High-performance GeSi/Ge multi-quantum well photodetector on a Ge-buffered Si substrate.

This work demonstrates a high-performance photodetector with a 4-cycle Ge0.86Si0.14/Ge multi-quantum well (MQW) structure grown by reduced pressure chemical vapor deposition techniques on a Ge-buffered Si (100) substrate. At -1 V bias, the dark current density of the fabricated PIN mesa devices is as low as 3 mA/cm2, and the optical responsivities are 0.51 and 0.17 A/W at 1310 and 1550 nm, respectively, corresponding to the cutoff wavelength of 1620 nm. At the same time, the device has good high-power performance and continuous repeatable light response. On the other hand, the temperature coefficient of resistance (TCR) of the device is as high as -5.18%/K, surpassing all commercial thermal detectors. These results indicate that the CMOS-compatible and low-cost Ge0.86Si0.14/Ge multilayer structure is promising for short-wave infrared and uncooled infrared imaging.

Genome-wide characterization and expression profiling of the HD-ZIP gene family in Acoraceae under salinity and cold stress.

The Homeodomain-Leucine Zipper (HD-ZIP) transcription factors play a pivotal role in governing various aspects of plant growth, development, and responses to abiotic stress. Despite the well-established importance of HD-ZIPs in many plants, their functions in Acoraceae, the basal lineage of monocots, remain largely unexplored. Using recently published whole-genome data, we identified 137 putative HD-ZIPs in two Acoraceae species, Acorus gramineus and Acorus calamus. These HD-ZIP genes were further classified into four subfamilies (I, II, III, IV) based on phylogenetic and conserved motif analyses, showcasing notable variations in exon-intron patterns among different subfamilies. Two microRNAs, miR165/166, were found to specifically target HD-ZIP III genes with highly conserved binding sites. Most cis-acting elements identified in the promoter regions of Acoraceae HD-ZIPs are involved in modulating light and phytohormone responsiveness. Furthermore, our study revealed an independent duplication event in Ac. calamus and a one-to-multiple correspondence between HD-ZIP genes of Ac. calamus and Ac. gramineus. Expression profiles obtained from qRT-PCR demonstrated that HD-ZIP I genes are strongly induced by salinity stress, while HD-ZIP II members have contrasting stress responses in two species. HD-ZIP III and IV genes show greater sensitivity in stress-bearing roots. Taken together, these findings contribute valuable insights into the roles of HD-ZIP genes in stress adaptation and plant resilience in basal monocots, illuminating their multifaceted roles in plant growth, development, and response to abiotic stress.

Impact of flaxseed gum on the aggregate structure, pasting properties, and rheological behavior of waxy rice starch.

This study examines the effects of flaxseed gum (FG) on the aggregate structure, pasting and rheological properties of waxy rice starch (WRS). Results display an increase in the ordered molecular structure (R1047/1024), relative crystallinity (RC), compactness (α), and microphase heterogeneity (ε, density degree of nanoaggregates, from 3.52 to 4.23) for WRS-FG complexes. These suggested FG facilitated the development of more organized molecular and crystalline structures of WRS, accompanied by the formation of ordered nanoaggregates with higher density (i.e., nano-aggregation structure). Also, FG addition resulted in the formation of enhanced gel network structure characterized by thicker layer walls and more uniform pores. These structural transformations contributed to a rise in gelatinization temperature (To, from 56.90 °C to 62.10 °C) and enthalpy (ΔH), as well as alterations in paste viscosities (PV, from 1285.00 mPa·s to 1734.00 mPa·s), and the rigidity of network structure (e.g., decreased loss tangent). These results indicate that FG could effectively regulate the techno-functional properties of WRS by rationally controlling the starch intrinsic structures of starch. And this study may improve the pasting and gelling properties of starch, thus driving the development of high-quality starchy foods and prolonging their shelf life, especially for glutinous rice flour products.

Scheduled Follow-Up and Association with Emergency Department Use and Readmission after Trauma.

BACKGROUND: After traumatic injury, 13-14% of patients utilize the emergency department (ED) and 11% are readmitted within 30 days. Decreasing ED visits and readmission represents a target for quality improvement. This cohort study evaluates risk factors for ED visits and readmission after trauma, focusing on outpatient follow-up. STUDY DESIGN: We conducted a retrospective chart review of adult trauma admissions from 1/1/2018-12/31/2021. Our primary exposure was outpatient follow-up, our primary outcome was ED use, and our secondary outcome was readmission. Multivariable logistic regression evaluated the association between primary exposure and outcomes, adjusting for factors identified on unadjusted analysis. RESULTS: 2,266 patients met inclusion criteria, with an 11.3% ED visit rate and 4.1% readmission rate. Attending follow-up did not have a significant association with ED visits (OR 0.99, 95% CI 0.99-2.01, p=0.05) or readmission rates (OR 1.68, 95% CI 0.95-2.99, p=0.08). Significant associations with ED use included non-white race, depression, anxiety, substance use disorder, discharge disposition, and being discharged with lines or drains. Significant associations with readmission included depression, anxiety, and discharge disposition. CONCLUSION: Emphasizing outpatient follow-up in trauma patients is not an effective target to decrease ED use or readmission. Future studies should focus on supporting patients with mental health comorbidities and investigating interventions to optimally engage with trauma patients after hospital discharge.

Insights into the hierarchical structure and physicochemical properties of starch isolated from fermented dough.

Understanding the hierarchical structure and physicochemical properties of starch isolated from fermented dough with different times (0-120 min) is valuable for improving the quality of fermented dough-based products. The results indicate that fermentation disrupted the starch granule surface and decreased the average particle size from 19.72 µm to 18.45 µm. Short-term fermentation (< 60 min) disrupted the crystalline, lamellar, short-range ordered molecular and helical structures of starch, while long-term fermentation (60-120 min) elevated the ordered degree of these structures. For example, relative crystallinity and double helix contents increased from 23.7 % to 26.8 % and 34.4 % to 37.2 %, respectively. During short-term fermentation, the structural amorphization facilitated interactions between starch molecular chains and water molecules, which increased the peak viscosity from 275.4 to 320.6 mPa·s and the swelling power from 7.99 to 8.52 g/g. In contrast, starches extracted from long-term fermented dough displayed the opposite results. Interestingly, the hardness and springiness of starch gels gradually decreased as fermentation time increased. These findings extend our understanding of the starch structure-property relationship during varied fermentation stages, potentially benefiting the production of better-fermented foods.

Risk factors for loss to follow-up after traumatic injury: An updated view of a chronic problem.

BACKGROUND: Loss to follow-up after traumatic injury occurs at rates of up to 47%. However, the most recent data are over a decade old, and recent changes in traumatic injury patterns necessitate an updated assessment of risk factors for loss to follow-up after trauma. METHODS: We conducted a retrospective chart review of trauma admissions from January 1, 2018 to December 31, 2021. Categorical variables were compared using χ2 analyses, and continuous variables were analyzed using Mann-Whitney Wilcoxon tests. Multivariable logistic regression was used to adjust for relevant factors identified on unadjusted analysis. RESULTS: Among 3,034 patients, overall loss to follow-up was 36.9%. Non-White patients, patients who underwent operations or non-surgical procedures, and patients discharged to rehabilitation facilities were more likely to have follow-up appointments within 30 days. Patients with substance use disorder and, among White patients, those with public insurance had higher loss to follow-up rates. Having a follow-up appointment scheduled with a primary care provider was the single most significant factor associated with attending a follow-up appointment. CONCLUSION: Social determinants of health, such as insurance status and substance use disorder, are associated with loss of follow-up after trauma. Primary care appointments are associated with the highest attendance rates, supporting that all patients should be offered primary care appointments after traumatic injury.

Genome-Wide Identification and Drought Stress Response Pattern of the NF-Y Gene Family in Cymbidium sinense.

Cymbidium sinense, a type of orchid plant, is more drought-resistant and ornamental than other terrestrial orchids. Research has shown that many members of the NUCLEAR FACTOR Y (NF-Y) transcription factor family are responsive to plant growth, development, and abiotic stress. However, the mechanism of the NF-Y gene family's response to abiotic stress in orchids has not yet been reported. In this study, phylogenetic analysis allowed for 27 CsNF-Y genes to be identified (5 CsNF-YAs, 9 CsNF-YBs, and 13 CsNF-YC subunits), and the CsNF-Ys were homologous to those in Arabidopsis and Oryza. Protein structure analysis revealed that different subfamilies contained different motifs, but all of them contained Motif 2. Secondary and tertiary protein structure analysis indicated that the CsNF-YB and CsNF-YC subfamilies had a high content of alpha helix structures. Cis-element analysis showed that elements related to drought stress were mainly concentrated in the CsNF-YB and CsNF-YC subfamilies, with CsNF-YB3 and CsNF-YC12 having the highest content. The results of a transcriptome analysis showed that there was a trend of downregulation of almost all CsNF-Ys in leaves under drought stress, while in roots, most members of the CsNF-YB subfamily showed a trend of upregulation. Additionally, seven genes were selected for real-time reverse transcription quantitative PCR (qRT-PCR) experiments. The results were generally consistent with those of the transcriptome analysis. The regulatory roles of CsNF-YB 1, 2, and 4 were particularly evident in the roots. The findings of our study may make a great contribution to the understanding of the role of CsNF-Ys in stress-related metabolic processes.

The Survival Benefit of Pegylated Liposomal Doxorubicin-Based Neoadjuvant Chemotherapy in the Management of Breast Cancer.

Purpose: This study aims to evaluate the short-term outcomes and prognosis and the cardiac safety of pegylated liposomal doxorubicin (PLD)-based neoadjuvant chemotherapy (NAC) compared with epirubicin-based therapy in breast cancer treatment. Methods: In total, 304 patients diagnosed with stages II and III breast cancer were enrolled that included 97 cases treated with PLD and 207 controls treated with epirubicin in NAC. The effectiveness of the antibreast cancer treatment was evaluated using overall survival (OS) and disease-free survival (DFS) metrics, whereas cardiac toxicity was measured through the left ventricular ejection fraction (LVEF) and electrocardiogram (ECG) assessments. Results: The 5-year DFS and OS rates in the PLD group were 84.5% and 88.7% (with 15 recurrences and 11 deaths), respectively, whereas in the control group, these rates were 72.9% and 79.2% (with 56 recurrences and 43 deaths). Regarding cardiac toxicity, there was no significant difference in ECG abnormalities or LVEF decline between the two groups. Conclusions: The study suggests that PLD-based NAC may provide substantial benefits in terms of DFS and OS, along with a safe cardiac toxicity profile, in patients with stage II-III breast cancer.

Bullet holes: A novel model to identify the most impactful gaps in the firearm homicide prevention laws of each state.

BACKGROUND: Firearm homicides (FH) are a major cause of mortality in the United States (US). Firearm law implementation is variable across states, and legislative gaps may represent opportunities for FH prevention. For each state, we sought to identify which firearm law category would have been most effective if implemented and how effective it would have been. METHODS: We conducted a retrospective cohort study examining the effects of firearm laws on FH rates in the 48 contiguous US states 2010-2019. Data were obtained from the CDC WONDER and FBI UCR databases, State Firearm Law Database, and US Census. Firearm laws were grouped into 14 categories. We assessed the association between the presence of each law category and FH rate as an incidence rate ratio (IRR) using a Poisson regression accounting for state population characteristics and laws of surrounding states. We estimated the IRR for each state that did not have a given law category present and determined which of these missing law categories would have been associated with the greatest reduction in FH rate. RESULTS: FH rates varied widely across states and increased from a mean of 3.2 (SD = 1.7) to 4.2 (SD = 2.9) FH per 100,000. All law categories were significantly associated with decreased FH rate (p < 0.05), with IRR ranging from 0.25-0.85. The most effective missing law category differed between states but was most commonly child access prevention (34.09% of states), assault weapons and large-capacity magazines (15.91%), preemption (15.91%), and concealed carry permitting (13.64%). In total across 2010-2019, we estimated that 129,599 fewer FH would have occurred with enactment of the most effective missing law category in each state. CONCLUSIONS: Modeling firearm law prevention of FH with regard to state legislative and population characteristics can identify the highest impact missing law categories in each state. These results can be used to inform efforts to reduce FH. LEVEL OF EVIDENCE: Level III, Prognostic/Epidemiological.

Breast Cancer Screening and BI-RADS Scoring Trends Before and During the COVID-19 Pandemic in an Academic Safety-Net Hospital.

BACKGROUND: Little is known about how the COVID-19 pandemic affected screening mammography rates and Breast Imaging Reporting and Data Systems (BI-RADS) categorizations within populations facing social and economic inequities. Our study seeks to compare trends in breast cancer screening and BI-RADS assessments in an academic safety-net patient population before and during the COVID-19 pandemic. PATIENTS AND METHODS: Our single-center retrospective study evaluated women ≥ 18 years old with no known breast cancer diagnosis who received breast cancer screening from March 2019-September 2020. The screening BI-RADS score, completion of recommended diagnostic imaging, and diagnostic BI-RADS scores were compared between the pre-COVID-19 era (from 1 March 2019 to 19 March 2020) and COVID-19 era (from 20 March 2020 to 30 September 2020). RESULTS: Among the 11,798 patients identified, screened patients were younger (median age 57 versus 59 years, p < 0.001) and more likely covered by private insurance (35.9% versus 32.3%, p < 0.001) during the COVID-19 era compared with the pre-COVID-19 era. During the pandemic, there was an increase in screening mammograms categorized as BI-RADS 0 compared with the pre-COVID-19 era (20% versus 14.5%, p < 0.0001). There was no statistically significant difference in rates of completion of diagnostic imaging (81.6% versus 85.4%, p = 0.764) or assignment of suspicious BI-RADS scores (BI-RADS 4-5; 79.9% versus 80.8%, p = 0.762) between the two eras. CONCLUSIONS: Although more patients were recommended to undergo diagnostic imaging during the pandemic, there were no significant differences in race, completion of diagnostic imaging, or proportions of mammograms categorized as suspicious between the two time periods. These findings likely reflect efforts to maintain equitable care among diverse racial groups served by our safety-net hospital.

Retracted: Arsenic Trioxide Inhibits the Metastasis of Small Cell Lung Cancer by Blocking Calcineurin-Nuclear Factor of Activated T Cells (NFAT) Signaling.

This publication has been retracted by the Editor due to the identification of non-original figure images and manuscript content that raise concerns regarding the credibility and originality of the study. Reference: Jin-Cheng Zheng, Ke-Jie Chang, Yu-Xiang Jin, Xue-Wei Zhao, Bing Li, Meng-Hang Yang. Arsenic Trioxide Inhibits the Metastasis of Small Cell Lung Cancer by Blocking Calcineurin-Nuclear Factor of Activated T Cells (NFAT) Signaling. Med Sci Monit 2019; 25:2228-2237. DOI: 10.12659/MSM.913091.

Molecular insights into self-incompatibility systems: From evolution to breeding.

Plants have evolved diverse self-incompatibility (SI) systems for outcrossing. Since Darwin's time, considerable progress has been made toward elucidating this unrivaled reproductive innovation. Recent advances in interdisciplinary studies and applications of biotechnology have given rise to major breakthroughs in understanding the molecular pathways that lead to SI, particularly the strikingly different SI mechanisms that operate in Solanaceae, Papaveraceae, Brassicaceae, and Primulaceae. These best-understood SI systems, together with discoveries in other "nonmodel" SI taxa such as Poaceae, suggest a complex evolutionary trajectory of SI, with multiple independent origins and frequent and irreversible losses. Extensive exploration of self-/nonself-discrimination signaling cascades has revealed a comprehensive catalog of male and female identity genes and modifier factors that control SI. These findings also enable the characterization, validation, and manipulation of SI-related factors for crop improvement, helping to address the challenges associated with development of inbred lines. Here, we review current knowledge about the evolution of SI systems, summarize key achievements in the molecular basis of pollen‒pistil interactions, discuss potential prospects for breeding of SI crops, and raise several unresolved questions that require further investigation.

Genome-Wide Identification of PEBP Gene Family in Two Dendrobium Species and Expression Patterns in Dendrobium chrysotoxum.

The PEBP gene family plays a significant role in regulating flower development and formation. To understand its function in Dendrobium chrysotoxum and D. nobile flowering, we identified 22 PEBP genes (11 DchPEBPs and 11 DnoPEBPs) from both species. We conducted analyses on their conserved domains and motifs, phylogenetic relationships, chromosome distribution, collinear correlation, and cis elements. The classification results showed that the 22 PEBPs were mainly divided into three clades, as follows: FT, MFT, and TFL1. A sequence analysis showed that most PEBP proteins contained five conserved domains, while a gene structure analysis revealed that 77% of the total PEBP genes contained four exons and three introns. The promoter regions of the 22 PEBPs contained several cis elements related to hormone induction and light response. This suggests these PEBPs could play a role in regulating flower development by controlling photoperiod and hormone levels. Additionally, a collinearity analysis revealed three pairs of duplicate genes in the genomes of both D. chrysotoxum and D. nobile. Furthermore, RT-qPCR has found to influence the regulatory effect of DchPEBPs on the development of flower organs (sepals, petals, lip, ovary, and gynostemium) during the flowering process (bud, transparent stage, and initial bloom). The results obtained imply that DchPEBP8 and DchPEBP9 play a role in the initial bloom and that DchPEBP7 may inhibit flowering processes. Moreover, DchPEBP9 may potentially be involved in the development of reproductive functionality. PEBPs have regulatory functions that modulate flowering. FT initiates plant flowering by mediating photoperiod and temperature signals, while TFL1 inhibits flowering processes. These findings provide clues for future studies on flower development in Dendrobium.

Genome-Wide Identification and Expression Analysis of WNK Kinase Gene Family in Acorus.

WNK (With No Lysine) kinases are members of serine/threonine protein kinase family, which lack conserved a catalytic lysine (K) residue in protein kinase subdomain II and this residue is replaced by either asparagine, serine, or glycine residues. They are involved in various physiological regulations of flowering time, circadian rhythms, and abiotic stresses in plants. In this study, we identified the WNK gene family in two species of Acorus, and analyzed their phylogenetic relationship, physiochemical properties, subcellular localization, collinearity, and cis-elements. The results showed twenty-two WNKs in two Acorus (seven in Ac. gramineus and fifteen in Ac. calamus) have been identified and clustered into five main clades phylogenetically. Gene structure analysis showed all WNKs possessed essential STKc_WNK or PKc_like superfamily domains, and the gene structures and conserved motifs of the same clade were similar. All the WNKs harbored a large number of light response elements, plant hormone signaling elements, and stress resistance elements. Through a collinearity analysis, two and fourteen segmental duplicated gene pairs were identified in the Ac. gramineus and Ac. calamus, respectively. Moreover, we observed tissue-specificity of WNKs in Acorus using transcriptomic data, and their expressions in response to salt stress and cold stress were analyzed by qRT-PCR. The results showed WNKs are involved in the regulation of abiotic stresses. There were significant differences in the expression levels of most of the WNKs in the leaves and roots of Acorus under salt stress and cold stress, among which two members in Ac. gramineus (AgWNK3 and AgWNK4) and two members in Ac. calamus (AcWNK8 and AcWNK12) were most sensitive to stress. In summary, this paper will significantly contribute to the understanding of WNKs in monocots and thus provide a set up for functional genomics studies of WNK protein kinases.

Glycosylated queuosines in tRNAs optimize translational rate and post-embryonic growth.

Transfer RNA (tRNA) modifications are critical for protein synthesis. Queuosine (Q), a 7-deaza-guanosine derivative, is present in tRNA anticodons. In vertebrate tRNAs for Tyr and Asp, Q is further glycosylated with galactose and mannose to generate galQ and manQ, respectively. However, biogenesis and physiological relevance of Q-glycosylation remain poorly understood. Here, we biochemically identified two RNA glycosylases, QTGAL and QTMAN, and successfully reconstituted Q-glycosylation of tRNAs using nucleotide diphosphate sugars. Ribosome profiling of knockout cells revealed that Q-glycosylation slowed down elongation at cognate codons, UAC and GAC (GAU), respectively. We also found that galactosylation of Q suppresses stop codon readthrough. Moreover, protein aggregates increased in cells lacking Q-glycosylation, indicating that Q-glycosylation contributes to proteostasis. Cryo-EM of human ribosome-tRNA complex revealed the molecular basis of codon recognition regulated by Q-glycosylations. Furthermore, zebrafish qtgal and qtman knockout lines displayed shortened body length, implying that Q-glycosylation is required for post-embryonic growth in vertebrates.

Genome-based identification of the CYP75 gene family in Orchidaceae and its expression patterns in Cymbidium goeringii.

With a great diversity of species, Orchidaceae stands out as an essential component of plant biodiversity, making it a primary resource for studying angiosperms evolution and genomics. This study focuses on 13 published orchid genomes to identify and analyze the CYP75 gene family belonging to the cytochrome P450 superfamily, which is closely related to flavonoid biosynthetic enzymes and pigment regulation. We found 72 CYP75s in the 13 orchid genomes and further classified them into two classes: CYP75A and CYP75B subfamily, the former synthesizes blue anthocyanins, while the latter is involved in the production of red anthocyanins. Furthermore, the amount of CYP75Bs (53/72) greatly exceeds the amount of CYP75As (19/72) in orchids. Our findings suggest that CYP75B genes have a more important evolutionary role, as red plants are more common in nature than blue plants. We also discovered unique conserved motifs in each subfamily that serve as specific recognition features (motif 19 belong to CYP75A; motif 17 belong to CYP75B). Two diverse-colored varieties of C. goeringii were selected for qRT-PCR experiments. The expression of CgCYP75B1 was significantly higher in the purple-red variant compared to the yellow-green variant, while CgCYP75A1 showed no significant difference. Based on transcriptomic expression analysis, CYP75Bs are more highly expressed than CYP75As in floral organs, especially in colorful petals and lips. These results provide valuable information for future studies on CYP75s in orchids and other angiosperms.

Genome-Wide Identification of TCP Gene Family in Dendrobium and Their Expression Patterns in Dendrobium chrysotoxum.

The TCP gene family are plant-specific transcription factors that play important roles in plant growth and development. Dendrobium chrysotoxum, D. nobile, and D. huoshanense are orchids with a high ornamental value, but few studies have investigated the specific functions of TCPs in Dendrobium flower development. In this study, we used these three Dendrobium species to analyze TCPs, examining their physicochemical properties, phylogenetic relationships, gene structures, and expression profiles. A total of 50 TCPs were identified across three Dendrobium species; they were divided into two clades-Class-I (PCF subfamily) and Class-II (CIN and CYC/TB1 subfamilies)-based on their phylogenetic relationships. Our sequence logo analysis showed that almost all Dendrobium TCPs contain a conserved TCP domain, as well as the existence of fewer exons, and the cis-regulatory elements of the TCPs were mostly related to light response. In addition, our transcriptomic data and qRT-PCR results showed that DchTCP2 and DchTCP13 had a significant impact on lateral organs. Moreover, changes in the expression level of DchTCP4 suggested its important role in the phenotypic variation of floral organs. Therefore, this study provides a significant reference for the further exploration of TCP gene functions in the regulation of different floral organs in Dendrobium orchids.

Continuous Analgesia with Intercostal Catheterization after Thoracoscopy.

BACKGROUND: There are few studies on continuous intercostal nerve block after single operation hole thoracoscopic surgery, that is, two-port thoracoscopic surgery. OBJECTIVE: To evaluate the analgesic effect of continuous intercostal nerve block after thoracoscopic surgery. METHODS: A total of 80 patients who underwent single operation hole thoracoscopic surgery in our hospital between September 2020 and June 2021 were enrolled and divided into two groups. Based on basic analgesia, an intercostal catheter was placed during the operation for continuous intercostal block analgesia after the operation in the experimental group (group A, n = 40). The control group (group B, n = 40) was treated with sufentanil intravenous analgesia after surgery, which is namely "basic analgesia." The postoperative pain scores, restlessness during the recovery period, effect on reducing opioid use, postoperative chest complications, patient satisfaction, etc., were compared between the two groups. RESULTS: The pain scores of patients in group A were significantly lower compared with those in group B at 12, 24, 36, and 48 hours after surgery (3.325 ± 1.163 vs. 4.550 ± 1.176, 2.650 ± 1.001 vs. 4.000 ± 1.038, 2.325 ± 0.917 vs. 3.700 ± 0.966, and 1.775 ± 1.050 vs. 3.150 ± 1.075, p < 0.001, respectively). Sufentanil consumption in group A was significantly lower than in group B at 48 hours after surgery (98.625 ± 4.158 vs. 106.000 ± 7.228, p < 0.001). CONCLUSION: Multimodal analgesia is ideal for early pain control after thoracotomy. A continuous intercostal nerve block can effectively reduce postoperative pain in patients.

Research advances on the gene regulation of floral development and color in orchids.

Orchidaceae is one of the largest monocotyledon families and contributes significantly to worldwide biodiversity, with value in the fields of landscaping, medicine, and ecology. The diverse phenotypes and vibrant colors of orchid floral organs make them excellent research objects for investigating flower development and pigmentation. In recent years, a number of orchid genomes have been published, laying the molecular foundation for revealing flower development and color presentation. In this article, we review transcription factors, the structural genes responsible for the floral pigment synthesis pathways, the molecular mechanisms of flower morphogenesis, and the potential relationship between flower type and flower color. This study provides a theoretical reference for the research on molecular mechanisms related to flower morphogenesis and color presentation, genetic improvement, and new variety creation in orchids.

MDM2-mediated Inhibitory Effect of Arsenic Trioxide on Small Cell Lung Cancer Cell Line by Degrading Mutant p53.

INTRODUCTION: Small cell lung cancer (SCLC) is featured by a high TP53 mutant rate. Our previous research found that arsenic trioxide (As2O3) could significantly inhibit the growth and metastasis of SCLC. Studies have shown that the degradation of mutant p53 mediated by murine double minute 2 (MDM2) can be induced by As2O3, which probably contributes to the inhibition of SCLC, but the detailed mechanism is still unclear. We aimed to testify that As2O3 can inhibit the growth of SCLC cells by degrading mutant p53 protein via binding to MDM2. METHODS: CCK-8 assay, cell cycle analysis, and western blot of apoptosis markers were used to evaluate the inhibitory effect of As2O3 on NCI-H446 cells (containing mutant p53) and NCI-H1299 cells (p53 null). The effects of As2O3 on p53 and its downstream proteins were identified by western blot using mut-p53-knockdown and overexpressed cell models. MDM2-knockdown cell models were constructed, and western blot, co-IP of mut-p53, and ubiquitin were carried out to explore the mediating effect of MDM2 in As2O3 induced mut-p53 degradation. RESULTS: As2O3 inhibited proliferation and induced cell cycle arrest and apoptosis of SCLC cells in a dose- and timedependent manner. After mut-p53 knockdown or overexpressed, the inhibitory effect of As2O3 was dampened or enhanced. Additionally, As2O3-induced mut-p53 ubiquitination was significantly weakened after MDM2 knockdown. CONCLUSION: As2O3 could inhibit SCLC cells by inhibiting proliferation and inducing cell cycle arrest and apoptosis. These inhibitory effects were achieved at least in part by upregulating MDM2, which, in turn, promotes ubiquitination and degradation of mut-p53.