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1.
Ultrasonics ; 142: 107359, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38823151

RESUMO

Conventional surface acoustic wave (SAW) atomizers require a direct water supply on the surface, which can be complex and cumbersome. This paper presents a novel SAW atomizer that uses lateral acoustic wetting to achieve atomization without a direct water supply. The device works by simply pressing a piece of wetted paper strip against the bottom of an excited piezoelectric transducer. The liquid then flows along the side to the unmodified surface edge, where it is atomized into a well-converging mist in a stable and sustainable manner. We identified this phenomenon as the edge effect, using numerical simulation results of surface displacement mode. The feasibility of the prototype design was demonstrated by observing and investigating the integrated process of liquid extraction, transport, and atomization. We further explored the hydrodynamic principles of the change and breakup in liquid film geometry under different input powers. Experiments demonstrate that our atomizer is capable of generating high-quality fine liquid particles stably and rapidly even at very high input power. Compared to conventional SAW atomizer, the dispersion of mist width can be scaled down by 70%, while the atomization rate can be increased by 37.5%. Combined with the advantages of easy installation and robustness, the edge effect-based atomizer offers an attractive alternative to current counterparts for applications requiring high efficiency and miniaturization, such as simultaneous synthesis and encapsulation of nanoparticles, pulmonary drug delivery and portable inhalation therapy.

2.
Front Med (Lausanne) ; 11: 1410668, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38895182

RESUMO

The incidence of metabolic dysfunction-associated steatotic liver disease (MASLD) is continuously rising, evolving into a global health challenge. Concurrently, cases of hepatocellular carcinoma (HCC) associated with MASLD are also on the increase. Although traditional risk factors such as age, gender, and metabolic factors play significant roles in the development of HCC, it cannot be overlooked that MASLD, triggered by changes in modern lifestyle and dietary habits, may also exacerbate the risk of HCC, and this phenomenon is common even among non-obese individuals. Regrettably, MASLD often fails to receive timely diagnosis, resulting in a limited number of patients receiving HCC surveillance. Moreover, there is currently a lack of clear definition for the target population for surveillance beyond patients with cirrhosis. Consequently, MASLD-related HCC is often detected at a late stage, precluding the optimal timing for curative treatment. However, our understanding of the pathogenesis and progression of HCC remains limited. Therefore, this paper reviews relevant literature from recent years, delving into multiple dimensions such as pathogenesis, surveillance and diagnosis, prevention, and treatment, aiming to provide new ideas and directions for the prevention and treatment of MASLD-related HCC.

3.
Diagn Pathol ; 19(1): 87, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38909245

RESUMO

BACKGROUND: Pulmonary hamartomas are benign lung lesions. Histopathologically, pulmonary hamartoma is composed of varying amounts of mesenchymal elements, including chondroid tissue, mature adipose tissue, fibrous stroma, smooth muscle, and entrapped respiratory epithelium. Most pulmonary hamartoma cases are asymptomatic and found incidentally during imaging. They usually appear as well-circumscribed lesions with the largest dimension of less than 4 cm. Asymptomatic giant pulmonary hamartomas that more than 8 cm are rare. CASE PRESENTATION: In the current case report, a 12.0 × 9.5 × 7.5 cm lung mass was incidentally noticed in a 59-year-old female during a heart disease workup. Grossly, the lesion was lobulated with pearly white to tan-white solid cut surface and small cystic areas. Microscopically, representative tumor sections demonstrate a chondromyxoid appearance with relatively hypocellular stroma and entrapped respiratory epithelium at the periphery. No significant atypia is noted. No mitosis is noted, and the proliferative index is very low (< 1%) per Ki-67 immunohistochemistry. Mature adipose tissue is easily identifiable in many areas. Histomorphology is consistent with pulmonary hamartoma. A sarcoma-targeted gene fusion panel was further applied to this case. Combined evaluation of microscopic examination and sarcoma-targeted gene fusion panel results excluded malignant sarcomatous transformation in this case. The mediastinal and hilar lymph nodes are histologically benign. After surgery, the patient had an uneventful postoperative period. CONCLUSIONS: Giant pulmonary hamartoma is rare; our case is an example of a huge hamartoma in an asymptomatic patient. The size of this tumor is concerning. Thus, careful and comprehensive examination of the lesion is required for the correct diagnosis and to rule out co-existent malignancy.


Assuntos
Hamartoma , Humanos , Hamartoma/patologia , Hamartoma/cirurgia , Hamartoma/diagnóstico , Feminino , Pessoa de Meia-Idade , Pneumopatias/patologia , Pneumopatias/cirurgia , Pneumopatias/diagnóstico , Achados Incidentais , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/cirurgia , Neoplasias Pulmonares/diagnóstico
4.
Artigo em Inglês | MEDLINE | ID: mdl-38818861

RESUMO

The flow cytometry-based evaluation of TRBC1 expression has been demonstrated as a rapid and specific method for detecting T-cell clones in sCD3-positive TCRαß+ mature T-cell lymphoma. The aim of the study was to validate the utility of surface (s) TRBC1 and cytoplastic (cy) TRBC1 assessment in detecting clonality of sCD3-negative peripheral T-cell lymphomas (PTCLs), as well as exploring the existence and characteristics of sCD3-negative clonal T-cell populations with uncertain significance (T-CUS). Evaluation of sTRBC1 and cyTRBC1 were assessed on 61 samples from 37 patients with sCD3-negative PTCLs, including 26 angioimmunoblastic T-cell lymphoma (AITL) patients and 11 non-AITL patients. The sCD3-negative T-CUS were screened from 1602 patients without T-cell malignancy and 100 healthy individuals. Additionally, the clonality of cells was further detected through T-cell gene rearrangement analysis. We demonstrated the monotypic expression patterns of cyTRBC1 in all sCD3-negative PTCLs. Utilizing the cyTRBC1 evaluation assay, we identified a novel and rare subtype of sCD3-negative T-CUS for the first time among 13 out of 1602 (0.8%) patients without T-cell malignancy. The clonality of these cells was further confirmed through T-cell gene rearrangement analysis. This subset exhibited characteristics such as sCD3-cyCD3 + CD4 + CD45RO+, closely resembling AITL rather than non-AITL. Further analysis revealed that sCD3-negative T-CUS exhibited a smaller clone size in the lymph node and mass specimens compared to AITL patients. However, the clone size of sCD3-negative T-CUS was significantly lower than that of non-AITL patients in both specimen groups. In conclusion, we validated the diagnostic utility of cyTRBC1 in detecting sCD3-negative T-cell clonality, provided a comprehensive analysis of sCD3-negative T-CUS, and established a framework and provided valuable insights for distinguishing sCD3-negative T-CUS from sCD3-negative PTCLs based on their phenotypic properties and clone size.

6.
Micromachines (Basel) ; 15(1)2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38258254

RESUMO

Highly sensitive surface acoustic wave (SAW) sensors have recently been recognized as a promising tool for various industrial and medical applications. However, existing SAW sensors generally suffer from a complex design, large size, and poor robustness. In this paper, we develop a simple and stable delay line ultra-high frequency (UHF) SAW sensor for highly sensitive detection of temperature. A Z-shaped delay line is specially designed on the piezoelectric substrate to improve the sensitivity and reduce the substrate size. Herein, the optimum design parameters of extremely short-pitch interdigital transducers (IDTs) are given by numerical simulations. The extremely short pitch gives the SAW sensor ultra-high operating frequency and consequently ultra-high sensitivity. Several experiments are conducted to demonstrate that the sensitivity of the Z-shaped SAW delay line sensor can reach up to 116.685°/°C for temperature detection. The results show that the sensor is an attractive alternative to current SAW sensing platforms in many applications.

7.
Biosens Bioelectron ; 247: 115944, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38141441

RESUMO

Shear horizontal surface acoustic wave (SH-SAW) sensors are regarded as a promising alternative for label-free, sensitive, real time and low-cost detection. Nevertheless, achieving high sensitivity with SH-SAW has approached its limit imposed by the mass transport and probe-target affinity. We present here an SH-SAW biosensor accompanied by a unique Rayleigh wave-based actuator. The platform assembled on an ST-quartz substrate consists of dual-channel SH-SAW delay lines fabricated along a 90°-rotated direction, whilst another interdigital electrode (IDT) is orthogonally placed to generate Rayleigh waves so as to induce favourable streaming in the bio-chamber, enhancing the binding efficiency of the bio-target. Theoretical foundation and simulation have shown that Rayleigh acoustic streaming generates a level of agitation that accelerates the mass transport of the biomolecules to the surface. A fourfold improvement in sensitivity is achieved compared with conventional SH-SAW biosensors by means of complementary DNA hybridization with the aid of the Rayleigh wave device, giving a sensitivity level up to 6.15 Hz/(ng/mL) and a limit of detection of 0.617 ng/mL. This suggests that the proposed scheme could improve the sensitivity of SAW biosensors in real-time detection.


Assuntos
Técnicas Biossensoriais , Som , Acústica
8.
Chin Herb Med ; 15(4): 542-548, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38094008

RESUMO

Objective: Scutellarin is a primary active composition come from Erigeron breviscapus. It is well known that scutellarin has anti-inflammatory and antioxidant physiological functions. In this study, we detected the effects of scutellarin on hepatocyte cell apoptosis in type 2 diabetes mellitus (T2DM) rats. Methods: Sprague Dawley (SD) (6-8 weeks, 160-180 g) rats were randomly divided into six groups: control, model, scutellarin low-dose, medium-dose, high-dose treatment, and rosiglitazone positive groups; with 10 SD rats in each group (n = 10). The changes of biochemical factors in serum were detected by automatic biochemical instrument, the pathological changes of liver tissue were detected by hematoxylin and eosin (HE) staining, the apoptosis of liver tissue and cells was detected by tissue staining and flow analyzer, and the expression of apoptosis-related factors were determined by qPCR, Western blot and immunohistochemistry in liver tissues or cells. Results: The results showed that scutellarin decreased the levels of fasting blood glucose, total cholesterol, triglyceride, and low-density lipoprotein and increased the levels of high-density lipoprotein. Meanwhile, scutellarin decreased the levels of alanine transaminase (ALT) and aspartate transaminase (AST) and improved liver function. In addition, scutellarin suppressed the secretion of interleukin-1 (IL-1), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) and reduced hepatocyte apoptosis. Furthermore, scutellarin inhibited the expression of cleaved Caspase-3, Bax, and cytochrome C (Cyt-C) and promoted the expression of Bcl-2. Conclusion: Scutellarin can inhibit the apoptotic pathway, thereby relieving T2DM.

9.
PNAS Nexus ; 2(10): pgad299, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37822767

RESUMO

The underlying biological mechanisms that contribute to the heterogeneity of major depressive disorder (MDD) presentation remain poorly understood, highlighting the need for a conceptual framework that can explain this variability and bridge the gap between animal models and clinical endpoints. Here, we hypothesize that comparative analysis of molecular data from different experimental systems of chronic stress, and MDD has the potential to provide insight into these mechanisms and address this gap. Thus, we compared transcriptomic profiles of brain tissue from postmortem MDD subjects and from mice exposed to chronic variable stress (CVS) to identify orthologous genes. Ribosomal protein genes (RPGs) were down-regulated, and associated ribosomal protein (RP) pseudogenes were up-regulated in both conditions. A seeded gene co-expression analysis using altered RPGs common between the MDD and CVS groups revealed that down-regulated RPGs homeostatically regulated the synaptic changes in both groups through a RP-pseudogene-driven mechanism. In vitro analysis demonstrated that the RPG dysregulation was a glucocorticoid-driven endocrine response to stress. In silico analysis further demonstrated that the dysregulation was reversed during remission from MDD and selectively responded to ketamine but not to imipramine. This study provides the first evidence that ribosomal dysregulation during stress is a conserved phenotype in human MDD and chronic stress-exposed mouse. Our results establish a foundation for the hypothesis that stress-induced alterations in RPGs and, consequently, ribosomes contribute to the synaptic dysregulation underlying MDD and chronic stress-related mood disorders. We discuss the role of ribosomal heterogeneity in the variable presentations of depression and other mood disorders.

10.
Front Plant Sci ; 14: 1257541, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37771497

RESUMO

Castanea henryi is a monoecious woody food tree species whose yield and industrialization potential are limited by its low female-to-male flower ratio. Here, the male flowers on the male inflorescence of C. henryi were converted to female flowers by triple applications of exogenous cytokinin (CK) (N-(2-chloro-4-pyridyl)-N'-phenylurea, CPPU). To study the role of exogenous CK in flower sex determination, cytological and transcriptomic analyses were performed on samples from the five stages after CK treatment. Cytological analysis showed that stage 3 (nine days after the last CK treatment) was the critical stage in the differential development of the pistil primordium and stamen primordium. On this basis, one key module and two modules with significant positive correlations with stage 3 were identified by weighted gene co-expression network analysis (WGCNA), combined with transcriptome data. The CK and GA biosynthesis- and signaling-related genes, three transcription factor (TF) families, and 11 floral organ identity genes were identified in the related modules. In particular, the TFs WRKY47, ERF021, and MYB4, and floral organ identity genes AGL11/15, DEF, and SEP1 with large differences are considered to be critical regulators of sex determination in C. henryi. Based on these results, a genetic regulatory network for exogenous CK in the sex determination of flowers in C. henryi is proposed. This study contributes to the understanding of the role of CK in the sex regulation of flowers and provides new insights into the regulatory network of sex determination in C. henryi.

12.
Am J Surg Pathol ; 47(11): 1325-1331, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37515427

RESUMO

Indolent T-lymphoblastic proliferation (iT-LBP) consists of a proliferation of non-neoplastic TdT + T cells in extrathymic tissues, requiring no treatment. However, due to overlapping clinical and histologic features, distinguishing iT-LBP from T-cell acute lymphoblastic leukemia/lymphoblastic lymphoma (T-ALL/LBL) can be challenging. Recently, flow cytometry-based evaluation of TRBC1 has been used to detect of T-cell clonality in TCRαß + mature T-cell lymphomas and aid in the differential diagnosis between T-ALL and normal thymocytes. We present a case of iT-LBP with high-grade serous ovarian carcinoma (HGSOC). To investigate the potential utility of TRBC1 expression in distinguishing iT-LBP from T-ALL/LBL, we assessed both surface (s) and cytoplasmic (cy) TRBC1 expression patterns on blast cells from the patient with iT-LBP and HGSOC as well as 11 patients diagnosed with T-ALL/LBL. The results revealed that sTRBC1 and cyTRBC1 exhibited polytypic expression patterns in patient with iT-LBP and HGSOC, while cyTRBC1 showed monotypic expression in those with T-ALL/LBL. This suggests that evaluation of sTRBC1 and cyTRBC1 expression can serve as a simple, rapid, and effective approach to differentiate between iT-LBP and T-ALL/LBL.

13.
World J Gastrointest Oncol ; 15(6): 1073-1085, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37389110

RESUMO

BACKGROUND: Computed tomography (CT) imaging features are associated with risk stratification of gastric gastrointestinal stromal tumors (GISTs). AIM: To determine the multi-slice CT imaging features for predicting risk stratification in patients with primary gastric GISTs. METHODS: The clinicopathological and CT imaging data for 147 patients with histologically confirmed primary gastric GISTs were retrospectively analyzed. All patients had received dynamic contrast-enhanced CT (CECT) followed by surgical resection. According to the modified National Institutes of Health criteria, 147 lesions were classified into the low malignant potential group (very low and low risk; 101 lesions) and high malignant potential group (medium and high-risk; 46 lesions). The association between malignant potential and CT characteristic features (including tumor location, size, growth pattern, contour, ulceration, cystic degeneration or necrosis, calcification within the tumor, lymphadenopathy, enhancement patterns, unenhanced CT and CECT attenuation value, and enhancement degree) was analyzed using univariate analysis. Multivariate logistic regression analysis was performed to identify significant predictors of high malignant potential. The receiver operating curve (ROC) was used to evaluate the predictive value of tumor size and the multinomial logistic regression model for risk classification. RESULTS: There were 46 patients with high malignant potential and 101 with low-malignant potential gastric GISTs. Univariate analysis showed no significant differences in age, gender, tumor location, calcification, unenhanced CT and CECT attenuation values, and enhancement degree between the two groups (P > 0.05). However, a significant difference was observed in tumor size (3.14 ± 0.94 vs 6.63 ± 3.26 cm, P < 0.001) between the low-grade and high-grade groups. The univariate analysis further revealed that CT imaging features, including tumor contours, lesion growth patterns, ulceration, cystic degeneration or necrosis, lymphadenopathy, and contrast enhancement patterns, were associated with risk stratification (P < 0.05). According to binary logistic regression analysis, tumor size [P < 0.001; odds ratio (OR) = 26.448; 95% confidence interval (CI): 4.854-144.099)], contours (P = 0.028; OR = 7.750; 95%CI: 1.253-47.955), and mixed growth pattern (P = 0.046; OR = 4.740; 95%CI: 1.029-21.828) were independent predictors for risk stratification of gastric GISTs. ROC curve analysis for the multinomial logistic regression model and tumor size to differentiate high-malignant potential from low-malignant potential GISTs achieved a maximum area under the curve of 0.919 (95%CI: 0.863-0.975) and 0.940 (95%CI: 0.893-0.986), respectively. The tumor size cutoff value between the low and high malignant potential groups was 4.05 cm, and the sensitivity and specificity were 93.5% and 84.2%, respectively. CONCLUSION: CT features, including tumor size, growth patterns, and lesion contours, were predictors of malignant potential for primary gastric GISTs.

15.
Dalton Trans ; 52(18): 5999-6007, 2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37039563

RESUMO

OER (oxygen evolution reaction) is a critical reaction in several storage and conversion systems for renewable and clean electrochemical energies, including solar fuel devices, metal-air batteries, as well as regenerative fuel and water splitting cells. Regarding the shortcomings of OER, apart from the sluggish kinetics and high reaction overpotential, the reaction rate and overpotential are difficult to be optimized simultaneously. Herein, a novel hierarchical particle-sheet-structured Fe-doped NixP electrocatalyst is developed, which presents abundant interfaces between crystalline particle and amorphous sheet. The OER overpotential is reduced to 204 mV at 20 mA cm-2 current density, while it is reduced to 225 and 231 mV at 100 and 300 mA cm-2, respectively. The Fe-doped NixP electrocatalyst also shows fast reaction kinetics, whose Tafel slope is a remarkable 25 mV dec-1. For an electrolytic cell whose cathode and anode are Pt/C/NF and Fe-NixP/NF, respectively, a mere 1.446 V voltage is necessary to drive a 10 mA cm-2 current density for achieving overall water-splitting property. Notably, it also works stably at considerably high current densities of 500 and 1000 mA cm-2, representing high potential for commercial applications.

16.
Small ; 19(30): e2300431, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37029575

RESUMO

Silicon (Si) anode suffers from huge volume expansion which causes poor structural stability in terms of electrode material, solid electrolyte interface, and electrode, limiting its practical application in high-energy-density lithium-ion batteries. Rationally designing architectures to optimize the stress distribution of Si/carbon (Si/C) composites has been proven to be effective in enhancing their structural stability and cycling stability, but this remains a big challenge. Here, metal-organic frameworks (ZIF-67)-derived carbon nanotube-reinforced carbon framework is employed as an outer protective layer to encapsulate the inner carbon-coated Si nanoparticles (Si@C@CNTs), which features dual carbon stress-buffering to enhance the structural stability of Si/C composite and prolong their cycling lifetime. Finite element simulation proves the structural advantage of dual carbon stress-buffering through significantly relieving stress concentration when Si lithiation. The outer carbon framework also accelerates the charge transfer efficiency during charging/discharging by the improvement of lithium-ion diffusion and electron transport. As a result, the Si@C@CNTs electrode exhibits excellent long-term lifetime and good rate capability, showing a specific capacity of 680 mAh g-1 even at a high rate of 1 A g-1 after 1000 cycles. This work provides insight into the design of robust architectures for Si/C composites by stress optimization.

17.
Life (Basel) ; 13(2)2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36836771

RESUMO

Vertebrate ATP1B4 genes represent a rare instance of orthologous gene co-option, resulting in radically different functions of the encoded BetaM proteins. In lower vertebrates, BetaM is a Na, K-ATPase ß-subunit that is a component of ion pumps in the plasma membrane. In placental mammals, BetaM lost its ancestral role and, through structural alterations of the N-terminal domain, became a skeletal and cardiac muscle-specific protein of the inner nuclear membrane, highly expressed during late fetal and early postnatal development. We previously determined that BetaM directly interacts with the transcriptional co-regulator SKI-interacting protein (SKIP) and is implicated in the regulation of gene expression. This prompted us to investigate a potential role for BetaM in the regulation of muscle-specific gene expression in neonatal skeletal muscle and cultured C2C12 myoblasts. We found that BetaM can stimulate expression of the muscle regulatory factor (MRF), MyoD, independently of SKIP. BetaM binds to the distal regulatory region (DRR) of MyoD, promotes epigenetic changes associated with activation of transcription, and recruits the SWI/SNF chromatin remodeling subunit, BRG1. These results indicate that eutherian BetaM regulates muscle gene expression by promoting changes in chromatin structure. These evolutionarily acquired new functions of BetaM might be very essential and provide evolutionary advantages to placental mammals.

18.
BMC Plant Biol ; 23(1): 90, 2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36782110

RESUMO

BACKGROUND: In seed plants, the ovule is the precursor to the seed. The process of ovule development and differentiation is regulated by multiple factors, including starch metabolism and endogenous hormones. Castanea henryi produces nuts with high nutritional value. However, the high proportion of empty buds restricts the commercial use of the tree. Previous studies have shown that the empty bud phenotype is closely related to ovule abortion. If none of the ovules in the ovary expand rapidly and develop in 7-8 weeks after pollination, an empty bud will form. Therefore, we studied the development and molecular mechanisms underlying single seed formation in C. henryi. RESULTS: We found that 49 days after pollination (DAP) is a critical period for the formation of fertile and abortive ovules. The morphology and starch distribution of the fertile and abortive ovules differed significantly at 49 DAP. The fertile ovules were smooth and round in appearance, with a large amount of starch. In contrast, abortive ovules were smaller with only a small amount of starch. The embryo sac of the abortive ovule proceeded to develop abnormally, and the entire ovule lacked starch. We identified 37 candidate genes involved in metabolism with potential roles in the regulation of starch levels. Three ADP-glucose pyrophosphorylase (AGPase) genes, one granule-bound starch synthase (GBSS) gene, and two beta-amylase genes could affect starch accumulation. The levels of auxin, cytokinins, gibberellins, and jasmonic acid in fertile ovules were higher than those in abortive ovules. In addition, the levels of endogenous abscisic acid and salicylic acid in abortive ovules were higher than those in fertile ovules of the same age, consistent with the expression patterns of genes related to the synthesis of abscisic and salicylic acid and signal transduction. We identified and mapped the differentially expressed genes associated with hormone synthesis and signal transduction. CONCLUSIONS: These results improve our general understanding of the molecular mechanisms underlying single seed development in C. henryi and the phenomenon of empty buds, providing directions for future research.


Assuntos
Perfilação da Expressão Gênica , Transcriptoma , Sementes , Amido/metabolismo , Hormônios/metabolismo , Óvulo Vegetal , Regulação da Expressão Gênica de Plantas
20.
Front Plant Sci ; 13: 1032187, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36466242

RESUMO

Background and aims: In 1997, Tsou described the special differentiation of the connective tissues of some species of Theaceae to produce single-celled powders with unique patterns called pseudopollen. The purpose of this study was to investigate the morphological structure of the pseudopollen of Camellia oleifera (Theaceae) and to study the morphology of pseudopollen in seven other Camellia species. Methods: Scanning electron microscopy, paraffin section, light microscopy, transmission electron microscopy, histochemistry. Key result: C. oleifera pseudopollen was similar to normal pollen in macroscopic morphology but different microscopically. The normal pollen was starch-rich and yellow, with mostly reticulate exine ornamentation. In contrast, the pseudopollen was a white powder, single-celled and rich in protein, with parallel unbranched ridge lines on the outer wall, and originated from the parenchyma of the connective tissues. There are also differences in the micro-characteristics of normal and pseudopollen among different species in Camellia. Conclusion: There are great differences in morphological structure between C. oleifera and other species in Camellia normal pollen and pseudopollen; these results may indicate that the pseudopollen can be used as a taxonomic basis for Camellia, and the macroscopic similarity between pseudopollen and pollen and histochemical characteristics of pseudopollen can be a pollination strategy.

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