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1.
Pflege ; 37(4): 179-186, 2024 08.
Artigo em Alemão | MEDLINE | ID: mdl-38319307

RESUMO

Critical care nurses' decision-making regarding verification of blindly inserted gastric tubes: A cross-sectional questionnaire study Abstract: Background: The placement and verification of the correct position of blindly applied gastric tubes is regularly performed by nurses in clinical practice. International guidelines recommend a radiological verification as a "first-line" method or if pH measurement is not possible. For Germany, neither evidence-based recommendations nor current data are available. Question: Which methods are used by nurses in German intensive care units for verification of the correct position of blindly applied gastric tubes and how do they assess the reliability of different methods? Methods: Multicenter questionnaire survey. Intensive care units in a non-probability, citeria-based sampling of hospitals in and around Cologne, Germany were included. One nurse was included per participating ward. Analyses were mostly descriptive. Results: In 22 hospitals, 38 wards agreed to participate and 32 (84%) responded to the survey. Auscultation of the upper abdomen with simultaneous air insufflation and aspiration of gastric secretions are frequently used methods for determining the position of gastric tubes. Participants consider auscultation, aspiration of gastric secretions, and radiological control as reliable methods. Conclusions: The findings are in contrast to international recommendations and support the need for evidence-based best practice recommendations and training. Likewise, there is a need for research on feasible bedside methods.


Assuntos
Enfermagem de Cuidados Críticos , Intubação Gastrointestinal , Humanos , Estudos Transversais , Inquéritos e Questionários , Enfermagem de Cuidados Críticos/normas , Intubação Gastrointestinal/enfermagem , Alemanha , Tomada de Decisão Clínica , Unidades de Terapia Intensiva , Nutrição Enteral/enfermagem
2.
Cancers (Basel) ; 15(22)2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-38001587

RESUMO

Rectal cancer invading adjacent organs (T4) and locally recurrent rectal cancer (LRRC) pose a special challenge for surgical resection. We investigate the diagnostic performance of MRI and the results that can be achieved with MRI-guided surgery. All consecutive patients who underwent MRI-based multivisceral resection for T4 rectal adenocarcinoma or LRRC between 2005 and 2019 were included. Pelvic MRI findings were reviewed according to a seven-compartment staging system and correlated with histopathology. Outcomes were investigated by comparing T4 tumors and LRRC with respect to cause-specific survival in uni- and multivariate analysis. We identified 48 patients with T4 tumors and 28 patients with LRRC. Overall, 529 compartments were assessed with an accuracy of 81.7%, a sensitivity of 88.6%, and a specificity of 79.2%. Understaging was as low as 3.0%, whereas overstaging was 15.3%. The median number of resected compartments was 3 (interquartile range 3-4) for T4 tumors and 4 (interquartile range 3-5) for LRRC (p = 0.017). In 93.8% of patients with T4 tumors, a histopathologically complete (R0(local)-) resection could be achieved compared to 57.1% in LRRC (p < 0.001). Five-year overall survival for patients with T4 tumors was 53.3% vs. 32.1% for LRRC (p = 0.085). R0-resection and M0-category emerged as independent prognostic factors, whereas the number of resected compartments was not associated with prognosis in multivariate analysis. MRI predicts compartment involvement with high accuracy and especially avoids understaging. Surgery based on MRI yields excellent loco-regional results for T4 tumors and good results for LRRC. The number of resected compartments is not independently associated with prognosis, but R0-resection remains the crucial surgical factor.

3.
Curr Biol ; 31(9): R449-R451, 2021 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-33974874

RESUMO

PIN-FORMED (PIN) polar protein localization directs transport of the growth and developmental regulator auxin in plants. Once established after cytokinesis, PIN polarity requires maintenance. Now, direct interactions between PIN, MAB4/MEL and PID proteins suggest self-reinforced maintenance of PIN polarity through limiting lateral diffusion.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Ácidos Indolacéticos , Proteínas de Membrana Transportadoras/metabolismo , Transporte Proteico
4.
Int J Mol Sci ; 22(1)2021 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-33406774

RESUMO

Plant membrane sterol composition has been reported to affect growth and gravitropism via polar auxin transport and auxin signaling. However, as to whether sterols influence auxin biosynthesis has received little attention. Here, by using the sterol biosynthesis mutant cyclopropylsterol isomerase1-1 (cpi1-1) and sterol application, we reveal that cycloeucalenol, a CPI1 substrate, and sitosterol, an end-product of sterol biosynthesis, antagonistically affect auxin biosynthesis. The short root phenotype of cpi1-1 was associated with a markedly enhanced auxin response in the root tip. Both were neither suppressed by mutations in polar auxin transport (PAT) proteins nor by treatment with a PAT inhibitor and responded to an auxin signaling inhibitor. However, expression of several auxin biosynthesis genes TRYPTOPHAN AMINOTRANSFERASE OF ARABIDOPSIS1 (TAA1) was upregulated in cpi1-1. Functionally, TAA1 mutation reduced the auxin response in cpi1-1 and partially rescued its short root phenotype. In support of this genetic evidence, application of cycloeucalenol upregulated expression of the auxin responsive reporter DR5:GUS (ß-glucuronidase) and of several auxin biosynthesis genes, while sitosterol repressed their expression. Hence, our combined genetic, pharmacological, and sterol application studies reveal a hitherto unexplored sterol-dependent modulation of auxin biosynthesis during Arabidopsis root elongation.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Ácidos Indolacéticos/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Esteróis/farmacologia , Arabidopsis/efeitos dos fármacos , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Transporte Biológico , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo
5.
Geburtshilfe Frauenheilkd ; 79(9): 959-968, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31523096

RESUMO

Introduction Patients who suffer from pelvic organ prolapse can experience severe limitations in their quality of life. To improve the quality of life of women affected and achieve a stable reconstruction, surgical therapy is often indispensable. In conventional prolapse surgery, the rate of recurrence is high. For this reason, alloplastic mesh has been implanted increasingly in recent years to reconstruct the anatomy of the pelvic floor organs. Even if the anatomical result can be significantly improved as a result, the mesh-induced complications have been the subject of controversial discussion. In this national, multicentre study, the quality of life, anatomical result as well as the rate of complications following the implantation of an alloplastic mesh for the correction of a cystocele were investigated. Method Fifty-four patients with symptomatic ≥ grade II were included in this prospective, national, multicentre study. The study participants were implanted with a titanised polypropylene mesh (TiLOOP ® PRO A, pfm medical ag). The follow-up observation period was 12 months. Primary as well as repeat procedures were taken into account. The anatomic result of the pelvic floor reconstruction was quantified using the POP-Q system. Data on quality of life and sexuality were collected using validated questionnaires. All complications which occurred were documented and evaluated by an independent committee. Results On average, the patients were in line with the census. An improvement in quality of life was able to be determined during the study in all domains investigated (p < 0.001, Wilcoxon test). Minus incorrect entries and incorrect reports, a total of 19 reports of adverse events in 15 patients were evaluated by the end of the study. The rate of recurrence in the anterior compartment was 4.3%. Conclusion In the reconstruction of the anatomical position of the pelvic floor organs given the presence of a symptomatic cystocele, the implantation of a third-generation alloplastic mesh achieves very good results. Affected patients benefit from the anatomical stability as well as a significant improvement in quality of life, whereby the risks are justifiable.

6.
Development ; 146(5)2019 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-30770391

RESUMO

Root hairs are protrusions from root epidermal cells with crucial roles in plant soil interactions. Although much is known about patterning, polarity and tip growth of root hairs, contributions of membrane trafficking to hair initiation remain poorly understood. Here, we demonstrate that the trans-Golgi network-localized YPT-INTERACTING PROTEIN 4a and YPT-INTERACTING PROTEIN 4b (YIP4a/b) contribute to activation and plasma membrane accumulation of Rho-of-plant (ROP) small GTPases during hair initiation, identifying YIP4a/b as central trafficking components in ROP-dependent root hair formation.


Assuntos
Proteínas de Arabidopsis/fisiologia , Arabidopsis/enzimologia , Genes de Plantas , Proteínas de Membrana/farmacologia , Raízes de Plantas/fisiologia , Proteínas rho de Ligação ao GTP/fisiologia , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/farmacologia , Membrana Celular/fisiologia , Genótipo , Proteínas de Membrana/genética , Proteínas Monoméricas de Ligação ao GTP/fisiologia , Mutação , Fenótipo , Transporte Proteico , Sementes , Rede trans-Golgi/fisiologia
7.
Physiol Plant ; 164(1): 17-26, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29418000

RESUMO

The plant cell wall surrounds and protects the cells. To divide, plant cells must synthesize a new cell wall to separate the two daughter cells. The cell plate is a transient polysaccharide-based compartment that grows between daughter cells and gives rise to the new cell wall. Cellulose constitutes a key component of the cell wall, and mutants with defects in cellulose synthesis commonly share phenotypes with cytokinesis-defective mutants. However, despite the importance of cellulose in the cell plate and the daughter cell wall, many open questions remain regarding the timing and regulation of cellulose synthesis during cell division. These questions represent a critical gap in our knowledge of cell plate assembly, cell division and growth. Here, we review what is known about cellulose synthesis at the cell plate and in the newly formed cross-wall and pose key questions about the molecular mechanisms that govern these processes. We further provide an outlook discussing outstanding questions and possible future directions for this field of research.


Assuntos
Celulose/metabolismo , Divisão Celular/fisiologia , Parede Celular/metabolismo , Citocinese/fisiologia , Células Vegetais/metabolismo
8.
Curr Opin Plant Biol ; 41: 46-53, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28869926

RESUMO

Plant roots control uptake of water and nutrients and cope with environmental challenges. The root epidermis provides the first selective interface for nutrient absorption, while the endodermis produces the main apoplastic diffusion barrier in the form of a structure called the Casparian strip. The positioning of root hairs on epidermal cells, and of the Casparian strip around endodermal cells, requires asymmetries along cellular axes (cell polarity). Cell polarity is termed planar polarity, when coordinated within the plane of a given tissue layer. Here, we review recent molecular advances towards understanding both the polar positioning of the proteo-lipid membrane domain instructing root hair initiation, and the cytoskeletal, trafficking and polar tethering requirements of proteins at outer or inner plasma membrane domains. Finally, we highlight progress towards understanding mechanisms of Casparian strip formation and underlying endodermal cell polarity.


Assuntos
Arabidopsis/fisiologia , Polaridade Celular , Raízes de Plantas/fisiologia , Transporte Biológico , Diferenciação Celular , Membrana Celular/metabolismo , Parede Celular/metabolismo , Citoesqueleto/metabolismo , Transporte Proteico
9.
Plant Physiol ; 176(1): 378-391, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29084900

RESUMO

Polar nuclear migration is crucial during the development of diverse eukaryotes. In plants, root hair growth requires polar nuclear migration into the outgrowing hair. However, knowledge about the dynamics and the regulatory mechanisms underlying nuclear movements in root epidermal cells remains limited. Here, we show that both auxin and Rho-of-Plant (ROP) signaling modulate polar nuclear position at the inner epidermal plasma membrane domain oriented to the cortical cells during cell elongation as well as subsequent polar nuclear movement to the outer domain into the emerging hair bulge in Arabidopsis (Arabidopsis thaliana). Auxin signaling via the nuclear AUXIN RESPONSE FACTOR7 (ARF7)/ARF19 and INDOLE ACETIC ACID7 pathway ensures correct nuclear placement toward the inner membrane domain. Moreover, precise inner nuclear placement relies on SPIKE1 Rho-GEF, SUPERCENTIPEDE1 Rho-GDI, and ACTIN7 (ACT7) function and to a lesser extent on VTI11 vacuolar SNARE activity. Strikingly, the directionality and/or velocity of outer polar nuclear migration into the hair outgrowth along actin strands also are ACT7 dependent, auxin sensitive, and regulated by ROP signaling. Thus, our findings provide a founding framework revealing auxin and ROP signaling of inner polar nuclear position with some contribution by vacuolar morphology and of actin-dependent outer polar nuclear migration in root epidermal hair cells.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimologia , Núcleo Celular/metabolismo , Polaridade Celular , Proteínas de Ligação ao GTP/metabolismo , Ácidos Indolacéticos/metabolismo , Epiderme Vegetal/citologia , Raízes de Plantas/citologia , Transdução de Sinais , Arabidopsis/citologia , Etilenos/metabolismo , Movimento , Mutação/genética , Vacúolos/metabolismo
10.
Nat Plants ; 3(11): 854-858, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29085068

RESUMO

The outermost cell layer of plant roots (epidermis) constantly encounters environmental challenges. The epidermal outer plasma membrane domain harbours the PENETRATION3 (PEN3)/ABCG36/PDR8 ATP-binding cassette transporter that confers non-host resistance to several pathogens. Here, we show that the Arabidopsis ENDOPLASMIC RETICULUM-ARRESTED PEN3 (EAP3) BTB/POZ-domain protein specifically mediates PEN3 exit from the endoplasmic reticulum and confers resistance to a root-penetrating fungus, providing prime evidence for BTB/POZ-domain protein-dependent membrane trafficking underlying disease resistance.


Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Arabidopsis/microbiologia , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Mapeamento Cromossômico , Cromossomos de Plantas , Retículo Endoplasmático/metabolismo , Proteínas de Fluorescência Verde/genética , Proteínas de Membrana/metabolismo , Mutação , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Domínios Proteicos
11.
Geburtshilfe Frauenheilkd ; 77(9): 993-1001, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28959063

RESUMO

INTRODUCTION: Pelvic organ prolapse can significantly reduce quality of life of affected women, with many cases requiring corrective surgery. The rate of recurrence is relatively high after conventional prolapse surgery. In recent years, alloplastic meshes have increasingly been implanted to stabilize the pelvic floor, which has led to considerable improvement of anatomical results. But the potential for mesh-induced risks has led to a controversial discussion on the use of surgical meshes in urogynecology. The impact of cystocele correction and implantation of an alloplastic mesh on patients' quality of life/sexuality and the long-term stability of this approach were investigated. METHOD: In a large prospective multicenter study, 289 patients with symptomatic cystocele underwent surgery with implantation of a titanized polypropylene mesh (TiLOOP ® Total 6, pfm medical ag) and followed up for 36 months. Both primary procedures and procedures for recurrence were included in the study. Anatomical outcomes were quantified using the POP-Q system. Quality of life including sexuality were assessed using the German version of the validated P-QoL questionnaire. All adverse events were assessed by an independent clinical event committee. RESULTS: Mean patient age was 67 ± 8 years. Quality of life improved significantly over the course of the study in all investigated areas, including sexuality and personal relationships (p < 0.001, Wilcoxon test). The number of adverse events which occurred in the period between 12 and 36 months after surgery was low, with just 22 events reported. The recurrence rate for the anterior compartment was 4.5%. Previous or concomitant hysterectomy increased the risk of recurrence in the posterior compartment 2.8-fold and increased the risk of erosion 2.25-fold. CONCLUSION: Cystocele correction using a 2nd generation alloplastic mesh achieved good anatomical and functional results in cases requiring stabilization of the pelvic floor and in patients with recurrence. The rate of recurrence was low, the patients' quality of life improved significantly, and the risks were acceptable.

12.
Proc Natl Acad Sci U S A ; 114(18): 4597-4602, 2017 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-28420793

RESUMO

The organic electronic ion pump (OEIP) provides flow-free and accurate delivery of small signaling compounds at high spatiotemporal resolution. To date, the application of OEIPs has been limited to delivery of nonaromatic molecules to mammalian systems, particularly for neuroscience applications. However, many long-standing questions in plant biology remain unanswered due to a lack of technology that precisely delivers plant hormones, based on cyclic alkanes or aromatic structures, to regulate plant physiology. Here, we report the employment of OEIPs for the delivery of the plant hormone auxin to induce differential concentration gradients and modulate plant physiology. We fabricated OEIP devices based on a synthesized dendritic polyelectrolyte that enables electrophoretic transport of aromatic substances. Delivery of auxin to transgenic Arabidopsis thaliana seedlings in vivo was monitored in real time via dynamic fluorescent auxin-response reporters and induced physiological responses in roots. Our results provide a starting point for technologies enabling direct, rapid, and dynamic electronic interaction with the biochemical regulation systems of plants.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Eletrônica , Ácidos Indolacéticos/farmacologia , Fenômenos Fisiológicos Vegetais/efeitos dos fármacos , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Plântula/crescimento & desenvolvimento , Arabidopsis/genética , Ácidos Indolacéticos/metabolismo , Bombas de Íon , Fenômenos Fisiológicos Vegetais/genética , Plantas Geneticamente Modificadas/genética , Plântula/genética
13.
Front Plant Sci ; 7: 1560, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27840629

RESUMO

Plant cells have two main modes of growth generating anisotropic structures. Diffuse growth where whole cell walls extend in specific directions, guided by anisotropically positioned cellulose fibers, and tip growth, with inhomogeneous addition of new cell wall material at the tip of the structure. Cells are known to regulate these processes via molecular signals and the cytoskeleton. Mechanical stress has been proposed to provide an input to the positioning of the cellulose fibers via cortical microtubules in diffuse growth. In particular, a stress feedback model predicts a circumferential pattern of fibers surrounding apical tissues and growing primordia, guided by the anisotropic curvature in such tissues. In contrast, during the initiation of tip growing root hairs, a star-like radial pattern has recently been observed. Here, we use detailed finite element models to analyze how a change in mechanical properties at the root hair initiation site can lead to star-like stress patterns in order to understand whether a stress-based feedback model can also explain the microtubule patterns seen during root hair initiation. We show that two independent mechanisms, individually or combined, can be sufficient to generate radial patterns. In the first, new material is added locally at the position of the root hair. In the second, increased tension in the initiation area provides a mechanism. Finally, we describe how a molecular model of Rho-of-plant (ROP) GTPases activation driven by auxin can position a patch of activated ROP protein basally along a 2D root epidermal cell plasma membrane, paving the way for models where mechanical and molecular mechanisms cooperate in the initial placement and outgrowth of root hairs.

14.
Plant Physiol ; 172(4): 2245-2260, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27803190

RESUMO

The outermost cell layer of plants, the epidermis, and its outer (lateral) membrane domain facing the environment are continuously challenged by biotic and abiotic stresses. Therefore, the epidermis and the outer membrane domain provide important selective and protective barriers. However, only a small number of specifically outer membrane-localized proteins are known. Similarly, molecular mechanisms underlying the trafficking and the polar placement of outer membrane domain proteins require further exploration. Here, we demonstrate that ACTIN7 (ACT7) mediates trafficking of the PENETRATION3 (PEN3) outer membrane protein from the trans-Golgi network (TGN) to the plasma membrane in the root epidermis of Arabidopsis (Arabidopsis thaliana) and that actin function contributes to PEN3 endocytic recycling. In contrast to such generic ACT7-dependent trafficking from the TGN, the EXOCYST84b (EXO84b) tethering factor mediates PEN3 outer-membrane polarity. Moreover, precise EXO84b placement at the outer membrane domain itself requires ACT7 function. Hence, our results uncover spatially and mechanistically distinct requirements for ACT7 function during outer lateral membrane cargo trafficking and polarity establishment. They further identify an exocyst tethering complex mediator of outer lateral membrane cargo polarity.


Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Arabidopsis/metabolismo , Membrana Celular/metabolismo , Actinas/metabolismo , Proteínas de Arabidopsis/metabolismo , Biomarcadores/metabolismo , Membrana Celular/ultraestrutura , Citoplasma/metabolismo , Endocitose , Mutação/genética , Transporte Proteico , Via Secretória , Rede trans-Golgi/metabolismo , Rede trans-Golgi/ultraestrutura
15.
Arch Gynecol Obstet ; 294(1): 115-21, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26781262

RESUMO

PURPOSE: Pelvic organ prolapse (POP) impairs quality of life (QoL) due to vaginal bulge symptoms and changes in bladder/bowel and sexual function. The effect of alloplastic meshes on QoL is still being discussed. The purpose of this study was to prospectively evaluate the effect of mesh implantation on QoL and sexual function over 1 year. METHODS: 289 women with cystocele > stage I were included in this prospective multicenter study, with nine hospitals participating (ClinicalTrials.gov NCT01084889). Mesh exposures rates and pelvic floor-related QoL using the validated German version of the p-QoL questionnaire were evaluated as the primary endpoints. Based on a single-sided binominal test with α = 0.05 and a power of 0.80, a sample size of 225 for the mesh exposures was calculated. The mesh used was a 6-arm mesh with titanium coating (TILOOP(®) Total 6, sponsor pfm medical ag, Germany). Preoperative data were compared to 6 and 12 months postoperative data, using Wilcoxon test. RESULTS: The mean age of the patients was 67 years (min 43, max 87). All domains of QoL improved significantly compared after surgery: mean prolapse score dropped from 73.7 to 19.4 after 6 and 16.2 after 12 months (p < 0.001). Sexual function also improved significantly. The rate of dyspareunia was lower at follow-up. CONCLUSIONS: In this prospective trial, a significant positive effect of mesh implantation on pelvic floor-related QoL was observed. These findings remained stable 1 year after surgery with further improvement. This trial adds further data to the ongoing discussion on the role and risk of meshes in POP surgery.


Assuntos
Cistocele/cirurgia , Prolapso de Órgão Pélvico/diagnóstico , Prolapso de Órgão Pélvico/cirurgia , Qualidade de Vida , Comportamento Sexual , Telas Cirúrgicas/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Dispareunia/etiologia , Feminino , Seguimentos , Alemanha , Humanos , Pessoa de Meia-Idade , Satisfação do Paciente , Diafragma da Pelve/fisiopatologia , Prolapso de Órgão Pélvico/complicações , Prolapso de Órgão Pélvico/psicologia , Complicações Pós-Operatórias , Período Pós-Operatório , Estudos Prospectivos , Inquéritos e Questionários , Resultado do Tratamento , Vagina/cirurgia
16.
Methods Mol Biol ; 1370: 227-39, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26659966

RESUMO

Eukaryotic cells contain membranes exhibiting different levels of lipid order mostly related to their relative amount of sterol-rich domains, thought to mediate temporal and spatial organization of cellular processes. We previously provided evidence in Arabidopsis thaliana that sterols are crucial for execution of cytokinesis, the last stage of cell division. Recently, we used di-4-ANEPPDHQ, a fluorescent probe sensitive to order of lipid phases, to quantify the level of membrane order of the cell plate, the membrane structure separating daughter cells during somatic cytokinesis of higher plant cells. By employing quantitative, ratiometric fluorescence microscopy for mapping localized lipid order levels, we revealed that the Arabidopsis cell plate represents a high-lipid-order domain of the plasma membrane. Here, we describe step-by-step protocols and troubleshooting for ratiometric live imaging procedures employing the di-4-ANEPPDHQ fluorescent probe for quantification of membrane lipid order during plant cell division in suspension cell cultures and roots of Arabidopsis thaliana.


Assuntos
Arabidopsis/citologia , Corantes Fluorescentes/análise , Lipídeos de Membrana/análise , Microscopia de Fluorescência/métodos , Mitose , Compostos de Piridínio/análise , Arabidopsis/ultraestrutura , Técnicas de Cultura de Células , Microdomínios da Membrana/ultraestrutura , Imagem Óptica/métodos , Raízes de Plantas/citologia , Raízes de Plantas/ultraestrutura
17.
Wien Med Wochenschr ; 165(7-8): 164-77, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25930015

RESUMO

Vulvar malignancies are important tumors of the female reproductive system. They represent a serious health issue with an incidence between 2 and 7 per 100,000 and year. We provide a review about most important cancer entities, i.e., melanoma, squamous cell carcinoma, basal cell carcinoma, neuroendocrine cancer, and skin adnexal malignancies.Squamous cell carcinoma is the most common vulvar malignancy that can develop from vulvar intraepithelial neoplasia or de novo. Basal cell carcinoma represents only 2% of all vulvar cancers. Melanoma of the vulva exists in two major types-superficial spreading and acral lentiginous. A special feature is the occurrence of multiple vulvar melanomas. Of the adnexal cancer types Paget's disease and carcinoma are seen more frequently than other adnexal malignancies. The dermatologist should be aware of this problem, since he might be the first to be consulted by patients for vulvar disease. Treatment should be interdisciplinary in close association to gynecologists, oncologists, and radiologists.


Assuntos
Neoplasias Cutâneas/patologia , Neoplasias Vulvares/patologia , Carcinoma in Situ/patologia , Carcinoma Basocelular/patologia , Carcinoma de Células Escamosas/patologia , Diagnóstico Diferencial , Feminino , Humanos , Melanoma/patologia , Estadiamento de Neoplasias , Neoplasias de Anexos e de Apêndices Cutâneos/patologia , Tumores Neuroendócrinos/patologia , Doença de Paget Extramamária/patologia , Prognóstico , Pele/patologia , Vulva/patologia
19.
Nat Plants ; 1: 15162, 2015 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-27251533

RESUMO

Development of diverse multicellular organisms relies on coordination of single-cell polarities within the plane of the tissue layer (planar polarity). Cell polarity often involves plasma membrane heterogeneity generated by accumulation of specific lipids and proteins into membrane subdomains. Coordinated hair positioning along Arabidopsis root epidermal cells provides a planar polarity model in plants, but knowledge about the functions of proteo-lipid domains in planar polarity signalling remains limited. Here we show that Rho-of-plant (ROP) 2 and 6, phosphatidylinositol-4-phosphate 5-kinase 3 (PIP5K3), DYNAMIN-RELATED PROTEIN (DRP) 1A and DRP2B accumulate in a sterol-enriched, polar membrane domain during root hair initiation. DRP1A, DRP2B, PIP5K3 and sterols are required for planar polarity and the AGCVIII kinase D6 PROTEIN KINASE (D6PK) is a modulator of this process. D6PK undergoes phosphatidylinositol-4,5-bisphosphate- and sterol-dependent basal-to-planar polarity switching into the polar, lipid-enriched domain just before hair formation, unravelling lipid-dependent D6PK localization during late planar polarity signalling.

20.
Physiol Plant ; 153(3): 440-53, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25124848

RESUMO

Patterned differentiation of distinct cell types is essential for the development of multicellular organisms. The root epidermis of Arabidopsis thaliana is composed of alternating files of root hair and non-hair cells and represents a model system for studying the control of cell-fate acquisition. Epidermal cell fate is regulated by a network of genes that translate positional information from the underlying cortical cell layer into a specific pattern of differentiated cells. While much is known about the genes of this network, new players continue to be discovered. Here we show that the SABRE (SAB) gene, known to mediate microtubule organization, anisotropic cell growth and planar polarity, has an effect on root epidermal hair cell patterning. Loss of SAB function results in ectopic root hair formation and destabilizes the expression of cell fate and differentiation markers in the root epidermis, including expression of the WEREWOLF (WER) and GLABRA2 (GL2) genes. Double mutant analysis reveal that wer and caprice (cpc) mutants, defective in core components of the epidermal patterning pathway, genetically interact with sab. This suggests that SAB may act on epidermal patterning upstream of WER and CPC. Hence, we provide evidence for a role of SAB in root epidermal patterning by affecting cell-fate stabilization. Our work opens the door for future studies addressing SAB-dependent functions of the cytoskeleton during root epidermal patterning.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica de Plantas , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas Proto-Oncogênicas c-myb/metabolismo , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Diferenciação Celular , Proteínas de Ligação a DNA/genética , Redes Reguladoras de Genes , Genes Reporter , Genótipo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Modelos Biológicos , Mutação , Epiderme Vegetal/genética , Epiderme Vegetal/crescimento & desenvolvimento , Epiderme Vegetal/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Mapeamento de Interação de Proteínas , Proteínas Proto-Oncogênicas c-myb/genética , Plântula/genética , Plântula/crescimento & desenvolvimento , Plântula/metabolismo
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