptoms after 6 to 10 days, whereas the controls remained symptomless. The morphology of the fungus on the inoculated leaves was identical to that observed on the originally diseased leaves. Previously, Podosphaera sp. has been reported on C. rosea in the United Kingdom (Beales & Cook 2008) and P. xanthii on C. hyssopifolia in Taiwan (Yeh et al. 2021). To our knowledge, this is the first report of powdery mildew caused by P. xanthii on C. hyssopifolia in mainland China. Our field observations suggest that the P. xanthii infections would be a potential threat to the health of C. hyssopifolia in China. References: Beales, P. A., and Cook, R. T. A. 2008. Plant Pathol. 57:778. Braun, U., Cook, R. T. A. 2012. The Taxonomic Manual of the Erysiphales (Powdery Mildews). CBS Biodiversity Series 11: CBS. Utrecht, The Netherlands. Mukhtar, I., et al. 2018. Sydowia.70:155. Scholin, C. A., et al. 1994. J. Phycol. 30:999. White, T. J., et al. 1990. Page 315 in: PCR Protocols: A Guide to Methods and Applications. Academic Press, San Diego, CA. Yeh, Y. W., et al. 2021. Trop. Plant Pathol. 46:44.

First report of Colletotrichum fructicola causing anthracnose on water hyacinth in China

Water hyacinth (Eichhornia crassipes), a worst invasive aquatic weed has been caused the widespread problems for the water bodies and water resources, particularly the case in China. Plant pathogens are a promising alternative as biocontrol agents (Dagno et al. 2011), but success in this strategy will require the selection of some highly virulent pathogen strains. In September 2020, irregular necrotic lesions on leaves, stems, as well as crown and petiole rots symptoms, occurred on water hyacinth, in Minjiang and Xiyuanjiang watershed, in Fuzhou, China. Fragments from symptomatic leaf tissue (5x5mm) were superficially disinfected in 0.1% MgCl2 solution for 30 s, followed by rinsing three times in sterile water, placed on potato dextrose agar (PDA), and then incubated in darkness at 28°C for 5 days. Two fungal isolates (F3 and F11) were recovered and obtained pure cultures from the affected leaves and deposited in the Institute of Oceanography, Minjiang University. The colonies were stale, with felted, dense, pale grey aerial mycelium, scattered dark based acervuli with orange conidial masses near centre; in reverse side pinkish orange with patches of grey pigment near centre. The hyphae were septate, branched, and 2 to 6 µm in width. Appressoria were not observed. Conidiogenous cells were 20-24 × 3.5-4.5 µm, cylindric to flask-shaped, towards margin the conidiophores with a much looser structure, conidiogenous loci at apex and often also at septa. Asci were 60-80 × 15-20 µm, cylindric to subfusoid, 8-spored. Ascospores were 17-23 × 4-6 µm, gently curved, tapering to quite narrow, rounded ends. Perithecia mature after about 15 days, and were dark brown, subglobose, and 50-150 μm in diameter, and with scattered, dark brown setae about 50-80 µm long. Conidia were 15-25 × 4.5-6 μm, unicellular, colorless, and cylindrical to fusiform. Genomic DNA from two isolates was extracted with a modified DNA Midi Kit (TIANGEN, Inc., Beijing, China), and amplified using ITS4/ITS1F, CL1/CL2A, CHS-79F/CHS-345R, T1/T2 and GDF/GDR primers by PCR (Weir et al. 2012; White et al. 1990). Sequences of F3 and F11 were submitted to GenBank (accession no. ITS, MW307302, MW307303; CAL, MW303427, MW303429; CHS-1, MW303428, MW303430; TUB, MW531006, MW531007; GADPH, MW531008, MW531009). A phylogenetic tree using the maximum likelihood methods and including ITS-CHS-CAL-TUB-GADPH concatenated sequences from Colletotrichum gloeosporioides complex was obtained (Cai et al. 2009; Damm et al. 2018; Weir et al. 2012). Phylogenetic analyses revealed that isolate F3 and F11 were grouped into the clade C. fructicola. To test Koch's postulates, conidial suspensions (107 CFU/ml) of the isolate F3 and F11 were micro-injected into 20 water hyacinth seedlings per isolate. Another 20 seedlings were injected with water without conidia as control. Inoculated plants were kept in 50-liter plastic tanks, and maintained in a greenhouse at room temperature (19-24ºC) for two weeks. The Koch's test was conducted twice. After 10 days, typical anthracnose symptoms similar to the field appeared on the inoculated leaves, while the control leaves remained asymptomatic. The C. fructicola was re-isolated and identified by microscopy, PCR and sequencing, but not on non-inoculated controls. Anthracnose disease caused by C. fructicola has been reported affecting numerous plants worldwide, including cotton, coffea, grape, citrus, ect (Guarnaccia et al. 2017). However, to our knowledge, this is the first report of C. fructicola causing anthracnose on water hyacinth in China. Further studies for the efficacy of C. fructicola and/or of the genus Colletotrichum as biocontrol agent for water hyacinth or another aquatic plant are required (Ding et al. 2007; Dagno et al. 2012).

Oroxylin A attenuates IL-1β-induced inflammatory reaction via inhibiting the activation of the ERK and PI3K/AKT signaling pathways in osteoarthritis chondrocytes

Osteoarthritis (OA) is characterized by degradation of the articular cartilage, synovium inflammation, subchondral bone sclerosis and osteophyte formation. OA is the most common degenerative joint disorder among the elderly population. In particular, currently available therapeutic strategies, such as non-steroidal anti-inflammatory drugs (NSAIDs) may cause severe side-effects. Therefore, novel candidate targets for OA therapy are urgently needed. Oroxylin A (OrA) is a natural mono-flavonoid that can be extracted from Scutellariae radix. The present study aimed to investigate the potential effects of OrA on interleukin (IL)-1β-induced chondrocytes inflammatory reactions. The current study performed quantitative PCR, western blotting and cell immunofluorescence to evaluate the effect of Oroxylin A in chondrocyte inflammation. The results demonstrated that OrA significantly attenuated the upregulation of inducible nitric oxide synthase and cyclooxygenase 2 by IL-1β at both protein and mRNA levels. IL-1β-stimulated upregulation of matrix metalloproteinase (MMP)-3 and MMP-13 expression, in addition to disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS)-4 and ADAMTS-5 expression, were all inhibited by OrA. Treatment with OrA significantly reversed the degradation of type II collagen and aggrecan by IL-1β. Mechanistically, OrA suppressed the IL-1β induced activation of ERK1/2 and PI3K/AKT signaling pathways. In conclusion, these findings suggest that OrA can serve as a potential therapeutic agent for the treatment of OA.

The Treatment of Avulsion Fracture of the Calcaneal Tuberosity: A New Technique of 180-Degree Annular Internal Fixation

Due to the traction of the Achilles tendon and osteoporosis, a large number of reports have shown that a series of complications such as skin flap necrosis and failure of internal fixation after surgery often cause nonunion or malunion of calcaneal tuberosity fractures. At the same time, there is no uniform standard for the operative procedure in the treatment of the avulsion fractures of the calcaneal tuberosity. We presented a new technique for the treatment of avulsion fractures of the calcaneal tuberosity, which is fixed with a 180-degree microplate. We aim to provide a simple, safe, and strong internal fixation technique for avulsion fractures of the calcaneal tuberosity as one of the treatment options.

[Application of the Virtual Reality-Pattern Visual Evoked Potential in Forensic Visual Acuity Evaluation]

Abstract

Objective To explore a kind of visual evoked potential test equipment and method that is more suitable for the application of forensic clinical visual acuity evaluation. Methods Thirty-four volunteers （68 eyes） were selected, including 15 males and 19 females, aged between 20 and 40 years. Test lenses were placed before the tested eyes of volunteers to induce refractive myopia with insert method, and the diopter lenses were adjusted so that the visual acuity level of one eye of volunteers was above 0.8, and the visual acuity of the other eye was at moderate damage level （<0.3 and ≥0.1）. The tests were carried out under the binocular simultaneous asynchronous stimulation mode （hereinafter referred to as "binocular mode"） and monocular separate stimulation mode （hereinafter referred to as "monocular mode"） of virtual reality-pattern visual evoked potential （VR-PVEP）, and the amplitude of PVEP of volunteers under the two modes was compared at four spatial frequencies of 8×8, 16×16, 24×24 and 32×32. Results The differences in the amplitude of P100 wave between monocular and binocular modes at 8×8 spatial frequency had no statistical significance and the differences in amplitude of P100 wave between monocular and binocular modes at 16×16, 24×24, and 32×32 spatial frequencies had statistical significance （P<0.05）. The amplitude of the same eye in monocular mode was higher than that in binocular mode. Through correlation analysis, it was found that the amplitude of P100 wave in monocular mode was moderately correlated with amplitude of P100 wave in binocular mode. Conclusion In forensic identification practice, VR-PVEP is helpful for overcoming the disturbance of poor fixation, and to increase the reliability of PVEP evaluation results. It can greatly shorten the detection time of PVEP and improve work efficiency.

Protective effects of resveratrol liposomes on mitochondria in substantia nigra cells of parkinsonized rats

BACKGROUND

Parkinson's disease (PD) is a central nervous system degenerative disease. The progressive death of dopaminergic neurons is closely correlated to mitochondrial dysfunction. Resveratrol contains three hydroxyl groups, and has a strong neuroprotective effect. This study aimed to investigate the protective effect of resveratrol liposome on mitochondria of substantia nigra cells in Parkinsonized rats through experiment.

METHODS

The investigators used 6-hydroxydopamine to establish the Parkinsonized rat model, and used resveratrol liposome from Polygonum cuspidatum (20 mg·kg-1) for gavage, up to a total volume of 1 mL, once-daily, for two weeks. After treatment, the levels of mitochondrial membrane potential, mitochondrial complexes I-IV, mitochondrial cytochrome C, apoptosis-inducing factor (AIF), PTEN-induced putative kinase 1 (PINK1), tumor necrosis factor-receptor-associated protein 1 (TRAP1) and phosphorylated TRAP1 in rat mesencephalic cells were detected according to the operation instructions of the kits.

RESULTS

After two weeks of treatment, resveratrol liposomes could significantly enhance the activity of mitochondrial electron transfer chain complex I in the substantia nigra cells of Parkinsonized model rats, promote the expression of complex I subcomponent MT-ND1-37kD, improve mitochondrial membrane potential, inhibit the release of mitochondrial cytochrome C and apoptotic inducible factor, enhance the expression of mitochondrial functional protein PINK1, increase the phosphorylated TRAP1 level, and elevate the phosphorylated TRAP1/TRAP1 ratio.

CONCLUSIONS

Resveratrol liposome has positive effects on mitochondria in substantia nigra cells of Parkinsonized rats, and may be one of its pharmacological mechanisms.

Identification of a TetR family regulator and a polyketide synthase gene cluster involved in growth development and butenyl-spinosyn biosynthesis of Saccharopolyspora pogona

Butenyl-spinosyn produced by Saccharopolyspora pogona exhibits strong insecticidal activity and broad pesticidal spectrum. However, its synthetic level was low in the wild-type strain. At present, important functional genes involved in butenyl-spinosyn biosynthesis remain unknown, which leads to difficulty in efficiently editing its genome to improve the butenyl-spinosyn yield. To accelerate the genetic modification of S. pogona, we conducted comparative proteomics analysis to screen differentially expressed proteins related to butenyl-spinosyn biosynthesis. A TetR family regulatory protein was selected from the 289 differentially expressed proteins, and its encoding gene (SP_1288) was successfully deleted by CRISPR/Cas9 system. We further deleted a 32-kb polyketide synthase gene cluster (cluster 28) to reduce the competition for precursors. Phenotypic analysis revealed that the deletion of the SP_1288 and cluster 28 resulted in a 3.10-fold increase and a 35.4% decrease in the butenyl-spinosyn levels compared with the wild-type strain, respectively. The deletion of cluster 28 affected the cell growth, glucose consumption, mycelium morphology, and sporulation by controlling the expression of ptsH, ptsI, amfC, and other genes related to sporulation, whereas SP_1288 did not. These findings confirmed not only that the CRISPR/Cas9 system can be applied to the S. pogona genome editing but also that SP_1288 and cluster 28 are closely related to the butenyl-spinosyn biosynthesis and growth development of S. pogona. The strategy reported here will be useful to reveal the regulatory mechanism of butenyl-spinosyn and improve antibiotic production in other actinomycetes. KEY POINTS: • SP_1288 deletion can significantly promote the butenyl-spinosyn biosynthesis. • Cluster 28 deletion showed pleiotropic effects on S. pogona. • SP_1288 and cluster 28 were deleted by CRISPR/Cas9 system in S. pogona.

Transcriptome Profiling Revealed Multiple rquA Genes in the Species of Spirostomum (Protozoa: Ciliophora: Heterotrichea)

Adaptation to life at different oxygen tensions plays a role in protozoan ecology and controls the distribution of different species in anoxic habitats. The ciliate genus Spirostomum inhabiting fresh or low salinity water globally where these species are considered as bioindicators. Under anaerobic or low oxygen conditions, the rhodoquinol-dependent pathway has been reported in the species from the class Heterotrichea. With the help of RNA sequencing (RNAseq) data, Spirostomum spp., are suitable for deep molecular investigations on rquA for rhodoquinone (RQ) biosynthesis. In this study, Spirostomum ambiguum, Spirostomum subtilis, and Spirostomum teres collected from densely vegetated freshwater habitat in Fuzhou, China, explored the evidence of rquA. Based on transcriptome analysis, two to three RquA proteins were identified in S. ambiguum, S. teres, and S. subtilis, respectively. The presence of a key Motif-I of RquA and mitochondrial targeting signals (MTS), also confirmed the identity of these as RquA. Furthermore, Spirostomum RquA proteins could be sorted into two groups based on their conserved amino acid (CAA) residues. Phylogenetic analysis also exhibited RquA division into two subclades contained RquA1 and RquA2/RquA3 and supports two to three paralogs of rquA genes in the genomes Spirostomum spp. Additional transcriptomes and genomes analysis of Blepharisma spp., and Stentor spp., respectively, also revealed at least two paralogs of rquA in members of the class Heterotrichea. The present study provides evidence for the presence of RquA and rhodoquinol dependent fumarate reduction pathway in Spirostomum species potentially use to respire in the oxygen-depleted habitats and two to three diverse rquA genes.

Study on the anti-infection ability of vancomycin cationic liposome combined with polylactide fracture internal fixator

A polylactide composite fracture fixator loaded with vancomycin cationic liposome (PLA@VL) was prepared by reverse evaporation method. The method of cationic liposome encapsulating vancomycin could effectively improve antibacterial property and achieve drug sustained release effect, so as to reduce toxicity of antibiotics in vivo. Scanning electron microscope (SEM) was used to observe morphology and Fourier transform infrared spectroscopy (FTIR) was used to detect the composition of the internal fixator. In vitro drug release model, in vitro degradation model and body fluid osteogenesis model were designed in this study. On the other hand, the experiments of inhibition zone and MC3T3-E1 osteoblasts in mice were conducted to explore antibacterial property, cell activity and adhesion of the PLA@VL composite internal fixator. Alkaline phosphatase (ALP) staining method and alizarin red assay were used to detect the osteogenic induction ability of the composite internal fixator. Finally, mice fracture models were established to verify osteogenic and anti-infection abilities of the composite internal fixator in vivo. The results showed that MC3T3-E1 cells had better adhesion and proliferation abilities on the PLA@VL composite internal fixator than on the PLA fixator, which indicated that the PLA@VL composite internal fixator possessed excellent osteogenic and anti-infection abilities both in vivo and in vitro. Therefore, the above experiments showed that the fracture internal fixator combined with vancomycin cationic liposome had better biocompatibility, antibacterial ability and osteogenic ability, which provides a promising anti-infection material for the clinical field of fracture.

Lipin 1 deficiency causes adult-onset myasthenia with motor neuron dysfunction in humans and neuromuscular junction defects in zebrafish

Lipin 1 is an intracellular protein acting as a phosphatidic acid phosphohydrolase enzyme controlling lipid metabolism. Human recessive mutations in LPIN1 cause recurrent, early-onset myoglobinuria, a condition normally associated with muscle pain and weakness. Whether and how lipin 1 deficiency in humans leads to peripheral neuropathy is yet unclear. Herein, two novel compound heterozygous mutations in LPIN1 with neurological disorders, but no myoglobinuria were identified in an adult-onset syndromic myasthenia family. The present study sought to explore the pathogenic mechanism of LPIN1 in muscular and neural development.

Methods: The clinical diagnosis of the proband was compared to the known 48 cases of LPIN1 recessive homozygous mutations. Whole-exome sequencing was carried out on the syndromic myasthenia family to identify the causative gene. The pathogenesis of lipin 1 deficiency during somitogenesis and neurogenesis was investigated using the zebrafish model. Whole-mount in situ hybridization, immunohistochemistry, birefringence analysis, touch-evoke escape response and locomotion assays were performed to observe in vivo the changes in muscles and neurons. The conservatism of the molecular pathways regulated by lipin 1 was evaluated in human primary glioblastoma and mouse myoblast cells by siRNA knockdown, drug treatment, qRT-PCR and Western blotting analysis.

Results: The patient exhibited adult-onset myasthenia accompanied by muscle fiber atrophy and nerve demyelination without myoglobinuria. Two novel heterozygous mutations, c.2047A>C (p.I683L) and c.2201G>A (p.R734Q) in LPIN1, were identified in the family and predicted to alter the tertiary structure of LPIN1 protein. Lipin 1 deficiency in zebrafish embryos generated by lpin1 morpholino knockdown or human LPIN1 mutant mRNA injections reproduced the myotomes defects, a reduction both in primary motor neurons and secondary motor neurons projections, morphological changes of post-synaptic clusters of acetylcholine receptors, and myelination defects, which led to reduced touch-evoked response and abnormalities of swimming behaviors. Loss of lipin 1 function in zebrafish and mammalian cells also exhibited altered expression levels of muscle and neuron markers, as well as abnormally enhanced Notch signaling, which was partially rescued by the specific Notch pathway inhibitor DAPT.

Conclusions: These findings pointed out that the compound heterozygous mutations in human LPIN1 caused adult-onset syndromic myasthenia with peripheral neuropathy. Moreover, zebrafish could be used to model the neuromuscular phenotypes due to the lipin 1 deficiency, where a novel pathological role of over-activated Notch signaling was discovered and further confirmed in mammalian cell lines.

[The value of conventional magnetic resonance imaging based radiomic model in predicting the texture of pituitary macroadenoma]

Objective: To investigate the value of conventional magnetic resonance imaging (MRI) based radiomic model in predicting the texture of pituitary macroadenoma. Methods: The complete data of 101 patients with pituitary macroadenoma confirmed by surgery and pathology in Yijishan Hospital of Wannan Medical College from December 2014 to December 2019 were retrospectively analyzed. According to the texture of the intraoperative pituitary tumor, patients were divided into soft group (n=58) and hard group (n=43). They were randomly divided into training group (n=72) and validation group (n=29) at a ratio of 7∶3. All patients underwent conventional MRI scan of the pituitary gland. Itk-snap software was used to manually outline the T(1)-weighted image (T(1)WI), T(2)-weighted image (T(2)WI) and enhanced T(1)WI image section by section on tumor area of interest (ROI) and perform three-dimensional fusion. Then AK software was imported to extract texture features. The regression analysis methods of minimum redundancy maximum relevance (mRMR) and least absolute shrinkage and selection operator (LASSO) were used for feature selection and radiomic signature establishment. The reliability of the model was verified by 100 leave-group-out cross validation (LGOCV), and the predictive ability of the model was evaluated by drawing the receiver operating characteristic (ROC) curve. The decision curve analysis (DCA) was used to evaluate the clinical application value of the model. Results: The AUC (Area Under the ROC Curve) (95%CI) values of T1WI, T2WI, enhanced T1WI, and the combined sequence model to predict the texture of pituitary macroadenomas in the training and validation groups were 0.91 (0.84-0.98) and 0.90 (0.78-1.00), 0.86 (0.78-0.95) and 0.83 (0.64-1.00), 0.90 (0.83-0.97) and 0.89 (0.77-1.00),0.92 (0.85-0.98) and 0.91 (0.79-1.00), respectively. DCA demonstrated that T(1)WI, T(2)WI, enhanced T(1)WI, and combined sequence model all had good net benefits in clinical practice. Conclusions: T(1)WI, T(2)WI, enhanced T(1)WI, and combined sequence model of conventional MRI all had high efficacy in predicting the texture of pituitary macroadenoma, which provided a new quantitative method for predicting the texture of pituitary macroadenoma.

Morusin Inhibits Human Osteosarcoma via the PI3K-AKT Signaling Pathway

OBJECTIVE

Osteosarcoma is considered as one of the most common types of bone tumors, which occurs among adolescents and children.

METHODS

Current therapy strategies still have limited effectiveness therefore, the development of new therapies is urgent. Morusin is a compound isolated from Morus australis (Moraceae). Many studies have reported its anti-tumor effect on several tumor types. However, its role in osteosarcoma is still unclear.

RESULTS

In this study, we determined that morusin significantly suppresses the proliferation and promotes the apoptosis of osteosarcoma cells. Furthermore, the migration and invasion of osteosarcoma were reduced after exposure to morusin. The deep mechanism was determined to be the inhibition of the PI3K/AKT signaling pathway.

CONCLUSION

In conclusion, our study indicates morusin as a potential candidate for osteosarcoma therapy.

ACE2 and Furin Expressions in Oral Epithelial Cells Possibly Facilitate COVID-19 Infection via Respiratory and Fecal-Oral Routes

Background: Coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that mainly transfers from human to human via respiratory and gastrointestinal routes. The S-glycoprotein in the virus is the key factor for the entry of SARS-CoV-2 into the cell, which contains two functional domains: S1 is an angiotensin-converting enzyme 2 (ACE2) receptor binding domain, and S2 is necessary for fusion of the coronavirus and cell membranes. Moreover, it has been reported that ACE2 is likely to be the receptor for SARS-CoV-2. In addition, mRNA level expression of Furin enzyme and ACE2 receptor had been reported in airway epithelia, cardiac tissue, and enteric canals. However, the expression patterns of ACE2 and Furin in different cell types of oral tissues are still unclear. Methods: In order to investigate the potential infective channel of the new coronavirus via the oropharyngeal cavity, we analyze the expression of ACE2 and Furin in human oral mucosa using the public single-cell sequence datasets. Furthermore, immunohistochemistry was performed in mucosal tissue from different oral anatomical sites to confirm the expression of ACE2 and Furin at the protein level. Results: The bioinformatics results indicated the differential expression of ACE2 and Furin on epithelial cells from different oral anatomical sites. Immunohistochemistry results revealed that both the ACE2-positive and Furin-positive cells in the target tissues were mainly positioned in the epithelial layers, partly expressed in fibroblasts, further confirming the bioinformatics results. Conclusions: Based on these findings, we speculated that SARS-CoV-2 could invade oral mucosal cells through two possible routes: binding to the ACE2 receptor and fusion with cell membrane activated by Furin protease. Our results indicated that oral mucosa tissues are susceptible to SARS-CoV-2 that could facilitate COVID-19 infection via respiratory and fecal-oral routes.

Tachyplesin induces apoptosis in non-small cell lung cancer cells and enhances the chemosensitivity of A549/DDP cells to cisplatin by activating Fas and necroptosis pathway

Cisplatin has strong broad-spectrum anticancer activity and is one of the most effective anticancer drugs currently used. The clinical application of cisplatin has led to the resistance of cancer cells to cisplatin. Tachyplesin is an active, natural marine peptide with antitumour activity. In the present study, we investigated whether tachyplesin can be used in non-small cell lung cancer (NSCLC) A549 and H460 cells as well as the cisplatin-resistant human A549/DDP NSCLC cell line. The results revealed that tachyplesin treatment significantly inhibited proliferation and induced apoptosis in A549 and H460 cells and the combination of tachyplesin and cisplatin significantly suppressed migration and improved sensitivity to cisplatin in A549/DDP cells. Further mechanistic examination revealed that tachyplesin induced apoptosis in A549/DDP cells by increasing Fas, FasL and p-RIPK1 levels. These results indicated that tachyplesin induces lung cancer death by activating the Fas, mitochondrial and necroptosis pathways. Tachyplesin could be developed as a candidate drug for cisplatin-resistant NSCLC.

Study on the cellular internalization mechanisms and in vivo anti-bone metastasis prostate cancer efficiency of the peptide T7-modified polypeptide nanoparticles

Bone-metastasis prostate cancer (BMPCa)-targeting gene therapy is gaining increasing concern in recent years. The peptide T7-modified polypeptide nanoparticles for delivery DNA (CRD-PEG-T7/pPMEPA1) was prepared as our previous study. However, the feasibility of CRD-PEG-T7/pPMEPA1 for BMPCa treatment, the mechanisms underlying cellular uptake, anti-BMPCa effect, and administration safety requires further research. LNCaP cells treated with endocytosis inhibitors and excessive T7 under different culture condition were carried out to investigate the mechanisms of cellular uptake of the CRD-PEG-T7-pPMEPA1. A transwell assay was applied to evaluate the cell migration ability. Besides, the tumor volume and survival rates of the PCa xenograft mice model were recorded to estimate the anti-tumor effect. In addition, the weight profiles of the PCa tumor-bearing mice, the blood chemistry, and the HE analysis of visceral organs and tumor was conducted to investigate the administration safety of CRD-PEG-T7/pPMEPA1. The results showed that PCa cellular uptake was decreased after treating with excessive free T7, endocytosis inhibitors and lower incubation temperature. Besides, CRD-PEG-T7/pPMEPA1 could inhibit the LNCaP cells chemotaxis and tumor growth. In addition, the survival duration of the PCa tumor-bearing mice treating with CRD-PEG-T7/pPMEPA1 was significantly prolonged with any systemic toxicity or damage to the organs. In conclusion, this research proposes a promising stratagem for treatment BMPCa by providing the biocompatible and effective carrier for delivery DNA therapeutic agents.

Identification of the origin of brain metastases based on the relative methylation orderings of CpG sites

Accurate diagnosis of the origin of brain metastases (BMs) is crucial for tailoring an effective therapy to improve patients' prognosis. BMs of unknown origin account for approximately 2-14% of patients with BMs. Hence, the aim of this study was to identify the original cancer type of BMs based on their DNA methylation profiles. The DNA methylation profiles of glioma (GM), BM, and seven other types of primary cancers were collected. In comparison with GM, the reversal CpG site pairs were identified for each of the seven other types of primary cancers based on the within-sample relative methylation orderings (RMOs) of the CpG sites. Then, using the reversal CpG site pairs, GMs were distinguished from BMs and the seven other types of primary cancers. All 61 of the GM samples were correctly identified as GM. The cancer type was also identified for the non-GM samples. For the seven other types of primary cancers, greater than 93% of samples of each cancer type were correctly identified as their corresponding cancer type, except for breast cancer, which had an 88% accuracy. For 133 BM samples, 132 BM samples were identified as non-GM, and 95% of the 133 BM samples were correctly classified into their corresponding original cancer types. The RMO-based method can accurately identify the origin of BMs, which is important for precision treatment.

Effects of lytS-L on the primary metabolism and butenyl-spinosyn biosynthesis in Saccharopolyspora pogona

The LytTR family two-component system widely exists in bacterial cells and plays an important role in metabolic regulation. The lytS-L gene that encodes for a LytTR family sensor kinase was knocked out to study its influence on the growth, phenotype, and the biosynthesis of the insecticidal polyketide butenyl-spinosyn in Saccharopolyspora pogona NRRL 30141 (S. pogona). High performance liquid chromatography (HPLC) results showed that the butenyl-spinosyn yield of the lytS-L knockout mutant decreased by 58.9% compared with that of the parental strain. This is manifested by a weak toxicity of the mutant against the insect Helicoverpa assulta (H. armigera). Comparative proteomic analysis revealed the expression characteristics of the proteins in S. pogona and S. pogona-ΔlytS-L: a total of 14 proteins involved in energy metabolism were down-regulated, 9 proteins related to carbon metabolism such as glycolysis, and tricarboxylic acid cycle (TCA) were up-regulated, while 13 proteins involved in the biosynthesis of butenyl-spinosyn were down-regulated (fold change >1.2 or< 0.83). The qRT-PCR (Quantitative Real-time PCR) analysis illustrated that the changes in the expression levels of transcription and translation of the identified genes were consistent. This study explores the function of the two-component system of the LytTR family in S. pogona and shows that the lytS-L gene has an important influence on regulating primary metabolism and butenyl-spinosyn biosynthesis of S. pogona.

α-Synuclein amplifies cytoplasmic peroxide flux and oxidative stress provoked by mitochondrial inhibitors in CNS dopaminergic neurons in vivo

Convergent evidence implicates impaired mitochondrial function and α-Synuclein accumulation as critical upstream events in the pathogenesis of Parkinson's disease, but comparatively little is known about how these factors interact to provoke neurodegeneration. We previously showed that α-Synuclein knockdown protected rat substantia nigra dopaminergic neurons from systemic exposure to the mitochondrial complex I inhibitor rotenone. Here we show that motor abnormalities prior to neuronal loss in this model are associated with extensive α-Synuclein-dependent cellular thiol oxidation. In order to elucidate the underlying events in vivo we constructed novel transgenic zebrafish that co-express, in dopaminergic neurons: (i) human α-Synuclein at levels insufficient to provoke neurodegeneration or neurobehavioral abnormalities; and (ii) genetically-encoded ratiometric fluorescent biosensors to detect cytoplasmic peroxide flux and glutathione oxidation. Live intravital imaging of the intact zebrafish CNS at cellular resolution showed unequivocally that α-Synuclein amplified dynamic cytoplasmic peroxide flux in dopaminergic neurons following exposure to the mitochondrial complex I inhibitors MPP⁺ or rotenone. This effect was robust and clearly evident following either acute or prolonged exposure to each inhibitor. In addition, disturbance of the resting glutathione redox potential following exogenous hydrogen peroxide challenge was augmented by α-Synuclein. Together these data show that α-Synuclein is a critical determinant of the redox consequences of mitochondrial dysfunction in dopaminergic neurons. The findings are important because the mechanisms underlying α-Synuclein-dependent reactive oxygen species fluxes and antioxidant suppression might provide a pharmacological target in Parkinson's disease to prevent progression from mitochondrial dysfunction and oxidative stress to cell death.

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Extensive neuronal thiol oxidation in a rat PD model is α-Synuclein-dependent.

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Peroxide flux and glutathione oxidation can be imaged in live transgenic zebrafish.

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α-Synuclein amplifies cytosolic peroxide flux in dopaminergic neurons.

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α-Synuclein exacerbates dynamic disturbances of the glutathione redox potential.

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The underlying molecular mechanisms may provide therapeutic targets in PD.

Posterior short segment fixation including the fractured vertebra combined with kyphoplasty for unstable thoracolumbar osteoporotic burst fracture

BACKGROUND

Various studies have described the efficacy and safety of the treatment for unstable thoracolumbar osteoporotic burst fracture, however, there is still no consensus on the optimal treatment regimen. The aim of this study was to evaluate the clinical and radiographic results of posterior short segment fixation including the fractured vertebra (PSFFV) combined with kyphoplasty (KP) for unstable thoracolumbar osteoporotic burst fracture.

METHODS

Forty-three patients with unstable thoracolumbar osteoporotic burst fracture underwent PSFFV combined with KP from January 2015 to December 2017 were analyzed retrospectively. Visual Analogue Scale (VAS) and Oswestry Disability Index (ODI) was used to evaluate the clinical outcome, radiological parametres including local kyphotic Cobb angle, percentage of the anterior, middle and posterior height of the fractured vertebra were measured and compared pre-operation, post-operation and at final follow-up.

RESULTS

All patients underwent surgery successfully and with an average follow-up of 19.2 ± 6.7 months (rang 15-32). The VAS decreased from 7.1 ± 2.3 pre-operation to 1.6 ± 0.4 at the final follow-up (p < 0.05). The ODI decreased from 83.1 ± 10.5 pre-operation to 19.2 ± 7.3 (P < 0.05) at the final follow-up. The correction of local kyphotic angle was 16.9° ± 5.3° (p < 0.05), and the loss of correction was 3.3° ± 2.6° (p > 0.05), the correction of anterior vertebral height was 30.8% ± 8.6% (p < 0.05), and the loss of correction was 4.5% ± 3.9% (p > 0.05), the correction of middle vertebral height was 26.4% ± 5.8% (p < 0.05), and the loss of correction was 2.0% ± 1.6% (p > 0.05), the correction of posterior vertebral height was 9.4% ± 6.9% (p < 0.05), and the loss of correction was 1.6% ± 1.3% (p > 0.05). Two cases of screw pullout and 8 cases of cement leakage were observed, but without clinical consequence.

CONCLUSIONS

PSFFV combined with KP is a reliable and safe procedure with satisfactory clinical and radiological results for the treatment of unstable thoracolumbar osteoporotic burst fracture.

SenX3-RegX3, an Important Two-Component System, Regulates Strain Growth and Butenyl-spinosyn Biosynthesis in Saccharopolyspora pogona

Butenyl-spinosyn produced by Saccharopolyspora pogona exhibits strong insecticidal activity and a broad pesticidal spectrum. Currently, important functional genes involved in butenyl-spinosyn biosynthesis remain unknown, which leads to difficulty in efficient understanding of its regulatory mechanism and improving its production by metabolic engineering. Here, we present data supporting a role of the SenX3-RegX3 system in regulating the butenyl-spinosyn biosynthesis. EMSAs and qRT-PCR demonstrated that RegX3 positively controls butenyl-spinosyn production in an indirect way. Integrated proteomic and metabolomic analysis, regX3 deletion not only strengthens the basal metabolic ability of S. pogona in the mid-growth phase but also promotes the flow of the acetyl-CoA produced via key metabolic pathways into the TCA cycle rather than the butenyl-spinosyn biosynthetic pathway, which ultimately leads to continued growth but reduced butenyl-spinosyn production. The strategy demonstrated here may be valuable for revealing the regulatory role of the SenX3-RegX3 system in the biosynthesis of other natural products.

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Butenyl-spinosyn biosynthesis is highly sensitive to Pi control

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RegX3 regulates polyP accumulation in S. pogona

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RegX3 may indirectly regulate butenyl-spinosyn production

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RegX3 plays an important role in the normal growth development of S. pogona

ACY‑1215, a HDAC6 inhibitor, decreases the dexamethasone‑induced suppression of osteogenesis in MC3T3‑E1 cells

Glucocorticoid-induced osteoporosis is the commonest form of drug-induced osteoporosis. Histone deacetylase 6 (HDAC6) is involved in the differentiation from mesenchymal stem cells to osteoblasts. However, the role of ricolinostat (ACY-1215, HDAC6 inhibitor) in the dexamethasone (Dex)-induced proliferation and differentiation of preosteoblasts remains to be elucidated. The protein expression and mRNA expression levels of HDAC6, osteopontin (OPN), runt-related transcription factor 2 (Runx2), osterix (Osx), collagen I (COL1A1) and glucocorticoid receptor (GR) in MC3T3-E1 cells were analyzed by western blot analysis and reverse transcription-quantitative PCR analysis. The cell viability was detected by CCK-8 assay. The alkaline phosphatase (ALP) activity and capacity of mineralization was determined by ALP assay kit and alizarin red staining. HDAC6 expression was increased in patient serum and Dex-induced MC3T3-E1 cells at a certain concentration range; 1 µM Dex was selected for further experimentation. Cell viability was decreased after Dex induction and restored following ACY-1215 treatment. The ALP activity and capability for mineralization was decreased when MC3T3-E1 cells were induced by 1 µM Dex and was gradually improved by the treatment of ACY-1215 at 1, 5 and 10 mM. The expression of OPN, Runx2, Osx and COL1A1 was similar, with the changes of capability for mineralization. Furthermore, GR expression was increased in Dex-induced MC3T3-E1 cells. ACY-1215 promoted the GR expression in MC3T3-E1 cells from 1–5 mM while GR receptor expression was increased with 10 mM ACY-1215 treatment. In conclusion, ACY-1215 reversed the Dex-induced suppression of proliferation and differentiation of MC3T3-E1 cells.

[Influence on physical development of children aged 18 months from HIV-positive mothers for prevention mother to child transmission of HIV]

Objective: To explore influence on physical development of children aged 18 months from HIV-positive mothers for prevention mother to child transmission of HIV (PMTCT) in Guangxi Zhuang autonomous region, and provide evidence for the improvement PMTCT program. Methods: This retrospective case control study was conducted in 554 HIV negative infants aged 18 months whose HIV positive mothers had received PMTCT services reported through PMTCT system database from January 1, 2010 to December 31, 2017 and 1 109 healthy infants born in 2017, whose mothers were healthy, in Lingshan, Luzhai, and Hengxian counties, ranking top three counties with high HIV infection prevalence, in Guangxi. PMTCT data and physical development data such as height, weight and head circumference of children aged 18 months were collected. The physical dysplasia in the infants was defined as at least one of the three main indicators of height, weight and head circumference below the normal range. Results: The number of HIV-positive mother and their infants in the case group were 667 and 554 respectively, and the PMTCT rates were 91.15% (608/667) and 96.57% (535/554) respectively. HIV positive rate, mortality rate and mother to child transmission rate of the infants aged 18 months were 1.44% (8/554), 3.07% (17/554) and 1.91% (8/418) respectively, and the physical examination results of the infants aged 18 months showed that the physical dysplasia rate was 30.51% (169/554). Among the 1 109 infants in the control group, the physical dysplasia rate was 9.83% (109/1 109). The difference between the case group and the control group was significant (P<0.01). Conclusion: The PMTCT rates of HIV positive mother and their children were more than 90.00%, respectively. However, poor physical development rate of infants aged 18 months were more than 30.00%. The possible influence of PMTCT on physical development of the infants aged 18 months of HIV positive mother's needs to be further studied.

Exploring electronic and optical properties of Ge-based perovskites under strain: Insights from the first-principles calculations

Organic-inorganic hybrid perovskites have attracted extensive attention as promising photovoltiac materials for high-efficiency solar cells. In this study, strain effects on the material properties of Ge-based perovskites are fully investigated by the first-principles calculations. The results indicate that the structural, mechanical, electronic and optical properties of CH₃NH₃GeX₃ (X = Cl, Br, I) are sensitive to external modulations. The band gaps of three Ge-based halide perovskites are well predicted by using the HSE06 functional. By increasing the compressive strain, the band gaps of three compounds decrease. A suitable band gap (1.36 eV) of CH₃NH₃GeI₃ can be obtained under a strain of -3%. Moreover, the calculated elastic constants further imply that this compound is stable under this condition. The relationship between the band gap variation and geometry change under the compressive strain is revealed. These results are useful for understanding the effects of strain on the material properties of semiconductors and guiding the experiments to improve photovoltaic performance of Ge-based perovskites.

Influences of neoadjuvant chemotherapy on clinical indicators, prognosis and neutrophil/lymphocyte ratio of stage IB2-IIB cervical cancer

PURPOSE

To investigate the influence of neoadjuvant chemotherapy on the efficacy, clinical indicators, prognosis and neutrophil/lymphocyte ratio (NLR) of stage IB2-IIB cervical cancer.

METHODS

120 cervical cancer patients were selected and randomly divided into the control group (n=60) and the observation group (n=60). The patients in the observation group were treated with neoadjuvant chemotherapy combined with surgery, while those in the control group received treatment with surgery alone. The serum tumor markers [matrix metalloproteinase-9 (MMP-9), carcino-embryonic antigen (CEA) and cancer antigen 125 (CA-125)], immunoglobulins (Igs) (IgA and IgM), T-lymphocyte subsets [cluster of differentiation (CD) 4+, CD8+ and CD4+/CD8+], NLR, quality of life, change in cancer-related fatigue degree and clinical efficacy were compared before and after treatment between the two groups.

RESULTS

The levels of MMP-9, CEA, CA-125, NLR, IgA, IgM, CD4+ CD8+, CD4+/CD8+ and Cancer Fatigue Scale (CFS) were decreased, while the World Health Organization Quality of Life Scale Brief (WHOQOL-BREF) score was increased in both groups after treatment, and the observation group exhibited more apparent changes in those levels than the control group (p<0.05). The effective rate was higher, but the incidence rates of postoperative lymphatic metastasis, vascular invasion, parametrial invasion and positive margin were lower in the observation group than those in the control group (p<0.05). The observation group had longer survival time than the control group (p<0.05).

CONCLUSION

Neoadjuvant chemotherapy can effectively lower the levels of serum tumor markers and NLR, reduce the metastasis rate of cancer cells and the degree of cancer-related fatigue after operation, improve the quality of life and prolong the survival time.

A Novel Drug Delivery Carrier Comprised of Nimodipine Drug Solution and a Nanoemulsion: Preparation, Characterization, in vitro, and in vivo Studies

Purpose

Nimodipine (NIMO) is used clinically to treat ischemic damage resulting from subarachnoid hemorrhage. However, clinical application of NIMO is limited by poor aqueous solubility and low safety. To overcome these limitations, a novel two-vial NIMO-loaded nanoemulsion (NIMO-TNE) was designed in this study.

Methods

NIMO-TNE was prepared by mixing a nimodipine-polyethylene glycol 400 (NIMO-PEG400) solution and a commercially available 20% injectable blank nanoemulsion (BNE). Drug distribution in NIMO-TNE, physical stability, and dilution stability were evaluated in vitro, and pharmacokinetics and pharmacodynamics were evaluated in vivo. Safety was assessed using the hemolysis test and the intravenous irritation test, and acute toxicity of NIMO-TNE was compared with that of commercial Nimotop injection.

Results

Drug loading (DL) in NIMO-TNE was enhanced 5-fold compared with that in Nimotop injection. The mean particle size of NIMO-TNE was 241.53 ± 1.48 nm. NIMO-TNE and NIMO-TNE diluted in 5% glucose injection and 0.9% sodium chloride was stable for a sufficient duration to allow for clinical use. In addition, NIMO-TNE exhibited a similar pharmacokinetic profile and similar brain ischemia reduction in a rat middle cerebral artery occlusion (MCAO) model compared to Nimotop injection. Furthermore, NIMO-TNE did not induce hemolysis at 37°C, and NIMO-TNE induced less intravenous irritation than Nimotop injection. Moreover, NIMO-TNE could be injected at a 23-fold higher dose than the LD₅₀ of Nimotop injection with no obvious toxicity or side effects.

Conclusion

NIMO-TNE is a promising formulation suitable for intravenous injection, is easy to prepare, and exhibits excellent safety.

Anti-TGF-β attenuates tumor growth via polarization of tumor associated neutrophils towards an anti-tumor phenotype in colorectal cancer

Tumor associated neutrophils (TANs) play important roles in the progress of CRC. Since tumor microenvironments could influence the phenotypes of TANs, altering the tumor microenvironment to polarize the phenotype of TANs may be a new strategy for tumor treatment. This study aims to investigate the effect of anti-TGF-β on the polarization of TANs from a pro-tumor phenotype towards an anti-tumor phenotype in CRC. In this work, CRC patients had more infiltration of TANs and higher expression of TGF-β in CRC tissue when compared with the controls. In vitro, SW480 cells were co-cultured with primed neutrophils, which simulated the TANs in the tumor microenvironment, and TGF-β was blocked by anti-TGF-β (1D11) in order to polarize TANs. Anti-TGF-β treatment increased the cytotoxicity of TANs and decreased the metastatic chemoattractants secreted by TANs, and ultimately increased the apoptosis of CRC cells significantly while remarkably suppressing the migration of tumor cells. The changes of signaling pathways in the TANs and tumor cells were explored. The results showed that anti-TGF-β attenuated CRC may be partly mediated by suppression of PI3K/AKT signaling pathways in TANs and partly mediated by suppression of TGF-β/Smad signaling pathways in tumor cells. Furthermore, the tumor in the mice treated with 1D11 was obviously smaller and had reverse tumorigenesis compared with the controls, while neutrophil depletion reduced the anti-tumor effect of 1D11. Our data suggest that anti-TGF-β attenuates tumor growth via the polarization of TANs to an anti-tumor phenotype in CRC, which provides new strategies for CRC treatment.

Effect of the TetR family transcriptional regulator Sp1418 on the global metabolic network of Saccharopolyspora pogona

Background

Saccharopolyspora pogona is a prominent industrial strain due to its production of butenyl-spinosyn, a high-quality insecticide against a broad spectrum of insect pests. TetR family proteins are diverse in a tremendous number of microorganisms and some are been researched to have a key role in metabolic regulation. However, specific functions of TetR family proteins in S. pogona are yet to characterize.

Results

In the present study, the overexpression of the tetR-like gene sp1418 in S. pogona resulted in marked effects on vegetative growth, sporulation, butenyl-spinosyn biosynthesis, and oxidative stress. By using qRT-PCR analysis, mass spectrometry, enzyme activity detection, and sp1418 knockout verification, we showed that most of these effects could be attributed to the overexpression of Sp1418, which modulated enzymes related to the primary metabolism, oxidative stress and secondary metabolism, and thereby resulted in distinct growth characteristics and an unbalanced supply of precursor monomers for butenyl-spinosyn biosynthesis.

Conclusion

This study revealed the function of Sp1418 and enhanced the understanding of the metabolic network in S. pogona, and provided insights into the improvement of secondary metabolite production.

The draft genome of horseshoe crab Tachypleus tridentatus reveals its evolutionary scenario and well-developed innate immunity

BACKGROUND

Horseshoe crabs are ancient marine arthropods with a long evolutionary history extending back approximately 450 million years, which may benefit from their innate immune systems. However, the genetic mechanisms underlying their abilities of distinguishing and defending against invading microbes are still unclear.

RESULTS

Here, we describe the 2.06 Gbp genome assembly of Tachypleus tridentatus with 24,222 predicted protein-coding genes. Comparative genomics shows that T. tridentatus and the Atlantic horseshoe crab Limulus polyphemus have the most orthologues shared among two species, including genes involved in the immune-related JAK-STAT signalling pathway. Divergence time dating results show that the last common ancestor of Asian horseshoe crabs (including T. tridentatus and C. rotundicauda) and L. polyphemus appeared approximately 130 Mya (121-141), and the split of the two Asian horseshoe crabs was dated to approximately 63 Mya (57-69). Hox gene analysis suggests two clusters in both horseshoe crab assemblies. Surprisingly, selective analysis of immune-related gene families revealed the high expansion of conserved pattern recognition receptors. Genes involved in the IMD and JAK-STAT signal transduction pathways also exhibited a certain degree of expansion in both genomes. Intact coagulation cascade-related genes were present in the T. tridentatus genome with a higher number of coagulation factor genes. Moreover, most reported antibacterial peptides have been identified in T. tridentatus with their potentially effective antimicrobial sites.

CONCLUSIONS

The draft genome of T. tridentatus would provide important evidence for further clarifying the taxonomy and evolutionary relationship of Chelicerata. The expansion of conserved immune signalling pathway genes, coagulation factors and intact antimicrobial peptides in T. tridentatus constitutes its robust and effective innate immunity for self-defence in marine environments with an enormous number of invading pathogens and may affect the quality of the adaptive properties with regard to complicated marine environments.

Advances in nanomaterials for photodynamic therapy applications: Status and challenges

Photodynamic therapy (PDT), as a non-invasive therapeutic modality that is alternative to radiotherapy and chemotherapy, is extensively investigated for cancer treatments. Although conventional organic photosensitizers (PSs) are still widely used and have achieved great progresses in PDT, the disadvantages such as hydrophobicity, poor stability within PDT environment and low cell/tissue specificity largely limit their clinical applications. Consequently, nano-agents with promising physicochemical and optical properties have emerged as an attractive alternative to overcome these drawbacks of traditional PSs. Herein, the up-to-date advances in the fabrication and fascinating applications of various nanomaterials in PDT have been summarized, including various types of nanoparticles, carbon-based nanomaterials, and two-dimensional nanomaterials, etc. In addition, the current challenges for the clinical use of PDT, and the corresponding strategies to address these issues, as well as future perspectives on further improvement of PDT have also been discussed.

[The curative effect of manual reduction combined with vestibular rehabilitation exercise in the treatment of benign paroxysmal positional vertigo]

Objective:To investigate the effect of vestibular rehabilitation exercise combined with manual reduction in the treatment of benign paroxysmal positional vertigo（BPPV）. Method:A total of 186 patients with benign paroxysmal positional vertigo were selected and randomly divided into experimental group and control group . The control group was treated with manual reduction, while the experimental group was treated with manual reduction combined with vestibular rehabilitation exercises. Patients with posterior semicircular canal BPPV carried out Brandt-Daroff exercises, while patients with horizontal semicircular canal BPPV carried out Cawthorne-Cooksey exercises and position restriction. To analyze the clinical curative effect, DHI score, residual dizziness and recurrence of the two groups. Result:There was no significant difference in total efficiency rate and DHI score between the two groups at the first diagnosis（P>0.05）. After 1 week, 2 weeks and 1 month of follow-up, the total efficiency rate of the experimental group were 90.3%, 91.4% and 93.5% respectively, which were significantly higher than those of the control group（P<0.05）. Synchronously, the scores of DHI in experimental group were respectively 14.33±5.71, 12.25±4.98 and 9.45±3.70, which were significantly lower than the control group（P<0.05）. For the experimental group, in the first diagnosis, 1 week, 2 weeks and 1 month after follow-up, residual dizziness patients were 29 cases, 13 cases, 8 cases and 0 cases. The mean duration of residual dizziness was （5.86±4.71） days, which was significantly lower than that in the control group（P<0.05）. One month after follow-up, the recurrence of patients in the experimental group were 5 cases, while the control group were 11 cases, significant difference between the two groups（χ²=4.704, P=0.030）. Conclusion:Manual reduction combined with vestibular rehabilitation exercise can significantly improve the therapeutic effect of BPPV, ameliorate the residual dizziness symptoms and reduce the recurrence rate, meanwhile improve the balance function and quality life of patients.

Detection of cyprinid herpesvirus 2 by loop-mediated isothermal amplification in combination with a lateral flow dipstick

We developed a convenient technique to detect Herpesviral haematopoietic necrosis attributed to cyprinid herpes virus 2 (CyHV-2), a serious disease of Crucian carp and goldfish related to high mortality. In the present study, we employed a lateral flow dipstick (LAMP-LFD) to present a loop-mediated isothermal amplification assay. The specificity was ascertained via other six viruses, and the sensitivity was compared using PCR method, which are the reaction conditions changes for the method improved. The results revealed that CyHV-2 performance was observable at 64 °C in a separated tube within 60 min, when the samples hybridized using an FITC-labeled probe. As the LAMP-LFD method's specificity was high, with its sensitivity identical to that of traditional PCR, the overall DNA collected revealed the lowest detection limit of 0.18 pg/μl from goldfish diseased by CyHV-2. In summary, the development of LAMP-LFD's method does not require expensive instruments, and it can be regarded as a fast, simple, and reliable method for CyHV-2 detection.

Two-Dimensional Borophene: Properties, Fabrication, and Promising Applications

Monoelemental two-dimensional (2D) materials (Xenes) aroused a tremendous attention in 2D science owing to their unique properties and extensive applications. Borophene, one emerging and typical Xene, has been regarded as a promising agent for energy, sensor, and biomedical applications. However, the production of borophene is still a challenge because bulk boron has rather intricate spatial structures and multiple chemical properties. In this review, we describe its excellent properties including the optical, electronic, metallic, semiconducting, photoacoustic, and photothermal properties. The fabrication methods of borophene are also presented including the bottom-up fabrication and the top-down fabrication. In the end, the challenges of borophene in the latest applications are presented and perspectives are discussed.

LvPPAE2 induced by WSV056 confers host defense against WSSV in Litopenaeus vannamei

Viral immediate early (IE) genes encode regulatory proteins that are critical for viral replication. WSV056 is an IE protein of white spot syndrome virus (WSSV), an important pathogen of farmed shrimp. It targets the host Rb protein(s) and, according to a previous study, may enhance the replication of the viral genome. However, the ectopic expression of WSV056 in transgenic Drosophila melanogaster exerted an inhibitory effect on the replication of Drosophila C virus (DCV). Transcriptome study using Affymetrix GeneChip suggested that the enrichment of serine proteases (SPs) likely accounts for DCV inhibition in WSV056-overexpressing Drosophila. Injection of recombinant WSV056 to the WSSV natural host Litopenaeus vannamei enhanced the expression of the SP family member prophenoloxidase-activating enzyme 2 (LvPPAE2) and conferred shrimp with more resistance to WSSV infection. LvPPAE2 knockdown contributed to decreased expression of antimicrobial peptides LvAlf1 and LvLyz1, reduced hemolymph phenoloxidase activity, and increased virus load, suggesting that LvPPAE2 is involved in the host defense against WSSV infection. Taken together, these results suggest that wsv056 plays a role in restricting viral replication by inducing the SP-mediated immune responses in the host.

A first-principles study on the optoelectronic properties of mixed-halide double perovskites Cs2TiI6−xBrx

All-inorganic double perovskites as promising photovoltaic materials have received great attention in recent years.

[Short-term outcomes of minimally invasive reoperation for tricuspid regurgitation after left-sided valve surgery]

Objective: To examine the short-term outcomes of minimally invasive reoperation for severe tricuspid regurgitation after left-sided valve surgery. Methods: From January 2015 to December 2018, a total of 89 patients with severe tricuspid regurgitation after left-sided valve surgery received reoperation in Department of Cardiovascular Surgery, Zhongshan Hospital, Fudan University were included in this study. There were 21 males and 68 females, aging of (56.4±7.9) years (range: 41 to 74 years). The interval between previous left-sided valve surgery and tricuspid reoperation was (14.1±6.1) years (range: 4 to 33 years). A combination of multiple minimally invasive techniques were adopted, including endoscopy-assist right minithoracotomy approach, peripheral cannulation strategy with the vacuum-assist single venous drainage technique, heart beating technique, and temporary percutaneous pacemaker implantation, with a concomitant enhancement in preoperative right cardiac function optimization. Results: All patients received minimally invasive isolated tricuspid valve replacement (n=81) or tricuspid valve repair (n=8). After the application of multiple minimally invasive techniques, the operative mortality rate was only 3.4% (3/89). The causes of death were progressive right heart failure with multiorgan failure (n=1) and low cardiac output associated with postoperative bleeding (n=2). Regarding to the perioperative complications, renal replacement therapy rate was 5.6% (5/89), permanent pacemaker implantation rate was 1.1% (1/89), and the incidence of stroke was 0. Mechanical ventilation time was 24(24) hours, ICU stay time was 2.5 (3.0) days (M(Q(R))). During the short-term follow-up, there were no case of severe tricuspid regurgitation, 2 cases of moderate regurgitation, 4 cases of mild-to-moderate regurgitation. Conclusions: For severe tricuspid regurgitation after left-sided valve surgery, the advanced minimally invasive techniques can significantly reduce the operative mortality and morbidity. Minimally invasive bioprosthetic tricuspid valve replacement is a reliable alternative for severe tricuspid regurgitation after left-sided valve surgery.

[Clinical application of vertebral arch-transverse pathway in pedicle screw implantation]

Objective

To investigate the safety and effectiveness of pedicle screw implantation via vertebral arch-transverse pathway in clinical application by a prospective randomized controlled trial.

Methods

Twenty-four patients who were admitted between May 2015 and June 2017 and met the selection criteria for thoracic pedicle screw fixation were included in the study. According to the random number table method, they were divided into the trial group (screw implantation via vertebral arch-transverse pathway) and the control group (traditional screw implantation technology), with 12 patients in each group. There was no significant difference between the two groups in age, gender, cause of injury, injured segment, and the interval between injury and operation (P>0.05). The time of screw implantation was recorded and compared between the two groups. The acceptable rate of screw implantation and the penetration rate of pedicle wall were calculated after operation.

Results

The time of screw implantation of trial group was (5.08±1.74) minutes, which was significantly shorter than that of control group [(5.92±1.66) minutes], and the difference was significant (t=4.258, P=0.023). Patients in both groups were followed up 1-2 years, with an average of 1.5 years. During the follow-up, no failure of internal fixation occurred. At 1 week after operation, the screw implantation in trial group was rated as gradeⅠin 54 screws, gradeⅡ in 3 screws, and grade Ⅲ in 2 screws, with the acceptable rate of 93.61%. The screw implantation in control group was rated as gradeⅠin 40 screws, grade Ⅱin 10 screws, grade Ⅲ in 8 screws, and grade Ⅳ in 1 screw, with the acceptable rate of 84.75%. There was significant difference in the acceptable rate of screw implantation between the two groups (χ²=3.875, P=0.037). The penetration rate of pedicle wall in trial group was 8.47% (5/59), which was significantly lower than that in the control group [32.20% (19/59); χ²=4.125, P=0.021].

Conclusion

Compared with the traditional technique, the pedicle screw implantation via vertebral arch-transverse pathway can obtain a good position of the screw canal with higher accuracy and simpler operation.

Alantolactone suppresses human osteosarcoma through the PI3K/AKT signaling pathway

Osteosarcoma is the most common type of malignant bone cancer and results in cancer-related deaths among adolescents. Alantolactone (ALT) demonstrates antitumor properties in various diseases; however, its potential role in osteosarcoma is relatively unclear. The aim of the present study was to evaluate the effect of ALT on osteosarcoma. ALT significantly decreased the viability of U2OS and HOS osteosarcoma cell lines. Cells flow cytometry assay and Hoechst 33258 staining assay revealed that ALT significantly increased the proportion of apoptotic U2OS cells. In addition, wound healing and Transwell invasion assays demonstrated that the invasion and migration of osteosarcoma were markedly reduced upon ALT treatment. It was hypothesized that the antitumor functions of ALT are mediated through inhibition of the PI3K/AKT signaling pathway. In conclusion, the results of the present study confirmed the inhibition of ALT on osteosarcoma cells via downregulation of PI3K/AKT signaling pathways, suggesting ALT as a potential therapeutic candidate for osteosarcoma.

MRT, Functioning with NURF Complex, Regulates Lipid Droplet Size

Lipid droplets (LDs) are highly dynamic organelles that store neutral lipids. Through a gene overexpression screen in the Drosophila larval fat body, we have identified that MRT, an Myb/switching-defective protein 3 (Swi3), Adaptor 2 (Ada2), Nuclear receptor co-repressor (N-CoR), Transcription factor (TF)IIIB (SANT)-like DNA-binding domain-containing protein, regulates LD size and lipid storage. MRT directly interacts with, and is functionally dependent on, the PZG and NURF chromatin-remodeling complex components. MRT binds to the promoter of plin1, the gene encoding the LD-resident protein perilipin, and inhibits the transcription of plin1. In vitro LD coalescence assays suggest that mrt overexpression or loss of plin1 function facilitates LD coalescence. Our findings suggest that MRT functions together with chromatin-remodeling factors to regulate LD size, likely through the transcriptional repression of plin1.

[Surgical treatment for tricuspid regurgitation after left-sided valve surgery]

Late tricuspid regurgitation after left-sided valve surgery can negatively affect long-term prognosis. The surgical timing and strategy of tricuspid valve reoperation will have important impact on the surgical outcomes. However, there is no clear recommendations of the surgical timing for this condition in the current guidelines. Generally, tricuspid valve reoperation should be performed before irreversible right heart failure occurs. Although tricuspid valve repair is the first choice for tricuspid regurgitation, bioprosthetic tricuspid valve replacement might be a reliable alternative when tricuspid leaflets have severe rheumatic damage or right ventricle and tricuspid annulus significantly dilate. Combined minimally invasive surgical techniques, including right minithoracotomy approach, accessing the right atrium directly through the pericardium with limited dissection, peripheral cannulation strategy with the vacuum-assist single venous drainage technique and heart beating technique, can significantly decrease the operative mortality and postoperative bleeding. With development of interventional therapy, transcatheter tricuspid valve repair or replacement may become alternatives for tricuspid regurgitation after left-sided valve surgery in the future.