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1.
Ann Gen Psychiatry ; 22(1): 52, 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-38087387

RESUMEN

BACKGROUND: Bipolar disorder is a mental illness characterized by recurring episodes of mania and depression and is known to cause social impairment. Additionally, it has been revealed that bipolar disorder increases the risk of divorce and loss of family member support, which can worsen the prognosis. However, there is limited evidence regarding the predictive factors of divorce among patients with bipolar disorder in real-world settings. METHODS: This study utilized an observational approach and involved psychiatrists from 176 member clinics of the Japanese Association of Neuro-Psychiatric Clinics. They were requested to conduct a retrospective review of medical records and complete a questionnaire focused on patients diagnosed with bipolar disorder. The data collection period for baseline patient characteristics spanned from September to October 2017. Next, we investigated the incidence of divorce over a 2-year period, ranging from baseline to September to October 2019. RESULTS: A total of 1071 outpatients with bipolar disorder were included in the analysis, and 2.8% (30/1071) experienced divorce during the first 2 years of observation. The incidence of divorce in this population was considerably higher than that in the general Japanese population. Binomial logistic regression analysis confirmed that a younger baseline age and lower BMI values were statistically significant predictors of divorce occurrence for all study participants. The predictors of divorce were then examined separately by sex. The results revealed that for men, a younger age at baseline and having bipolar I disorder compared to bipolar II disorder were statistically significant predictors of divorce. In contrast, for women, having a lower BMI and using anxiolytics emerged as statistically significant predictors of divorce. CONCLUSIONS: In this study, a younger baseline age and lower BMI values were statistically significant predictors of divorce in patients with bipolar disorder. Notably, the predictors of divorce varied significantly between men and women. These findings provide important insights from a family perspective regarding social support for individuals with bipolar disorder in real-world clinical settings.

2.
J Glob Antimicrob Resist ; 35: 325-331, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37918785

RESUMEN

OBJECTIVES: The production of expanded-spectrum beta-lactamases (ESBLs) and fluoroquinolone resistance in Enterobacteriaceae has become a global concern. The aim of this study was to investigate the spread of ESBL-producing and fluoroquinolone-resistant avian pathogenic Escherichia coli (APEC) in Kagoshima, a prefecture with the largest amount of poultry in Japan. METHODS: The antimicrobial susceptibility and genetic characteristics of 228 APEC strains isolated from 57 farms in Kagoshima Prefecture, Japan, between 2005 and 2017 were analysed. Information about the companies with hatcheries connected to the farms was also collected, and the epidemiologic relatedness of APEC strains and the processes of adopting chicks were compared. RESULTS: Seven CTX-M-type ESBL genes, blaCTX-M-1, blaCTX-M-2, blaCTX-M-14, blaCTX-M-15, blaCTX-M-25, blaCTX-M-55, and blaCTX-M-65, were found in 60 (26.3%) of the 228 APEC strains. The ciprofloxacin-resistant strains belonged to 10 different sequence types (ST10, ST23, ST93, ST155, ST156, ST350, ST359, ST602, ST648, and ST9479), and the two ST602 strains showed remarkably high ciprofloxacin resistance (MIC: 128 µg/mL) and had amino acid mutations in GyrA (S83L and D87N), ParC (S80I), and ParE (E460A). A CTX-M-55-type ESBL-producing fluoroquinolone-resistant Og78-ST23 strain was isolated multiple times over two years on a farm. Furthermore, epidemiologically closely related strains were isolated from different farms that used the same common hatcheries. CONCLUSIONS: APEC is often transferred from hatcheries to farms via healthy chicks, and the prudent use of antimicrobials and careful monitoring of resistant strains on poultry farms and hatcheries are important in preventing the selection and spread of high-risk APEC strains such as CTX-M-55-type ESBL-producing Og78-ST23.


Asunto(s)
Infecciones por Escherichia coli , Fluoroquinolonas , Animales , Humanos , Fluoroquinolonas/farmacología , Japón/epidemiología , Antibacterianos/uso terapéutico , Escherichia coli , Infecciones por Escherichia coli/epidemiología , Infecciones por Escherichia coli/veterinaria , Infecciones por Escherichia coli/tratamiento farmacológico , Pollos , Aves de Corral , Ciprofloxacina
3.
Front Psychiatry ; 14: 1078045, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37009121

RESUMEN

Background: Bipolar disorder is a psychiatric disorder that causes recurrent manic and depressive episodes, leading to decreased levels of social functioning and suicide. Patients who require hospitalization due to exacerbation of bipolar disorder have been reported to subsequently have poor psychosocial functioning, and so there is a need to prevent hospitalization. On the other hand, there is a lack of evidence regarding predictors of hospitalization in real-world clinical practice. Methods: The multicenter treatment survey on bipolar disorder (MUSUBI) in Japanese psychiatric clinics was an observational study conducted to provide evidence regarding bipolar disorder in real-world clinical practice. Psychiatrists were asked, as part of a retrospective medical record survey, to fill out a questionnaire about patients with bipolar disorder who visited 176 member clinics of the Japanese Association of Neuro-Psychiatric Clinics. Our study extracted baseline patient characteristics from records dated between September and October 2016, including comorbidities, mental status, duration of treatment, Global Assessment of Functioning (GAF) score, and pharmacological treatment details. The incidence and predictors of hospitalization among patients with bipolar disorder over a 1-year period extending from that baseline to September-October 2017 were examined. Results: In total, 2,389 participants were included in our study, 3.06% of whom experienced psychiatric hospitalization over the course of 1 year from baseline. Binomial logistic regression analysis revealed that the presence of psychiatric hospitalization was correlated with bipolar I disorder, lower baseline GAF scores, unemployment, substance abuse and manic state. Conclusions: Our study revealed that 3.06% of outpatients with bipolar disorder were subjected to psychiatric hospitalization during a 1-year period that extended to September-October 2017. Our study suggested that bipolar I disorder, lower baseline GAF scores, unemployment, substance abuse and baseline mood state could be predictors of psychiatric hospitalization. These results may be useful for clinicians seeking to prevent psychiatric hospitalization for bipolar disorder.

4.
J Psychiatr Res ; 151: 683-692, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35675718

RESUMEN

BACKGROUND: There is limited evidence regarding predictors of long-term clinical outcomes in patients with bipolar disorder (BD). The objective of this study was to describe 3-year clinical outcomes and identify their predictors from participants in the multicenter treatment survey for BD in psychiatric outpatient clinics (MUSUBI). METHODS: The MUSUBI was a naturalistic study investigating patients with BD in real-world clinical practice. Our study extracted data regarding 1647 outpatients with BD from 2016, 2017, and 2019 as baseline, 1-year, and 3-year assessments. As clinical outcomes, we assessed the presence of time ill (depressive and manic) during the 1 year prior to the 3-year assessment and durable remission (53 weeks or more) prior to the 3-year assessment. RESULTS: Participants with durable remission prior to the 3-year assessment had significant associations with diagnosis of a personality disorder and duration of continuous remission at baseline. Regarding the presence of depressive symptoms during the 1 year prior to the 3-year assessment, work status, Global Assessment of Functioning (GAF) scores, suicidal ideation, and duration of continuous remission at baseline had significant associations with this outcome. CONCLUSIONS: At the 3-year assessment, 19.3% of participants (318/1647) achieved durable remission, while 47.5% of them (782/1647) were not remitted. Our findings can help clinicians predict the illness course of BD by understanding demographic and clinical characteristics.


Asunto(s)
Trastorno Bipolar , Instituciones de Atención Ambulatoria , Trastorno Bipolar/diagnóstico , Trastorno Bipolar/epidemiología , Trastorno Bipolar/terapia , Humanos , Pacientes Ambulatorios , Trastornos de la Personalidad/complicaciones , Ideación Suicida
5.
Plants (Basel) ; 11(9)2022 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-35567202

RESUMEN

The 2021 summer heat waves experienced in the Pacific Northwest led to considerable fruit damage in many apple production zones. Sunburn browning (SB) was a particularly evident symptom. To understand the mechanism underlying the damage and to facilitate the early assessment of compromised fruit quality, we conducted a study on external characteristics and internal quality attributes of SB 'Ambrosia' apple (Malus domestica var. Ambrosia) and evaluated the fruit loss on five rootstocks. The cell integrity of the epidermal and hypodermal layers of fruit skins in the SB patch was compromised. Specifically, the number of chloroplasts and anthocyanin decreased in damaged cells, while autofluorescent stress-related compounds accumulated in dead cells. Consequently, the affected sun-exposed skin demonstrated a significant increase in differential absorbance between 670 nm and 720 nm, measured using a handheld apple DA meter, highlighting the potential of using this method as a non-destructive early indicator for sunburn damage. Sunburn browning eventually led to lower fruit weight, an increase in average dry matter content, soluble solids content, acidity, deteriorated weight retention, quicker loss of firmness, and accelerated ethylene emission during ripening. Significant inconsistency was found between the sun-exposed and shaded sides in SB apples regarding dry matter content, firmness, and tissue water potential, which implied preharvest water deficit in damaged tissues and the risk of quicker decline of postharvest quality. Geneva 935 (G.935), a large-dwarfing rootstock with more vigor and higher water transport capacity, led to a lower ratio of heat-damaged fruits and a higher yield of disorder-free fruits, suggesting rootstock selection as a long-term horticultural measure to mitigate summer heat stress.

6.
Open Biol ; 12(5): 210208, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35506204

RESUMEN

All plant cells are encased in primary cell walls that determine plant morphology, but also protect the cells against the environment. Certain cells also produce a secondary wall that supports mechanically demanding processes, such as maintaining plant body stature and water transport inside plants. Both these walls are primarily composed of polysaccharides that are arranged in certain patterns to support cell functions. A key requisite for patterned cell walls is the arrangement of cortical microtubules that may direct the delivery of wall polymers and/or cell wall producing enzymes to certain plasma membrane locations. Microtubules also steer the synthesis of cellulose-the load-bearing structure in cell walls-at the plasma membrane. The organization and behaviour of the microtubule array are thus of fundamental importance to cell wall patterns. These aspects are controlled by the coordinated effort of small GTPases that probably coordinate a Turing's reaction-diffusion mechanism to drive microtubule patterns. Here, we give an overview on how wall patterns form in the water-transporting xylem vessels of plants. We discuss systems that have been used to dissect mechanisms that underpin the xylem wall patterns, emphasizing the VND6 and VND7 inducible systems, and outline challenges that lay ahead in this field.


Asunto(s)
Pared Celular , Xilema , Membrana Celular/metabolismo , Pared Celular/metabolismo , Microtúbulos/metabolismo , Plantas/metabolismo , Agua/metabolismo , Xilema/metabolismo
7.
PLoS One ; 16(12): e0262129, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34972188

RESUMEN

BACKGROUND: Bipolar disorder is a mental illness in which manic and depressive states are repeated, causing psychosocial dysfunction. Manic/hypomanic episodes cause problems with interpersonal, social and financial activities, but there is limited evidence regarding the predictors of manic/hypomanic episodes in real-world clinical practice. METHODS: The multicenter treatment survey on bipolar disorder (MUSUBI) in Japanese psychiatric clinics was administered in an observational study that was conducted to accumulate evidence regarding bipolar disorder in real-world clinical practice. Psychiatrists were asked to complete a questionnaire about patients with bipolar disorder who visited 176 member clinics of the Japanese Association of Neuro-Psychiatric Clinics by conducting a retrospective medical record survey. Our study extracted baseline patient characteristics from September to October 2016, including comorbidities, mental status, duration of treatment, Global Assessment of Functioning (GAF) score, and pharmacological treatment details. We investigated the presence or absence of manic/hypomanic episodes over the course of one year from baseline to September-October 2017. RESULTS: In total, 2231 participants were included in our study, 29.1% of whom had manic/hypomanic episodes over the course of one year from baseline. Binomial logistic regression analysis revealed that the presence of manic/hypomanic episodes was correlated with lower baseline GAF scores, rapid cycling, personality disorder, bipolar I disorder, and a mood state with manic or mixed features. Substance abuse was also a risk factor for manic episodes. There was no significant association between a baseline antidepressant prescription and manic/hypomanic episodes. CONCLUSIONS: In Japan, 29.1% of outpatients with bipolar disorder had manic/hypomanic episodes over the course of one year. Our study suggested that a low GAF score, rapid cycling, personality disorder, bipolar I disorder, substance abuse, and baseline mood state could be predictors of manic/hypomanic episodes. Based on our findings, an antidepressant prescription is not a predictor of manic/hypomanic episodes.


Asunto(s)
Trastorno Bipolar/fisiopatología , Manía/fisiopatología , Adolescente , Adulto , Afecto , Factores de Edad , Anciano , Anciano de 80 o más Años , Antidepresivos/uso terapéutico , Trastorno Bipolar/complicaciones , Índice de Masa Corporal , Comorbilidad , Femenino , Indicadores de Salud , Humanos , Japón/epidemiología , Masculino , Persona de Mediana Edad , Pacientes Ambulatorios , Trastornos de la Personalidad/complicaciones , Prevalencia , Estudios Retrospectivos , Riesgo , Trastornos Relacionados con Sustancias/complicaciones , Encuestas y Cuestionarios , Resultado del Tratamiento , Adulto Joven
8.
Hum Psychopharmacol ; 36(2): e2764, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33089907

RESUMEN

OBJECTIVE: This study aims to clarify the relevant factors influencing practitioners' methods of prescribing medications for bipolar disorder, in a nation-wide survey in Japan. METHODS: The clinical records of 3130 outpatients with bipolar disorder were consecutively reviewed from 176 psychiatric outpatient clinics. Fifteen parameters, that is, five patients' including five general characteristics (sex, age, education, occupation, and social adjustment), five patients' aspects of mental functioning (onset age, comorbid mental illness, rapid-cycling, psychopathologic severity, and followed-up years), and five practitioners' characteristics (sex, age, specialist experience, clinic standing years, and location), were evaluated. The number of psychotropic drugs (mood stabilizers, antidepressants, antipsychotic drugs, anxiolytics, and hypnotics) was used as an index of pharmacotherapy. Converted data from each practitioner-unit were analyzed. RESULTS: Seven factors (patient's social adjustment, patient's psychopathology, patient's comorbid mental disorders, patient's followed-up years, doctor's age, clinic running years, and patient's education years) were correlated to the number of psychotropic drugs. Multiple regression analysis showed that the severity of illness (poor social adjustment, and comorbid mental illness) and an intractable disease course (long followed-up years), were significantly associated with the number of psychotropic drugs. CONCLUSION: Our findings indicated that patient-related conditions affected psychotropic polypharmacy more strongly than did practitioner-related conditions.


Asunto(s)
Antipsicóticos , Trastorno Bipolar , Antidepresivos/uso terapéutico , Antipsicóticos/uso terapéutico , Trastorno Bipolar/tratamiento farmacológico , Trastorno Bipolar/epidemiología , Humanos , Polifarmacia , Psicotrópicos/uso terapéutico
9.
BMC Psychiatry ; 20(1): 555, 2020 11 23.
Artículo en Inglés | MEDLINE | ID: mdl-33228573

RESUMEN

BACKGROUND: Several evidence-based practice guidelines have been developed to better treat bipolar disorder. However, the articles cited in these guidelines were not sufficiently based on real-world clinical practice. METHODS: The MUlticenter treatment SUrvey on BIpolar disorder in Japanese psychiatric clinics (MUSUBI) is a study conducted to accumulate evidence on the real-world practical treatment of bipolar disorder. Psychiatrists were asked to complete a questionnaire about patients with bipolar disorder by performing a retrospective medical record survey. The questionnaire included patient characteristics (age, gender, height, weight, academic background, and occupational status), comorbidities, mental status, treatment period, Global Assessment of Functioning (GAF) score, and details of pharmacological treatment. RESULTS: Data on 2705 patients were included in this study. The proportion of patients receiving antidepressant prescriptions was 40.9%. The most commonly used antidepressant was duloxetine, and the most frequently used antidepressant class was selective serotonin reuptake inhibitors (SSRIs). Binomial logistic regression analysis and bivariate analysis revealed that the usage of antidepressants was correlated with low prescription rates for mood stabilizers, high prescription rates for anxiolytics and hypnotics, and low GAF scores. In addition, patients in a depressive state had a significantly higher rate of antidepressant prescriptions than patients with other mental states. CONCLUSIONS: Approximately 40% of patients in Japan with a diagnosis of bipolar disorder have received antidepressants. Antidepressants were most often prescribed in combination with mood stabilizers, antipsychotics or both. Patients who were prescribed antidepressants received fewer mood stabilizers, more anxiolytics, and more hypnotics than those who did not receive antidepressant prescriptions.


Asunto(s)
Trastorno Bipolar , Antidepresivos/uso terapéutico , Trastorno Bipolar/tratamiento farmacológico , Humanos , Japón , Pacientes Ambulatorios , Estudios Retrospectivos
10.
Neuropsychiatr Dis Treat ; 16: 881-890, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32280229

RESUMEN

PURPOSE: The aim of this study was to identify factors associated with non-remission in bipolar disorder. PATIENTS AND METHODS: The multicenter treatment survey for bipolar disorder in psychiatric outpatient clinics (MUSUBI) study used a questionnaire administered at 176 clinics throughout Japan from September to October 2016. Clinic psychiatrists performed a retrospective medical record survey of consecutive cases with bipolar disorder. Patients were considered to be in remission if they met all of the following criteria: they were not in a mixed state, their manic or depressive symptoms were either borderline or nonexistent (corresponding to 2 or 1 points on the Clinical Global Impressions Scale, Bipolar Version), and their psychiatrists clinically considered them to be in remission. Enrolled patients were classified into remitters group and non-remitters group and demographic and clinical characteristics were contrasted between the groups. Non-remitters were compared with remitters, using a series of logistic regression analyses. RESULTS: A total of 3130 patients (1420 men; mean age: 50.3 years) were included in this study; 1307 patients (41.8%) were in remission. Of the remaining 1823 patients, 1260 (40.3%) had mild to severe depression, 261 (8.3%) suffered from manic or hypomanic episodes, and 302 (9.6%) were in a mixed state. Logistic regression analyses found the following eight factors to be significantly correlated with non-remission in patients with bipolar disorder: female gender, younger age, unemployed status, rapid cycling pattern, comorbid alcohol/substance abuse, poorer social function, lithium non-use, and antidepressant use. CONCLUSION: The MUSUBI study, the largest nationwide investigation on bipolar disorder, identified eight clinically relevant factors associated with non-remission in bipolar patients. They have important clinical implications; further prospective studies are necessary to replicate these findings and to guide better managements for those in serious needs.

11.
Plant Cell ; 30(11): 2663-2676, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30337427

RESUMEN

The secondary cell wall (SCW) of xylem vessel cells provides rigidity and strength that enables efficient water conduction throughout the plant. To gain insight into SCW deposition, we mutagenized Arabidopsis thaliana VASCULAR-RELATED NAC-DOMAIN7-inducible plant lines, in which ectopic protoxylem vessel cell differentiation is synchronously induced. The baculites mutant was isolated based on the absence of helical SCW patterns in ectopically-induced protoxylem vessel cells, and mature baculites plants exhibited an irregular xylem (irx) mutant phenotype in mature plants. A single nucleic acid substitution in the CELLULOSE SYNTHASE SUBUNIT 7 (CESA7) gene in baculites was identified: while the mutation was predicted to produce a C-terminal truncated protein, immunoblot analysis revealed that cesa7bac mutation results in loss of production of CESA7 proteins, indicating that baculites is a novel cesa7 loss-of-function mutant. In cesa7bac , despite a lack of patterned cellulose deposition, the helically-patterned deposition of other SCW components, such as the hemicellulose xylan and the phenolic polymer lignin, was not affected. Similar phenotypes were found in another point mutation mutant cesa7mur10-2 , and an established knock-out mutant, cesa7irx3-4 Taken together, we propose that the spatio-temporal deposition of different SCW components, such as xylan and lignin, is not dependent on cellulose patterning.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Celulosa/metabolismo , Lignina/metabolismo , Xilanos/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Regulación de la Expresión Génica de las Plantas , Glucosiltransferasas/genética , Glucosiltransferasas/metabolismo , Mutación
12.
Proc Natl Acad Sci U S A ; 115(27): E6366-E6374, 2018 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-29871949

RESUMEN

In plants, plasma membrane-embedded CELLULOSE SYNTHASE (CESA) enzyme complexes deposit cellulose polymers into the developing cell wall. Cellulose synthesis requires two different sets of CESA complexes that are active during cell expansion and secondary cell wall thickening, respectively. Hence, developing xylem cells, which first undergo cell expansion and subsequently deposit thick secondary walls, need to completely reorganize their CESA complexes from primary wall- to secondary wall-specific CESAs. Using live-cell imaging, we analyzed the principles underlying this remodeling. At the onset of secondary wall synthesis, the primary wall CESAs ceased to be delivered to the plasma membrane and were gradually removed from both the plasma membrane and the Golgi. For a brief transition period, both primary wall- and secondary wall-specific CESAs coexisted in banded domains of the plasma membrane where secondary wall synthesis is concentrated. During this transition, primary and secondary wall CESAs displayed discrete dynamic behaviors and sensitivities to the inhibitor isoxaben. As secondary wall-specific CESAs were delivered and inserted into the plasma membrane, the primary wall CESAs became concentrated in prevacuolar compartments and lytic vacuoles. This adjustment in localization between the two CESAs was accompanied by concurrent decreased primary wall CESA and increased secondary wall CESA protein abundance. Our data reveal distinct and dynamic subcellular trafficking patterns that underpin the remodeling of the cellulose biosynthetic machinery, resulting in the removal and degradation of the primary wall CESA complex with concurrent production and recycling of the secondary wall CESAs.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimología , Transdiferenciación Celular/fisiología , Glucosiltransferasas/metabolismo , Xilema/enzimología , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Glucosiltransferasas/genética , Xilema/genética
13.
J Exp Bot ; 69(8): 1849-1859, 2018 04 09.
Artículo en Inglés | MEDLINE | ID: mdl-29481639

RESUMEN

Lignin is an important phenolic biopolymer that provides strength and rigidity to the secondary cell walls of tracheary elements, sclereids, and fibers in vascular plants. Lignin precursors, called monolignols, are synthesized in the cell and exported to the cell wall where they are polymerized into lignin by oxidative enzymes such as laccases and peroxidases. In Arabidopsis thaliana, a peroxidase (PRX64) and laccase (LAC4) are shown to localize differently within cell wall domains in interfascicular fibers: PRX64 localizes to the middle lamella whereas LAC4 localizes throughout the secondary cell wall layers. Similarly, laccases localized to, and are responsible for, the helical depositions of lignin in protoxylem tracheary elements. In addition, we tested the mobility of laccases in the cell wall using fluorescence recovery after photobleaching. mCHERRY-tagged LAC4 was immobile in secondary cell wall domains, but mobile in the primary cell wall when ectopically expressed. A small secreted red fluorescent protein (sec-mCHERRY) was engineered as a control and was found to be mobile in both the primary and secondary cell walls. Unlike sec-mCHERRY, the tight anchoring of LAC4 to secondary cell wall domains indicated that it cannot be remobilized once secreted, and this anchoring underlies the spatial control of lignification.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimología , Pared Celular/metabolismo , Lacasa/metabolismo , Lignina/metabolismo , Peroxidasas/metabolismo , Arabidopsis/química , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/genética , Pared Celular/química , Pared Celular/genética , Regulación de la Expresión Génica de las Plantas , Lacasa/química , Lacasa/genética , Peroxidasas/química , Peroxidasas/genética , Dominios Proteicos , Transporte de Proteínas
14.
Ann Bot ; 121(6): 1107-1125, 2018 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-29415210

RESUMEN

Background: Secondary cell walls (SCWs) form the architecture of terrestrial plant biomass. They reinforce tracheary elements and strengthen fibres to permit upright growth and the formation of forest canopies. The cells that synthesize a strong, thick SCW around their protoplast must undergo a dramatic commitment to cellulose, hemicellulose and lignin production. Scope: This review puts SCW biosynthesis in a cellular context, with the aim of integrating molecular biology and biochemistry with plant cell biology. While SCWs are deposited in diverse tissue and cellular contexts including in sclerenchyma (fibres and sclereids), phloem (fibres) and xylem (tracheids, fibres and vessels), the focus of this review reflects the fact that protoxylem tracheary elements have proven to be the most amenable experimental system in which to study the cell biology of SCWs. Conclusions: SCW biosynthesis requires the co-ordination of plasma membrane cellulose synthases, hemicellulose production in the Golgi and lignin polymer deposition in the apoplast. At the plasma membrane where the SCW is deposited under the guidance of cortical microtubules, there is a high density of SCW cellulose synthase complexes producing cellulose microfibrils consisting of 18-24 glucan chains. These microfibrils are extruded into a cell wall matrix rich in SCW-specific hemicelluloses, typically xylan and mannan. The biosynthesis of eudicot SCW glucuronoxylan is taken as an example to illustrate the emerging importance of protein-protein complexes in the Golgi. From the trans-Golgi, trafficking of vesicles carrying hemicelluloses, cellulose synthases and oxidative enzymes is crucial for exocytosis of SCW components at the microtubule-rich cell membrane domains, producing characteristic SCW patterns. The final step of SCW biosynthesis is lignification, with monolignols secreted by the lignifying cell and, in some cases, by neighbouring cells as well. Oxidative enzymes such as laccases and peroxidases, embedded in the polysaccharide cell wall matrix, determine where lignin is deposited.


Asunto(s)
Pared Celular/metabolismo , Células Vegetales/metabolismo , Celulosa/biosíntesis , Aparato de Golgi/metabolismo , Lignina/biosíntesis , Plantas/metabolismo , Polisacáridos/biosíntesis
15.
Plant Physiol ; 166(2): 798-807, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25157028

RESUMEN

Plants precisely control lignin deposition in spiral or annular secondary cell wall domains during protoxylem tracheary element (TE) development. Because protoxylem TEs function to transport water within rapidly elongating tissues, it is important that lignin deposition is restricted to the secondary cell walls in order to preserve the plasticity of adjacent primary wall domains. The Arabidopsis (Arabidopsis thaliana) inducible VASCULAR NAC DOMAIN7 (VND7) protoxylem TE differentiation system permits the use of mutant backgrounds, fluorescent protein tagging, and high-resolution live-cell imaging of xylem cells during secondary cell wall development. Enzymes synthesizing monolignols, as well as putative monolignol transporters, showed a uniform distribution during protoxylem TE differentiation. By contrast, the oxidative enzymes LACCASE4 (LAC4) and LAC17 were spatially localized to secondary cell walls throughout protoxylem TE differentiation. These data support the hypothesis that precise delivery of oxidative enzymes determines the pattern of cell wall lignification. This view was supported by lac4lac17 mutant analysis demonstrating that laccases are necessary for protoxylem TE lignification. Overexpression studies showed that laccases are sufficient to catalyze ectopic lignin polymerization in primary cell walls when exogenous monolignols are supplied. Our data support a model of protoxylem TE lignification in which monolignols are highly mobile once exported to the cell wall, and in which precise targeting of laccases to secondary cell wall domains directs lignin deposition.


Asunto(s)
Pared Celular/metabolismo , Lacasa/metabolismo , Lignina/metabolismo , Xilema/metabolismo , Transportadoras de Casetes de Unión a ATP/metabolismo , Proteínas Fluorescentes Verdes/metabolismo , Polimerizacion
16.
Plant Physiol ; 164(3): 1250-60, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24468625

RESUMEN

Lipid secretion from epidermal cells to the plant surface is essential to create the protective plant cuticle. Cuticular waxes are unusual secretory products, consisting of a variety of highly hydrophobic compounds including saturated very-long-chain alkanes, ketones, and alcohols. These compounds are synthesized in the endoplasmic reticulum (ER) but must be trafficked to the plasma membrane for export by ATP-binding cassette transporters. To test the hypothesis that wax components are trafficked via the endomembrane system and packaged in Golgi-derived secretory vesicles, Arabidopsis (Arabidopsis thaliana) stem wax secretion was assayed in a series of vesicle-trafficking mutants, including gnom like1-1 (gnl1-1), transport particle protein subunit120-4, and echidna (ech). Wax secretion was dependent upon GNL1 and ECH. Independent of secretion phenotypes, mutants with altered ER morphology also had decreased wax biosynthesis phenotypes, implying that the biosynthetic capacity of the ER is closely related to its structure. These results provide genetic evidence that wax export requires GNL1- and ECH-dependent endomembrane vesicle trafficking to deliver cargo to plasma membrane-localized ATP-binding cassette transporters.


Asunto(s)
Arabidopsis/citología , Arabidopsis/metabolismo , Células Vegetales/metabolismo , Epidermis de la Planta/citología , Vesículas Transportadoras/metabolismo , Ceras/metabolismo , Red trans-Golgi/metabolismo , Proteínas de Arabidopsis/metabolismo , Membrana Celular/metabolismo , Retículo Endoplásmico/metabolismo , Retículo Endoplásmico/ultraestructura , Membranas Intracelulares/metabolismo , Mutación/genética , Tallos de la Planta/metabolismo , Tallos de la Planta/ultraestructura , Transporte de Proteínas
17.
Plant Cell Physiol ; 54(11): 1867-80, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24058145

RESUMEN

During cell wall biosynthesis, the Golgi apparatus is the platform for cell wall matrix biosynthesis and the site of packaging, of both matrix polysaccharides and proteins, into secretory vesicles with the correct targeting information. The objective of this study was to dissect the post-Golgi trafficking of cell wall polysaccharides using echidna as a vesicle traffic mutant of Arabidopsis thaliana and the pectin-secreting cells of the seed coat as a model system. ECHIDNA encodes a trans-Golgi network (TGN)-localized protein, which was previously shown to be required for proper structure and function of the secretory pathway. In echidna mutants, some cell wall matrix polysaccharides accumulate inside cells, rather than being secreted to the apoplast. In this study, live cell imaging of fluorescent protein markers as well as transmission electron microscopy (TEM)/immunoTEM of cryofixed seed coat cells were used to examine the consequences of TGN disorganization in echidna mutants under conditions of high polysaccharide production and secretion. While in wild-type seed coat cells, pectin is secreted to the apical surface, in echidna, polysaccharides accumulate in post-Golgi vesicles, the central lytic vacuole and endoplasmic reticulum-derived bodies. In contrast, proteins were partially mistargeted to internal multilamellar membranes in echidna. These results suggest that while secretion of both cell wall polysaccharides and proteins at the TGN requires ECHIDNA, different vesicle trafficking components may mediate downstream events in their secretion from the TGN.


Asunto(s)
Arabidopsis/metabolismo , Pectinas/metabolismo , Polisacáridos/metabolismo , Vesículas Transportadoras/metabolismo , Vacuolas/metabolismo , Red trans-Golgi/metabolismo , Arabidopsis/genética , Arabidopsis/ultraestructura , Transporte Biológico , Membrana Celular/metabolismo , Pared Celular/metabolismo , Retículo Endoplásmico/metabolismo , Aparato de Golgi/metabolismo , Mutación , Fenotipo , Mucílago de Planta/metabolismo , Semillas/genética , Semillas/metabolismo , Semillas/ultraestructura
18.
Plant Cell ; 25(7): 2633-46, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23832588

RESUMEN

The secretion of cell wall polysaccharides through the trans-Golgi network (TGN) is required for plant cell elongation. However, the components mediating the post-Golgi secretion of pectin and hemicellulose, the two major cell wall polysaccharides, are largely unknown. We identified evolutionarily conserved YPT/RAB GTPase Interacting Protein 4a (YIP4a) and YIP4b (formerly YIP2), which form a TGN-localized complex with ECHIDNA (ECH) in Arabidopsis thaliana. The localization of YIP4 and ECH proteins at the TGN is interdependent and influences the localization of VHA-a1 and SYP61, which are key components of the TGN. YIP4a and YIP4b act redundantly, and the yip4a yip4b double mutants have a cell elongation defect. Genetic, biochemical, and cell biological analyses demonstrate that the ECH/YIP4 complex plays a key role in TGN-mediated secretion of pectin and hemicellulose to the cell wall in dark-grown hypocotyls and in secretory cells of the seed coat. In keeping with these observations, Fourier transform infrared microspectroscopy analysis revealed that the ech and yip4a yip4b mutants exhibit changes in their cell wall composition. Overall, our results reveal a TGN subdomain defined by ECH/YIP4 that is required for the secretion of pectin and hemicellulose and distinguishes the role of the TGN in secretion from its roles in endocytic and vacuolar trafficking.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Pared Celular/metabolismo , Polisacáridos/metabolismo , Red trans-Golgi/metabolismo , Secuencia de Aminoácidos , Arabidopsis/genética , Proteínas de Arabidopsis/clasificación , Proteínas de Arabidopsis/genética , Pared Celular/genética , Proteínas Luminiscentes/genética , Proteínas Luminiscentes/metabolismo , Microscopía Confocal , Datos de Secuencia Molecular , Complejos Multiproteicos/genética , Complejos Multiproteicos/metabolismo , Mutación , Filogenia , Plantas Modificadas Genéticamente , Unión Proteica , Homología de Secuencia de Aminoácido , Técnicas del Sistema de Dos Híbridos
19.
Int J Psychiatry Med ; 46(2): 153-67, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24552039

RESUMEN

OBJECTIVES: We previously reported that many non-psychiatric doctors in Japan believe that treating depression was not part of their duties. Educational interventions must address motivation of physicians to play a role in depression care. In this study, we explored factors associated with perceived feasibility and willingness of non-psychiatric doctors in Japan to treat depression. METHODS: The study population included non-psychiatric doctors of the General Physician-Psychiatrist (G-P) Network group in Japan. We explored perceived feasibility and willingness to treat depressed patients, and examined preliminary associations with attitudes toward depression (the Depression Attitude Questionnaire: DAQ) and current depression treatment in routine medical practice. RESULTS: Responses were obtained from 56 non-psychiatric doctors (response rate: 35.4%). The doctors who scored high on the "Professional" and "Pessimism" subscale of the DAQ believed that treating depressed patients was not feasible (chi2 = 13.6, p < 0.01; chi2 = 7.3, p < 0.05, respectively) and were not willing to treat depressed patients (chi2 = 9.4, p < 0.01; chi2 = 6.6, p < 0.05, respectively) as part of their routine medical practice. The doctors who scored high on the "Professional" subscale referred fewer depressed patients to psychiatrists (r = -0.33, p < 0.05), and those who scored high on the "Pessimism" subscale recognized fewer depressed patients (r = -0.39, p < 0.01). CONCLUSIONS: The present study showed that attitudes toward depression were associated with perceived feasibility and willingness to treat depressed patients and with under-diagnosis of depression. Educational interventions optimized for these attitudes should be developed to improve recognition and treatment of depression in Japan.


Asunto(s)
Actitud del Personal de Salud , Depresión/terapia , Médicos/psicología , Adulto , Depresión/diagnóstico , Femenino , Conocimientos, Actitudes y Práctica en Salud , Humanos , Japón , Masculino , Persona de Mediana Edad , Médicos/normas
20.
BMC Res Notes ; 5: 441, 2012 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-22894761

RESUMEN

BACKGROUND: Under-recognition of depression is common in many countries. Education of medical staff, focusing on their attitudes towards depression, may be necessary to change their behavior and enhance recognition of depression. Several studies have previously reported on attitudes toward depression among general physicians. However, little is known about attitudes of non-psychiatric doctors in Japan. In the present study, we surveyed non-psychiatric doctors' attitude toward depression. METHODS: The inclusion criteria of participants in the present study were as follows: 1) Japanese non-psychiatric doctors and 2) attendees in educational opportunities regarding depression care. We conveniently approached two populations: 1) a workshop to depression care for non-psychiatric doctors and 2) a general physician-psychiatrist (G-P) network group. We contacted 367 subjects. Attitudes toward depression were measured using the Depression Attitude Questionnaire (DAQ), a 20-item self-report questionnaire developed for general physicians. We report scores of each DAQ item and factors derived from exploratory factor analysis. RESULTS: We received responses from 230 subjects, and we used DAQ data from 187 non-psychiatric doctors who met the inclusion criteria. All non-psychiatric doctors (n = 187) disagreed with "I feel comfortable in dealing with depressed patients' needs," while 60 % (n = 112) agreed with "Working with depressed patients is heavy going." Factor analysis indicated these items comprised a factor termed "Depression should be treated by psychiatrists" - to which 54 % of doctors (n = 101) agreed. Meanwhile, 67 % of doctors (n = 126) thought that nurses could be useful in depressed patient support. The three factors derived from the Japanese DAQ differed from models previously derived from British GP samples. The attitude of Japanese non-psychiatric doctors concerning whether depression should be treated by psychiatrists was markedly different to that of British GPs. CONCLUSIONS: Japanese non-psychiatric doctors believe that depression care is beyond the scope of their duties. It is suggested that educational programs or guidelines for depression care developed in other countries such as the UK are not directly adaptable for Japanese non-psychiatric doctors. Developing a focused educational program that motivates non-psychiatric doctors to play a role in depression care is necessary to enhance recognition and treatment of depression in Japan.


Asunto(s)
Pueblo Asiatico/psicología , Actitud del Personal de Salud , Depresión/psicología , Conocimientos, Actitudes y Práctica en Salud , Médicos/psicología , Adulto , Anciano , Anciano de 80 o más Años , Estudios Transversales , Depresión/diagnóstico , Depresión/terapia , Análisis Factorial , Femenino , Humanos , Japón/epidemiología , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios
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