Advances in Single-Cell Transcriptome Sequencing and Spatial Transcriptome Sequencing in Plants.

"Omics" typically involves exploration of the structure and function of the entire composition of a biological system at a specific level using high-throughput analytical methods to probe and analyze large amounts of data, including genomics, transcriptomics, proteomics, and metabolomics, among other types. Genomics characterizes and quantifies all genes of an organism collectively, studying their interrelationships and their impacts on the organism. However, conventional transcriptomic sequencing techniques target population cells, and their results only reflect the average expression levels of genes in population cells, as they are unable to reveal the gene expression heterogeneity and spatial heterogeneity among individual cells, thus masking the expression specificity between different cells. Single-cell transcriptomic sequencing and spatial transcriptomic sequencing techniques analyze the transcriptome of individual cells in plant or animal tissues, enabling the understanding of each cell's metabolites and expressed genes. Consequently, statistical analysis of the corresponding tissues can be performed, with the purpose of achieving cell classification, evolutionary growth, and physiological and pathological analyses. This article provides an overview of the research progress in plant single-cell and spatial transcriptomics, as well as their applications and challenges in plants. Furthermore, prospects for the development of single-cell and spatial transcriptomics are proposed.

The development of nanocarriers for natural products.

Natural bioactive compounds from plants exhibit substantial pharmacological potency and therapeutic value. However, the development of most plant bioactive compounds is hindered by low solubility and instability. Conventional pharmaceutical forms, such as tablets and capsules, only partially overcome these limitations, restricting their efficacy. With the recent development of nanotechnology, nanocarriers can enhance the bioavailability, stability, and precise intracellular transport of plant bioactive compounds. Researchers are increasingly integrating nanocarrier-based drug delivery systems (NDDS) into the development of natural plant compounds with significant success. Moreover, natural products benefit from nanotechnological enhancement and contribute to the innovation and optimization of nanocarriers via self-assembly, grafting modifications, and biomimetic designs. This review aims to elucidate the collaborative and reciprocal advancement achieved by integrating nanocarriers with botanical products, such as bioactive compounds, polysaccharides, proteins, and extracellular vesicles. This review underscores the salient challenges in nanomedicine, encompassing long-term safety evaluations of nanomedicine formulations, precise targeting mechanisms, biodistribution complexities, and hurdles in clinical translation. Further, this study provides new perspectives to leverage nanotechnology in promoting the development and optimization of natural plant products for nanomedical applications and guiding the progression of NDDS toward enhanced efficiency, precision, and safety. This article is categorized under: Therapeutic Approaches and Drug Discovery > Emerging Technologies Nanotechnology Approaches to Biology > Nanoscale Systems in Biology.

Slow-Release Effect Assisted Crystallization for Sequential Deposition Realizes Efficient Inverted Perovskite Solar Cells.

The two-step sequential deposition strategy has been widely recognized in promoting the research and application of perovskite solar cells, but the rapid reaction of organic salts with lead iodide inevitably affects the growth of perovskite crystals, accompanied by the generation of more defects. In this study, the regulation of crystal growth was achieved in a two-step deposition method by mixing 1-naphthylmethylammonium bromide (NMABr) with organic salts. The results show that the addition of NMABr effectively delays the aggregation and crystallization behavior of organic salts; thereby, the growth of the optimal crystal (001) orientation of perovskite is promoted. Based on this phenomenon of delaying the crystallization process of perovskite, the "slow-release effect assisted crystallization" is defined. Moreover, the incorporation of the Br element expands the band gap of perovskite and mitigates material defects as nonradiative recombination centers. Consequently, the power conversion efficiency (PCE) of the enhanced perovskite solar cells (PSCs) reaches 20.20%. It is noteworthy that the hydrophobic nature of the naphthalene moiety in NMABr can enhance the humidity resistance of PSCs, and the perovskite phase does not decompose for more than 3000 h (30-40% RH), enabling it to retain 90% of its initial efficiency even after exposure to a nitrogen environment for 1200 h.

Anatomical Mechanisms of Leaf Blade Morphogenesis in Sasaella kogasensis 'Aureostriatus'.

There are limited studies on the cytology of bamboo leaf development from primordium to maturity. This study delves into the leaf morphological characteristics and growth patterns of Sasaella kogasensis 'Aureostriatus' and provides a three-dimensional anatomical analysis of cell division, expansion, and degradation. Leaves on the same branch develop bottom-up, while individual leaves develop the other way around. Like bamboo shoots and culms, the leaves follow a "slow-fast-slow" growth pattern, with longitudinal growth being predominant during their development. The growth zones of individual leaves included division, elongation, and maturation zones based on the distribution of growth space. By measuring 13,303 epidermal long cells and 3293 mesophyll cells in longitudinal sections of rapidly elongating leaves, we observed that in the rapid elongation phase (S4-S5), the division zone was located in the 1-2 cm segment at the bottom of the leaf blade and maintained a constant size, continuously providing new cells for leaf elongation, whereas in the late rapid elongation phase (S6), when the length of the leaf blade was approaching that of a mature leaf, its cells at the bottom of the blade no longer divided and were replaced by the ability to elongate. Furthermore, to gain an insight into the dynamic changes in the growth of the S. kogasensis 'Aureostriatus' leaves in the lateral and periclinal directions, the width and thickness of 1459 epidermal and 2719 mesophyll cells were counted in the mid-cross section of leaves at different developmental stages. The results showed that during the early stages of development (S1-S3), young leaves maintained vigorous division in the lateral direction, while periplasmic division gradually expanded from the bottom to the top of the leaf blade and the number of cell layers stabilized at S4. The meristematic tissues on both sides of the leaf were still able to divide at S4 but the frequency of the division gradually decreased, while cell division and expansion occurred simultaneously between the veins. At S6, the cells at the leaf margins and between the veins were completely differentiated and the width of the leaf blade no longer expanded. These findings revealed changes in cell growth anisotropically during the leaf development of S. kogasensis 'Aureostriatus' and demonstrated that leaf elongation was closely related to the longitudinal expansion of epidermal cells and proliferative growth of mesophyll cells, whereas the cell division of meristematic tissues and expansion of post-divisional cells contributed to the increases in blade width and thickness. The presented framework will facilitate a further exploration of the molecular regulatory mechanisms of leaf development in S. kogasensis 'Aureostriatus' and provide relevant information for developmental and taxonomic studies of bamboo plants.

Pharmacology of bioactive compounds from plant extracts for improving non-alcoholic fatty liver disease through endoplasmic reticulum stress modulation: A comprehensive review.

Background: Non-alcoholic fatty liver disease (NAFLD) is a prevalent chronic liver condition with significant clinical implications. Emerging research indicates endoplasmic reticulum (ER) stress as a critical pathogenic factor governing inflammatory responses, lipid metabolism and insulin signal transduction in patients with NAFLD. ER stress-associated activation of multiple signal transduction pathways, including the unfolded protein response, disrupts lipid homeostasis and substantially contributes to NAFLD development and progression. Targeting ER stress for liver function enhancement presents an innovative therapeutic strategy. Notably, the natural bioactive compounds of plant extracts have shown potential for treating NAFLD by reducing the level of ER stress marker proteins and mitigating inflammation, stress responses, and de novo lipogenesis. However, owing to limited comprehensive reviews, the effectiveness and pharmacology of these bioactive compounds remain uncertain. Objectives: To address the abovementioned challenges, the current review categorizes the bioactive compounds of plant extracts by chemical structures and properties into flavonoids, phenols, terpenoids, glycosides, lipids and quinones and examines their ameliorative potential for NAFLD under ER stress. Methods: This review systematically analyses the literature on the interactions of bioactive compounds from plant extracts with molecular targets under ER stress, providing a holistic view of NAFLD therapy. Results: Bioactive compounds from plant extracts may improve NAFLD by alleviating ER stress; reducing lipid synthesis, inflammation, oxidative stress and apoptosis and enhancing fatty acid metabolism. This provides a multifaceted approach for treating NAFLD. Conclusion: This review underscores the role of ER stress in NAFLD and the potential of plant bioactive compounds in treating this condition. The molecular mechanisms by which plant bioactive compounds interact with their ER stress targets provide a basis for further exploration in NAFLD management.

Overview of molecular mechanisms of plant leaf development: a systematic review.

Leaf growth initiates in the peripheral region of the meristem at the apex of the stem, eventually forming flat structures. Leaves are pivotal organs in plants, serving as the primary sites for photosynthesis, respiration, and transpiration. Their development is intricately governed by complex regulatory networks. Leaf development encompasses five processes: the leaf primordium initiation, the leaf polarity establishment, leaf size expansion, shaping of leaf, and leaf senescence. The leaf primordia starts from the side of the growth cone at the apex of the stem. Under the precise regulation of a series of genes, the leaf primordia establishes adaxial-abaxial axes, proximal-distal axes and medio-lateral axes polarity, guides the primordia cells to divide and differentiate in a specific direction, and finally develops into leaves of a certain shape and size. Leaf senescence is a kind of programmed cell death that occurs in plants, and as it is the last stage of leaf development. Each of these processes is meticulously coordinated through the intricate interplay among transcriptional regulatory factors, microRNAs, and plant hormones. This review is dedicated to examining the regulatory influences of major regulatory factors and plant hormones on these five developmental aspects of leaves.

Overwintering performance of bamboo leaves, and establishment of mathematical model for the distribution and introduction prediction of bamboos.

Bamboo has great economic values and is used extensively in many industries, and their natural distribution range was divided into 12 zones in China according to the temperature of their geographical distribution in previous works. Different bamboo species had significantly different abilities in low-temperature tolerance, which need to be considered carefully during ex-situ introduction. In this paper, we observed and evaluated the low-temperature damage of 19 bamboo species in winter, and measured the physiological changes of bamboo leaves. A total of 3060 leaf samples were obtained from 102 core collections in 34 bamboo species from the 5 regions of Chinese mainland for anatomical comparison, in order to screen out the key anatomical indicators related to their low-temperature tolerance and to establish a mathematical prediction model for bamboo introduction. The results showed that the low-temperature resistance of clustered bamboos was generally lower than that of the scattered bamboos. The decreased temperature led to the constant decrease of net photosynthetic rate and transpiration rate, but the increase of soluble sugar content in all bamboo species. There was no dormancy for all bamboo species in winter. The temperate bamboos showed lower photosynthesis as compared to tropical bamboos in winter. The leaf shape of bamboos was closely related to their distribution. A total of 13 leaf indicators were screened and more suitable to estimate the low-temperature tolerant abilities of bamboos and to predict their distribution. The MNLR (multiple nonlinear regression) mathematical model showed the highest fitting degree and the optimal prediction ability in the potential northernmost introduction range of bamboos. This study lay a foundation for bamboo introduction, and could also reduce the economic losses caused by the wrong introduction.

Research Progress on Stimulus-Responsive Polymer Nanocarriers for Cancer Treatment.

As drug carriers for cancer treatment, stimulus-responsive polymer nanomaterials are a major research focus. These nanocarriers respond to specific stimulus signals (e.g., pH, redox, hypoxia, enzymes, temperature, and light) to precisely control drug release, thereby improving drug uptake rates in cancer cells and reducing drug damage to normal cells. Therefore, we reviewed the research progress in the past 6 years and the mechanisms underpinning single and multiple stimulus-responsive polymer nanocarriers in tumour therapy. The advantages and disadvantages of various stimulus-responsive polymeric nanomaterials are summarised, and the future outlook is provided to provide a scientific and theoretical rationale for further research, development, and utilisation of stimulus-responsive nanocarriers.

IPAC integrates rewarding and environmental memory during the acquisition of morphine CPP.

The association between rewarding and drug-related memory is a leading factor for the formation of addiction, yet the neural circuits underlying the association remain unclear. Here, we showed that the interstitial nucleus of the posterior limb of the anterior commissure (IPAC) integrated rewarding and environmental memory information by two different receiving projections from ventral tegmental area (VTA) and nucleus accumbens shell region (NAcSh) to mediate the acquisition of morphine conditioned place preference (CPP). A projection from the VTA GABAergic neurons (VTAGABA) to the IPAC lateral region GABAergic neurons (IPACLGABA) mediated the effect of morphine rewarding, whereas the pathway from NAcSh dopamine receptor 1-expressing neurons (NAcShD1) to the IPAC medial region GABAergic neurons (IPACMGABA) was involved in the acquisition of environmental memory. These findings demonstrated that the distinct IPAC circuits VTAGABA→IPACLGABA and NAcShD1R→IPACMGABA were attributable to the rewarding and environmental memory during the acquisition of morphine CPP, respectively, and provided the circuit-based potential targets for preventing and treating opioid addiction.

O-GlcNAcylation of RAB10 promotes hepatocellular carcinoma progression.

Ras-related protein Rab-10 (RAB10) is involved in tumorigenesis and progression of hepatocellular carcinoma (HCC). Here, we found RAB10, O-GlcNAc transferase (OGT), and O-GlcNAcylation were upregulated in HCC. In addition, RAB10 protein level was prominently positively correlated with the expression of OGT. O-GlcNAcylation modification of RAB10 was then investigated. Here we showed that RAB10 interacts directly with OGT in HCC cell lines, Meanwhile, O-GlcNAcylation enhanced RAB10 protein stability. Furthermore, knockdown of OGT suppressed aggressive behaviors of HCC in vitro and in vivo, while elevated RAB10 reversed these. Taken together, these results indicated that OGT mediated O-GlcNAcylation stabilized RAB10, thus accelerating HCC progression.

Shoot differentiation from Dendrocalamus brandisii callus and the related physiological roles of sugar and hormones during shoot differentiation.

Only a few calli regeneration systems of bamboos were successfully established, which limited the research on the physiological mechanism of callus differentiation. In this study, we successfully established the callus differentiation systems of Dendrocalamus brandisii (Munro) via seeds. The results showed that the best medium for the callus induction of D. brandisii seeds was basal Murashige and Skoog (1962) (MS) media amended with 5.0 mg l-1 2,4-D and 0.5 mg l-1 kinetin (KT), and the optimal medium for shoot differentiation was the basal MS media supplemented with 4.0 mg l-1 6-benzylaminopurine (6-BA) and 0.5 mg l-1 1-Naphthaleneacetic acid (NAA). Callus tissues had apparent polarity in cell arrangement and developed their own meristematic cell layers. Alpha-amylase (α-amylase), starch phosphorylase (STP) and sucrose synthase (SUSY) played a dominant role in carbohydrate degradation in callus during shoot differentiation. The pentose phosphate pathway (PPP) and TCA pathways were up-regulated in the shoot-differentiated calli. The dynamics of 6-BA and KT contents in calli were consistent with their concentrations applied in medium. Indoleacetic acid (IAA) synthesis and the related signal transduction were down-regulated, whereas the endogenous CTK contents were up-regulated by the exogenous cytokinin (CTK) application in shoot-differentiated calli, and their related synthesis, transport and signal transduction pathways were also up-regulated. The down-regulated signal transduction pathways of IAA and abscisic acid (ABA) revealed that they did not play the key role in the shoot differentiation of bamboos. Gibberellins (GAs) also played a role in shoot differentiation based on the down-regulation of DELLA and the up-regulation of PIF4 genes. The overexpression of DbSNRK2 and DbFIF4 genes further confirmed the negative role of ABA and the positive role of GAs in shoot differentiation.

Quantitative evaluation of density variability in the lesion-lung boundary zone to differentiate pulmonary subsolid nodules.

Background: Transition of the CT values from nodule to peripheral normal lung is related to pathological changes and may be a potential indicator for differential diagnosis. This study investigated the significance of the standard deviation (SD) values in the lesion-lung boundary zone when differentiating between benign and neoplastic subsolid nodules (SSNs). Methods: From January 2012 to July 2021, a total of 229 neoplastic and 84 benign SSNs confirmed by pathological examination were retrospectively and nonconsecutively enrolled in this study. The diagnostic study was not registered with a clinical trial platform, and the study protocol was not published. Computed tomography (CT) values of the ground-glass component (CT1), adjacent normal lung tissue (CT2), and lesion-lung boundary zone (CT3) were measured consecutively. The SD of CT3 was recorded to assess density variability. The CT1, CT2, CT3, and SD values were compared between benign and neoplastic SSNs. Results: No significant differences in CT1 and CT2 were observed between benign and neoplastic SSNs (each P value >0.05). CT3 (-736.1±51.0 vs. -792.6±73.9; P<0.001) and its SD (135.6±29.6 vs. 83.6±20.6; P<0.001) in neoplastic SSNs were significantly higher than those in benign SSNs. Moreover, the SD increased with the invasiveness degree of neoplastic SSNs (r=0.657; P<0.001). The receiver operating characteristic (ROC) curve revealed that the area under the curve was 0.927 (95% CI: 0.896-0.959) when using the SD (cutoff value =106.98) as a factor to distinguish SSNs, which increased to 0.966 (95% CI: 0.934-0.985) when including nodules with a CT1 of ≥-715 Hounsfield units (HU) only (cutoff of SD 109.9, sensitivity 0.930, and specificity 0.914). Conclusions: The SD as an objective index is valuable for differentiating SSNs, especially for those with a CT1 of ≥-715 HU, which have a higher possibility of neoplasm if the SD is >109.9.

Impact of Meritocratic Beliefs of Newcomers on Creativity: A Career Construction Perspective.

Recent research suggests that meritocratic beliefs impact future-oriented activities. However, relatively little attention has been given to concomitant work outcomes, such as employee creativity. This study examines how the meritocratic beliefs of newcomers relate to employee creativity. We explore a serial mediation model where the meritocratic beliefs of newcomers heighten their meaning of work and learning adaptability, which increases employee creativity. We use questionnaires to survey 212 full-time employees from 10 manufacturing enterprises in China, who had joined their companies for less than a year. The results show that positive serial indirect effects of the meritocratic beliefs of newcomers on employee creativity via increased meaning of work and learning adaptability. Overall, the results provide new insight that may advance theoretical and practical implications on the pathways in which meritocratic beliefs may enhance employee creativity.

Clinical and Computed Tomography Characteristics of Solitary Pulmonary Nodules Caused by Fungi: A Comparative Study.

Purpose: To clarify the clinical and computed tomography (CT) indicators in distinguishing pulmonary nodules caused by fungal infection from lung cancers. Methods: From January 2013 to April 2022, 68 patients with solitary fungal nodules (64 were solid and 4 were mixed ground-glass nodules) and 140 cases with solid cancerous nodules with similar size were enrolled. Their clinical characteristics and CT manifestations of the solid nodules were summarized and compared, respectively. Results: Compared with patients with lung cancers, cases were younger (51.2 ± 11.5 vs 61.3 ± 10.2 years) and non-smokers (72.1% vs 57.9%) and immunocompromised (44.1% vs 17.9%) individuals were more common in patients with fungal nodules (each P < 0.05). The air crescent sign (ACS) (34.4% vs 0%), halo sign (HS) (23.4% vs 4.3%), and satellite lesions (45.3% vs 2.9%) were more frequently detected in fungal nodules than in cancerous ones (each P < 0.05). Air bronchogram similarly occurred in fungal and cancerous nodules, whereas the natural ones were more common in the former (100% vs 16.7%, P = 0.000). However, the fungal nodules had a lower enhancement degree (29.0 ± 19.2 HU vs 40.3 ± 28.3 HU, P = 0.038) and frequency of hilar and/or mediastinal lymph node enlargement (2.9% vs 14.3%, P = 0.013) compared with the cancerous nodules. Conclusion: In the younger, non-smoking and immunocompromised patients, a solitary pulmonary solid nodule with ACS, HS, satellite lesions and/or natural air bronchogram but without significant enhancement, fungal infection is a probable diagnosis.

Sensitivity and specificity of computed tomography hypodense sign when differentiating pulmonary inflammatory and malignant mass-like lesions.

Background: Hypodense sign (HyS) reportedly is associated with pulmonary fungal infection, while it also common in many non-fungal lesions. This study aims to determine the significance of a HyS presented on contrast-enhanced computed tomography (CECT) when distinguishing pulmonary inflammatory from malignant mass-like lesions. Methods: From January 2013 to January 2021, we retrospectively evaluated the clinical and computed tomography (CT) data of patients with pathologically confirmed pulmonary inflammatory lesions (ILs) and malignant lesions (MLs). We analyzed and compared the CT features of the HyS in MLs and ILs, and then evaluated whether the HyS helped to differentiate MLs and ILs. Results: There were significant differences in age and tumor markers between patients with ILs and MLs (both P<0.05). Compared with that in MLs, the occurrence of the HyS in ILs was higher (62.81% vs. 28.81%; P<0.0001). In ILs, more HyS were single, round or oval, well-defined, and had lower enhancement (ΔCT). Logistic regression analysis revealed that an ill-defined boundary, peripheral fibrosis, presence of a well-defined HyS, and a ΔCT value of the HyS <9.5 Hounsfield units (HU) were independent indicators for predicting ILs. After including the HyS CT features, the area under the curve (AUC) of the model predicting ILs increased from 0.953 to 0.986 with a sensitivity of 96.03% and a specificity of 94.03% (P=0.0027). Conclusions: The HyS is more common in ILs than in MLs. A single, regular, and well-defined HyS with a ΔCT value of <9.5 HU on CECT is highly suggestive of ILs. Combining the HyS with other morphological features could improve the diagnosis accuracy of pulmonary mass-like lesions.

Differential effects of trichostatin A on mouse embryogenesis and development.

Trichostatin A (TSA), a histone deacetylase (HDAC) inhibitor, can significantly improve the reprogramming efficiency of somatic cells. However, whether TSA has a detrimental effect on other kinds of embryos is largely unknown because of the lack of integrated analysis of the TSA effect on natural fertilized embryos. To investigate the effect of TSA on mouse embryo development, we analyzed preimplantation and post-implantation development of in vivo, in vitro fertilized, and parthenogenetic embryos treated with TSA at different concentrations and durations. In vivo fertilized embryos appeared to be the most sensitive to TSA treatment among the three groups, and the blastocyst formation rate decreased sharply as TSA concentration and treatment time increased. TSA treatment also reduced the livebirth rate for in vivo fertilized embryos from 56.59 to 38.33% but did not significantly affect postnatal biological functions such as the pups' reproductive performance and their ability for spatial learning and memory. Further analysis indicated that the acetylation level of H3K9 and H4K5 was enhanced by TSA treatment at low concentrations, while DNA methylation appeared to be also disturbed by TSA treatment only at high concentration. Thus, our data indicates that TSA has different effects on preimplantation embryonic development depending on the nature of the embryo's reproductive origin, the TSA concentration and treatment time, whereas the effect of TSA at the indicated concentration on postnatal function was minor.

Seed Germination and Seedling Growth of Dendrocalumus brandisii in vitro, and the Inhibitory Mechanism of Colchicine.

Bamboos seldom bloom and almost no seeds could be harvested, and, hence, few works are focused on germination physiology. Systematic research on the physiological effects of colchicine on germination and seedling growth of bamboo seeds is lacking. In this study, we finely recorded seed germination and seedling growth of Dendrocalamus brandisii in media supplemented with different colchicine concentrations. Physiological effects and mechanisms of colchicine were analyzed. The results showed that D. brandisii seeds were non-dormant, and seed lots achieved their highest germination rates on the 4th day and finished the whole germination period after 21 days. Colchicine inhibited seed germination and seedling growth but did not change its germination pattern. Seed germination and seedling growth decreased constantly with colchicine concentration. Colchicine showed more negative effects on seedling growth than on seed germination and root growth. High concentrations of colchicine retarded the development of plumules and even caused their aberrant development. Under tissue culture conditions, seed germination, and seedling growth relied mainly on the endogenous starch and soluble sugar degradation, in which α-amylase, STP, and SUSY played the key role. Colchicine inhibited seed germination and seedling growth by suppressing the α-amylase, STP, and SUSY activities. Colchicine showed more negative effects on sucrose degradation than on starch degradation during seed germination and seedling growth. This study provides new basic information on the seedling physiology for the genetic breeding of bamboo plants.

CT features and outcomes of newly developed pulmonary lesions in patients with Coronavirus Disease 2019 (COVID-19).

Background: In patients with coronavirus disease 2019 (COVID-19) pneumonia, whether new pulmonary lesions will continue to develop after treatment was unknown. This study aimed to determine whether new pulmonary lesions will develop after treatment in patients with COVID-19 pneumonia, and investigate their CT features and outcomes. Methods: This retrospective study included 56 consecutive patients with confirmed COVID-19 pneumonia from January 20 to March 5, 2020. Their initial and follow-up CT images and clinical data were reviewed. The CT manifestations of primary and newly developed pulmonary lesions and their changes after treatment were mainly evaluated. Results: Among the 56 patients (mean age: 48±15 years, 35 men) with COVID-19 pneumonia, 42 (75.0%) patients developed new pulmonary lesions during treatment. All new lesions developed before the nucleic acid test turned negative. Patients with new lesions were more likely to have lymphopenia (P=0.041) or increased C-reactive protein (CRP) levels (P<0.001) than those without new lesions. Of the 42 patients, 30 (71.4%) patients developed new lesions once, and 12 (28.6%) twice or thrice, which usually appeared when primary lesions were progressing (37, 88.1%) and 1-15 days after treatment. The newly developed lesions were usually multiple (38, 90.5%), distributed in the previously involved (39, 92.9%) or uninvolved (27, 64.3%) lobes, and manifested as ground-glass opacities (GGOs) with consolidation (23, 54.8%) or pure GGOs (19, 45.2%). After their occurrence, the new lesions in most patients (32, 76.2%) showed direct absorption, whereas those in some patients (10, 23.8%) progressed before absorption. Conclusion: During treatment, most patients with COVID-19 pneumonia will develop new pulmonary lesions, which usually manifest as multiple GGOs distributed around the primary lesions or in previously uninvolved lobes, and are subsequently absorbed directly.

Up-to-date comparison of robotic-assisted versus open distal pancreatectomy: A PRISMA-compliant meta-analysis.

BACKGROUND: Although robot-assisted distal pancreatectomy (RADP) has been successfully performed since 2003, its advantages over open distal pancreatectomy (ODP) are still uncertain. The objective of this meta-analysis is to compare the clinical and oncologic safety and efficacy of RADP vs ODP. METHODS: Multiple databases (PubMed, Medline, EMBASE, Web of Science, and Cochrane Library) were searched to identify studies that compare the outcomes of RADP and ODP (up to February, 2020). Fixed and random effects models were applied according to different conditions. RESULTS: A total of 7 studies from high-volume robotic surgery centers comprising 2264 patients were included finally. Compared with ODP, RADP was associated with lower estimated blood loss, lower blood transfusion rate, lower postoperative mortality rate, and shorter length of hospital stay. No significant difference was observed in operating time, the number of lymph nodes harvested, positive margin rate, spleen preservation rate, rate of severe morbidity, incidence of postoperative pancreatic fistula, and severe postoperative pancreatic fistula (grade B and C) between the 2 groups. CONCLUSIONS: With regard to perioperative outcomes, RADP is a safe and feasible alternative to ODP in centers with expertise in robotic surgery. However, the evidence is limited and more randomized controlled trials are needed to further clearly define this role.

Changes in spatial patterns of PM2.5 pollution in China 2000-2018: Impact of clean air policies.

To improve air quality, China has been implementing strict clean air policies since 2013. These policies not only substantially improved air quality but may also modify the spatial distribution of air pollution, since urban emission sources were under stricter control and some were moved to rural regions with lower air quality improvement targets and lacking of monitoring. Here, we predicted satellite-based monthly PM2.5 concentrations during 2000-2018 at a 1-km resolution with complete spatial-temporal coverage to analyze changes in the spatial pattern of PM2.5 pollution in China. We found that the PM2.5 concentration in urban regions was higher than that in rural regions of the same city by an average of 3.3 µg/m3 during 2000-2018. This urban-rural disparity in PM2.5 concentration significantly increased from 2.5 µg/m3 in 2000 and peaked in 2007 of 3.8 µg/m3, then it sharply declined by 49% during 2013-2018 with the implementation of clean air policies. This shrinkage in the urban-rural PM2.5 gap was partly due to the 1.3 µg/m3 greater average decrease in the PM2.5 level in the urban region than in the rural region of the same town during 2013-2018 on average. We also observed that cities that started monitoring earlier experienced greater decreases in the urban-rural PM2.5 difference, and regions surrounding monitor showed significantly greater PM2.5 decrease than regions far away from monitor during 2013-2018. Additionally, clean air policies modified the relationship between PM2.5 concentrations and per capita gross domestic product (GDP), leading to a lower PM2.5 level with the same per capita GDP after 2013. Emissions in rural and suburban regions should be considered to further improve air quality in China.