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Cytokinesis in land plants involves the formation of a cell plate that develops into the new cell wall. Callose, a ß-1,3 glucan, accumulates at later stages of cell plate development, presumably to stabilize this delicate membrane network during expansion. Cytokinetic callose is considered specific to multicellular plant species, because it has not been detected in unicellular algae. Here we present callose at the cytokinesis junction of the unicellular charophyte, Penium margaritaceum Callose deposition at the division plane of P. margaritaceum showed distinct, spatiotemporal patterns likely representing distinct roles of this polymer in cytokinesis. Pharmacological inhibition of callose deposition by endosidin 7 resulted in cytokinesis defects, consistent with the essential role for this polymer in P. margaritaceum cell division. Cell wall deposition at the isthmus zone was also affected by the absence of callose, demonstrating the dynamic nature of new wall assembly in P. margaritaceum The identification of candidate callose synthase genes provides molecular evidence for callose biosynthesis in P. margaritaceum The evolutionary implications of cytokinetic callose in this unicellular zygnematopycean alga is discussed in the context of the conquest of land by plants.This article has an associated First Person interview with the first author of the paper.
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Carofíceas , Citocinese , Parede Celular , GlucanosRESUMO
The plant endomembrane system facilitates the transport of polysaccharides, associated enzymes, and glycoproteins through its dynamic pathways. Although enzymes involved in cell wall biosynthesis have been identified, little is known about the endomembrane-based transport of glycan components. This is partially attributed to technical challenges in biochemically determining polysaccharide cargo in specific vesicles. Here, we introduce a hybrid approach addressing this limitation. By combining vesicle isolation with a large-scale carbohydrate antibody arraying technique, we charted an initial large-scale map describing the glycome profile of the SYNTAXIN OF PLANTS61 (SYP61) trans-Golgi network compartment in Arabidopsis (Arabidopsis thaliana). A library of antibodies recognizing specific noncellulosic carbohydrate epitopes allowed us to identify a range of diverse glycans, including pectins, xyloglucans (XyGs), and arabinogalactan proteins in isolated vesicles. Changes in XyG- and pectin-specific epitopes in the cell wall of an Arabidopsis SYP61 mutant corroborate our findings. Our data provide evidence that SYP61 vesicles are involved in the transport and deposition of structural polysaccharides and glycoproteins. Adaptation of our methodology can enable studies characterizing the glycome profiles of various vesicle populations in plant and animal systems and their respective roles in glycan transport defined by subcellular markers, developmental stages, or environmental stimuli.
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Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Glicômica , Glicoproteínas/metabolismo , Polissacarídeos/metabolismo , Proteínas Qa-SNARE/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Transporte Biológico , Carboidratos/imunologia , Parede Celular/metabolismo , Epitopos/imunologia , Mutação , Transporte Proteico , Proteínas Qa-SNARE/genética , Rede trans-Golgi/metabolismoRESUMO
BACKGROUND: The forgotten joint score (FJS) is a recent scoring system that assesses how natural the prosthesis feels after total joint arthroplasty. Although the FJS has been extensively applied in populations with total hip prosthetics, less is known about the patients undergoing total knee arthroplasty (TKA). The purpose of this study is to investigate the temporal relationship between TKA and the FJS. METHODS: We evaluated 566 patients after TKA using the FJS questionnaire. Scores were calculated at the follow-up intervals of 1 (n = 79), 6 (n = 78), 12 (n = 81), 24 (n = 100), 36 (n = 76), 48 (n = 75), and 60 (n = 77) months. The scores ranged from 0-100, with a higher score indicating a more natural or "forgotten" joint. RESULTS: Postoperative FJS averages were 39.3 ± 27.4 at 1 month, 59.4 ± 28.3 at 6 months, 72.5 ± 24.2 at 1 year, 76.4 ± 23.4 at 2 years, 75.1 ± 24.2 at 3 years, 68.6 ± 28.7 at 4 years, and 64.4 ± 29.0 at 5 years. The average score at 1 month was significantly lower than the average scores at all other intervals. The average score at 6 months was significantly lower than the average scores at 12, 24, and 36 months. The average score at 60 months was significantly lower than the average score at 24 months. CONCLUSION: Based on the findings of this study, patients can expect marked improvement in the natural feel of the prosthesis during the first year after TKA, slight continued improvement at 2 and 3 years, and a decline after 4 years.
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Artroplastia do Joelho , Articulação do Joelho/cirurgia , Joelho/cirurgia , Recuperação de Função Fisiológica , Idoso , Índice de Massa Corporal , Estudos Transversais , Feminino , Seguimentos , Humanos , Joelho/fisiologia , Articulação do Joelho/fisiologia , Masculino , Pessoa de Meia-Idade , Ortopedia , Período Pós-Operatório , Índice de Gravidade de Doença , Inquéritos e Questionários , Resultado do TratamentoRESUMO
Expressed human milk can be donated or sold through a variety of channels, including human milk banks, corporations or individuals, or peer-to-peer milk sharing. There is a paucity of research regarding the nutrient and bioactive profiles of expressed human milk exchanged through commerce-free scenarios, including peer-to-peer milk sharing. The study objective was to evaluate the macronutrient, antimicrobial protein, and bacteria composition in expressed human milk acquired via commerce-free arrangements. Expressed human milk samples were collected from the following commerce-free scenarios: milk expressed for a mother's or parent's own infant (MOM; N = 30); unpasteurized milk donated to a non-profit milk bank (BANKED; N = 30); milk expressed for peer-to-peer milk sharing (SHARED; N = 31); and health professional-facilitated milk sharing where donors are serologically screened and milk is dispensed raw (SCREENED; N = 30). Analyses were conducted for total protein, lactose, percent fat and water, lysozyme activity, immunoglobulin A (IgA) activity, total aerobic bacteria, coliform, and Staphylococcus aureus. No bacterial growth was observed in 52/121 samples, and 15/121 had growth greater than 5.0 log colony-forming units/mL. There was no evidence of differences by groups (p > .05) in lactose, fat, water, lysozyme activity, sIgA activity, aerobic bacteria, coliforms, and S. aureus. Mean protein values (95% confidence interval) were 1.5 g/dL (1.4, 1.6) for BANKED, 1.4 g/dL (1.3, 1.5) for MOM, 1.6 g/dL (1.5, 1.7) for SCREENED, and 1.5 g/dL (1.4, 1.6) for SHARED, which was not significantly different (p = .081). This research contributes to growing literature on the risks and benefits of uncompensated, peer-to-peer milk sharing.
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Anti-Infecciosos/análise , Proteínas do Leite/análise , Leite Humano/química , Leite Humano/microbiologia , Nutrientes/análise , Bactérias Aeróbias/isolamento & purificação , Extração de Leite , Enterobacteriaceae/isolamento & purificação , Gorduras/análise , Feminino , Humanos , Imunoglobulina A/análise , Lactose/análise , Bancos de Leite Humano , Muramidase/análise , Projetos Piloto , Staphylococcus aureus/isolamento & purificação , Doadores de TecidosRESUMO
Although cytokinesis is vital for plant growth and development, our mechanistic understanding of the highly regulated membrane and cargo transport mechanisms in relation to polysaccharide deposition during this process is limited. Here, we present an in-depth characterization of the small molecule endosidin 7 (ES7) inhibiting callose synthase activity and arresting late cytokinesis both in vitro and in vivo in Arabidopsis (Arabidopsis thaliana). ES7 is a specific inhibitor for plant callose deposition during cytokinesis that does not affect endomembrane trafficking during interphase or cytoskeletal organization. The specificity of ES7 was demonstrated (1) by comparing its action with that of known inhibitors such as caffeine, flufenacet, and concanamycin A and (2) across kingdoms with a comparison in yeast. The interplay between cell plate-specific post-Golgi vesicle traffic and callose accumulation was analyzed using ES7, and it revealed unique and temporal contributions of secretory and endosomal vesicles in cell plate maturation. While RABA2A-labeled vesicles, which accumulate at the early stage of cell plate formation, were not affected by ES7, KNOLLE was differentially altered by the small molecule. In addition, the presence of clathrin-coated vesicles in cells containing elevated levels of callose and their reduction under ES7 treatment further support the role of endocytic membrane remodeling in the maturing cell plate while the plate is stabilized by callose. Taken together, these data show the essential role of callose during the late stages of cell plate maturation and establish the temporal relationship between vesicles and regulatory proteins at the cell plate assembly matrix during polysaccharide deposition.
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BACKGROUND: The association between student characteristics and depression among students attending women's colleges (single-sex institutions of higher education that exclude or limit males from admission) is poorly understood. Our objective was to estimate the prevalence of depression and determine behavioral and social characteristics associated with depression among students attending a women's college. METHODS: We administered a cross-sectional Internet-based survey between April and May 2012 to students (n = 277) enrolled at a private women's college in the southeastern US. Center for Epidemiologic Studies Depression (CES-D) and Depression Anxiety Stress Scale 21 (DASS-21) instruments measured self-reported depression. Bivariate and multivariable logistic regression methods were used to estimate adjusted associations. RESULTS: Prevalence of depression measured by CES-D and DASS-21 instruments was 26.3% (95% confidence interval [CI] 20.8-32.3%) and 26.0% (95% CI 20.4-32.3%), respectively. After adjusting for confounders, absence of strong social support (prevalence odds ratio [OR] = 4.3, 95% CI 1.4-13.7), history of mental health disorder (OR = 4.8 95% CI 1.9-12.4), and poor sleep hygiene (OR = 2.8, 95% CI 1.3-5.8) were associated with depression. CONCLUSIONS: This cross-sectional survey identified absence of strong social support, history of mental health disorder, and poor sleep hygiene as potential predictors of depression among students attending a women's college. Further investigation of these factors may inform depression interventions for students attending women's colleges and other undergraduate student populations.
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Depressão/epidemiologia , Transtorno Depressivo/epidemiologia , Transtornos do Sono-Vigília/epidemiologia , Estudantes/estatística & dados numéricos , Universidades , Mulheres/psicologia , Adolescente , Adulto , Estudos Transversais , Depressão/psicologia , Transtorno Depressivo/psicologia , Feminino , Humanos , Modelos Logísticos , Transtornos Mentais/epidemiologia , Análise Multivariada , Razão de Chances , Fatores de Risco , Transtornos do Sono-Vigília/psicologia , Apoio Social , Estudantes/psicologia , Inquéritos e Questionários , Adulto JovemRESUMO
Background: When comparing functional outcomes of patients with unicompartmental knee arthroplasty (UKA) versus total knee arthroplasty (TKA), studies often report the UKA as the preferred procedure; however, recent improvements in the design of modern TKA implants have aimed at narrowing this gap. Purpose: We sought to compare the "feel" of modern TKA implants to that of UKA, using the Forgotten Joint Score (FJS), a validated patient-reported outcome measure. Methods: We performed a retrospective review of patients who underwent TKA and UKA at 2 institutions between 2014 and 2017. All UKA procedures were robotic arm-assisted with a single implant, "traditional TKAs" were performed using traditional posterior-stabilized implants, and "modern TKAs" were performed using posterior-stabilized implants with a modern design. Differences in FJS were assessed using 1-way analysis of variance and independent 2-sample t tests. Results: A total of 600 patients were included in our study, with 200 patients in each surgical subcategory. Mean age was 62.8 ± 10.2 years and mean body mass index was 29.9 ± 4.9. Modern TKA and UKA had similar FJS at 1 year. While modern TKA had a significantly higher FJS than traditional TKA, UKA did not have a significantly higher FJS than traditional TKA. Conclusion: Our retrospective analysis found no significant differences in the FJS of patients who underwent UKA and TKA with a modern design; however, both had superior scores than traditional TKA designs. This finding suggests that modern TKA designs may have the potential to achieve the natural feeling that is typically associated with joint-conserving surgeries such as UKA, although longer follow-up is necessary.
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The Centers for Disease Control and Prevention (CDC)'s Division of Reproductive Health and Harvard T.H. Chan School of Public Health (HSPH) Program Evaluation Practicum (CDC/HSPH Practicum) is a mutually beneficial workforce development partnership formed to provide state, local, and tribal public health organizations with an evaluation plan for a maternal and child health (MCH) program. State, local, and tribal public health organizations submit an MCH program in need of evaluation for inclusion consideration. Student pairs are matched with the selected programs in a 3-week practical field-based experience. This Practicum provides didactic training for both program staff and students followed by field work at the public health organizations. Students provide organizations with comprehensive evaluation plans, complete with logic model, methodology, and indicators. Since the Practicum's inception in 2013, 104 HSPH graduate students have been trained and 30 states and 1 territory have participated and received evaluation plans for their MCH programs. The utility and importance of the CDC/HSPH Practicum is evidenced by program staff and student feedback. Multiple states have implemented the plans designed by the students, with some evaluations leading to program enhancements. The CDC/HSPH Practicum prepares students for the workforce and adds much needed capacity to public health organizations by providing them with evaluation knowledge and skills, and usable evaluation plans to improve MCH-a win-win for all.
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Saúde Pública , Estudantes , Criança , Humanos , Avaliação de Programas e Projetos de Saúde , Recursos Humanos , Desenvolvimento de PessoalRESUMO
Cytokinesis in plants is fundamentally different from that in animals and fungi. In plant cells, a cell plate forms through the fusion of cytokinetic vesicles and then develops into the new cell wall, partitioning the cytoplasm of the dividing cell. The formation of the cell plate entails multiple stages that involve highly orchestrated vesicle accumulation, fusion and membrane maturation, which occur concurrently with the timely deposition of polysaccharides such as callose, cellulose and cross-linking glycans. This review summarizes the major stages in cytokinesis, endomembrane components involved in cell plate assembly and its transition to a new cell wall. An animation that can be widely used for educational purposes further summarizes the process.
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Parede Celular , Citocinese , Parede Celular/metabolismo , Citoplasma/metabolismo , Células Vegetais/metabolismo , Plantas/genética , Plantas/metabolismo , Polissacarídeos/metabolismoRESUMO
The intensive use of groundwater in agriculture under the current climate conditions leads to acceleration of soil salinization. Given that almond is a salt-sensitive crop, selection of salt-tolerant rootstocks can help maintain productivity under salinity stress. Selection for tolerant rootstocks at an early growth stage can reduce the investment of time and resources. However, salinity-sensitive markers and salinity tolerance mechanisms of almond species to assist this selection process are largely unknown. We established a microscopy-based approach to investigate mechanisms of stress tolerance in and identified cellular, root anatomical, and molecular traits associated with rootstocks exhibiting salt tolerance. We characterized three almond rootstocks: Empyrean-1 (E1), Controller-5 (C5), and Krymsk-86 (K86). Based on cellular and molecular evidence, our results show that E1 has a higher capacity for salt exclusion by a combination of upregulating ion transporter expression and enhanced deposition of suberin and lignin in the root apoplastic barriers, exodermis, and endodermis, in response to salt stress. Expression analyses revealed differential regulation of cation transporters, stress signaling, and biopolymer synthesis genes in the different rootstocks. This foundational study reveals the mechanisms of salinity tolerance in almond rootstocks from cellular and structural perspectives across a root developmental gradient and provides insights for future screens targeting stress response.
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Pattern recognition receptors (PRRs) such as Toll-like receptors (TLRs) and NOD-like receptors (NLRs) play crucial roles in the underlying mechanisms of metabolic syndrome (MetS). Mainly, these receptors have been suggested to participate in the pathophysiological processes involved in the complications associated with this condition. Therefore, to evolve therapeutic strategies targeting PRRs might be an imperative approach to avoid the development of further complications in human subjects. In this work, we discuss the understanding regarding the roles of PRRs in the pathways of MetS to further describe potential advancements made to target these receptors within this pathology.
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Síndrome Metabólica/fisiopatologia , Síndrome Metabólica/terapia , Receptores de Reconhecimento de Padrão/metabolismo , Animais , Humanos , Transdução de SinaisRESUMO
Cytokinesis in plants requires the activity of RAB GTPases to regulate vesicle-mediated contribution of material to the developing cell plate. While some plant RAB GTPases have been shown to be involved in cell plate formation, many still await functional assignment. Here, we report cell plate localization for YFP-RABA1e in Arabidopsis thaliana and use the cytokinesis inhibitor Endosidin 7 to provide a detailed description of its localization compared to YFP-RABA2a. Differences between YFP-RABA2a and YFP-RABA1e were observed in late-stage cell plates under DMSO control treatment, and became more apparent under Endosidin 7 treatment. Taken together, our results suggest that individual RAB GTPases might make different contributions to cell plate formation and further demonstrates the utility of ES7 probe to dissect them.
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Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/fisiologia , Arabidopsis/metabolismo , Citocinese/fisiologia , Quinolonas/farmacologia , Proteínas rab de Ligação ao GTP/fisiologia , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Arabidopsis/ultraestrutura , Proteínas de Arabidopsis/análise , Parede Celular/efeitos dos fármacos , Parede Celular/metabolismo , Parede Celular/ultraestrutura , Citocinese/efeitos dos fármacos , Transdução de Sinais , Proteínas rab de Ligação ao GTP/análise , Proteínas rab de Ligação ao GTP/metabolismoRESUMO
Unconventional protein secretion (UPS) describes secretion pathways that bypass one or several of the canonical secretion pit-stops on the way to the plasma membrane, and/or involve the secretion of leaderless proteins. So far, alternatives to conventional secretion were primarily observed and studied in yeast and animal cells. The sessile lifestyle of plants brings with it unique restraints on how they adapt to adverse conditions and environmental challenges. Recently, attention towards unconventional secretion pathways in plant cells has substantially increased, with the large number of leaderless proteins identified through proteomic studies. While UPS pathways in plants are certainly not yet exhaustively researched, an emerging notion is that induction of UPS pathways is correlated with pathogenesis and stress responses. Given the multitude UPS events observed, comprehensively organizing the routes proteins take to the apoplast in defined UPS categories is challenging. With the establishment of a larger collection of studied plant proteins taking these UPS pathways, a clearer picture of endomembrane trafficking as a whole will emerge. There are several novel enabling technologies, such as vesicle proteomics and chemical genomics, with great potential for dissecting secretion pathways, providing information about the cargo that travels along them and the conditions that induce them.