The factors affecting the behavior of non-specialized nectar-feeding passerines have received little attention in the literature on plant-pollinator interactions. Puya chilensis (Bromeliaceae) has sterile branch apice...The factors affecting the behavior of non-specialized nectar-feeding passerines have received little attention in the literature on plant-pollinator interactions. Puya chilensis (Bromeliaceae) has sterile branch apices that project outward from the inflorescence. In this study, we evaluate the functional role of sterile apices as support systems for bird foraging behavior. We recorded bird visitation and flower probing in the presence and absence of sterile branches during the spring seasons of 2021 and 2024. The results revealed that experimental plants with excised branches received fewer bird visits and flower probings than control plants, indicating that sterile branches play an important role in the nectar-feeding behavior of passerine birds in P. chilensis.展开更多
Epigenetics is the discipline of regulating cellular activity through chemical modification or modulation of noncoding RNAs without altering the nucleotide sequence.Studies on this topic include the exploration of DNA...Epigenetics is the discipline of regulating cellular activity through chemical modification or modulation of noncoding RNAs without altering the nucleotide sequence.Studies on this topic include the exploration of DNA methylation,histone modification,noncoding RNA regulation,and chromatin remodeling.Derived from the apical tissues of young permanent teeth,stem cells from apical papilla are odontogenic adult stem cells with high proliferation,self-renewal capacity,and differentiation potential.These cells play crucial roles in root formation and development.This article focuses on the two epigenetic regulatory mechanisms of histone modifications and non-coding RNA.This review summarizes,generalizes,and evaluates the status of research on the epigenetic regulation of the multidirectional differentiation of stem cells from the apical papilla,aiming to explore the mechanisms underlying the multidirectional differentiation process of these stem cells.展开更多
Comments Ebstein's Anomaly(EA)is a rare congenital heart disease(CHD)with an incidence of approximately 1 in 20,000.The pathognomonic feature involves apical displacement of the septal and posterior leaflets,resul...Comments Ebstein's Anomaly(EA)is a rare congenital heart disease(CHD)with an incidence of approximately 1 in 20,000.The pathognomonic feature involves apical displacement of the septal and posterior leaflets,resulting in valvular insufficiency and right ventricular(RV)remodeling.Untreated patients exhibit a cumulative mortality rate of up to 25% within the first decade,with heart failure(HF)and arrhythmias constituting the predominant causes of death.Current guidelines suggest that asymptomatic patients with accessory pathways may benefit from prophylactic ablation,though robust evidence specific to EA remains limited[1-3].展开更多
BACKGROUND Stem cells from apical papilla(SCAPs)represent promising candidates for bone regenerative therapies due to their osteogenic potential.However,enhancing their differentiation capacity remains a critical chal...BACKGROUND Stem cells from apical papilla(SCAPs)represent promising candidates for bone regenerative therapies due to their osteogenic potential.However,enhancing their differentiation capacity remains a critical challenge.Enhancer of zeste homolog 2(EZH2),a histone H3 lysine 27 methyltransferase,regulates osteogenesis through epigenetic mechanisms,but its role in SCAPs remains unclear.We hypothesized that EZH2 modulates SCAP osteogenic differentiation via interaction with lysine demethylase 2B(KDM2B),offering a target for therapeutic intervention.AIM To investigate the functional role and molecular mechanism of EZH2 in SCAP osteogenic differentiation.METHODS SCAPs were isolated from healthy human third molars(n=6 donors).Osteogenic differentiation was assessed via Alizarin red staining and alkaline phosphatase assays.EZH2 overexpression/knockdown models were established using lentiviral vectors.Protein interactions were analyzed by co-immunoprecipitation,transcriptomic changes via microarray(Affymetrix platform),and chromatin binding by chromatin immunoprecipitation-quantitative polymerase chain reaction.In vivo bone formation was evaluated in immunodeficient mice(n=8/group)transplanted with SCAPs-hydroxyapatite scaffolds.Data were analyzed using Student’s t-test and ANOVA.RESULTS EZH2 overexpression increased osteogenic markers and mineralized nodule formation.In vivo,EZH2-overexpressing SCAPs generated 10%more bone/dentin-like tissue.Co-immunoprecipitation confirmed EZH2-KDM2B interaction,and peptide-mediated disruption of this binding enhanced osteogenesis.Transcriptome analysis identified 1648 differentially expressed genes(971 upregulated;677 downregulated),with pathway enrichment in Wnt/β-catenin signaling.CONCLUSION EZH2 promotes SCAP osteogenesis via antagonistic interaction with KDM2B,and targeted disruption of this axis offers a translatable strategy for bone regeneration.展开更多
Hypertrophic cardiomyopathy(HCM)is a primary myocardial disease characterized by myocardial hypertrophy,excluding other cardiovascular or systemic/metabolic causes of ventricular wall thickening.Apical hypertrophic ca...Hypertrophic cardiomyopathy(HCM)is a primary myocardial disease characterized by myocardial hypertrophy,excluding other cardiovascular or systemic/metabolic causes of ventricular wall thickening.Apical hypertrophic cardiomyopathy(ApHCM)represents a special form of ventricular hypertrophy predominantly affecting the left ventricular apex below the papillary muscles,typically without significant left ventricular outflow tract obstruction.[1,2]ApHCM often coexists with mild coronary artery abnormalities,[3]and reports of acute myocardial infarction with coronary artery stenosis in ApHCM or HCM patients are uncommon.展开更多
The disparity in the transfer of carriers(electrons/mass)during the reaction in zinc-air batteries(ZABs)results in sluggish kinetics of the oxygen reduction reaction(ORR)and oxygen evolution reaction(OER),along with e...The disparity in the transfer of carriers(electrons/mass)during the reaction in zinc-air batteries(ZABs)results in sluggish kinetics of the oxygen reduction reaction(ORR)and oxygen evolution reaction(OER),along with elevated overpotentials,thereby imposing additional constraints on its utilization.Therefore,the pre-design and target-development of inexpensive,high-performance,and long-term stable bifunctional catalysts are urgently needed.In this work,an apically guiding dual-functional electrocatalyst(Ag-FeN_(x)-N-C)was prepared,in which a hierarchical porous nitrogen-doped carbon with three-dimensional(3D)hollow star-shaped structure is used as a substrate and high-conductivity Ag nanoparticles are coupled with iron nitride(FeN_(x))nanoparticles.Theoretical calculations indicate that the Mott-Schottky heterojunction as an inherent electric field comes from the two-phase bound of Ag and FeN_(x),of which electron accumulation in the FeN_(x)phase region and electron depletion in the Ag phase region promote orientated-guiding charge migration.The effective modulation of local electronic structures felicitously reforms the d-band electron-group distribution,and intellectually tunes the masstransfer reaction energy barriers for both ORR/OER.Additionally,the hollow star-s haped hierarchical porous structure provides an apical region for fast mass transfer.Experimental results show that the halfwave potential for ORR is 0.914 V,and the overpotential for OER is only 327 mV at 10 mA cm^(-2).A rechargeable ZAB with Ag-FeN_(x)-N-C as the air cathode demonstrates long-term cycling performance exceeding 1500 cycles(500 h),with a power density of 180 mW cm^(-2).Moreover,when employing AgFeN_(x)-N-C as the air cathode,flexible ZABs demonstrate a notable open-circuit voltage of 1.42 V and achieve a maximum power density of 65.6 mW cm^(-2).Ag-FeN_(x)-N-C shows guiding electron/mass transfer route and apical reaction microenvironment for the electrocatalyst architecture in the exploration prospects of ZABs.展开更多
BACKGROUND Radicular cyst is a lesion of odontogenic origin that arises from epithelial remains due to periapical periodontitis caused by inflammatory reactions generated at the apex of affected teeth with infected or...BACKGROUND Radicular cyst is a lesion of odontogenic origin that arises from epithelial remains due to periapical periodontitis caused by inflammatory reactions generated at the apex of affected teeth with infected or necrotic pulps.The therapeutic mana gement of radicular cysts is controversial.There is only one case report of enucleation of a radicular cyst managed with microsurgery and apicoectomy,but without the use of the guided tissue regeneration(GTR)technique in the same surgical procedure.The present clinical case describes the management of a radicular cyst with microsurgical approach,performance of an apicoectomy of the tooth associated with the entity,application of GTR technique,use of a resorbable membrane of type I bovine collagen,and bovine xenograft.CASE SUMMARY A 68-year-old patient presented with a radicular cyst from an upper lateral incisor.The microsurgical management used was aimed at enucleating the chemical membrane,performing apicoectomy of the tooth along with careful and precise retrograde filling,and implementing GTR technique using a resorbable collagen membrane and bovine xenograft.The diagnosis of radicular cyst was confirmed using histopathological analysis.The patient underwent follow-up evaluations at 10 and 30 d postoperatively.At 4 months postoperative evaluation,she remained asymptomatic,and radiographs showed significant periapical healing with adequate bone formation.CONCLUSION These results suggest that microsurgical management using the GTR technique with collagen membrane and xenograft,contributes to bone regeneration.展开更多
Introduction: Pheochromocytoma is a rare cause of secondary arterial hypertension whose clinical presentation can be multifaceted. In particular, it may be revealed or complicated by cardiovascular manifestations inde...Introduction: Pheochromocytoma is a rare cause of secondary arterial hypertension whose clinical presentation can be multifaceted. In particular, it may be revealed or complicated by cardiovascular manifestations independent of hypertension. These include Tako-Tsubo cardiomyopathy, an acute reversible dyskinetic cardiomyopathy associated with ballooning of the left ventricular apex. Observation: We present the case of a 32-year-old woman, diabetic for 2 years. Her history included untreated labile hypertension and emotional stress. She was admitted to a cardiac intensive care unit for left heart failure. Paraclinical investigations confirmed the diagnosis of Tako-Tsubo cardiomyopathy induced by pheochromocytoma. After a few days of medical treatment in the ICU, the outcome was favorable, with well-compensated heart failure, stable hemodynamics and restoration of left ventricular function. Conclusion: This observation raises the issue of delayed diagnosis of a pheochromocytoma revealed by a TTC. Despite its spectacular initial presentation, the evolution of the latter was rather favorable under appropriate treatment.展开更多
Objective:To observe the effectiveness and safety of one-time endodontics in the treatment of chronic apical periodontitis with sinus tract in pediatric deciduous teeth.Methods:109 cases of children with chronic apica...Objective:To observe the effectiveness and safety of one-time endodontics in the treatment of chronic apical periodontitis with sinus tract in pediatric deciduous teeth.Methods:109 cases of children with chronic apical periodontitis with sinus tract in the deciduous teeth treated in our hospital from January 2022 to December 2023 were selected and grouped by the randomized numerical table method,with 54 cases in the experimental group and 55 cases in the control group.The experimental group was treated with one-time endodontics and the control group was treated with conventional endodontics.Results:After the treatment,the total effective rate of treatment was higher in the experimental group than in the control group(P<0.05);the incidence of adverse events was lower in the experimental group than in the control group(P<0.05);the satisfaction of the children's family members was higher in the experimental group than in the control group(P<0.05);the pain duration was lower in the experimental group than in the control group(P<0.05).Conclusion:In the experimental group,children with chronic apical periodontitis with sinus tract of the deciduous teeth were given one-time endodontic treatment,and the results of its implementation were relatively good.展开更多
A series of new cognitions on the morphogenesis of maize ( Zea mays L.) embryo have been obtained with scanning electron microscopy and semi-thin section techniques. 1. The proembryo. The proembryo from zygotic cell d...A series of new cognitions on the morphogenesis of maize ( Zea mays L.) embryo have been obtained with scanning electron microscopy and semi-thin section techniques. 1. The proembryo. The proembryo from zygotic cell divisions may be divided into three parts: proper, hypoblast and suspensor. The suspensor is short and small, and only exists transiently. As to the hypoblast there is a growth belt, which promotes elongation of the hypoblast. Eventually the upper portion of the hypoblast contributes to the formation of the coleorhiza and the remainder dries up, sticking to the end of the coleorhiza. 2. The maize embryo possesses dorsiventrality and cotyledon dimorphism. During early proembryo stage, the dorsiventrality appears in the proper of the embryo. On the ventral side, the cells are small with dense cytoplasm and few vacuoles. On the dorsal side, the cells are larger with lower cytoplasmic density and have more vacuoles. During later proembryo stage, the proper develops into two parts: the ventrum and the dorsurn. The ventrum rises up from the center of the ventral side. The dorsurn is composed of the marginal area of the ventral side and the whole dorsal side of the proper. During young embryo development, the ventrum differentiates into the coleoptile, apical meristem, hypocotyl, radicle and the main part of the coleorhiza. What is more important, the emergence of coleoptile primordium and radicular initials occur at the axis of the proper, then the coleoptile primordium expands from its two ends toward left and right to form a ring, and the endogenous radicular initials expand in all directions to form a conical radicular tip. All these morphogenetic activities of the ventrum follow a bilateral symmetrical pattern. The dorsurn forms the scutellum. primordium. Then the scutellum primordium, expands rapidly toward the left, right, front and back, while thickening itself, so as to make all components originating from the ventrum become hidden in the longitudinal groove of the scutellum. Lastly, the left and right lateral scales emerge from the edges of the longitudinal groove and expand toward the central line of the axis. As a consequence, morphologically, the bilateral symmetry of the ventral side of the embryo is revealed entirely. Morphogenetically, the coleoptile primordium and apical meristem in maize are similar to the coleoptile (apical cotyledon) and apex formation of the nice embryo, so the coleoptile of the maize embryo can also be considered as an apical cotyledon. The scutellum is a lateral cotyledon. These dimorphic cotyledons of the maize embryo originate from the dorsiventrality of the proper. 3. The true morphological structure of the maize embryo is recognized and its developmental stages are established. A maize embryo is a hypocotyl, in which the apical part is the shoot apex (or plumule) with the coleoptile, the central part consists mainly of the hypocotyl with a lateral cotyledon (scutellum), and the basal part is the radicle with coleorhiza. The left and right lateral scales derived from the scutellum overlap at the ventral side, leaving only two little pores at both ends of the seam from which the coleoptile and coleorhiza can be seen. The four sequential stages of maize embryonic development are as follows: (1) proembryo, stage. This stage covers a period from zygotic cell division to the appearance of the dorsum and ventrum. (2) ventrum rapid differentiation stage. (3) scutellum rapid expansion stage. (4) lateral scale development stage (or embryonic envelope formation stage). 4. To obtain a median longitudinal section perpendicular to the ventral surface is crucial for recognizing the genuine morphological structure of the maize embryo.展开更多
It has been generally held in botany that Oryza sativa L. is a monocotyledon. Based on studies of rice embryo development we confirmed that rice embryo has two dimorphic cotyledons rather than just one cotyledo...It has been generally held in botany that Oryza sativa L. is a monocotyledon. Based on studies of rice embryo development we confirmed that rice embryo has two dimorphic cotyledons rather than just one cotyledon. In the present study we attempt to know if the morphology of embryos in other species of Oryza differs from O. sativa and if these embryos have dimorphic cotyledon. Two types of embryo structures were observed in 22 species and/or subspecies of genus Oryza under the scanning electron microscope. Type 1, the O.sativa type, which is characterized by ventral scale and lateral scales, was found in 16 species. Type 2, the O. meyeriana (Zoll. et Mor. ex Steud.) Baill. ssp. tuberculata W. C. Wu et Y. G. Lu, G. C. Wang type, with no ventral scale and lateral scales, was found in 6 species and subspecies. The embryogenic process of O.sativa and O.meyeriana sub. tuberculata showed that the scutellum primordium, coleorhiza primordium, coleoptile primordium and shoot apical meristem directly differentiate from proembryo. The former two later develop into the embryo envelope, which is the outside cotyledon; the coleoptile primordium develops into the coleoptile with the shape of inverted empty cone surrounding and covering the growth cone, which is the apical cotyledon. Both types of rice embryos have dimorphic cotyledons. The structural difference between them is that the scutellum primordium of the young embryo in type 2 does not differentiate ventral scale and lateral scales while the embryo of type 1 does. The dimorphic cotyledons of embryo of Oryza plants originate from the dorsiventrality of proembryo.展开更多
Orbital inflammatory disease(OID) represents a collec tion of inflammatory conditions affecting the orbit. OID is a diagnosis of exclusion, with the differential diagno sis including infection, systemic inflammatory c...Orbital inflammatory disease(OID) represents a collec tion of inflammatory conditions affecting the orbit. OID is a diagnosis of exclusion, with the differential diagno sis including infection, systemic inflammatory conditions and neoplasms, among other conditions. Inflammatory conditions in OID include dacryoadenitis, myositis, cel lulitis, optic perineuritis, periscleritis, orbital apicitis, and a focal mass. Sclerosing orbital inflammation is a rare condition with a chronic, indolent course involving dense fibrosis and lymphocytic infiltrate. Previously though to be along the spectrum of OID, it is now considered a distinct pathologic entity. Imaging plays an importan role in elucidating any underlying etiology behind orbita inflammation and is critical for ruling out other condi tions prior to a definitive diagnosis of OID. In this re view, we will explore the common sites of involvemen by OID and discuss differential diagnosis by site and key imaging findings for each condition.展开更多
Apical dominance is a phenomenon that the growth of axillary meristems is inhibited by the primary shoot or inflorescence. Recent researches have begun to reveal the molecular mechanisms of apical dominance by isolati...Apical dominance is a phenomenon that the growth of axillary meristems is inhibited by the primary shoot or inflorescence. Recent researches have begun to reveal the molecular mechanisms of apical dominance by isolating and identifying mutants with altered apical dominance. Here we report isolation of a bushy and dwarf 1 (bud1) mutant from Arabidopsis thaliana L. through a T-DNA tagging approach. The phenotypes of bul1 plants include loss of apical dominance, reduced plant size and dwarfism, suggesting that the bud1 mutant may be involved in auxin metabolism, transport or signalling. Using a reporter gene driven by an auxin-responsive promoter, we found that the expression pattern of auxin response element was altered in bud1. The auxin sensitivity and transport assay indicates that these two processes are normal in bud1. These results suggest that the bud1 phenotypes may result from an alteration in auxin metabolism. Genetic analysis demonstrates that bud1 is a semidominant mutant and cosegregates with a T-DNA insertion, which indicates that BUD1 gene could be cloned by iPCR approach.展开更多
基金supported by grants FONDECYT 1180850 and 1231757 to RM.
文摘The factors affecting the behavior of non-specialized nectar-feeding passerines have received little attention in the literature on plant-pollinator interactions. Puya chilensis (Bromeliaceae) has sterile branch apices that project outward from the inflorescence. In this study, we evaluate the functional role of sterile apices as support systems for bird foraging behavior. We recorded bird visitation and flower probing in the presence and absence of sterile branches during the spring seasons of 2021 and 2024. The results revealed that experimental plants with excised branches received fewer bird visits and flower probings than control plants, indicating that sterile branches play an important role in the nectar-feeding behavior of passerine birds in P. chilensis.
文摘Epigenetics is the discipline of regulating cellular activity through chemical modification or modulation of noncoding RNAs without altering the nucleotide sequence.Studies on this topic include the exploration of DNA methylation,histone modification,noncoding RNA regulation,and chromatin remodeling.Derived from the apical tissues of young permanent teeth,stem cells from apical papilla are odontogenic adult stem cells with high proliferation,self-renewal capacity,and differentiation potential.These cells play crucial roles in root formation and development.This article focuses on the two epigenetic regulatory mechanisms of histone modifications and non-coding RNA.This review summarizes,generalizes,and evaluates the status of research on the epigenetic regulation of the multidirectional differentiation of stem cells from the apical papilla,aiming to explore the mechanisms underlying the multidirectional differentiation process of these stem cells.
基金funded by E Fund Congenital Heart Disease Medical Talent Cultivation and Education Fund,grant number 2023QT0009the Science and Technology Planning Project of Guangdong Province,grant number 2023B03J1255.
文摘Comments Ebstein's Anomaly(EA)is a rare congenital heart disease(CHD)with an incidence of approximately 1 in 20,000.The pathognomonic feature involves apical displacement of the septal and posterior leaflets,resulting in valvular insufficiency and right ventricular(RV)remodeling.Untreated patients exhibit a cumulative mortality rate of up to 25% within the first decade,with heart failure(HF)and arrhythmias constituting the predominant causes of death.Current guidelines suggest that asymptomatic patients with accessory pathways may benefit from prophylactic ablation,though robust evidence specific to EA remains limited[1-3].
基金Supported by National Key Research and Development Program,No.2022YFA1104401Beijing Natural Science Foundation,No.7222075+1 种基金CAMS Innovation Fund for Medical Sciences,No.2019RU020Innovation Research Team Project of Beijing Stomatological Hospital,No.CXTD202204.
文摘BACKGROUND Stem cells from apical papilla(SCAPs)represent promising candidates for bone regenerative therapies due to their osteogenic potential.However,enhancing their differentiation capacity remains a critical challenge.Enhancer of zeste homolog 2(EZH2),a histone H3 lysine 27 methyltransferase,regulates osteogenesis through epigenetic mechanisms,but its role in SCAPs remains unclear.We hypothesized that EZH2 modulates SCAP osteogenic differentiation via interaction with lysine demethylase 2B(KDM2B),offering a target for therapeutic intervention.AIM To investigate the functional role and molecular mechanism of EZH2 in SCAP osteogenic differentiation.METHODS SCAPs were isolated from healthy human third molars(n=6 donors).Osteogenic differentiation was assessed via Alizarin red staining and alkaline phosphatase assays.EZH2 overexpression/knockdown models were established using lentiviral vectors.Protein interactions were analyzed by co-immunoprecipitation,transcriptomic changes via microarray(Affymetrix platform),and chromatin binding by chromatin immunoprecipitation-quantitative polymerase chain reaction.In vivo bone formation was evaluated in immunodeficient mice(n=8/group)transplanted with SCAPs-hydroxyapatite scaffolds.Data were analyzed using Student’s t-test and ANOVA.RESULTS EZH2 overexpression increased osteogenic markers and mineralized nodule formation.In vivo,EZH2-overexpressing SCAPs generated 10%more bone/dentin-like tissue.Co-immunoprecipitation confirmed EZH2-KDM2B interaction,and peptide-mediated disruption of this binding enhanced osteogenesis.Transcriptome analysis identified 1648 differentially expressed genes(971 upregulated;677 downregulated),with pathway enrichment in Wnt/β-catenin signaling.CONCLUSION EZH2 promotes SCAP osteogenesis via antagonistic interaction with KDM2B,and targeted disruption of this axis offers a translatable strategy for bone regeneration.
文摘Hypertrophic cardiomyopathy(HCM)is a primary myocardial disease characterized by myocardial hypertrophy,excluding other cardiovascular or systemic/metabolic causes of ventricular wall thickening.Apical hypertrophic cardiomyopathy(ApHCM)represents a special form of ventricular hypertrophy predominantly affecting the left ventricular apex below the papillary muscles,typically without significant left ventricular outflow tract obstruction.[1,2]ApHCM often coexists with mild coronary artery abnormalities,[3]and reports of acute myocardial infarction with coronary artery stenosis in ApHCM or HCM patients are uncommon.
基金the financial support of the National Natural Science Foundation of China(52002079,22378074,22179025 and U20A20340)the Guangdong Basic and Applied Basic Research Foundation(2022A1515140085)+2 种基金the Research Fund Program of Guangdong Provincial Key Laboratory of Fuel Cell Technology(FC202209)the Guangzhou Hongmian Project(HMJH-20200012)the Foshan Introducing Innovative and Entrepreneurial Teams(1920001000108)。
文摘The disparity in the transfer of carriers(electrons/mass)during the reaction in zinc-air batteries(ZABs)results in sluggish kinetics of the oxygen reduction reaction(ORR)and oxygen evolution reaction(OER),along with elevated overpotentials,thereby imposing additional constraints on its utilization.Therefore,the pre-design and target-development of inexpensive,high-performance,and long-term stable bifunctional catalysts are urgently needed.In this work,an apically guiding dual-functional electrocatalyst(Ag-FeN_(x)-N-C)was prepared,in which a hierarchical porous nitrogen-doped carbon with three-dimensional(3D)hollow star-shaped structure is used as a substrate and high-conductivity Ag nanoparticles are coupled with iron nitride(FeN_(x))nanoparticles.Theoretical calculations indicate that the Mott-Schottky heterojunction as an inherent electric field comes from the two-phase bound of Ag and FeN_(x),of which electron accumulation in the FeN_(x)phase region and electron depletion in the Ag phase region promote orientated-guiding charge migration.The effective modulation of local electronic structures felicitously reforms the d-band electron-group distribution,and intellectually tunes the masstransfer reaction energy barriers for both ORR/OER.Additionally,the hollow star-s haped hierarchical porous structure provides an apical region for fast mass transfer.Experimental results show that the halfwave potential for ORR is 0.914 V,and the overpotential for OER is only 327 mV at 10 mA cm^(-2).A rechargeable ZAB with Ag-FeN_(x)-N-C as the air cathode demonstrates long-term cycling performance exceeding 1500 cycles(500 h),with a power density of 180 mW cm^(-2).Moreover,when employing AgFeN_(x)-N-C as the air cathode,flexible ZABs demonstrate a notable open-circuit voltage of 1.42 V and achieve a maximum power density of 65.6 mW cm^(-2).Ag-FeN_(x)-N-C shows guiding electron/mass transfer route and apical reaction microenvironment for the electrocatalyst architecture in the exploration prospects of ZABs.
文摘BACKGROUND Radicular cyst is a lesion of odontogenic origin that arises from epithelial remains due to periapical periodontitis caused by inflammatory reactions generated at the apex of affected teeth with infected or necrotic pulps.The therapeutic mana gement of radicular cysts is controversial.There is only one case report of enucleation of a radicular cyst managed with microsurgery and apicoectomy,but without the use of the guided tissue regeneration(GTR)technique in the same surgical procedure.The present clinical case describes the management of a radicular cyst with microsurgical approach,performance of an apicoectomy of the tooth associated with the entity,application of GTR technique,use of a resorbable membrane of type I bovine collagen,and bovine xenograft.CASE SUMMARY A 68-year-old patient presented with a radicular cyst from an upper lateral incisor.The microsurgical management used was aimed at enucleating the chemical membrane,performing apicoectomy of the tooth along with careful and precise retrograde filling,and implementing GTR technique using a resorbable collagen membrane and bovine xenograft.The diagnosis of radicular cyst was confirmed using histopathological analysis.The patient underwent follow-up evaluations at 10 and 30 d postoperatively.At 4 months postoperative evaluation,she remained asymptomatic,and radiographs showed significant periapical healing with adequate bone formation.CONCLUSION These results suggest that microsurgical management using the GTR technique with collagen membrane and xenograft,contributes to bone regeneration.
文摘Introduction: Pheochromocytoma is a rare cause of secondary arterial hypertension whose clinical presentation can be multifaceted. In particular, it may be revealed or complicated by cardiovascular manifestations independent of hypertension. These include Tako-Tsubo cardiomyopathy, an acute reversible dyskinetic cardiomyopathy associated with ballooning of the left ventricular apex. Observation: We present the case of a 32-year-old woman, diabetic for 2 years. Her history included untreated labile hypertension and emotional stress. She was admitted to a cardiac intensive care unit for left heart failure. Paraclinical investigations confirmed the diagnosis of Tako-Tsubo cardiomyopathy induced by pheochromocytoma. After a few days of medical treatment in the ICU, the outcome was favorable, with well-compensated heart failure, stable hemodynamics and restoration of left ventricular function. Conclusion: This observation raises the issue of delayed diagnosis of a pheochromocytoma revealed by a TTC. Despite its spectacular initial presentation, the evolution of the latter was rather favorable under appropriate treatment.
文摘Objective:To observe the effectiveness and safety of one-time endodontics in the treatment of chronic apical periodontitis with sinus tract in pediatric deciduous teeth.Methods:109 cases of children with chronic apical periodontitis with sinus tract in the deciduous teeth treated in our hospital from January 2022 to December 2023 were selected and grouped by the randomized numerical table method,with 54 cases in the experimental group and 55 cases in the control group.The experimental group was treated with one-time endodontics and the control group was treated with conventional endodontics.Results:After the treatment,the total effective rate of treatment was higher in the experimental group than in the control group(P<0.05);the incidence of adverse events was lower in the experimental group than in the control group(P<0.05);the satisfaction of the children's family members was higher in the experimental group than in the control group(P<0.05);the pain duration was lower in the experimental group than in the control group(P<0.05).Conclusion:In the experimental group,children with chronic apical periodontitis with sinus tract of the deciduous teeth were given one-time endodontic treatment,and the results of its implementation were relatively good.
文摘A series of new cognitions on the morphogenesis of maize ( Zea mays L.) embryo have been obtained with scanning electron microscopy and semi-thin section techniques. 1. The proembryo. The proembryo from zygotic cell divisions may be divided into three parts: proper, hypoblast and suspensor. The suspensor is short and small, and only exists transiently. As to the hypoblast there is a growth belt, which promotes elongation of the hypoblast. Eventually the upper portion of the hypoblast contributes to the formation of the coleorhiza and the remainder dries up, sticking to the end of the coleorhiza. 2. The maize embryo possesses dorsiventrality and cotyledon dimorphism. During early proembryo stage, the dorsiventrality appears in the proper of the embryo. On the ventral side, the cells are small with dense cytoplasm and few vacuoles. On the dorsal side, the cells are larger with lower cytoplasmic density and have more vacuoles. During later proembryo stage, the proper develops into two parts: the ventrum and the dorsurn. The ventrum rises up from the center of the ventral side. The dorsurn is composed of the marginal area of the ventral side and the whole dorsal side of the proper. During young embryo development, the ventrum differentiates into the coleoptile, apical meristem, hypocotyl, radicle and the main part of the coleorhiza. What is more important, the emergence of coleoptile primordium and radicular initials occur at the axis of the proper, then the coleoptile primordium expands from its two ends toward left and right to form a ring, and the endogenous radicular initials expand in all directions to form a conical radicular tip. All these morphogenetic activities of the ventrum follow a bilateral symmetrical pattern. The dorsurn forms the scutellum. primordium. Then the scutellum primordium, expands rapidly toward the left, right, front and back, while thickening itself, so as to make all components originating from the ventrum become hidden in the longitudinal groove of the scutellum. Lastly, the left and right lateral scales emerge from the edges of the longitudinal groove and expand toward the central line of the axis. As a consequence, morphologically, the bilateral symmetry of the ventral side of the embryo is revealed entirely. Morphogenetically, the coleoptile primordium and apical meristem in maize are similar to the coleoptile (apical cotyledon) and apex formation of the nice embryo, so the coleoptile of the maize embryo can also be considered as an apical cotyledon. The scutellum is a lateral cotyledon. These dimorphic cotyledons of the maize embryo originate from the dorsiventrality of the proper. 3. The true morphological structure of the maize embryo is recognized and its developmental stages are established. A maize embryo is a hypocotyl, in which the apical part is the shoot apex (or plumule) with the coleoptile, the central part consists mainly of the hypocotyl with a lateral cotyledon (scutellum), and the basal part is the radicle with coleorhiza. The left and right lateral scales derived from the scutellum overlap at the ventral side, leaving only two little pores at both ends of the seam from which the coleoptile and coleorhiza can be seen. The four sequential stages of maize embryonic development are as follows: (1) proembryo, stage. This stage covers a period from zygotic cell division to the appearance of the dorsum and ventrum. (2) ventrum rapid differentiation stage. (3) scutellum rapid expansion stage. (4) lateral scale development stage (or embryonic envelope formation stage). 4. To obtain a median longitudinal section perpendicular to the ventral surface is crucial for recognizing the genuine morphological structure of the maize embryo.
文摘It has been generally held in botany that Oryza sativa L. is a monocotyledon. Based on studies of rice embryo development we confirmed that rice embryo has two dimorphic cotyledons rather than just one cotyledon. In the present study we attempt to know if the morphology of embryos in other species of Oryza differs from O. sativa and if these embryos have dimorphic cotyledon. Two types of embryo structures were observed in 22 species and/or subspecies of genus Oryza under the scanning electron microscope. Type 1, the O.sativa type, which is characterized by ventral scale and lateral scales, was found in 16 species. Type 2, the O. meyeriana (Zoll. et Mor. ex Steud.) Baill. ssp. tuberculata W. C. Wu et Y. G. Lu, G. C. Wang type, with no ventral scale and lateral scales, was found in 6 species and subspecies. The embryogenic process of O.sativa and O.meyeriana sub. tuberculata showed that the scutellum primordium, coleorhiza primordium, coleoptile primordium and shoot apical meristem directly differentiate from proembryo. The former two later develop into the embryo envelope, which is the outside cotyledon; the coleoptile primordium develops into the coleoptile with the shape of inverted empty cone surrounding and covering the growth cone, which is the apical cotyledon. Both types of rice embryos have dimorphic cotyledons. The structural difference between them is that the scutellum primordium of the young embryo in type 2 does not differentiate ventral scale and lateral scales while the embryo of type 1 does. The dimorphic cotyledons of embryo of Oryza plants originate from the dorsiventrality of proembryo.
文摘Orbital inflammatory disease(OID) represents a collec tion of inflammatory conditions affecting the orbit. OID is a diagnosis of exclusion, with the differential diagno sis including infection, systemic inflammatory conditions and neoplasms, among other conditions. Inflammatory conditions in OID include dacryoadenitis, myositis, cel lulitis, optic perineuritis, periscleritis, orbital apicitis, and a focal mass. Sclerosing orbital inflammation is a rare condition with a chronic, indolent course involving dense fibrosis and lymphocytic infiltrate. Previously though to be along the spectrum of OID, it is now considered a distinct pathologic entity. Imaging plays an importan role in elucidating any underlying etiology behind orbita inflammation and is critical for ruling out other condi tions prior to a definitive diagnosis of OID. In this re view, we will explore the common sites of involvemen by OID and discuss differential diagnosis by site and key imaging findings for each condition.
文摘Apical dominance is a phenomenon that the growth of axillary meristems is inhibited by the primary shoot or inflorescence. Recent researches have begun to reveal the molecular mechanisms of apical dominance by isolating and identifying mutants with altered apical dominance. Here we report isolation of a bushy and dwarf 1 (bud1) mutant from Arabidopsis thaliana L. through a T-DNA tagging approach. The phenotypes of bul1 plants include loss of apical dominance, reduced plant size and dwarfism, suggesting that the bud1 mutant may be involved in auxin metabolism, transport or signalling. Using a reporter gene driven by an auxin-responsive promoter, we found that the expression pattern of auxin response element was altered in bud1. The auxin sensitivity and transport assay indicates that these two processes are normal in bud1. These results suggest that the bud1 phenotypes may result from an alteration in auxin metabolism. Genetic analysis demonstrates that bud1 is a semidominant mutant and cosegregates with a T-DNA insertion, which indicates that BUD1 gene could be cloned by iPCR approach.
