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1.
Chinese Journal of Biotechnology ; (12): 81-93, 2024.
Article in Chinese | WPRIM | ID: wpr-1008081

ABSTRACT

The chloroplast genome encodes many key proteins involved in photosynthesis and other metabolic processes, and metabolites synthesized in chloroplasts are essential for normal plant growth and development. Root-UVB (ultraviolet radiation B)-sensitive (RUS) family proteins composed of highly conserved DUF647 domain belong to chloroplast proteins. They play an important role in the regulation of various life activities such as plant morphogenesis, material transport and energy metabolism. This article summarizes the recent advances of the RUS family proteins in the growth and development of plants such as embryonic development, photomorphological construction, VB6 homeostasis, auxin transport and anther development, with the aim to facilitate further study of its molecular regulation mechanism in plant growth and development.


Subject(s)
Female , Pregnancy , Humans , Ultraviolet Rays , Biological Transport , Chloroplasts/genetics , Embryonic Development , Plant Development/genetics
2.
Biol. Res ; 57: 1-1, 2024. ilus, graf
Article in English | LILACS | ID: biblio-1550056

ABSTRACT

BACKGROUND: Tumor-derived small extracellular vesicles (sEVs) can promote tumorigenic and metastatic capacities in less aggressive recipient cells mainly through the biomolecules in their cargo. However, despite recent advances, the specific molecules orchestrating these changes are not completely defined. Lactadherin is a secreted 0protein typically found in the milk fat globule membrane. Its overexpression has been associated with increased tumorigenesis and metastasis in breast cancer (BC) and other tumors. However, neither its presence in sEVs secreted by BC cells, nor its role in sEV-mediated intercellular communication have been described. The present study focused on the role of lactadherin-containing sEVs from metastatic MDA-MB-231 triple-negative BC (TNBC) cells (sEV-MDA231) in the promotion of pro-metastatic capacities in non-tumorigenic and non-metastatic recipient cells in vitro, as well as their pro-metastatic role in a murine model of peritoneal carcinomatosis. RESULTS: We show that lactadherin is present in sEVs secreted by BC cells and it is higher in sEV-MDA231 compared with the other BC cell-secreted sEVs measured through ELISA. Incubation of non-metastatic recipient cells with sEV- MDA231 increases their migration and, to some extent, their tumoroid formation capacity but not their anchorage-independent growth. Remarkably, lactadherin blockade in sEV-MDA231 results in a significant decrease of those sEV-mediated changes in vitro. Similarly, intraperitoneally treatment of mice with MDA-MB-231 BC cells and sEV-MDA231 greatly increase the formation of malignant ascites and tumor micronodules, effects that were significantly inhibited when lactadherin was previously blocked in those sEV-MDA231. CONCLUSIONS: As to our knowledge, our study provides the first evidence on the role of lactadherin in metastatic BC cell-secreted sEVs as promoter of: (i) metastatic capacities in less aggressive recipient cells, and ii) the formation of malignant ascites and metastatic tumor nodules. These results increase our understanding on the role of lactadherin in sEVs as promoter of metastatic capacities which can be used as a therapeutic option for BC and other malignancies.


Subject(s)
Humans , Animals , Mice , Ascites , Extracellular Vesicles , Biological Transport , Cell Communication , Cell Line, Tumor , Carcinogenesis
3.
Chinese Journal of Biotechnology ; (12): 3494-3507, 2023.
Article in Chinese | WPRIM | ID: wpr-1007972

ABSTRACT

Aminopeptidase A (Pep A) is a metal-dependent enzyme that specifically hydrolyze peptides with the N-terminal amino acids glutamic acid (Glu) and aspartic acid (Asp). A possible application of PepA is the hydrolysis of Glu/Asp-rich food proteins such as wheat gluten and casein, increasing the flavor and solubility of food protein. In the present study, the gene encoding a Pep A from Lactococcus lactis ssp. lactis IL1403 was synthesized and introduced into Pichia pastoris GS115 (His4). Lc-Pep A was successfully expressed and secreted to the culture medium, followed by identification and purification to homogeneity. Characteristics study demonstrated that Lc-Pep A could specifically hydrolyze the substrates Glu-pNA and Asp-pNA with similar catalytic activity, and this was further confirmed by the kinetics parameters measured. Additionally, Lc-Pep A showed a broad thermostability and pH stability with an optimum temperature of 60 ℃ and an optimum pH of 8.0. The enzyme activity of Lc-Pep A was activated by metal ions Co2+, Mn2+, and Zn2+ but was strongly inhibited by Ni2+and Cu2+. The routine proteinase inhibitor had no effect on the activity of Lc-Pep A. However, Lc-Pep A was strongly inhibited by the metallopeptidase inhibitor, EDTA, and disulfide bond-reducing agents. The study may facilitate production and application of Lc-Pep A.


Subject(s)
Glutamyl Aminopeptidase , Lactococcus lactis/genetics , Biological Transport , Culture Media , Glutamic Acid
4.
Chinese Journal of Biotechnology ; (12): 3204-3218, 2023.
Article in Chinese | WPRIM | ID: wpr-1007953

ABSTRACT

Sterols are a class of cyclopentano-perhydrophenanthrene derivatives widely present in living organisms. Sterols are important components of cell membranes. In addition, they also have important physiological and pharmacological activities. With the development of synthetic biology and metabolic engineering technology, yeast cells are increasingly used for the heterologous synthesis of sterols in recent years. Nevertheless, since sterols are hydrophobic macromolecules, they tend to accumulate in the membrane fraction of yeast cells and consequently trigger cytotoxicity, which hampers the further improvement of sterols yield. Therefore, revealing the mechanism of sterol transport in yeast, especially understanding the working principle of sterol transporters, is vital for designing strategies to relieve the toxicity of sterol accumulation and increasing sterol yield in yeast cell factories. In yeast, sterols are mainly transported through protein-mediated non-vesicular transport mechanisms. This review summarizes five types of sterol transport-related proteins that have been reported in yeast, namely OSBP/ORPs family proteins, LAM family proteins, ABC transport family proteins, CAP superfamily proteins, and NPC-like sterol transport proteins. These transporters play important roles in intracellular sterol gradient distribution and homeostasis maintenance. In addition, we also review the current status of practical applications of sterol transport proteins in yeast cell factories.


Subject(s)
Saccharomyces cerevisiae/genetics , Sterols , Phytosterols , Biological Transport , ATP-Binding Cassette Transporters/genetics
5.
Chinese Journal of Biotechnology ; (12): 961-977, 2023.
Article in Chinese | WPRIM | ID: wpr-970416

ABSTRACT

Aromatic compounds are a class of organic compounds with benzene ring(s). Aromatic compounds are hardly decomposed due to its stable structure and can be accumulated in the food cycle, posing a great threat to the ecological environment and human health. Bacteria have a strong catabolic ability to degrade various refractory organic contaminants (e.g., polycyclic aromatic hydrocarbons, PAHs). The adsorption and transportation are prerequisites for the catabolism of aromatic compounds by bacteria. While remarkable progress has been made in understanding the metabolism of aromatic compounds in bacterial degraders, the systems responsible for the uptake and transport of aromatic compounds are poorly understood. Here we summarize the effect of cell-surface hydrophobicity, biofilm formation, and bacterial chemotaxis on the bacterial adsorption of aromatic compounds. Besides, the effects of outer membrane transport systems (such as FadL family, TonB-dependent receptors, and OmpW family), and inner membrane transport systems (such as major facilitator superfamily (MFS) transporter and ATP-binding cassette (ABC) transporter) involved in the membrane transport of these compounds are summarized. Moreover, the mechanism of transmembrane transport is also discussed. This review may serve as a reference for the prevention and remediation of aromatic pollutants.


Subject(s)
Humans , Adsorption , Bacteria/metabolism , Organic Chemicals , Biological Transport , ATP-Binding Cassette Transporters , Polycyclic Aromatic Hydrocarbons/metabolism
6.
Asian Journal of Andrology ; (6): 238-242, 2022.
Article in English | WPRIM | ID: wpr-928542

ABSTRACT

Cilium, an organelle with a unique proteome and organization, protruding from the cell surface, generally serves as a force generator and signaling compartment. During ciliogenesis, ciliary proteins are synthesized in cytoplasm and transported into cilia by intraflagellar transport (IFT) particles, where the inner counterparts undergo reverse trafficking. The homeostasis of IFT plays a key role in cilial structure assembly and signaling transduction. Much progress has been made on the mechanisms and functions of IFT; however, recent studies have revealed the involvement of IFT particle subunits in organogenesis and spermatogenesis. In this review, we discuss new concepts concerning the molecular functions of IFT protein IFT25 and how its interactions with other IFT particle subunits are involved in mammalian development and fertility.


Subject(s)
Animals , Male , Biological Transport , Carrier Proteins/metabolism , Cilia/metabolism , Flagella/metabolism , Mammals/metabolism , Organogenesis , Proteins/metabolism , Signal Transduction
7.
Biol. Res ; 55: 35-35, 2022. ilus
Article in English | LILACS | ID: biblio-1429901

ABSTRACT

Extracellular vesicles (EVs) are naturally released membrane vesicles that act as carriers of proteins and RNAs for intercellular communication. With various biomolecules and specific ligands, EV has represented a novel form of information transfer, which possesses extremely outstanding efficiency and specificity compared to the classical signal transduction. In addition, EV has extended the concept of signal transduction to intercellular aspect by working as the collection of extracellular information. Therefore, the functions of EVs have been extensively characterized and EVs exhibit an exciting prospect for clinical applications. However, the biogenesis of EVs and, in particular, the regulation of this process by extracellular signals, which are essential to conduct further studies and support optimal utility, remain unclear. Here, we review the current understanding of the biogenesis of EVs, focus on the regulation of this process by extracellular signals and discuss their therapeutic value.


Subject(s)
Extracellular Vesicles/metabolism , Biological Transport , RNA/metabolism , Signal Transduction , Cell Communication/physiology
8.
Rev. peru. med. exp. salud publica ; 38(1): 143-152, ene-mar 2021. tab, graf
Article in Spanish | LILACS | ID: biblio-1280560

ABSTRACT

RESUMEN La Organización Mundial de la Salud (OMS) ubica a la tuberculosis (TB) como uno de los problemas de salud más preocupantes en la actualidad, y señala que se requieren de acciones novedosas para controlar su expansión y, de esta manera, alcanzar una de las metas establecidas en los Objetivos de Desarrollo Sostenible: reducir para 2030 la morbilidad e incidencia de TB. Para lograr este objetivo, está claro que las herramientas empleadas actualmente para su diagnóstico y tratamiento ya no son las adecuadas. En este sentido, es necesario desarrollar nuevos medicamentos y vacunas, así como novedosos procedimientos de administración de fármacos que generen una mejor respuesta, disminuyan el tiempo y optimicen los tratamientos. La nanotecnología ha incorporado en los últimos años un gran número de nuevas herramientas que incrementan considerablemente, la diversidad de mecanismos para la administración de tratamientos antituberculosos. Dicho esto, la presente revisión describe brevemente el estado actual de la farmacorresistencia en TB, así como las características generales de las nanopartículas que están evaluándose como herramientas para transportar antibióticos antituberculosos.


ABSTRACT The World Health Organization (WHO) places Tuberculosis (TB) as one of the most important health problems today. According to the WHO, this disease requires novel actions to control its expansion and, in this way, achieve one of the goals established in the sustainable development goals: to reduce TB morbidity and incidence by 2030 and regain control. To achieve this goal, the tools currently used for diagnosis and treatment are no longer adequate. In this sense, it is necessary to develop new drugs and vaccines, as well as novel drug administration procedures that generate a better response, reduce times, and optimize treatments. Nanotechnology has incorporated in recent years a considerable number of new tools that significantly increase the diversity of mechanisms for the administration of anti-tuberculosis drugs. Therefore, the present review briefly describes the current state of drug resistance in tuberculosis, as well as the general characteristics of nanoparticles being evaluated as tools to transport new antibiotics against tuberculosis.


Subject(s)
Tuberculosis , Nanoparticles , Antibiotics, Antitubercular , Biological Transport , Drug Resistance, Microbial , Drug Carriers , Morbidity , Anti-Infective Agents
9.
Rev. peru. med. exp. salud publica ; 38(1): 143-152, ene-mar 2021. tab, graf
Article in Spanish | LILACS | ID: biblio-1280577

ABSTRACT

RESUMEN La Organización Mundial de la Salud (OMS) ubica a la tuberculosis (TB) como uno de los problemas de salud más preocupantes en la actualidad, y señala que se requieren de acciones novedosas para controlar su expansión y, de esta manera, alcanzar una de las metas establecidas en los Objetivos de Desarrollo Sostenible: reducir para 2030 la morbilidad e incidencia de TB. Para lograr este objetivo, está claro que las herramientas empleadas actualmente para su diagnóstico y tratamiento ya no son las adecuadas. En este sentido, es necesario desarrollar nuevos medicamentos y vacunas, así como novedosos procedimientos de administración de fármacos que generen una mejor respuesta, disminuyan el tiempo y optimicen los tratamientos. La nanotecnología ha incorporado en los últimos años un gran número de nuevas herramientas que incrementan considerablemente, la diversidad de mecanismos para la administración de tratamientos antituberculosos. Dicho esto, la presente revisión describe brevemente el estado actual de la farmacorresistencia en TB, así como las características generales de las nanopartículas que están evaluándose como herramientas para transportar antibióticos antituberculosos.


ABSTRACT The World Health Organization (WHO) places Tuberculosis (TB) as one of the most important health problems today. According to the WHO, this disease requires novel actions to control its expansion and, in this way, achieve one of the goals established in the sustainable development goals: to reduce TB morbidity and incidence by 2030 and regain control. To achieve this goal, the tools currently used for diagnosis and treatment are no longer adequate. In this sense, it is necessary to develop new drugs and vaccines, as well as novel drug administration procedures that generate a better response, reduce times, and optimize treatments. Nanotechnology has incorporated in recent years a considerable number of new tools that significantly increase the diversity of mechanisms for the administration of anti-tuberculosis drugs. Therefore, the present review briefly describes the current state of drug resistance in tuberculosis, as well as the general characteristics of nanoparticles being evaluated as tools to transport new antibiotics against tuberculosis.


Subject(s)
Tuberculosis , Drug Resistance, Microbial , Nanoparticles , Biological Transport , Pharmaceutical Preparations , Morbidity , Anti-Infective Agents , Antibiotics, Antitubercular
10.
Chinese Journal of Medical Genetics ; (6): 907-911, 2021.
Article in Chinese | WPRIM | ID: wpr-921967

ABSTRACT

ABCC1 gene is expressed in various tissues and organs of the human body, and can transport substrates including drugs, heavy metals, toxic substances and organic anions. Previous research on ABCC1 gene has mostly focused on tumor multidrug resistance. Recently, ABCC1 has been proposed as a candidate gene for hereditary hearing impairment, which has attracted much attention. ABCC1-associated deafness may be related to its role in biological barriers. This article has summarized recent progress in the study of the role of ABCC1 in the blood-testis barrier, placental barrier, blood-brain barrier, blood-labyrinth barrier, which may provide insight into its biological functions.


Subject(s)
Female , Humans , Male , Pregnancy , Biological Transport , Deafness/genetics , Multidrug Resistance-Associated Proteins/genetics , Placenta
11.
Chinese Journal of Biotechnology ; (12): 3020-3030, 2021.
Article in Chinese | WPRIM | ID: wpr-921403

ABSTRACT

P1B-ATPases are a group of proteins that can transport heavy metal ions across membranes by hydrolyzing ATP and they are a subclass of the P-type ATPase family. It was found that P1B-ATPases are mainly responsible for the active transport of heavy metal ions in plants and play an important role in the regulation of heavy metal homeostasis in plants. In this paper, we dissusses the mechanism of P1B-ATPases from the structure and classification of P1B-ATPases, and review the current research progress in the function of P1B-ATPases, in order to provide reference for future research and application of P1B-ATPases in improving crop quality and ecological environment management.


Subject(s)
Adenosine Triphosphatases/metabolism , Biological Transport , Metals, Heavy , Plants/enzymology
12.
China Journal of Chinese Materia Medica ; (24): 1795-1802, 2021.
Article in Chinese | WPRIM | ID: wpr-879094

ABSTRACT

This article aims to investigate the ameliorative effect of Linderae Radix ethanol extract on hyperlipidemia rats induced by high-fat diet and to explore its possible mechanism from the perspective of reverse cholesterol transport(RCT). SD rats were divided into normal group, model group, atorvastatin group, Linderae Radix ethanol extract(LREE) of high, medium, low dose groups. Except for the normal group, the other groups were fed with a high-fat diet to establish hyperlipidemia rat models; the normal group and the model group were given pure water, while each administration group was given corresponding drugs by gavage once a day for five weeks. Serum total cholesterol(TC), triglyceride(TG), high density lipoprotein-cholesterol(HDL-c), low density lipoprotein-cholesterol(LDL-c), alanine aminotransferase(ALT), and aspartate aminotransferase(AST) levels were measured by automatic blood biochemistry analyzer; the contents of TC, TG, total bile acid(TBA) in liver and TC and TBA in feces of rats were detected by enzyme colorimetry. HE staining was used to observe the liver tissue lesions; immunohistochemistry was used to detect the expression of ATP-binding cassette G8(ABCG8) in small intestine; Western blot and immunohistochemistry were used to detect the expression of peroxisome proliferator-activated receptor gamma/aerfa(PPARγ/α), liver X receptor-α(LXRα), ATP-binding cassette A1(ABCA1) pathway protein and scavenger receptor class B type Ⅰ(SR-BⅠ) in liver. The results showed that LREE could effectively reduce serum and liver TC, TG levels, serum LDL-c levels and AST activity, and increase HDL-c levels, but did not significant improve ALT activity and liver index; HE staining results showed that LREE could reduce liver lipid deposition and inflammatory cell infiltration. In addition, LREE also increased the contents of fecal TC and TBA, and up-regulated the protein expressions of ABCG8 in small intestine and PPARγ/α, SR-BⅠ, LXRα, and ABCA1 in liver. LREE served as a positive role on hyperlipidemia model rats induced by high-fat diet, which might be related to the regulation of RCT, the promotion of the conversion of cholesterol to the liver and bile acids, and the intestinal excretion of cholesterol and bile acids. RCT regulation might be a potential mechanism of LREE against hyperlipidemia.


Subject(s)
Animals , Rats , Biological Transport , Cholesterol/metabolism , Diet, High-Fat/adverse effects , Hyperlipidemias/metabolism , Liver/metabolism , Rats, Sprague-Dawley , Triglycerides/metabolism
13.
China Journal of Chinese Materia Medica ; (24): 52-56, 2021.
Article in Chinese | WPRIM | ID: wpr-878910

ABSTRACT

ATP-binding cassette(ABC) transporters are one of the largest protein families in organisms, with important effects in regulating plant growth and development, root morphology, transportation of secondary metabolites and resistance of stress. Environmental stress promotes the biosynthesis and accumulation of secondary metabolites, which determines the quality of medicinal plants. Therefore, how to improve the accumulation of secondary metabolites has been a hotspot in studying medicinal plants. Many studies have showed that ABC transporters are extremely related to the transportation and accumulation of secondary metabolites in plants. Recently, with the great development of genomics and transcriptomic sequencing technology, the regulatory mechanisms of ABC transporters on secondary metabolites have attached great attentions in medicinal plants. This paper reviewed the mechanisms of different groups of ABC transporters in transporting secondary metabolites through cell membranes. This paper provided key theoretical basis and technical supports in studying the mechanisms of ABC transporters in medicinal plant, and promoting the accumulation of secondary metabolites, in order to improve the quality of medicinal plants.


Subject(s)
ATP-Binding Cassette Transporters/metabolism , Biological Transport , Plant Development , Plants, Medicinal/metabolism , Stress, Physiological
14.
Acta Physiologica Sinica ; (6): 681-689, 2021.
Article in Chinese | WPRIM | ID: wpr-887702

ABSTRACT

Prostaglandin E2 (PGE2), a bioactive lipid mediator, is one of the most important locally acting factors involved in a variety of physiological and pathophysiological processes. PGE2 binds with four EP receptors (EP1-4) to activate G protein-coupled receptor signaling responses. Recent functional and molecular studies have revealed that PGE2 plays an essential role in regulation of renal fluid transport via a variety of mechanisms. The water balance mainly depends on the regulation of aquaporin-2 (AQP2) by arginine vasopressin (AVP) in renal collecting duct principal cells. In recent years, increasing evidence suggests that PGE2 plays an important role in renal water reabsorption in the collecting ducts. In this paper, we reviewed the role of PGE2 and its receptors in the regulation of water reabsorption in the kidney, which may provide a new therapeutic strategy for many diseases especially nephrogenic diabetes insipidus.


Subject(s)
Humans , Aquaporin 2/metabolism , Biological Transport , Diabetes Insipidus, Nephrogenic , Dinoprostone , Water/metabolism
15.
China Journal of Chinese Materia Medica ; (24): 167-174, 2019.
Article in Chinese | WPRIM | ID: wpr-771502

ABSTRACT

To investigate the active fraction from Bletilla striata in Caco-2 cell monolayer,so as to explore its absorption mechanism of oral administration preliminarily.Active fraction from B.striata in Caco-2 cell monolayer was analyzed by UPLC-Q-TOF and detected by UPLC-MS/MS,and the effects of different concentrations,pH and P-glycoprotein inhibitors on Caco-2 cells Monolayer were investigated.Six compounds were isolated from the active fraction of B.striata in Caco-2 cell monolayer by UPLC-Q-TOF,and identified as B6,B12,B14,B17,B19 and B23,with concentration dependence.Within the 0-180 min,the uptake of B12 and B14 had a time dependence,while B6,B17,B19 and B23 tended to saturate after 60 min.All of the components had a good absorption in an acidic environment.B6 had a good absorption at pH 6.0,while the other components B12,B14,B17,B19 and B23 had a good absorption at pH4.0.The absorption of the 6 main components of B.striata were not be affected by P-glycoprotein inhibitors(verapamil/cyclosporin A).Compared with the control group,there was no difference in the absorption of B6 and B12,and the absorption of B14,B17,B19 and B23 increased,but with no significant difference.The absorption characteristic of B.striata extract across the Caco-2 cell monolayer is probably passive diffusion,and the absorption process was not affected by P-glycoprotein.


Subject(s)
Humans , Biological Transport , Caco-2 Cells , Chromatography, Liquid , Intestinal Absorption , Orchidaceae , Chemistry , Plant Extracts , Pharmacology , Tandem Mass Spectrometry
16.
Acta Physiologica Sinica ; (6): 350-360, 2019.
Article in Chinese | WPRIM | ID: wpr-777179

ABSTRACT

Facilitative glucose transporters (GLUT) are proteins that mediate glucose transmembrane transport in the form of facilitated diffusion, which play an important role in regulating cell energy metabolism. There are many breakthroughs in researches of facilitative GLUT in recent years. It has been known that there are 14 subtypes of facilitative GLUT with obvious tissue specificity in distribution and physiological function. In the present review, the tissue and cellular distribution, subcellular localization, expression regulation, physiological function and the relationship to diseases of facilitative GLUT subtypes were summarized, in order to further understand their physiological and pathophysiological significances.


Subject(s)
Humans , Biological Transport , Disease , Energy Metabolism , Glucose , Glucose Transport Proteins, Facilitative , Physiology
17.
Chinese Journal of Biotechnology ; (12): 1162-1173, 2019.
Article in Chinese | WPRIM | ID: wpr-771812

ABSTRACT

Cell-penetrating peptides (CPPs) are short peptides that can penetrate the cell membrane or tissue barrier. CPPs can deliver a variety of biomacromolecules, such as proteins, RNA and DNA, into cells to produce intracellular functional effects. Endocytosis and direct penetration have been suggested as the two major uptake mechanisms for CPPs-mediated cargo delivery. Compared with other non-natural chemical molecules-based delivery reagents, the CPPs have better biocompatibility, lower cytotoxicity, are easily degraded after cargo delivery, and can be fused and recombined expressed with bioactive proteins. Because of these advantages, the CPPs have become an important potential tool for delivery of developing drugs which targets intracellular factors. As a novel delivery tool, the CPPs also show promising application prospects in biomedical researches. This review summarized recent advances regarding the classification characteristics, the cellular uptake mechanisms and therapeutic application potentials of CPPs.


Subject(s)
Biological Transport , Cell Membrane , Cell-Penetrating Peptides , Metabolism , Endocytosis
18.
Journal of Zhejiang University. Science. B ; (12): 513-527, 2019.
Article in English | WPRIM | ID: wpr-776711

ABSTRACT

Aluminum (Al) is the most abundant metal element in the earth's crust. On acid soils, at pH 5.5 or lower, part of insoluble Al-containing minerals become solubilized into soil solution, with resultant highly toxic effects on plant growth and development. Nevertheless, some plants have developed Al-tolerance mechanisms that enable them to counteract this Al toxicity. One such well-documented mechanism is the Al-induced secretion of organic acid anions, including citrate, malate, and oxalate, from plant roots. Once secreted, these anions chelate external Al ions, thus protecting the secreting plant from Al toxicity. Genes encoding the citrate and malate transporters responsible for secretion have been identified and characterized, and accumulating evidence indicates that regulation of the expression of these transporter genes is critical for plant Al tolerance. In this review, we outline the recent history of research into plant Al-tolerance mechanisms, with special emphasis on the physiology of Al-induced secretion of organic acid anions from plant roots. In particular, we summarize the identification of genes encoding organic acid transporters and review current understanding of genes regulating organic acid secretion. We also discuss the possible signaling pathways regulating the expression of organic acid transporter genes.


Subject(s)
Aluminum , Toxicity , Anions , Biological Transport , Citric Acid , Metabolism , Malates , Metabolism , Oxalic Acid , Metabolism , Plant Roots , Metabolism , Signal Transduction , Physiology
19.
Adv Rheumatol ; 59: 20, 2019. tab
Article in English | LILACS | ID: biblio-1088591

ABSTRACT

Abstract Background: To date there are no specific classification criteria for childhood-onset systemic lupus erythematosus (cSLE). This study aims to compare the performance among the American College of Rheumatology (ACR) 1997, the Systemic Lupus International Collaborating Clinics criteria (SLICC) and the new European League Against Rheumatism (EULAR)/ACR criteria, in a cSLE cohort. Methods: We conducted a medical chart review study of cSLE cases and controls with defined rheumatic diseases, both ANA positive, to establish each ACR1997, SLICC and EULAR/ACR criterion fulfilled, at first visit and 1-year-follow-up. Results: Study population included 122 cSLE cases and 89 controls. At first visit, SLICC criteria had higher sensitivity than ACR 1997 (89.3% versus 70.5%, p < 0.001), but similar specificity (80.9% versus 83.2%, p = 0.791), however performance was not statistically different at 1-year-follow-up. SLICC better scored in specificity compared to EULAR/ACR score ≥ 10 at first visit (80.9% versus 67.4%, p = 0.008) and at 1-year (76.4% versus 58.4%, p = 0.001), although sensitivities were similar. EULAR/ACR criteria score ≥ 10 exhibited higher sensitivity than ACR 1997 (87.7% versus 70.5%, p < 0.001) at first visit, but comparable at 1-year, whereas specificity was lower at first visit (67.4% versus 83.2%, p = 0.004) and 1-year (58.4% versus 76.4%, p = 0.002). A EULAR/ACR score ≥ 13 against a score ≥ 10, resulted in higher specificity, positive predictive value, and cut-off point accuracy. Compared to SLICC, a EULAR/ACR score ≥ 13 resulted in lower sensitivity at first visit (76.2% versus 89.3%, p < 0.001) and 1-year (91% versus 97.5%, p = 0.008), but similar specificities at both assessments. When compared to ACR 1997, a EULAR/ACR total score ≥ 13, resulted in no differences in sensitivity and specificity at both observation periods. Conclusions: In this cSLE population, SLICC criteria better scored at first visit and 1-year-follow-up. The adoption of a EULAR/ACR total score ≥ 13 in this study, against the initially proposed ≥10 score, was most appropriate to classify cSLE. Further studies are necessary to address if SLICC criteria might allow fulfillment of cSLE classification earlier in disease course and may be more inclusive of cSLE subjects for clinical studies.


Subject(s)
Animals , Humans , Brain/metabolism , Pharmaceutical Preparations/metabolism , Blood-Brain Barrier/metabolism , Tissue Distribution/physiology , Models, Theoretical , Arachnoid/drug effects , Arachnoid/metabolism , Biological Transport/drug effects , Biological Transport/physiology , Brain/drug effects , Pharmaceutical Preparations/administration & dosage , Blood-Brain Barrier/drug effects , Tissue Distribution/drug effects , Extracellular Fluid/drug effects , Extracellular Fluid/metabolism
20.
Braz. j. med. biol. res ; 52(8): e8596, 2019. tab, graf
Article in English | LILACS | ID: biblio-1011601

ABSTRACT

The peritoneal equilibration test (PET) is the most widespread method for assessing water and solute transport across the peritoneal membrane. This study compared three methods: traditional PET (t-PET), mini-PET, and modified PET (mod-PET). Non-diabetic adults (n=21) who had been on peritoneal dialysis (PD) for at least three months underwent t-PET (glucose 2.5%-4 h), mini-PET (glucose 3.86%-1 h), and mod-PET (glucose 3.86%-4 h) to determine dialysate-to-plasma concentration ratio (D/P) for creatinine and dialysate-to-baseline dialysate concentration ratio (D/D0) for glucose. Agreement between methods regarding D/P creatinine and D/D0 glucose was assessed using analysis of variance (ANOVA), Pearson's correlation coefficient, and Bland-Altman analysis. D/P creatinine differed between t-PET and mini-PET (P<0.001) and between mod-PET and mini-PET (P<0.01) but not between t-PET and mod-PET (P=0.746). The correlation of D/P creatinine with t-PET vs mod-PET was significant (r=0.387, P=0.009) but not that of t-PET vs mini-PET (r=0.088, P=0.241). Estimated bias was −0.029 (P=0.201) between t-PET and mod-PET, and 0.206 (P<0.001) between t-PET and mini-PET. D/D0 glucose differed between t-PET and mod-PET (P=0.003) and between mod-PET and mini-PET (P=0.002) but not between t-PET and mini-PET (P=0.885). The correlations of D/D0 glucose in t-PET vs mod-PET (r=−0.017, P=0.421) or t-PET vs mini-PET (r=0.152, P=0.609) were not significant. Estimated bias was 0.122 (P=0.026) between t-PET and mod-PET, and 0.122 (P=0.026) between t-PET and mini-PET. The significant correlation of D/P creatinine between t-PET and mod-PET suggested that the latter is a good alternative to t-PET. There was no such correlation between t-PET and mini-PET.


Subject(s)
Humans , Male , Female , Middle Aged , Peritoneal Dialysis/methods , Kidney Failure, Chronic/therapy , Peritoneum/metabolism , Biological Transport , Creatinine/blood , Glucose/analysis , Kidney Failure, Chronic/blood
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