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Mountain biodiversity is of great importance to biogeography and ecology. However, it is unclear what ecological and evolutionary processes best explain the generation and maintenance of its high levels of species diversity. In this study, we determined which of six common hypotheses (e.g., climate hypotheses, habitat heterogeneity hypothesis and island biogeography theory) best explain global patterns of species diversity in Rhododendron. We found that Rhododendron diversity patterns were most strongly explained by proxies of island biogeography theory (i.e., mountain area) and habitat heterogeneity (i.e., elevation range). When we examined other relationships important to island biogeography theory, we found that the planimetric area and the volume of mountains were positively correlated with the Rhododendron diversity, whereas the ‘mountains-to-mainland’ distance was negatively correlated with Rhododendron diversity and shared species. Our findings demonstrate that Rhododendron diversity can be explained by island biogeography theory and habitat heterogeneity, and mountains can be regarded as islands which supported island biogeography theory.

Abstract Vitamin D deficiency is increasingly common in systemic lupus erythematosus (SLE) patients and is associated with the disease activity and proteinuria. Recently, alterations in metabolism have been recognized as key regulators of SLE pathogenesis. Our objective was to identify differential metabolites in the serum metabolome of SLE with vitamin D deficiency. In this study, serum samples from 31 SLE patients were collected. Levels of 25(OH)D3 were assayed by ELISA. Patients were divided into two groups according to their vitamin D level (20 ng/ml). Untargeted metabolomics were used to study the metabolite profiles in serum by high-performance liquid chromatography-tandem mass spectrometry. Subsequently, we performed metabolomics profiling analysis to identify 52 significantly altered metabolites in vitamin D deficient SLE patients. The area under the curve (AUC) from ROC analyses was calculated to assess the diagnostic potential of each candidate metabolite biomarker. Lipids accounted for 66.67% of the differential metabolites in the serum, highlighted the disruption of lipid metabolism. The 52 differential metabolites were mapped to 27 metabolic pathways, with fat digestion and absorption, as well as lipid metabolism, emerging as the most significant pathways. The AUC of (S)-Oleuropeic acid and 2-Hydroxylinolenic acid during ROC analysis were 0.867 and 0.833, respectively, indicating their promising diagnostic potential. In conclusion, our results revealed vitamin D deficiency alters SLE metabolome, impacting lipid metabolism, and thrown insights into the pathogenesis and diagnosis of SLE.

Introduction China is the largest tobacco consumer in the world, and tobacco poses a serious threat to the health of pregnant women. However, there are relatively few domestic studies on smoking during pregnancy and childbirth outcomes among pregnant women. The purpose of this study was to analyze the effect of active and passive smoking on pregnant women and their pregnancy outcomes, providing evidence and recommendations for intervention measures. Methods This was a cohort study in Shanghai from April 2021 to September 2023. According to the smoking status of pregnant women, they were divided into three groups: active smokers, passive smokers and non-smokers. A self-designed questionnaire was utilized to conduct the survey, and their pregnancy outcomes were tracked and followed up. Results A total of 3446 pregnant women were included in this study, among which 2.1% were active smokers, 43.5% were passive smokers, and 54.4% were nonsmokers. The average age of the pregnant women was 29.9 years, and 41.2% had a university degree or higher. The education level of active smokers and passive smokers was significantly lower than that of non-smokers (p

Fat content is an important trait in pig production. Adipose tissue and muscle are important sites for fat deposition and affect production efficiency and quality. To regulate the fat content in these tissues, we need to understand the mechanisms behind fat deposition. Laiwu pigs, a Chinese indigenous breed, have significantly higher fat content in both adipose tissue and muscle than commercial breeds such as Duroc. In this study, we analyzed the transcriptomes in adipose tissue and muscle of 21-d-old Laiwu and Duroc piglets. Results showed that there were 828 and 671 differentially expressed genes (DEG) in subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT), respectively. Functional enrichment analysis showed that these DEG were enriched in metabolic pathways, especially carbohydrate and lipid metabolism. Additionally, in the longissimus muscle (LM) and psoas muscle (PM), 312 and 335 DEG were identified, demonstrating enrichment in the cell cycle and metabolic pathways. The protein–protein interaction (PPI) networks of these DEG were analyzed and potential hub genes were identified, such as FBP1 and SCD in adipose tissues and RRM2 and GADL1 in muscles. Meanwhile, results showed that there were common DEG between adipose tissue and muscle, such as LDHB, THRSP, and DGAT2. These findings showed that there are significant differences in the transcriptomes of the adipose tissue and muscle between Laiwu and Duroc piglets (P

ABSTRACT: Objectives: The dissemination of New Delhi metallo-β-lactamase-5 (NDM-5) among various species of Enterobacterales has attracted serious global attention. Here, we characterise the genomic characterisation of blaNDM-5-IncX3 plasmid (pNDM-KA3) in an ST4 Klebsiella aerogenes (KA3) strain isolated from a neonate with pneumonia. Methods: Antimicrobial susceptibility and multilocus sequence typing was performed for the KA3. The plasmid conjugation assay and plasmid stability of the KA3 (pNDM-KA3) were also analysed. The pNDM-KA3 plasmid was further analysed by whole-genome sequencing and comparative analysis to determine the genetic environment of blaNDM-5. Results: The KA3 strain belongs to ST4 and shows high resistance to β-lactam antibiotics, including carbapenems, but is susceptible to ciprofloxacin, amikacin, tigecycline, and colistin. The pNDM-KA3 was successfully transferred to the recipient E. coli J53 and showed strong stability in K. aerogenes. Genomic sequencing revealed that the pNDM-KA3 plasmid was assigned to plasmid incompatibility group X3 with 43367 bp, and a conserved structure sequence of △IS3000-△ISAba125-IS5-blaNDM-5-bleMBL- trpF-dsbC-IS26 was detected upstream and downstream of the blaNDM-5 gene. Further analysis revealed that insertion sequences mediated the dissemination of blaNDM-5 from other species of Enterobacterales. The pNDM-KA3 showed high similarity to blaNDM-5-harbouring plasmids in other species of Enterobacterales, with these plasmids carrying genes for replication (repB), partitioning (parA and parB), stability (hns), and conjugative transfer (virB and virD). Conclusions: Continued monitoring for the dissemination of blaNDM-5 among uncommon Enterobacterales species should be further reinforced.

Abstract Background Styrax tonkinensis (Pierre) Craib ex Hartwich faces challenges in expanding in the south provinces of Yangtze River region due to climate extremes like flood-drought abrupt alternation (FDAA) caused by global warming. Low tolerance to waterlogging and drought restricts its growth in this area. To study its antioxidant system and molecular response related to the peroxisome pathway under FDAA, we conducted experiments on two-year-old seedlings, measuring growth indexes, reactive oxygen species content, antioxidant enzyme activity, and analyzing transcriptomes under FDAA and drought (DT) conditions. Results The physiological results indicated a reduction in water content in roots, stems, and leaves under FDAA conditions. The most significant water loss, amounting to 15.53% was observed in the leaves. Also, ROS accumulation was predominantly observed in leaves rather than roots. Through transcriptome analysis, we assembled a total of 1,111,088 unigenes (with a total length of 1,111,628,179 bp). Generally, SOD1 and CAT genes in S. tonkinensis seedlings were up-regulated to scavenge ROS. Conversely, the MPV17 gene exhibited contrasting reaction with up-regulation in leaves and down-regulation in roots, leading to increased ROS accumulation in leaves. CHS and F3H were down-regulated, which did not play an essential role in scavenging ROS. Moreover, the down-regulation of PYL, CPK and CALM genes in leaves may not contribute to stomatal closure, thereby causing continuous water loss through transpiration. Whereas, the decreased root vigor during the waterlogging phase and up-regulated CPK and CALM in roots posed obstacles to water absorption by roots. Additionally, the DEGs related to energy metabolism, including LHCA and LHCB, were negatively regulated. Conclusions The ROS generation triggered by MPV17 genes was not the main reason for the eventual mortality of the plant. Instead, plant mortality may be attributed to water loss during the waterlogging phase, decreased root water uptake capacity, and continued water loss during the subsequent drought period. This study establishes a scientific foundation for comprehending the morphological, physiological, and molecular facts of S. tonkinensis under FDAA conditions.

Patterns of taxonomic and phylogenetic beta diversity and their relationships with environmental correlates can help reveal the origin and evolutionary history of regional biota. The Qinghai-Tibet Plateau (QTP) harbors an exceptionally diverse flora, however, a phylogenetic perspective has rarely been used to investigate its beta diversity and floristic regions. In this study, we used a phylogenetic approach to identify patterns of beta diversity and quantitatively delimit floristic regions on the Qinghai-Tibet Plateau. We also examined the relationships between multifaceted beta diversity, geographical distance, and climatic difference, and evaluated the relative importance of various factors (i.e., climate, topography and history) in shaping patterns of beta diversity. Sørensen dissimilarity indices indicated that patterns of species turnover among sites dominated the QTP. We also found that patterns of both taxonomic and phylogenetic beta diversity were significantly related to geographical distance and climatic difference. The environmental factors that contributed most to these patterns of beta diversity include annual precipitation, mean annual temperature, climatic gradients and climatic instability. Hierarchical dendrograms of dissimilarity and non-metric multidimensional scaling ordination based on phylogenetic beta diversity data identified ten floristic subregions in the QTP. Our results suggest that the contemporary environment and historical climate changes have filtered species composition among sites and eventually determined beta diversity patterns of plants in the QTP.

Abstract Background Rheumatoid arthritis (RA) is a major public health problem. Unfortunately, there is a scarcity of comprehensive and up-to-date information regarding the burden of RA and its dynamic trends in subsequent years. To examine the changing trends in the global burden of RA and forecast for 2044, which will facilitate the development of strategies tailored to RA burden and provide reference for the development of effective treatment guidelines. Methods Following the general analytical strategy used the Global Burden of Disease Study (GBD) 2019, which included 204 countries, the age-standardized incidence rate (ASIR), age-standardized mortality rate (ASMR) and age-standardized disability adjusted of life year (DALY) rate for RA were analyzed. Results The ASIR, ASMR and age-standardized DALY rate for RA in 2019 were 13.001/100,000 (95% UI, 11.833 ~ 14.274), 0.574/100,000 (95% UI, 0.356 ~ 0.793) and 39.565/100,000 (95% UI, 49.529 ~ 30.508), respectively. America had the highest ASIR [18.578(95% UI, 17.147 ~ 20.148)] and age-standardized DALY rate [53.676(95% UI, 40.106 ~ 67.968)] in 2019. Asia had the highest ASMR [0.681(95% UI, 0.802 ~ 0.480)] in 2019. From 1990 to 2019, a significant average annual percentage change (AAPC) in the ASIR was observed in both males [0.237% (95% CI, 0.216 ~ 0.259%)] and females [0.197% (95% CI, 0.141 ~ 0.254%)], AAPC in the ASMR was observed in both males [-0.398% (95% CI, -0.605~-0.191%)] and females [-0.295% (95% CI, -0.424~-0.65%)]. Age effects indicated that the relative risk (RR) of RA-associated incidence and mortality rates increased with age among males and females. The RR of RA increased over time and started to gradually increase from 1990. Cohort effects showed decreases in incidence, mortality and DALY rates in successive birth cohorts. The global incidence of RA would continue to increase in the future, while mortality would continue to decrease. Conclusion The increased risk of RA is dominantly influenced by age effects and period effects and the ethnic area. The results suggest that early identification and treatment of RA is important for reducing the ongoing burden with age, and targeted health education and specific intervention programs should be promoted to control middle-elderly population.

AbstractPurpose Exosomal miRNAs play key roles in various biological processes such as cell proliferation, angiogenesis, migration and invasion. We explored whether exosomal miRNAs can promote local recurrence (LR) of lung tumors following incomplete microwave ablation (MWA) therapy.Methods Exosomal miRNA profiles before and after incomplete MWA in lung cancer (LC) patients with LR (n = 3) were sequenced and compared. The differentially expressed miRNAs of interest were validated in clinical samples (n = 10) and MWA-treated cells using RT-qPCR analysis. Target genes of the miRNAs were predicted and validated. The biological functions of miRNAs in proliferation, angiogenesis and metastasis of A549 cells were evaluated in vitro and in vivo.Results A total of 270 miRNAs (243 upregulated and 27 downregulated) were differentially expressed after incomplete MWA in patients with local recurrence. Upregulation of miR-133a-3p after MWA was validated in the cells and clinical samples. Cell functional experiments suggested that miR-133a-3p overexpression derived from serum exosomes increased cell viability, migration and invasion ability, tube formation activity and proliferation of A549 cells. Sirtuin 1 (SIRT1) was identified as a target gene for miR-133a-3p. Moreover, miR-133a-3p delivered by exosomes significantly promoted tumor growth, paralleled by reduced SIRT1 expression in a subcutaneous tumorigenesis animal model and increased the number of lung nodules by tail vein metastasis in vivo.Conclusion Exosomal miR-133a-3p overexpression promoted tumor growth and metastasis following MWA and could be a promising biomarker for LC recurrence after incomplete MWA.

IntroductionAdenoid hypertrophy (AH) is a common upper respiratory disorder in children. Disturbances of gut microbiota have been implicated in AH. However, the interplay of alteration of gut microbiome and enlarged adenoids remains elusive.Methods119 AH children and 100 healthy controls were recruited, and microbiome profiling of fecal samples in participants was performed using 16S rRNA gene sequencing. Fecal microbiome transplantation (FMT) was conducted to verify the effects of gut microbiota on immune response in mice.ResultsIn AH individuals, only a slight decrease of diversity in bacterial community was found, while significant changes of microbial composition were observed between these two groups. Compared with HCs, decreased abundances of Akkermansia, Oscillospiraceae and Eubacterium coprostanoligenes genera and increased abundances of Bacteroides, Faecalibacterium, Ruminococcus gnavus genera were revealed in AH patients. The abundance of Bacteroides remained stable with age in AH children. Notably, a microbial marker panel of 8 OTUs were identified, which discriminated AH from HC individuals with an area under the curve (AUC) of 0.9851 in the discovery set, and verified in the geographically different validation set, achieving an AUC of 0.9782. Furthermore, transfer of mice with fecal microbiota from AH patients dramatically reduced the proportion of Treg subsets within peripheral blood and nasal-associated lymphoid tissue (NALT) and promoted the expansion of Th2 cells in NALT.ConclusionThese findings highlight the effect of the altered gut microbiota in the AH pathogenesis.

ObjectiveWe investigated the epidemiological surveillance of the intestinal colonization and nosocomial infection of carbapenem-resistant Enterobacteriales (CRE) isolates from inpatients, which can provide the basis for developing effective prevention.MethodsA total of 96 CRE strains were collected from 1,487 fecal samples of hospitalized children between January 2016 and June 2017, which were defined as the “CRE colonization” group. In total, 70 CRE clinical isolates were also randomly selected for the comparison analysis and defined as the “CRE infection” group. The antimicrobial susceptibility of all strains was determined by the microdilution broth method. Polymerase chain reaction (PCR) was used to analyze carbapenemase genes, plasmid typing, and integrons. Multilocus sequence typing was further used to determine clonal relatedness.ResultsIn the “CRE colonization” group, Klebsiella pneumoniae was mostly detected with a rate of 42.7% (41/96), followed by Escherichia coli (34.4%, 33/96) and Enterobacter cloacae (15.6%, 15/96). The ST11 KPC-2 producer, ST8 NDM-5 producer, and ST45 NDM-1 producer were commonly present in carbapenem-resistant K. pneumoniae (CRKPN), carbapenem-resistant E. coli (CRECO), and carbapenem-resistant E. cloacae (CRECL) isolates, respectively. In the “CRE infection” group, 70% (49/70) of strains were K. pneumoniae, with 21.4% E. cloacae (15/70) and 5.7% E. coli (4/70). The ST15 OXA-232 producer and ST48 NDM-5 producer were frequently observed in CRKPN isolates, while the majority of NDM-1-producing CRECL isolates were assigned as ST45. Phylogenetic analysis showed that partial CRE isolates from intestinal colonization and nosocomial infection were closely related, especially for ST11 KPC-2-producing CRKPN and ST45 NDM-1-producing CRECL. Furthermore, plasmid typing demonstrated that IncF and IncFIB were the most prevalent plasmids in KPC-2 producers, while IncX3/IncX2 and ColE were widely spread in NDM producer and OXA-232 producer, respectively. Then, class 1 integron intergrase intI1 was positive in 74.0% (71/96) of the “CRE colonization” group and 52.9% (37/70) of the “CRE infection” group.ConclusionThis study revealed that CRE strains from intestinal colonization and nosocomial infection showed a partial correlation in the prevalence of CRE, especially for ST11 KPC-2-producing CRKPN and ST45 NDM-1-producing CRECL. Therefore, before admission, long-term active screening of rectal colonization of CRE isolates should be emphasized.

Approximately 12% of China’s papermaking raw materials are derived from wood, while the majority are sourced from branches. Styrax tonkinensis is a more desirable species for pulpwood in subtropical ultra-short rotations, whose branches are prone to breakage. Lignin has a significant impact on wood quality and pulping yield, and the growth process influences lignin biosynthesis. To explore the lignin biosynthesis pathway in S. tonkinensis, we determined the lignin content in the current-year and biennial branches on 20 July, 20 September, and 20 October and analyzed the transcriptome sequencing results. It was concluded that the lignin content showed an increasing trend in the current-year branches (182.26, 206.17, and 213.47 mg/g, respectively), while that in the biennial branches showed a decrease in the samples taken in October, without significant difference (221.77, 264.43, and 261.83 mg/g, respectively). The transcriptome sequencing results showed that 91,513 unigenes were spliced with a total length of 92,961,618 bp. KEGG pathway analysis indicated that the upregulated DEGs were mainly enriched in the phenylpropanoid biosynthesis pathway. Our study suggested that CCoAOMT, COMT, peroxidase, and F5H may serve as key enzymes regulating lignin synthesis in branches of S. tonkinensis, thereby influencing the lignin content.

Salinity is a serious environmental problem following a worsening trend. This study investigates the role of 24-epibrassinolide(EBR) in regulating plant growth and physiological performances, particularly in alleviating the negative effects of salt stress. Melia azedarach L. seedlings from two seed sources, Sheyang (SY) and Xiashu (XS), were exposed to sea salt and treated with different concentrations of EBR within a 60-day period. The results demonstrate that appropriate EBR application improved the seedlings’ stress tolerance by promoting growth and physiological systems. In terms of the relative increment, it showed that a difference of 1.45% and 1.13% in the SY and XS groups was the positive effect of the highest EBR treatment concentration. As for diameter growth, the difference observed was 2.51% and 1.80% for the SY and XS groups, respectively. In all physiological measurements, including the content of photosynthetic pigments, water relations, membrane stability, osmolytes and antioxidant enzymes, significant changes generally observed between salt stress alone and the highest EBR treatment concentration. A better performance was observed in the SY seed source, which is of a coastal nature. These findings contribute to our understanding of Melia azedarach’s adaptation to changing environments and provide potential for further molecular studies as well as valuable insights for forestry, agricultural and ecological research.

Floral scent (FS) plays a crucial role in the ecological functions and industrial applications of plants. However, the physiological and metabolic mechanisms underlying FS formation remain inadequately explored. Our investigation focused on elucidating the differential formation mechanisms of 2-phenylethanol (2-PE) and benzyl alcohol (BA) by examining seven related enzyme concentrations and the content of soluble sugar, soluble proteins, carbon (C) and nitrogen (N), as well as the C/N ratio. The findings revealed that the peak content of 2-PE in M. ‘Praire Rose’ and BA in M. ‘Lollipop’ occurred during the end flowering stage (S4) and flowering stage (S3) periods, respectively. The enzyme concentration change trends of phenylpyruvate decarboxylase (PDL), phenylacetaldehyde reductase (PAR), soluble protein, C, N, and C/N ratio changes during the S3-S4 period in M. ‘Praire Rose’ and M. ‘Lollipop’ were entirely opposite. Correlation and PCA analysis demonstrated that the content of CYP79D73 (a P450) and N, and the C/N ratio were key factors in 2-PE production in M. ‘Praire Rose’. The production of BA in M. ‘Lollipop’ was more influenced by the content of phenylacetaldehyde synthase (PAAS), CYP79D73, and soluble sugar. As CYP79D73 exits oppositely in correlation to 2-PE (M. ‘Praire Rose’) and BA (M. ‘Lollipop’), it is hypothesized that CYP79D73 was postulated as the primary factor contributing to the observed differences of 2-PE (M. ‘Praire Rose’) and BA (M. ‘Lollipop’) formation. These results carry significant implications for crabapple aromatic flower breeding and the essential oil industry etc.

Combining the application of nitrogen and phosphorus is widely recognized as an effective measure to promote seedling growth. The purpose of this study was to investigate the effects of the combined application of nitrogen and phosphorus on the growth and nutrient status of C. camphora container seedlings. Exponential fertilization was applied to a range of fertilizers, including single nitrogen fertilizer, single phosphorus fertilizer, and combinations of nitrogen and phosphorus to C. camphora. Eight distinct fertilization levels of treatment (CK, N1, N2, N3, P, N1P, N2P, and N3P) were established. The height and ground diameter of the seedlings were determined periodically in each treatment group. Biomass, root system (including root length, root surface area, and root volume), and nutrient accumulation (content of soluble sugars, soluble proteins, and starch in the root system, stems, and leaves) were determined for each treatment group of seedlings. The N3P treatment (N: 9000 mg∙plant−1 + P: 6000 mg∙plant−1) had the most significant effect on the height and ground diameter of C. camphora container seedlings, while the N3 treatment (N: 9000 mg∙plant−1) proved to be the most beneficial for biomass accumulation among the eight different fertilizer levels. In addition, a single P fertilizer (P: 6000 mg∙plant−1) emerged as the most effective fertilizer for enhancing root morphology (root length, root surface area, root volume, and root average diameter) and accumulating nutrient composition (soluble sugar, soluble protein, and starch). Furthermore, it was discovered that a high level of nitrogen fertilization hindered the accumulation of nutrient composition in C. camphora container seedlings. Our comprehensive analysis revealed that nitrogen fertilizer promoted the morphological growth of C. camphora container seedlings, while phosphorus fertilizer proved to be the most beneficial for root growth and nutrient composition accumulation. Additionally, it was emphasized that controlling the quantity of nitrogen fertilizer is also a crucial measure.

In star clusters, close stellar encounters can strongly impact the architecture of a planetary system or even destroy it. We present a systematic study of the effects of stellar flybys on two-planet systems. When such a system experiences flybys, one or both planets can be ejected, forming free-floating planets (FFPs), captured planets (CPs) around the flyby star, and free-floating binary planets (BPs); the remaining single-surviving planets (SSPs) can have their orbital radii and eccentricities greatly changed. Through numerical experiments, we calculate the formation fractions (or branching ratios) of FFPs, SSPs, CPs, and BPs as a function of the pericenter distance of the flyby, and use them to derive analytical expressions for the formation rates of FFPs, SSPs, CPs and BPs in general cluster environments. We find that the production rates of FFPs and SSPs are similar (for the initial planet semimajor axis ratio a _1 / a _2 = 0.6–0.8), while the rate for CPs is a few times smaller. The formation fraction of BPs depends strongly on a _1 / a _2 and on the planet masses. For Jupiter-mass planets, the formation fraction of BPs is always less than 1% (for a _1 / a _2 = 0.8) and typically much smaller (≲0.2% for a _1 / a _2 ≲ 0.7). The fraction remains less than 1% when considering 4 M _J planets. Overall, when averaging over all flybys, the production rate of BPs is less than 0.1% of that of FFPs. We also derive the velocity distribution of FFPs produced by stellar flybys, and the orbital parameter distributions of SSPs, CPs, and BPs. These results can be used in future studies of exotic planets (including FFPs) and planetary systems.

AimThis study aims to quantitatively analyze the changes in local microcirculation in early osteonecrosis of the femoral head (ONFH) by dynamic contrast-enhanced (DCE) MRI and to explore the pathophysiological mechanisms of early ONFH.Patients and MethodsWe selected 49 patients (98 hips) aged 21–59 years who were clinically diagnosed with early ONFH. A total of 77 femoral heads were diagnosed with different degrees of necrosis according to the Association Research Circulation Osseous (ARCO) staging system, and 21 femoral heads were judged to be completely healthy. All patients underwent DCE-MRI scanning. Pseudocolor images and time-signal intensity curves were generated by Tissue 4D processing software. The volume transfer constant (Ktrans), extracellular extravascular space, also known as vascular leakage (Ve), and transfer rate constant (Kep) of healthy and different areas of necrotic femoral heads were measured on perfusion parameter maps. The differences and characteristics of these parameters in healthy and different areas of necrotic femoral heads were analyzed.ResultsThe signal accumulation in healthy femoral heads is lower than that of necrotic femoral heads in pseudocolor images. The time-signal intensity curve of healthy femoral heads is along the horizontal direction, while they all have upward trends for different areas of necrotic femoral heads. The mean value of Ktrans of healthy femoral heads was lower than the integration of necrotic, boundary, and other areas (F = 3.133, P = .036). The Kep value of healthy femoral heads was higher than the integration of lesion areas (F = 6.273, P = .001). The mean Ve value of healthy femoral heads was smaller than that of the lesion areas (F = 3.872, P = .016). The comparisons of parameters between different areas and comparisons among healthy areas and lesion areas showed different results.ConclusionONFH is a complex ischemic lesion caused by changes in local microcirculation. It mainly manifests as increased permeability of the vascular wall, blood stasis in the posterior circulation, high intraosseous pressure in the femoral head, and decreased arterial blood flow. The application of DCE-MRI scanning to quantitatively analyze the visual manifestations of microcirculation after early ONFH is an ideal method to study the microcirculation changes of necrotic femoral heads.

ABSTRACT Carbapenem-resistant Klebsiella pneumoniae (CRKP) has caused wide dissemination among pediatric patients globally and thus has aroused public concern. Here, we investigated the clinical epidemiological characteristics of 140 nonreplicate clinical K. pneumoniae strains isolated from pediatric patients between January and December 2021. Of all isolates, 16.43% (23 of 140) were CRKP strains, which predominantly contained KPC carbapenemase. wzi sequencing demonstrated that KL47 (65.22%, 15 of 23) was the most frequent capsular type, followed by KL64 (17.39%, 4 of 23). A total of 23 CRKP strains were classified into three different O-genotypes, including OL101 (65.22%, 15 of 23), O1 (26.09%, 6 of 23), and O3 (8.7%, 2 of 23). Interestingly, KL47 strains were strongly associated with OL101, while KL64 strains were all linked with O1. Some capsule-deficient strains were identified by serological typing, phage-typing, depolymerase-typing, and uronic acid assay. In this study, compared with healthy children, higher titers of anti-capsular polysaccharides (CPS) IgG were first detected in the sera of K47 and K64 K. pneumoniae-infected children, which had the effective bactericidal activity against corresponding serotype K. pneumoniae strains. These findings will facilitate the development of novel therapeutic and vaccine strategies against K. pneumoniae infection in children. IMPORTANCE The emergence of carbapenem-resistant Klebsiella pneumoniae (CRKP) strains resistant to numerous antibiotics and the limited therapeutic options available have become an urgent health threat to the immunocompromised pediatric population. Vaccines and antibodies, especially those targeting capsular polysaccharides, may be novel and effective prevention and treatment options. Thus, it is important to understand the spread of CRKP in pediatric populations. This research presents OL101:KL47 and O1:KL64 as the predominant combinations among CRKP strains in children in Shanghai, China. The primary carbapenemase gene is KPC in CRKP strains. Additionally, this study found elevated levels of anti-CPS IgG against K47 and K64 K. pneumoniae strains in pediatric patients for the first time. The significant bactericidal activity of these anti-CPS IgGs was confirmed.

ObjectivesAlthough hypervirulent Klebsiella pneumoniae (hvKp) is an increasing public health problem, there remains limited epidemiological information regarding hvKp infections in children. Here, we conducted a clinical, molecular and phenotypic surveillance of hvKp strains in a pediatric population.MethodsNon-repetitive K. pneumoniae (Kp) strains consecutively collected during 2019-2020 were screened for hypervirulence genes (prmpA, prmpA2, iucA, iroB, and peg344) using PCR. Positive strains were further characterized by four phenotypic assays (string test, serum killing assay, siderophore production, Galleria mellonella lethality assay), followed by murine sepsis model to determine virulence in vitro and in vivo. Also, capsular types, sequence types, plasmid replicon types, antimicrobial resistance determinants and susceptibility were analyzed.ResultsA total of 352 isolates were collected, wherein 83 (23.6%) were hypervirulence genes-positive Kp (hgKp). A significant increase in KPC-2-producing KL47-ST11 among hgKp strains was observed, from 5.3% (1/19) in 2019 to 67.6% (25/37) in 2020 (P

Polyploid plants, an important source for the selection of ornamental plants for their advantages of faster growth, higher yields, and stronger adaptability to an adverse environment, play an essential role in the development of economic plants for agricultural stress. The methodology has been improved to decrease blindness and increase the efficiency of ornamental plants’ polyploid breeding in the long term. The progress of research on ornamental plants related to natural polyploidy, chromosome doubling, the 2n gametes pathway, and plant ploidy identification are reviewed in this paper. The main routes in polyploid breeding are chromosome doubling and sexual hybridization. Screening of suitable induction methods and plant material should be enhanced in chromosome doubling to improve induction efficiency. Regarding polyploid breeding, the utilization and research on 2n gametes produced by natural conditions or artificial induction should be strengthened to shorten the breeding years. Therefore, further research should strengthen the combination of chromosome doubling and sexual hybridization to improve breeding efficiency and strengthen the research and application of polyploid plants. This thesis review provides some reference value for polyploid breeding in ornamental plants.

Nano-fertilizer has been dubbed ‘the fertilizer of the 21st century’, and it is already being used extensively in agriculture. Zinc oxide nanoparticles (ZnO-NPs) have excellent biological properties and are expected to be an ideal choice for plant zinc fertilizer. Tea is one of the top three beverages in the world, and improving the quality of tea is a priority in its research field. In this study, different concentrations (0, 10, 50, 100, 150, and 200 mg·L−1) of ZnO-NPs were sprayed on tea leaves to investigate their effects on volatile aroma substances and biochemical aspects of tea leaves. The results revealed that various concentrations of ZnO-NPs had different effects on physiological indexes. The concentration of 150 mg·L−1 of ZnO-NPs enhanced chlorophyll content, while the 100 mg·L−1 concentration of ZnO-NPs promoted the accumulation of soluble proteins and the activity of antioxidant enzymes, including a decrease in the content of malondialdehyde. In addition, the ZnO-NPs spray reduced the content of tea polyphenols. A total of 27 volatiles were identified under six treatments, with benzene being the common compound with an average content of 45.97%. Ethanolamine and cis-3-hexenyl acetate were the other two major compounds. It was concluded that the presence of ZnO-NPs improved the antioxidant system of teas, increased soluble protein content and provided better reactive oxygen species protection for plants, especially in the case of ZnO-NPs at 100 mg·L−1. We highlighted that ZnO-NPs application was a favorable way to improve tea trees growth.

As a promising oil species, Styrax tonkinensis has great potential as a biofuel due to an excellent fatty acid composition. However, frequent flooding caused by global warming and the low tolerance of the species to waterlogging largely halted its expansion in waterlogged areas. To explore endogenous hormones and phytohormone-related molecular response mechanism of S. tonkinensis under waterlogging, we determined 1-aminocyclopropane-1-carboxylic acid (ACC) and three phytohormone content (ABA, abscisic acid; SA, salicylic acid; IAA, indole-3-acetic acid) and analyzed the transcriptome of its seedlings under waterlogged condition of 3–5 cm. The sample collecting time was 0, 9, 24, and 72 h, respectively. It was concluded that ACC presented an upward trend, but other plant hormones showed a downward trend from 0 to 72 h under waterlogging stress. A total of 84,601 unigenes were assembled with a total length of 81,389,823 bp through transcriptome analysis. The GO enrichment analysis of total differentially expressed genes (DEGs) revealed that 4,637 DEGs, 8,238 DEGs, and 7,146 DEGs were assigned into three main GO functional categories in 9 vs. 0 h, 24 vs. 0 h, and 72 vs. 0 h, respectively. We also discovered several DEGs involved in phytohormone synthesis pathway and plant hormone signaling pathway. It was concluded that the decreased transcription of PYL resulted in the weak ABA signal transduction pathway. Moreover, decreased SA content caused by the low-expressed PAL might impact the resistance of S. tonkinensis seedlings under waterlogging stress. Our research may provide a scientific basis for the understanding of the endogenous hormone response mechanism of S. tonkinensis to waterlogging and lay a foundation for further exploration of the waterlogging defect resistance genes of S. tonkinensis and improving its resistance to waterlogging stress.

Styrax tonkinensis has great potential as a biofuel feedstock source having industrial oilseeds with excellent fatty acids (FAs) composition and good fuel properties. Photosynthesis in the developing pericarp could affect the carbon distribution in kernel. During kernel development, more carbon sources are allocated to starch rather than lipid, when the pericarp photosynthesis is reduced by fruit shading treatment. After shading the fruits at 50 days after flowering (DAF), samples of shaded fruit (FSK) and controls (CK) were collected at 80 DAF and analyzed using the proteomic method. We identified 3,181 proteins, of which 277 were differentially expressed proteins, all downregulated in the FSK group. There were 56 proteins found involved in carbohydrate metabolism and lipid biosynthesis leading to oil accumulation with their iTRAQ ratios of FSK/CK ranging from 0.7123 to 1.1075. According to the qRT-PCR analyses, the key genes related to FA and triacylglycerol (TAG) biosynthesis were significantly downregulated between 60 and 90 DAF especially at 80 DAF, while the key genes involved in starch biosynthesis and FA desaturase had no significant difference between the two groups at 80 DAF. Fruit shading is a negative treatment for lipid accumulation but not starch accumulation by restraining enzymic protein expression involved in FA and TAG biosynthesis during S. tonkinensis kernel development.

Cartilage regeneration is dependent on cellular-extracellular matrix (ECM) interactions. Natural ECM plays a role in mechanical and chemical cell signaling and promotes stem cell recruitment, differentiation and tissue regeneration in the absence of biological additives, including growth factors and peptides. To date, traditional tissue engineering methods by using natural and synthetic materials have not been able to replicate the physiological structure (biochemical composition and biomechanical properties) of natural cartilage. Techniques facilitating the repair and/or regeneration of articular cartilage pose a significant challenge for orthopedic surgeons. Whereas, little progress has been made in this field. In recent years, with advances in medicine, biochemistry and materials science, to meet the regenerative requirements of the heterogeneous and layered structure of native articular cartilage (AC) tissue, a series of tissue engineering scaffolds based on ECM materials have been developed. These scaffolds mimic the versatility of the native ECM in function, composition and dynamic properties and some of which are designed to improve cartilage regeneration. This review systematically investigates the following: the characteristics of cartilage ECM, repair mechanisms, decellularization method, source of ECM, and various ECM-based cartilage repair methods. In addition, the future development of ECM-based biomaterials is hypothesized.

Using nanoparticles (NPs) to effectively mitigate the negative effects of abiotic stressors on plant growth and development will help to achieve sustainable agriculture. Although there have been some prior reviews in this area, bibliometrics is still lacking. In this study, the most productive nations or regions, journals, publishers, and scholars in this field were identified using an objective bibliometric examination of the pertinent material published in the Web of Science core database. To dig deeper for information, the keywords co-occurrence, collaboration network of countries/regions and authors, and network map of highly cited papers citation are used to characterize present advances and forecast potential future trends. The results show a growing interest in using nanoparticles to alleviate abiotic stressors. There has been an exponential increase in the number of relevant papers and citations. Moreover, Asian countries are the most active in this subject, even if the USA generates papers with the best overall quality. The most common publishers and journals in this area are Elsevier and Environmental Science-Nano, while Wu HH is currently the most active author. Even though many researchers have formed close partnerships, there is not yet a large collaborative group of researchers in this field. Gaps in the current scientific literature are highlighted, such as the lack of use of omics, especially multi-omics, to provide a more in-depth and comprehensive explanation of the molecular mechanisms by which NPs enhance plant resistance to abiotic stresses. This bibliometric study will provide a valuable reference for studying the evolution of the field and identifying research frontiers.

Tea has become one of the most popular drinks worldwide because of its special taste and health benefits. ‘Yuhua’ tea is a famous specialty of Nanjing, China, a green tea produced from Camelia sinensis. It belongs to the green tea category and is one of the top ten most famous teas in China. The physical and chemical properties of soil are very important to the quality of tea. However, at present, there are few instances of research on the soil of the ‘Yuhua’ tea cultivation area. To provide the theoretical basis for improving the final quality of ‘Yuhua’ tea by soil management measures, the effects of the soil’s physical and chemical properties on the contents of important chemical components (free amino acids, tea polyphenols, and caffeine) of ‘Yuhua’ tea in three different cultivation areas in Nanjing were studied. The quality of ‘Yuhua’ tea is greatly influenced by the physical and chemical properties of the soil in which the tea plant grows. The free amino acid content and tea polyphenol content of tea leaves were significantly and negatively correlated with soil bulk density, pH, and water-soluble calcium content, while a significantly positive correlation was noticed between the two criteria and soil effective nitrogen, phosphorus, and potassium content. Additionally, the growth of the tea tree will be hampered and perhaps stressed if the soil’s helpful mineral concentration is too low. The tea tree may produce more caffeine as a result, which could lower the quality of the tea leaves. Therefore, implementing targeted soil management techniques is the key to promoting tea tree growth and improving tea quality. This study laid the foundation for the adoption of corresponding soil management measures to improve the quality of ‘Yuhua’ tea.

Objectives: To investigate why coxsackievirus A6 (CVA6) has replaced enterovirus A71 (EV71) and coxsackievirus A16 (CVA16), which used to be the most predominant etiological agents, for hand, foot and mouth disease (HFMD) in children in Beijing, China. Methods: Sixty-four CVA6-positive samples were identified from 2010 to 2016 and selected for whole genome sequence amplification and analysis. Results: It was demonstrated that the whole genome sequences of CVA6s in this study were 7432–7435 nucleotides in length, and the different lengths were only in the 5′UTR region. The phylogenetic tree analysis of the full-length VP1 region of CVA6s indicated that the prevalent CVA6s in Beijing changed from the previous D2 sub-genotype to the D3 sub-genotype in 2013. In this study, two recombinant forms (RFs)– RF-C and RF-D – of CVA6 mainly appeared in 2010 and 2011. Since 2013, three recombinant CVA6 variants – RF-A, J and L – have been prevalent in children with HFMD in Beijing. The recombination region of RF-J was located at the 2C region, while RF-L had a new recombination point in the 3D region. The recombination of prevalent CVA6s in Beijing from 2013 to 2016 occurred within non-capsid regions of the genome, especially the P2 and P3 regions. Conclusions: The sub-genotype change and recombination of CVA6s indicated from this study may explain why CVA6 has become the predominant pathogen causing HFMD since 2013.

Abstract Background Styrax tonkinensis (Pierre) Craib ex Hartwich has great potential as a woody biodiesel species having seed kernels with high oil content, excellent fatty acid composition and good fuel properties. However, no transcriptome information is available on the molecular regulatory mechanism of oil accumulation in developing S. tonkinensis kernels. Results The dynamic patterns of oil content and fatty acid composition at 11 time points from 50 to 150 days after flowering (DAF) were analyzed. The percent oil content showed an up-down-up pattern, with yield and degree of unsaturation peaking on or after 140 DAF. Four time points (50, 70, 100, and 130 DAF) were selected for Illumina transcriptome sequencing. Approximately 73 million high quality clean reads were generated, and then assembled into 168,207 unigenes with a mean length of 854 bp. There were 5916 genes that were differentially expressed between different time points. These differentially expressed genes were grouped into 9 clusters based on their expression patterns. Expression patterns of a subset of 12 unigenes were confirmed by qRT-PCR. Based on their functional annotation through the Basic Local Alignment Search Tool and publicly available protein databases, specific unigenes encoding key enzymes, transmembrane transporters, and transcription factors associated with oil accumulation were determined. Three main patterns of expression were evident. Most unigenes peaked at 70 DAF, coincident with a rapid increase in oil content during kernel development. Unigenes with high expression at 50 DAF were associated with plastid formation and earlier stages of oil synthesis, including pyruvate and acetyl-CoA formation. Unigenes associated with triacylglycerol biosynthesis and oil body development peaked at 100 or 130 DAF. Conclusions Transcriptome changes during oil accumulation show a distinct temporal trend with few abrupt transitions. Expression profiles suggest that acetyl-CoA formation for oil biosynthesis is both directly from pyruvate and indirectly via acetaldehyde, and indicate that the main carbon source for fatty acid biosynthesis is triosephosphate originating from phosphohexose outside the plastid. Different sn-glycerol-3-phosphate acyltransferases are implicated in diacylglycerol biosynthesis at early versus late stages of oil accumulation. Triacylglycerol biosynthesis may be accomplished by both diacylglycerol and by phospholipid:diacylglycerol acyltransferases.

Plant functional traits are rarely used in tree species classification, and the impact of vertical canopy positions on collecting samples for classification also remains unclear. We aim to explore the feasibility and effectiveness of leaf traits in classification, as well as to detect the effect of vertical position on classification accuracy. This work will deepen our understanding of the ecological mechanism of natural forest structure and succession from new perspectives. In this study, we collected foliar samples from three canopy layers (upper, middle and lower) and measured their spectra, as well as eight well-known leaf traits. We used a leaf hyperspectral reflectance (LHR) dataset, leaf functional traits (LFT) dataset and LFT + LHR dataset to classify six dominant tree species in a subtropical evergreen broad-leaved forest. Our results showed that the LFT + LHR dataset achieved the highest classification results (overall accuracy (OA) = 77.65% and Kappa = 0.73), followed by the LFT dataset (OA = 74.26% and Kappa = 0.69) and the LHR dataset (OA = 69.06% and Kappa = 0.63). Along the vertical canopy, the OA and Kappa increased from the lower to the upper layers, and the combination data of the three canopy layers achieved the highest accuracy. For the individual tree species, the shade-tolerant species (including Machilus chinensis, Cryptocarya chinensis and Cryptocarya concinna) produced higher accuracies than the light-demanding species (including Schima superba and Castanopsis chinensis). Our results provide an approach for enhancing tree species recognition from the plant physiology and biochemistry perspective and emphasize the importance of vertical direction in forest community research.

Cadmium (Cd) is a trace element causing severe toxicity symptoms in plants, besides posing hazardous fitness issue due to its buildup in the human body through food chain. Nanoparticles (NPs) are recently employed as a novel strategy to directly ameliorate the Cd stress and acted as nano-fertilizers. The intend of the current study was to explore the effects of zinc oxide nanoparticles (ZnO-NPs; 50 mg/L) on plant growth, photosynthetic activity, elemental status and antioxidant activity in Oryza sativa (rice) under Cd (0.8 mM) stress. To this end, the rice plants are treated by Cd stress at 15 days after sowing (DAS), and the treatment was given directly into the soil. Supply of ZnO-NPs as foliar spray was given for five consecutive days from 30 to 35 DAS, and sampling was done at 45 DAS. However, rice plants supplemented with ZnO-NPs under the Cd toxicity revealed significantly increased shoot length (SL; 34.0%), root fresh weight (RFW; 30.0%), shoot dry weight (SDW; 23.07%), and root dry weight (RDW; 12.24%). Moreover, the ZnO-NPs supplement has also positive effects on photosynthesis related parameters, SPAD value (40%), chloroplast structure, and qualitatively high fluorescence observed by confocal microscopy even under Cd stress. ZnO-NPs also substantially prevented the increases of hydrogen peroxide (H2O2) and malondialdehyde (MDA) triggered by Cd. Physiological and biochemical analysis showed that ZnO-NPs increased enzymatic activities of superoxide dismutase (SOD; 59%), catalase (CAT; 52%), and proline (17%) that metabolize reactive oxygen species (ROS); these increases coincided with the changes observed in the H2O2 and MDA accumulation after ZnO-NPs application. In conclusion, ZnO-NPs application to foliage has great efficiency to improve biomass, photosynthesis, protein, antioxidant enzymes activity, mineral nutrient contents and reducing Cd levels in rice. This can be attributed mainly from reduced oxidative damage resulted due to the ZnO-NPs application.

β-cyclocitral (βCC), a main apocarotenoid of β-carotene, increases plants’ resistance against stresses. It has recently appeared as a novel bioactive composite in a variety of organisms from plants to animals. In plants, βCC marked as stress signals that accrue under adverse ecological conditions. βCC regulates nuclear gene expression through several signaling pathways, leading to stress tolerance. In this review, an attempt has been made to summarize the recent findings of the potential role of βCC. We emphasize the βCC biosynthesis, signaling, and involvement in the regulation of abiotic stresses. From this review, it is clear that discussing compound has great potential against abiotic stress tolerance and be used as photosynthetic rate enhancer. In conclusion, this review establishes a significant reference base for future research.

Styrax tonkinensis, whose seeds are rich in unsaturated fatty acids (UFAs), is a high oil value tree species, and the seed oil has perfect biodiesel properties. Therefore, the elucidation of the effect of 24-epibrassinolide (EBL) on fatty acid (FA) concentration and the expression of FA biosynthesis-related genes is critical for deeply studying the seed oil in S. tonkinensis. In this study, we aimed to investigate the changing trend of FA concentration and composition and identify candidate genes involved in FA biosynthesis under EBL treatment using transcriptome sequencing and GC-MS. The results showed that 5 μmol/L of EBL (EBL5) boosted the accumulation of FA and had the hugest effect on FA concentration at 70 days after flowering (DAF). A total of 20 FAs were identified; among them, palmitic acid, oleic acid, linoleic acid, and linolenic acid were the main components. In total, 117,904 unigenes were detected, and the average length was 1120 bp. Among them, 1205 unigenes were assigned to ‘lipid translations and metabolism’ in COG categories, while 290 unigenes were assigned to ‘biosynthesis of unsaturated fatty acid’ in KEGG categories. Twelve important genes related to FA biosynthesis were identified, and their expression levels were confirmed by quantitative real-time PCR. KAR, KASIII, and accA, encoding FA biosynthesis-related enzymes, all expressed the highest at 70 DAF, which was coincident with a rapid rise in FA concentration during seed development. FAD2 and FATB conduced to UFA and saturated fatty acids (SFA) accumulation, respectively. EBL5 induced the expression of FA biosynthesis-related genes. The concentration of FA was increased after EBL5 application, and EBL5 also enhanced the enzyme activity by promoting the expression of genes related to FA biosynthesis. Our research could provide a reference for understanding the FA biosynthesis of S. tonkinensis seeds at physiological and molecular levels.

Liquidambar formosana Hance has a highly ornamental value as an important urban greening tree species with bright and beautiful leaf color. To gain insights into the physiological and molecular mechanisms of L. formosana leaf color change, the leaves of three different clones were sampled every ten days from October 13, 2019, five times in total, which are S1, S2, S3, S4 and S5. Transcriptome sequencing was performed at S1 and S4. The chlorophyll content of the three clones decreased significantly, while the anthocyanins content of the three clones increased significantly in the coloring stage. The anthocyanins content of clone 2 was far more than that of the other two clones throughout the period of leaf color change. The transcriptome analysis showed that six DEGs related to anthocyanins biosynthesis, including CHS (chalcone synthase), CHI (chalcone isomerase), F3′H (flavonoid 3′-hydroxylase), DFR (dihydroflavonol 4-reductase), ANS (anthocyanidin synthase) and FLS (flavonol synthase), were found in three clones. Clone 2 has another three DEGs related to anthocyanins biosynthesis, including PAL (Phenylalanine ammonia-lyase), F3′5′H (flavonoid 3′,5′-hydroxylase) and UFGT (flavonoid 3-O-glucosyltransferase). We lay a foundation for understanding the molecular regulation mechanism of the formation of leaf color by exploring valuable genes, which is helpful for L. formosana breeding.

Nanoparticles (NPs) have recently emerged as potential agents for plants to ameliorate abiotic stresses by acting as nano-fertilizers. In this regard, the influence of the zinc oxide nanoparticles (ZnO-NPs) on plant responses to copper (Cu) stress has been poorly understood. Hence, the present study was executed to explore the role of ZnO-NPs (foliar) and 24-epibrassinolide (EBL; root dipping) individually or in combined form in the resilience of tomato (Solanum lycopersicum) plant to Cu stress. Tomato seeds were sown to make the nursery; and at 20 days after sowing (DAS) the plantlets were submerged in 10−8 M of EBL solution for 2 h, and subsequently transplanted in the soil-filled earthen pots. Cu concentration (100 mg kg−1) was applied to the soil at 30 DAS, whereas at 35 DAS plants were sprinkled with double distilled water (DDW; control), 50 mg/L of Zinc (Zn) and 50 mg/L of ZnO-NPs; and plant performance were evaluated at 45 DAS. It was evident that Cu-stress reduced photosynthesis (17.3%), stomatal conductance (18.1%), plant height (19.7%), and nitrate reductase (NR) activity (19.2%), but increased malondialdehyde (MDA; 29.4%), superoxide radical (O2-; 22.3%) and hydrogen peroxide (H2O2; 26.2%) content in S. lycopersicum. Moreover, ZnO-NPs and/or EBL implemented via different modes improved photosynthetic activity, stomatal aperture, growth, cell viability and activity of antioxidant enzymes and proline that augmented resilience of tomato plants to Cu stress. These observations depicted that application of ZnO-NPs and EBL could be a useful approach to assist Cu confiscation and stress tolerance against Cu in tomato plants grown in Cu contaminated sites.

The combination of climate change and land use change may have profound effects on terrestrial biodiversity in more significant ways than either has separately. However, most studies focus largely on the climate change impacts, which hampers our ability to develop appropriate conservation strategies in a dramatically changing world. Here, we predict the distributions of 191 Chinese endemic Rhododendron species under future climate and land use change, combining two dispersal constraint scenarios by using a species distribution model. We then assess the vulnerability and extinction risk of these species and identify areas at risk of highest species loss. We find that 52% of the species are predicted to expand and shift their geographic ranges, typically to the northwest and north. The remaining 48% of species are predicted to contract in geographic ranges under the 'perfect-dispersal' scenario. And only 7% of Rhododendron are predicted to keep 'still', while the rest of species shrank with varying degree under the 'no-dispersal' scenario. Species lost particularly at lower elevations, and we also identify four regions at particularly high risk from the impacts of climate and land use change, namely the parallel ridge-and-valley areas of eastern Sichuan, southeastern Tibet, western and eastern Yunnan, southern Shaanxi, plus scattered areas in Guangdong, Hainan and Taiwan. We conclude that Chinese endemic Rhododendron species at lower elevations are highly vulnerable to climate and land use change, facing an elevated risk of extinction under varying scenarios. These species therefore call for more attention and protection. We highlight the critical role of endemic Rhododendron species as good indicators for measuring, evaluating and understanding the effectiveness of our biodiversity conservation efforts. Our work provides insight into the status, trends and threats regarding endemic Rhododendron species, identifying risks and prioritizing conservation in a rapidly changing world.

Melia azedarach Linn. is a deciduous tree of the Melia genus in the Meliaceae family that is native to China. To study the mechanism of drought resistance in Melia azedarach and evaluate the drought resistance capacity of each provenance, we selected eight provenances (Shandong Kenli, Jiangsu Pizhou, Hubei Shayang, Jiangsu Xuanwu, Jiangxi Xihu, Jiangsu Jurong, Guangdong Luogang, and Henan Shihe) as the research subjects and set four levels of drought stress treatment (CK: 75% of field capacity, mild drought: 60% of field capacity, moderate drought: 45% of field capacity, and severe drought: 30% of field capacity). The results showed that the growth in the seedling height and the ground diameter, the leaf relative water content, transpiration rate (Tr), net photosynthetic rate (Pn), stomatal conductance (Gs), and the content of chlorophyll (Chl) decreased with the increasing stress levels, while the root–shoot ratio, water saturation deficit, and the contents of malondialdehyde (MDA) increased. The SOD in most provenances initially increased and then decreased, reaching a peak during moderate drought. At the late stage of treatment, the magnitude of the changes in the photosynthetic indicators was more pronounced than in the physiological indicators. Principal component analysis showed that the contribution of all four principal components under the three drought stresses was above 85%, which represented the majority of the original data. Combined with the affiliation function method and weights, the comprehensive evaluation value (D value) of the drought resistance was calculated for the eight provenances. Then, we obtained the order of drought resistance of the test materials under the three drought stresses, respectively. The combined results revealed that the drought resistance of Henan Shihe and Jiangxi Xihu was stronger, while the drought resistance of Guangdong Luogang and Hubei Shayang was weaker. Based on the above findings, we can select provenances with strong and weak drought resistance for transcriptome sequencing to screen drought-resistant genes for an in-depth study at the molecular level.

As the germ of a highly productive oil tree species, Styrax tonkinensis seeds have great potential to produce biodiesel and they have marvelous fatty acid (FA) composition. In order to explore the molecular regulatory mechanism of FA biosynthesis in S. tonkinensis seeds after methyl jasmonate (MJ) application, transcriptomic and metabolomic techniques were adopted so as to dissect the genes that are related to FA biosynthesis and their expression levels, as well as to discover the major FA concentration and composition. The results revealed that 200 μmol/L of MJ (MJ200) increased the crude fat (CF) mass fraction and generated the greatest impact on CF accumulation at 70 days after flowering. Twenty FAs were identified, among which palmitic acid, oleic acid, linoleic acid and linolenic acid were the major FAs, and the presence of MJ200 affected their concentrations variously. MJ200 could enhance FA accumulation through elevating the activity of enzymes that are related to FA synthesis. The number of differentially expressed genes increased with the seeds’ development in general. Fatty acid biosynthesis, the biosynthesis of unsaturated fatty acid, fatty acid elongation and glycerolipid metabolism were the main lipid metabolism pathways that were found to be involved. The changes in the expression levels of EAR, KAR, accA, accB and SAD2 were consistent with the changes in the CF mass fraction, indicating that they are important genes in the FA biosynthesis of S. tonkinensis seeds and that MJ200 promoted their expression levels. In addition, bZIP (which was screened by weighted correlation network analysis) also created significant impacts on FA biosynthesis. Our research has provided a basis for further studies on FA biosynthesis that is regulated by MJ200 at the molecular level and has helped to clarify the functions of key genes in the FA metabolic pathway in S. tonkinensis seeds.

Background: The conventional fertilization regime ignores the allometric characteristics of Quercus nuttallii seedlings, challenging them to meet the nutritional needs at each growth stage. This study was conducted to determine the impact of exponential fertilization on the growth and nutrient status of Q. nuttallii container seedlings. Methods: Two fertilization regimes (average/exponential) were performed on Q. nuttallii container seedlings, and varied gradients (0, 300, 500, 700, and 900 mg/seedling) of N supply were set for the two regimes. Result: N application promoted the seedling height, root collar diameter, total biomass, and N/P/K accumulation of Q. nuttallii, and the exponential fertilization obtained better effects in general. An appropriate amount of exponentially N application was beneficial to the growth of root system, whereas excessive dosages inhibited it. Judging from seedlings growth status and nutrient accumulation, 900 mg/seedling under exponential fertilization was adequate for Q. nuttallii seedlings. However, 500 and 700 mg/seedling under exponential fertilization may have advantages in improving seedlings’ stress resistance. Conclusions: Exponential fertilization did not only meet the nutrient requirements and promote the growth of Q. nuttallii seedlings, but also facilitated the root growth to indirectly accelerate the assimilation of N/P/K, therefore improving the afforestation quality.

Little attention has been paid to the impact of vertical canopy position on the leaf spectral properties of tall trees, and few studies have explored the ability of leaf spectra to characterize the variation of leaf traits across different canopy positions. Using a tower crane, we collected leaf samples from three canopy layers (lower, middle, and upper) and measured eight leaf traits (equivalent water thickness, specific leaf area, leaf carbon content, leaf nitrogen content, leaf phosphorus content, leaf chlorophyll content, flavonoid, and nitrogen balance index) in a subtropical evergreen broadleaved forest. We evaluated the variability of leaf traits and leaf spectral properties, as well as the ability of leaf spectra to track the variation of leaf traits among three canopy layers for six species within the entire reflectance spectrum. The results showed that the eight leaf traits that were moderately or highly correlated with each other showed significant differences along the vertical canopy profile. The three canopy layers of leaf spectra showed contrasting patterns for light-demanding (Castanopsis chinensis, Castanopsis fissa, Schima superba, and Machilus chinensis) and shade-tolerant species (Cryptocarya chinensis and Cryptocarya concinna) along the vertical canopy profile. The spectra at the lower and upper canopy layers were more sensitive than the middle layer for tracking the variation of leaf chlorophyll and flavonoid content. Our results revealed that it is important to choose an appropriate canopy layer for the field sampling of tall trees, and we suggest that flavonoid is an important leaf trait that can be used for mapping and monitoring plant growth with hyperspectral remote sensing.

The objective of this research was to determine the effect of zinc oxide nanoparticles (ZnONPs) and/or salicylic acid (SA) under arsenic (As) stress on rice (Oryza sativa). ZnONPs are analyzed for various techniques viz., X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). All of these tests established that ZnONPs are pure with no internal defects, and can be potentially used in plant applications. Hence, we further investigated for better understanding of the underlying mechanisms and the extent of ZnONPs and SA induced oxidative stress damages. More restricted plant growth, gas exchange indices, significant reduction in the SPAD index and maximum quantum yield (Fv/Fm) and brutal decline in protein content were noticed in As-applied plants. In contrast, foliar fertigation of ZnONPs and/or SA to As-stressed rice plants lessens the oxidative stress, as exposed by subordinate levels of reactive oxygen species (ROS) synthesis. Improved enzymatic activities of catalase (CAT), peroxidase (POX), and superoxide dismutase (SOD), proline and total soluble protein contents under ZnONPs and SA treatment plays an excellent role in the regulation of various transcriptional pathways participated in oxidative stress tolerance. Higher content of nitrogen (N; 13%), phosphorus (P; 10%), potassium (K; 13%), zinc (Zn; 68%), manganese (Mn; 14%), and iron (Fe; 19) in ZnONPs and SA treated plants under As-stress, thus hampered growth and photosynthetic efficiency of rice plants. Our findings suggest that toxicity of As was conquering by the application of ZnONPs and SA in rice plants.

Cadmium (Cd) stress is increasing at a high pace and is polluting the agricultural land. As a result, it affects animals and the human population via entering into the food chain. The aim of this work is to evaluate the possibility of amelioration of Cd stress through chitosan nanoparticles (CTS-NPs). After 15 days of sowing (DAS), Solanum lycopersicum seedlings were transplanted into maintained pots (20 in number). Cadmium (0.8 mM) was providing in the soil as CdCl2·2.5H2O at the time of transplanting; however, CTS-NPs (100 µg/mL) were given through foliar spray at 25 DAS. Data procured from the present experiment suggests that Cd toxicity considerably reduces the plant morphology, chlorophyll fluorescence, in addition to photosynthetic efficiency, antioxidant enzyme activity and protein content. However, foliar application of CTS-NPs was effective in increasing the shoot dry weight (38%), net photosynthetic rate (45%) and SPAD index (40%), while a decrease in malondialdehyde (24%) and hydrogen peroxide (20%) was observed at the 30 DAS stage as compared to control plants. On behalf of the current results, it is demonstrated that foliar treatment of CTS-NPs might be an efficient approach to ameliorate the toxic effects of Cd.

Styrax japonicus is a small ornamental tree with medicinal values, although its flowering period is short. To date, information about the morphological and physiological characteristics of the petals during the flowering period is limited. In this study, we observed the structure of the petals at the full flowering stage with a scanning electron microscope and detected the contents of nutrients, minerals, and endogenous hormones and the activities of enzymes at different flowering stages. The results showed that the content of soluble sugar exhibited an ‘increase-decrease’ trend, whereas the contents of soluble protein, nitrogen (N), phosphorus (P), and abscisic acid (ABA) showed a ‘decrease-increase’ pattern. The content of starch descended continuously, but the contents of potassium (K), gibberellic acid (GA3), indoleacetic acid (IAA), and malondialdehyde (MDA) ascended continuously. The activities of peroxidase (POD) and superoxide dismutase (SOD) first rose and then declined during the flowering period. Higher contents of soluble sugar, N, K, and IAA promoted S. japonicus flowering; meanwhile, lower contents of starch, soluble protein, P, and GA3 in addition to the lower activity of SOD might be some of the causes of the short flowering period. This work will serve as the foundation for a scientific technique to utilize the flowers and extend the flowering period in S. japonicus.

Background: The faulty development of the root system is a major threat that affects the survival rate of container seedlings of Sapium sebiferum in the transplanting and reforestation processes. The current study was conducted to determine the impact of biochar on the root growth and development of S. sebiferum container seedlings. Methods: Varied concentrations (1%, 3%, and 5%) of straw and bamboo biochar were applied in six groups, whereas the control group (CK) was only treated with matrix. Results: The treatment with 3% straw biochar (C2) proved to be the most effective soil conditioner for cultivating S. sebiferum seedlings. Moreover, C2 increased seedling height (58.92%); ground diameter (33.86%, biomass of the over-ground part (12.73 g), the underground part (7.48 g), and the fibrous part (0.076 g) compared to the CK (control). Conclusions: Biochar not only improved the root morphology by developing primary lateral roots, but it also accelerated the assimilation of N from the matrix to indirectly facilitate stem growth through enhancing NR activity. The change in root growth strategy contributed to the growth in S. sebiferum seedlings, thereby improving the survival rate during transplanting and reforestation.

Background Styrax tonkinensis is a great potential biofuel as the species contains seeds with a particularly high oil content. Understanding the nutrient distribution in different parts of the fruit is imperative for the development and enhancement of S. tonkinensis as a biodiesel feedstock. Methods From 30 to 140 days after flowering (DAF), the development of S. tonkinensis fruit was tracked. The morphology change, nutrient content, and activity of associated enzymes in the continuum of the pericarp, seed coat, and kernel were analyzed. Results Between 30 and 70 DAF, the main locus of dry matter deposition shifted from the seed coat to the kernel. The water content within the pericarp remained high throughout development, but at the end (130 DAF later) decreased rapidly. The water content within both the seed coat and the kernel consistently declined over the course of the fruit development (30–110 DAF). Between 70 and 80 DAF, the deposition centers for sugar, starch, protein, potassium, and magnesium was transferred to the kernel from either the pericarp or the seed coat. The calcium deposition center was transferred first from pericarp to the seed coat and then to the kernel before it was returned to the pericarp. The sucrose to hexose ratio in the seed coat increased between 30 and 80 DAF, correlating with the accumulation of total soluble sugar, starch, and protein. In the pericarp, the sucrose to hexose ratio peaked at 40 and 100 DAF, correlating with the reserve deposition in the following 20–30 days. After 30 DAF, the chlorophyll concentration of both the pericarp and the seed coat dropped. The maternal unit (the pericarp and the seed coat) in fruit showed a significant positive linear relationship between chlorophyll b/a and the concentration of total soluble sugar. The potassium content had significant positive correlation with starch (ρ = 0.673, p = 0.0164), oil (ρ = 0.915, p = 0.000203), and protein content (ρ = 0.814, p = 0.00128), respectively. The concentration of magnesium had significant positive correlation with starch (ρ = 0.705, p = 0.0104), oil (ρ = 0.913, p = 0.000228), and protein content (ρ = 0.896, p = 0.0000786), respectively. Calcium content had a significant correlation with soluble sugar content (ρ = 0.585, p = 0.0457). Conclusions During the fruit development of S. tonkinensis, the maternal unit, that is, the pericarp and seed coat, may act a nutrient buffer storage area between the mother tree and the kernel. The stage of 70–80 DAF is an important time in the nutrient distribution in the continuum of the pericarp, seed coat, and kernel. Our results described the metabolic dynamics of the continuum of the pericarp, seed coat, and kernel and the contribution that a seed with high oil content offers to biofuel.

Background: Styrax tonkinensis is an economic tree species with high timber, medicine, oil, and ornamental value. Its seed, containing a particularly high oil content, are widely studied for their biodiesel properties by nutritional components and oil body ultrastructure. However, their comprehensive biochemical compositions have not been studied. Methods: During S. tonkinensis kernel development, we collected samples from four time points for metabolite profiling and classification through gas chromatography-mass spectrometry and liquid chromatography-mass spectrometry. Results: A total of 187 and 1556 metabolites were obtained, respectively. All of the metabolites were grouped into 19 and 21 classes by their chemical properties and into 8 clusters based on their change trends, respectively. Among all the metabolites, carboxylic acids and derivatives, flavonoids, fatty acyls, glycerophospholipids, organooxygen compounds, prenol lipids, and steroids and steroid derivatives were the main components. Alanine, glutamine, tryptophan, tyrosine and valine were the five most abundant amino acids. Palmitic acid, stearic acid, oleic acid and linoleic acid were the four major free fatty acids. Flavans, flavonoid glycosides and o-methylated flavonoids were the three major flavonoids. The differential metabolites distributions between different time points were identified. A pathway enrichment was performed, which was mainly focused on three groups, amino acids metabolism, carbon flow from sucrose to lipid and secondary metabolites biosynthesis. Conclusions: It’s the first time to analyze the metabolite fingerprinting for developing S. tonkinensis kernels and identify varied kinds of flavonoids. We performed metabolite profiling, classification and pathway enrichment to assess the comprehensive biochemical compositions. Our results described the change in major metabolites and main metabolic processes during S. tonkinensis kernel development and provided a variety of bases for seed applications as biofuel or medicine.

Adventitious root (AR) formation from cuttings is the primary manner for the commercial vegetative propagation of trees. Cuttings is also the main method for the vegetative reproduction of Taxodium ‘Zhongshanshan’, while knowledge of the molecular mechanisms regulating the processes is limited. Here, we used mRNA sequencing and an isobaric tag for relative and absolute quantitation-based quantitative proteomic (iTRAQ) analysis to measure changes in gene and protein expression levels during AR formation in Taxodium ‘Zhongshanshan’. Three comparison groups were established to represent the three developmental stages in the AR formation process. At the transcript level, 4743 genes showed an expression difference in the comparison groups as detected by RNA sequencing. At the protein level, 4005 proteins differed in their relative abundance levels, as indicated by the quantitative proteomic analysis. A comparison of the transcriptome and proteome data revealed regulatory aspects of metabolism during AR formation and development. In summary, hormonal signal transduction is different at different developmental stages during AR formation. Other factors related to carbohydrate and energy metabolism and protein degradation and some transcription factor activity levels, were also correlated with AR formation. Studying the identified genes and proteins will provide further insights into the molecular mechanisms controlling AR formation.