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1.
Pak J Biol Sci ; 24(9): 989-996, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34585552

RESUMEN

<b>Background and Objective:</b> Boron is one of the principal elements required for plant's growth but extreme amounts of boron are toxic to humans, animals and plants. This study aimed to utilized growth rates, dry biomass and antioxidant enzyme activities to evaluate the potential of <i>Spirodela polyrhiza</i> L., in which <i>S. polyrhiza</i> produced for 120 hrs in water containing control, 10, 20, 40 and 80 mg L<sup>1</sup> of Boron and sodium chloride (NaCl) concentrations changing from 0-50 mM. <b>Materials and Methods:</b> In this study, we have done with <i>S. polyrhiza</i>, Boron and NaCl applications were continued for 120 hrs. After 120 hrs, the plants were harvested, cleaned with pure water, frozen at fluid nitrogen and stored at -80°C until further usage for enzymes activity. To determine the amount of Boron in <i>S. polyrhiza</i>, the samples were dried at 70 and then measured with Thermo ICP-MS. <b>Results:</b> The results indicated that the Boron accumulation capacity of <i>S. polyrhiza</i> diminished with accelerating salinity. <i>Spirodela polyrhiza</i> may have utilized various mechanisms to collecting Boron in high and low salt concentrations. As a conclusion of the study, it was stated that the growth rate of <i>S. polyrhiza</i> and total chlorophyll synthesis were considerably obstructed when NaCl amounts reached 50 mM. <b>Conclusion:</b> Our results indicate that CAT, APX and SOD can serve as substantial biomarkers in Boron-rich habitats. This <i>S. polyrhiza</i> is a very beneficial exemplary plant for phytoremediation advancement of contaminated wastewater with low Boron content.


Asunto(s)
Antioxidantes/metabolismo , Boro/farmacología , Malezas/efectos de los fármacos , Cloruro de Sodio/farmacología , Antioxidantes/fisiología , Boro/efectos adversos , Cloruro de Sodio/efectos adversos
3.
Plant J ; 106(5): 1455-1467, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33772920

RESUMEN

We previously reported that ribosome stalling at AUG-stop sequences in the 5'-untranslated region plays a critical role in regulating the expression of Arabidopsis thaliana NIP5;1, which encodes a boron uptake transporter, in response to boron conditions in media. This ribosome stalling is triggered specifically by boric acid, but the mechanisms are unknown. Although upstream open reading frames (uORFs) are known in many cases to regulate translation through peptides encoded by the uORF, AUG-stop stalling does not involve any peptide synthesis. The unique feature of AUG-stops - that termination follows immediately after initiation - suggests a possible effect of boron on the translational process itself. However, the generality of AUG-stop-mediated translational regulation and the effect of boron on translation at the genome scale are not clear. Here, we conducted a ribosome profiling analysis to reveal the genome-wide regulation of translation in response to boron conditions in A. thaliana shoots. We identified hundreds of translationally regulated genes that function in various biological processes. Under high-boron conditions, transcripts with reduced translation efficiency were rich in uORFs, highlighting the importance of uORF-mediated translational regulation. We found 673 uORFs that had more frequent ribosome association. Moreover, transcripts that were translationally downregulated under high-boron conditions were rich in minimum uORFs (AUG-stops), suggesting that AUG-stops play a global role in the boron response. Metagene analysis revealed that boron increased the ribosome occupancy of stop codons, indicating that this element is involved in global translational termination processes.


Asunto(s)
Arabidopsis/genética , Boro/efectos adversos , Biosíntesis de Proteínas/efectos de los fármacos , Regiones no Traducidas 5'/genética , Arabidopsis/efectos de los fármacos , Codón/genética , Sistemas de Lectura Abierta/genética , Brotes de la Planta/efectos de los fármacos , Brotes de la Planta/genética , Ribosomas/efectos de los fármacos
4.
Bioelectrochemistry ; 129: 79-89, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31125924

RESUMEN

When implantable recording devices for brain or neural electrical activity are designed, the number of available materials for electrodes is quite limited. The material must be biocompatible with respect to ISO10993, its electrochemical properties must remain stable and the response of cells or tissues can be mitigated, especially on the glial scar. This involves electrode characterization pre- implantation and impedance spectroscopy during chronic implantation, in order to evaluate both electrode properties and performance. This study was aimed at a comparison of the long-term behavior of a nanostructured boron-doped diamond (BDD) with a nanostructured Platinum Iridium (PtIr) electrode. Firstly, a batch of cortical grids with bare and modified contacts (2 mm in diameter) was engineered for implantation. Secondly a miniature swine model was developed. This study highlighted the predominant role of electrode surface roughness on the quality of recordings. Rough PtIr contacts and BDD coated ones showed comparable behavior after three-month implantation with a slight increase of the modulus of the impedance and a tissue capsule. Nevertheless, immunohistochemistry analysis did not exhibit either a toxic or irritation reaction. With regard to biocompatibility, promising long term results are shown for both materials.


Asunto(s)
Materiales Biocompatibles/química , Boro/química , Diamante/química , Electrodos Implantados , Nanoestructuras/química , Animales , Materiales Biocompatibles/efectos adversos , Boro/efectos adversos , Encéfalo/ultraestructura , Diamante/efectos adversos , Espectroscopía Dieléctrica , Técnicas Electroquímicas , Electrodos Implantados/efectos adversos , Proteína Ácida Fibrilar de la Glía/análisis , Nanoestructuras/efectos adversos , Nanoestructuras/ultraestructura , Porcinos , Porcinos Enanos
5.
J Trace Elem Med Biol ; 53: 150-153, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30910199

RESUMEN

Boron (B) compounds are essential for plants and animals and beneficial for humans in nutritional amounts. I animals and humans increasing evidence have shown beneficial effects on B compounds on nutrition and on antioxidant status. The genotoxic effects of environmental B exposure in women living in boron-rich and boron-poor areas was examined in this study. For this purpose, the DNA damage in the lymphocytes and buccal cells of females were assessed by Comet and micronucleus (MN) assays respectively. No significant difference was observed in the DNA damage of the lymphocytes of B exposed groups of female volunteers in Comet assay. Even buccal micronucleus (MN) frequency observed in the high exposure group was significantly lower than the low exposure group (p < 0.05). The results of this study came to the same conclusions of the previous studies that boron does not induce DNA damage even under extreme exposure conditions.


Asunto(s)
Boro/administración & dosificación , Daño del ADN , Exposición a Riesgos Ambientales/análisis , Células Epiteliales/efectos de los fármacos , Linfocitos/efectos de los fármacos , Boro/efectos adversos , Boro/sangre , Exposición a Riesgos Ambientales/efectos adversos , Femenino , Humanos , Mucosa Bucal/efectos de los fármacos
6.
Chemosphere ; 213: 345-350, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30241078

RESUMEN

Recently, Boron (B) contamination of aquatic ecosystem has received considerable critical attention due to its toxic effects at high concentrations on plants as well as animals. Previous studies on toxic effects of B have not dealt with DNA damages in blood and sperm cells of Nile tilapia (Oreochromis niloticus), together with blood parameters. This study consisted of two successive experiments purposes to determine these findings, including the median-lethal concentration (LC50) of B for Nile tilapia. In the first one, at 96 h, LC50 of B for Nile tilapia was 141.42 mg L-1 B. In the second one, Nile tilapia were treated with five elevated B concentrations (1, 5, 25, 50 and 100 mg L-1 B) and hematological, serum biochemical parameters, and DNA damages of Nile tilapia in these treatments were determined comparing with the control after 14 days of exposure. Hematological parameters (red blood cell count, hematocrit, and hemoglobin) were similar to each other in all groups while serum biochemical parameters (glucose, total protein, cholesterol, alkaline phosphatase, glutamic oxaloacetic transaminase, and glutamic pyruvic transaminase) in B treatments, especially in 50 and 100 mg L-1 B groups, were found significantly higher (P < 0.05). DNA fragmentation was detected in all blood cells in ≥25 mg L-1 B treatments, while all sperm cells in 100 mg L-1 B treatments. These results demonstrated the harmful effects of B at high concentration (50 and 100 mg L-1 B) on the DNA integrity of blood and sperm cells, and also the serum biochemical parameters.


Asunto(s)
Boro/efectos adversos , Fragmentación del ADN/efectos de los fármacos , Espermatozoides/química , Tilapia/microbiología , Animales , Boro/química , Peces , Masculino
7.
Arch Toxicol ; 92(8): 2475-2485, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29947890

RESUMEN

Boric acid and sodium borates are currently classified as being toxic to reproduction under "Category 1B" with the hazard statement of "H360 FD" in the European CLP regulation. This has prompted studies on boron-mediated reprotoxic effects in male workers in boron mining areas and boric acid production plants. By contrast, studies on boron-mediated developmental effects in females are scarce. The present study was designed to fill this gap. Hundred and ninety nine females residing in Bandirma and Bigadic participated in this study investigating pregnancy outcomes. The participants constituted a study group covering blood boron from low (< 100 ng B/g blood, n = 143) to high (> 150 ng B/g blood, n = 27) concentrations. The mean blood boron concentration and the mean estimated daily boron exposure of the high exposure group was 274.58 (151.81-975.66) ng B/g blood and 24.67 (10.47-57.86) mg B/day, respectively. In spite of the high level of daily boron exposure, boron-mediated adverse effects on induced abortion, spontaneous abortion (miscarriage), stillbirth, infant death, neonatal death, early neonatal death, preterm birth, congenital anomalies, sex ratio and birth weight of newborns were not observed.


Asunto(s)
Peso al Nacer/efectos de los fármacos , Boro/sangre , Contaminación de Alimentos/análisis , Exposición Materna/efectos adversos , Resultado del Embarazo/epidemiología , Contaminantes Químicos del Agua/sangre , Boro/efectos adversos , Boro/orina , Femenino , Humanos , Recién Nacido , Modelos Lineales , Embarazo , Turquía , Contaminantes Químicos del Agua/efectos adversos , Contaminantes Químicos del Agua/orina
8.
Med Hypotheses ; 104: 63-67, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28673593

RESUMEN

The iodine deficiency disorders (IDD) include a variety of disturbances such as decreased fertility, increased perinatal and infant mortality, impaired physical and intellectual development, mental retardation, cretinism, hypothyroidism, and endemic goiter (EG). The occurrence of the latter is determined by interplay between genetic and environmental factors. The major environmental factor is iodine status that is required for normal thyroid hormone synthesis. However, other factors like intake of micronutrients and goiterogens also have a significant impact. Essential and toxic trace elements both play a significant role in thyroid physiology. We hypothesize that in terms of overexposure boron may serve as a potential goiterogen. In particular, it is proposed that boron overload may impair thyroid physiology ultimately leading to goiter formation. Certain studies provide evidential support of the hypothesis. In particular, it has been demonstrated that serum and urinary B levels are characterized by a negative association with thyroid hormone levels in exposed subjects. Single indications on the potential efficiency of B in hypothyroidism also exist. Moreover, the levels of B were found to be interrelated with thyroid volume in children environmentally exposed to boron. Experimental studies also demonstrated a significant impact of boron on thyroid structure and hormone levels. Finally, the high rate of B cumulation in thyroid may also indicate that thyroid is the target for B activity. Chemical properties of iodine and boron also provide a background for certain competition. However, it is questionable whether these interactions may occur in the biological systems. Further clinical and experimental studies are required to support the hypothesis of the involvement of boron overexposure in goiter formation. If such association will be confirmed and the potential mechanisms elucidated, it will help to regulate the incidence of hypothyroidism and goiter in endemic regions with high boron levels in soil and water.


Asunto(s)
Boro/efectos adversos , Bocio Endémico/inducido químicamente , Enfermedades de la Tiroides/inducido químicamente , Anciano , Animales , Niño , Preescolar , Perros , Ambiente , Femenino , Interacción Gen-Ambiente , Humanos , Yodo/deficiencia , Yodo/fisiología , Masculino , Modelos Teóricos , Medición de Riesgo , Suelo , Oligoelementos/efectos adversos , Agua
9.
Biomaterials ; 104: 201-12, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27467416

RESUMEN

A boron delivery system with high therapeutic efficiency and low adverse effects is crucial for a successful boron neutron capture therapy (BNCT). In this study, we developed boron cluster-containing redox nanoparticles (BNPs) via polyion complex (PIC) formation, using a newly synthesized poly(ethylene glycol)-polyanion (PEG-polyanion, possessing a (10)B-enriched boron cluster as a side chain of one of its segments) and PEG-polycation (possessing a reactive oxygen species (ROS) scavenger as a side chain of one of its segments). The BNPs exhibited high colloidal stability, selective uptake in tumor cells, specific accumulation, and long retention in tumor tissue and ROS scavenging ability. After thermal neutron irradiation, significant suppression of tumor growth was observed in the BNP-treated group, with only 5-ppm (10)B in tumor tissues, whereas at least 20-ppm (10)B is generally required for low molecular weight (LMW) (10)B agents. In addition, increased leukocyte levels were observed in the LMW (10)B agent-treated group after thermal neutron irradiation, and not in BNP-treated group, which might be attributed to its ROS scavenging ability. No visual metastasis of tumor cells to other organs was observed 1 month after irradiation in the BNP-treated group. These results suggest that BNPs are promising for enhancing the BNCT performance.


Asunto(s)
Terapia por Captura de Neutrón de Boro/métodos , Boro/administración & dosificación , Depuradores de Radicales Libres/administración & dosificación , Nanopartículas/administración & dosificación , Neoplasias Experimentales/radioterapia , Neoplasias Inducidas por Radiación/prevención & control , Especies Reactivas de Oxígeno/metabolismo , Animales , Boro/efectos adversos , Boro/química , Terapia por Captura de Neutrón de Boro/efectos adversos , Línea Celular Tumoral , Isótopos/administración & dosificación , Isótopos/efectos adversos , Masculino , Ratones , Ratones Endogámicos BALB C , Neoplasias Experimentales/patología , Neoplasias Inducidas por Radiación/etiología , Radiofármacos/administración & dosificación , Radiofármacos/efectos adversos , Radiofármacos/química , Resultado del Tratamiento
10.
PLoS One ; 11(4): e0153551, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27092938

RESUMEN

In the search of alternatives for controlling Aethina tumida Murray, we recently proposed the BAA trap which uses boric acid and an attractant which mimics the process of fermentation caused by Kodamaea ohmeri in the hive. This yeast is excreted in the feces of A. tumida causing the fermentation of pollen and honey of infested hives and releasing compounds that function as aggregation pheromones to A. tumida. Since the boron is the toxic element in boric acid, the aim of this article is to assess the amount of boron residues in honey and beeswax from hives treated with the BAA trap. For this aim, the amount of bioaccumulated boron in products of untreated hives was first determined and then compared with the amount of boron of products from hives treated with the BAA trap in two distinct climatic and soil conditions. The study was conducted in the cities of Padilla, Tamaulipas, and Valladolid, Yucatan (Mexico) from August 2014 to March 2015. The quantity of boron in honey was significantly less in Yucatan than in Tamaulipas; this agrees with the boron deficiency among Luvisol and Leptosol soils found in Yucatan compared to the Vertisol soil found in Tamaulipas. In fact, the honey from Yucatan has lower boron levels than those reported in the literature. The BAA treatment was applied for four months, results show that the BAA trap does not have any residual effect in either honey or wax; i.e., there is no significant difference in boron content before and after treatment. On the other hand, the organophosphate pesticide coumaphos was found in 100% of wax samples and in 64% of honey samples collected from Yucatan. The concentration of coumaphos in honey ranges from 0.005 to 0.040 mg/kg, which are below Maximum Residue Limit (MRL) allowed in the European Union (0.1 mg/kg) but 7.14% of samples exceeded the MRL allowed in Canada (0.02 mg/kg).


Asunto(s)
Boro/efectos adversos , Boro/química , Cumafos/efectos adversos , Cumafos/química , Miel/análisis , Ceras/análisis , Animales , Canadá , Escarabajos/efectos de los fármacos , Control de Insectos/métodos , Insecticidas/efectos adversos , Insecticidas/química , México , Feromonas/efectos adversos , Polen/efectos de los fármacos , Suelo/química , Levaduras/química
11.
Complement Ther Clin Pract ; 21(2): 79-83, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25906949

RESUMEN

BACKGROUND: Primary dysmenorrhea refers to painful menstrual cramps without pelvic pathology. The condition is highly prevalent among women and exerts negative effects on their quality of life. Considering the evidence for anti-inflammatory properties of Boron, the present study aimed to determine the effects of Boron supplementation on the severity and duration of menstrual pain in female university students. METHODS: This triple-blind randomized clinical trial study recruited 113 university students. The participants were matched for the severity and duration of dysmenorrhea and randomly allocated into the case and control groups (n = 58 and 55, respectively). The case group consumed 10 mg/day Boron from two days before the menstrual flow until its third day. The control group received placebo capsules (similar to those distributed among the cases). All subjects were asked to take the capsules for two consecutive menstrual cycles. Pain severity (measured on a visual analog scale) and duration (in hours) were measured at baseline and during the two cycles. RESULTS: The two groups had no significant differences in the severity and duration of pain at baseline. After the intervention, however, the severity and duration of pain were significantly lower in the case group than in the control group (P < 0.05). CONCLUSION: Based on our findings, Boron supplementation can reduce the severity and duration of menstrual pain through exerting anti-inflammatory effects. In order to clarify the effects of Boron on dysmenorrhea, future studies are required to measure the levels of hormones and inflammatory biomarkers.


Asunto(s)
Boro/uso terapéutico , Dismenorrea/tratamiento farmacológico , Dismenorrea/fisiopatología , Manejo del Dolor/métodos , Adulto , Boro/efectos adversos , Suplementos Dietéticos , Dismenorrea/epidemiología , Femenino , Humanos , Irán/epidemiología , Manejo del Dolor/efectos adversos , Dimensión del Dolor , Adulto Joven
12.
Proc Natl Acad Sci U S A ; 111(45): 16077-81, 2014 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-25349432

RESUMEN

The application of boron neutron capture therapy (BNCT) mediated by liposomes containing (10)B-enriched polyhedral borane and carborane derivatives for the treatment of head and neck cancer in the hamster cheek pouch oral cancer model is presented. These liposomes are composed of an equimolar ratio of cholesterol and 1,2-distearoyl-sn-glycero-3-phosphocholine, incorporating K[nido-7-CH3(CH2)15-7,8-C2B9H11] (MAC) in the bilayer membrane while encapsulating the hydrophilic species Na3[ae-B20H17NH3] (TAC) in the aqueous core. Unilamellar liposomes with a mean diameter of 83 nm were administered i.v. in hamsters. After 48 h, the boron concentration in tumors was 67 ± 16 ppm whereas the precancerous tissue contained 11 ± 6 ppm, and the tumor/normal pouch tissue boron concentration ratio was 10:1. Neutron irradiation giving a 5-Gy dose to precancerous tissue (corresponding to 21 Gy in tumor) resulted in an overall tumor response (OR) of 70% after a 4-wk posttreatment period. In contrast, the beam-only protocol gave an OR rate of only 28%. Once-repeated BNCT treatment with readministration of liposomes at an interval of 4, 6, or 8 wk resulted in OR rates of 70-88%, of which the complete response ranged from 37% to 52%. Because of the good therapeutic outcome, it was possible to extend the follow-up of BNCT treatment groups to 16 wk after the first treatment. No radiotoxicity to normal tissue was observed. A salient advantage of these liposomes was that only mild mucositis was observed in dose-limiting precancerous tissue with a sustained tumor response of 70-88%.


Asunto(s)
Terapia por Captura de Neutrón de Boro/métodos , Boro/farmacología , Neoplasias de la Boca/radioterapia , Neoplasias Experimentales/radioterapia , Animales , Boro/efectos adversos , Terapia por Captura de Neutrón de Boro/efectos adversos , Cricetinae , Ensayos de Selección de Medicamentos Antitumorales , Liposomas , Mesocricetus , Neoplasias de la Boca/patología , Neoplasias Experimentales/patología , Factores de Tiempo
13.
J Drugs Dermatol ; 13(9): 1124-32, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25226015

RESUMEN

OBJECTIVE: To assess the potential efficacy, safety, and optimal dosing concentration of tavaborole, a novel, boron-based pharmaceutical agent with broad-spectrum antifungal activity, for the treatment of onychomycosis of the toenail due to dermatophytes. METHODS: One double-blind, randomized, vehicle-controlled study (study 1) and two open-label studies (studies 2 and 3) examined the efficacy, safety, and optimal dosing concentration of tavaborole topical solution applied once daily or three times weekly for 180 days at concentrations of 1.0%, 2.5%, 5.0%, or 7.5%. Patient cohort 3 of study 2 received open-label tavaborole 5.0% once daily for 360 days. All three studies assessed day 180 treatment success, defined as complete or partial clinical evidence of clear nail growth plus negative fungal culture. RESULTS: A total of 336 patients were included in the intent-to-treat (ITT) or modified ITT populations and efficacy analyses across the 3 studies. In study 1, treatment success rates at day 180 were higher with tavaborole 2.5%, 5.0%, and 7.5% vs vehicle (27%, 26%, and 32% vs 14%, respectively; slope P=0.030). In cohort 3 of study 2, 7% of patients achieved treatment success with tavaborole 5.0% at day 360. Negative culture rates at day 180 in study 1 were numerically higher for tavaborole 2.5%, 5.0%, and 7.5% vs vehicle (slope P=0.046). Application-site reactions of general irritation, erythema, scaling, and stinging/burning were most common with tavaborole 7.5%, were generally mild to moderate, and resolved with treatment discontinuation and/or a reduction in dosing frequency. No systemic safety concerns were observed. CONCLUSION: Tavaborole solution demonstrated favorable efficacy and safety in phase 2 clinical studies. Based on these findings, tavaborole topical solution, 5% was further investigated in larger, more definitive phase 3 studies. Results from these completed phase 3 studies will provide additional evidence regarding the safety and efficacy of tavaborole in the treatment of toenail onychomycosis.


Asunto(s)
Antifúngicos/administración & dosificación , Compuestos de Boro/administración & dosificación , Boro/administración & dosificación , Compuestos Bicíclicos Heterocíclicos con Puentes/administración & dosificación , Dermatosis del Pie/tratamiento farmacológico , Onicomicosis/tratamiento farmacológico , Administración Tópica , Adolescente , Adulto , Anciano , Antifúngicos/efectos adversos , Boro/efectos adversos , Compuestos de Boro/efectos adversos , Compuestos Bicíclicos Heterocíclicos con Puentes/efectos adversos , Estudios de Cohortes , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Eritema/inducido químicamente , Femenino , Dermatosis del Pie/diagnóstico , Humanos , Masculino , Persona de Mediana Edad , Onicomicosis/diagnóstico , Resultado del Tratamiento , Adulto Joven
14.
J Trace Elem Med Biol ; 26(2-3): 165-7, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22575543

RESUMEN

Boric acid and sodium borates have been considered as being "toxic to reproduction and development", following results of animal studies with high doses. However unfavorable effects of boron exposure on reproduction and development have not been proved in epidemiological studies so far. The aim of the present study was to investigate the reproductive toxicity indicators in highly exposed workers employed in a boric acid production plant in Bandirma, Turkey. Two hundred and four workers participated in this study. The mean blood boron concentration of the high exposure group of workers was 223.89 ± 69.49 (152.82-454.02)ng/g. Unfavorable effects of boron exposure on the reproductive toxicity indicators were not observed.


Asunto(s)
Boro/análisis , Boro/efectos adversos , Boro/sangre , Ensayo Cometa , Humanos , Masculino , Exposición Profesional/análisis , Turquía , Contaminantes Químicos del Agua
15.
Plant Physiol Biochem ; 56: 56-61, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22592001

RESUMEN

Boron (B) toxicity symptoms are visible in the form of necrotic spots and may worsen the oxidative stress caused by salinity. Hence, the interactive effects of combined salinity and B toxicity stress on antioxidative activities (TAC, LUPO, SOSA, CAT, and GR) were investigated by novel luminescence assays and standard photometric procedures. Wheat plants grown under hydroponic conditions were treated with 2.5 µM H3BO3 (control), 75 mM NaCl, 200 µM H3BO3, or 75 mM NaCl + 200 µM H3BO3, and analysed 6 weeks after germination. Shoot fresh weight (FW), shoot dry weight (DW), and relative water content (RWC) were significantly reduced, whereas the antioxidative activity of all enzymes was increased under salinity compared with the control. High B application led to necrotic leaf spots but did not influence growth parameters. Following NaCl + B treatment, shoot DW, RWC, SOSA, GR, and CAT activities remained the same compared with NaCl alone, whereas the TAC and LUPO activities were increased under the combined stress compared with NaCl alone. However, shoot FW was significantly reduced under NaCl + B compared with NaCl alone, as an additive effect of combined stress. Thus, we found an adjustment of antioxidative enzyme activity to the interactive effects of NaCl and high B. The stress factor "salt" mainly produced more oxidative stress than that of the factor "high B". Furthermore, addition of higher B in the presence of NaCl increases TAC and LUPO demonstrating that increased LUPO activity is an important physiological response in wheat plants against multiple stresses.


Asunto(s)
Antioxidantes/metabolismo , Boro/efectos adversos , Estrés Oxidativo , Peroxidasas/metabolismo , Hojas de la Planta/efectos de los fármacos , Cloruro de Sodio/efectos adversos , Triticum/efectos de los fármacos , Biomasa , Enzimas/metabolismo , Germinación , Hidroponía , Enfermedades de las Plantas , Hojas de la Planta/metabolismo , Proteínas de Plantas/metabolismo , Brotes de la Planta/crecimiento & desarrollo , Brotes de la Planta/metabolismo , Triticum/crecimiento & desarrollo , Triticum/metabolismo , Agua/metabolismo
16.
PLoS One ; 6(11): e27772, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22114689

RESUMEN

Boron is an essential micronutrient for plants, and it is beneficial for animals. However, at high concentrations boron is toxic to cells although the mechanism of this toxicity is not known. Atr1 has recently been identified as a boron efflux pump whose expression is upregulated in response to boron treatment. Here, we found that the expression of ATR1 is associated with expression of genes involved in amino acid biosynthesis. These mechanisms are strictly controlled by the transcription factor Gcn4 in response to boron treatment. Further analyses have shown that boron impaired protein synthesis by promoting phosphorylation of eIF2α in a Gcn2 kinase dependent manner. The uncharged tRNA binding domain (HisRS) of Gcn2 is necessary for the phosphorylation of eIF2α in the presence of boron. We postulate that boron exerts its toxic effect through activation of the general amino acid control system and inhibition of protein synthesis. Since the general amino acid control pathway is conserved among eukaryotes, this mechanism of boron toxicity may be of general importance.


Asunto(s)
Aminoácidos/metabolismo , Boro/efectos adversos , Biosíntesis de Proteínas/efectos de los fármacos , Saccharomyces cerevisiae/efectos de los fármacos , Aminoacilación/efectos de los fármacos , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/genética , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/metabolismo , Biomarcadores/metabolismo , Western Blotting , Perfilación de la Expresión Génica , Proteínas de Transporte de Membrana/genética , Proteínas de Transporte de Membrana/metabolismo , Análisis de Secuencia por Matrices de Oligonucleótidos , Fosforilación/efectos de los fármacos , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , ARN Mensajero/genética , ARN de Transferencia , Reacción en Cadena en Tiempo Real de la Polimerasa , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , eIF-2 Quinasa/genética , eIF-2 Quinasa/metabolismo
17.
Biol Trace Elem Res ; 143(2): 738-50, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21170602

RESUMEN

The possible changes in semen quality were studied in men living in a boron mining area. The subjects in the boron group had exposure to boron at an average level of 6.5 mg/day, as determined by urinary analysis. The results obtained by the boron group were compared to those obtained for the control group whose subjects were living in the same geographical area but away from the boron region; average exposure level was 1.4 mg/day for this group. The semen samples were analyzed according to the recommendations of the World Health Organization. Boron levels were established in the water samples obtained from various locations in the study region. In the boron mining fields where the subjects in the boron group live, water samples contained boron in the range of 1.4-6.5 mg/L, while the values were <0.01 mg/L for the water samples obtained from the region where the subjects of the control group reside. No negative effects were found in the sperm samples obtained from the subjects of the boron group.


Asunto(s)
Boro/efectos adversos , Boro/análisis , Semen/efectos de los fármacos , Adolescente , Adulto , Boro/orina , Agua Potable/efectos adversos , Agua Potable/análisis , Humanos , Masculino , Espectrometría de Masas , Semen/química , Adulto Joven
18.
Santiago de Chile; Pontificia Universidad Católica de Chile. Facultad de Medicina. Departamento de Salud Pública; dic. 2008. 111 p. ilus, tab.
Monografía en Español | MINSALCHILE | ID: biblio-1543969
19.
J Diet Suppl ; 5(1): 62-94, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-22433045

RESUMEN

OBJECTIVE: To evaluate the scientific evidence on boron including expert opinion, folkloric precedent, history, pharmacology, kinetics/dynamics, interactions, adverse effects, toxicology, and dosing. This review serves as a clinical support tool. METHODS: Electronic searches were conducted in nine databases, 20 additional journals (not indexed in common databases), and bibliographies from 50 selected secondary references. No restrictions were placed on language or quality of publications. All literature collected pertained to efficacy in humans, dosing, precautions, adverse effects, use in pregnancy/lactation, interactions, alteration of laboratory assays, and mechanisms of action. Standardized inclusion/exclusion criteria are utilized for selection. Grades were assigned using an evidence-based grading rationale. RESULTS: There was a lack of systematic study on the safety and effectiveness of boron in humans. However, based on popular use and supportive scientific data, nine indications are discussed in this review: hormone regulation, improving cognitive function, osteoarthritis, osteoporosis, vaginitis (topical), bodybuilding aid (increasing testosterone), menopausal symptoms, prevention of blood clotting (coagulation effects), and psoriasis (topical). CONCLUSION: Although studies assessing the use of boron for osteoarthritis and osteoporosis are in preliminary stages, reports are promising. There is conflicting evidence to support the use of boron in hormonal regulation and cognitive function. Future randomized controlled trials are warranted. There is fair negative evidence regarding the use of boron as an anticoagulant, a bodybuilding aid, for menopausal symptoms, or for psoriasis. Excessive use may be harmful, and caution is advised.


Asunto(s)
Boro , Oligoelementos , Coagulación Sanguínea/efectos de los fármacos , Boro/efectos adversos , Boro/farmacología , Boro/uso terapéutico , Cognición/efectos de los fármacos , Femenino , Hormonas/metabolismo , Humanos , Menopausia/efectos de los fármacos , Enfermedades Musculoesqueléticas/tratamiento farmacológico , Psoriasis/tratamiento farmacológico , Oligoelementos/efectos adversos , Oligoelementos/farmacología , Oligoelementos/uso terapéutico , Vaginitis/tratamiento farmacológico
20.
Int. j. morphol ; 25(2): 341-346, jun. 2007. ilus, tab
Artículo en Español | LILACS | ID: lil-495933

RESUMEN

Boric acid and borate are abundant in the nature and widely used in industrial, agricultural and cosmetology applications. However it is informed as toxic in a high dose. Residents of Arica-Chile with boron-rich geology deposits are regularly exposed to higher levels in drinking water in concentrations of 6. 0 and 12.0 mg/L. The objective of this study was to analyze the damage in the masculine reproductive apparatus of mouse CF1, exposed to boric acid in concentrations of 0.54; 2.0-6.0 and 12.0 mg/L, after 60 days of treatment. Male gonad segments were fixed in Bouin's solution for 6 hours and embedded in paraffin, longitudinal sections (5 mm) were processed for histology using the hematoxyline/eosin method. The results observed in treated animals indicate a significant increase in the weight, volume and size of testicles and seminal vesicles. The histological analysis of testicle shows in treated an epithelium notoriously altered with vacuohzations, scarce gonias and few spermatids. Gonias present picnoticals nuclei, suggesting apoptosis. In conclusion boron in high dose produces important cytotoxics effects, with degeneration of epithelium of seminiferous tubules, possibly inhibiting the spermiation, causing testicular hypertrophy, altering the masculine reproductive patterns and a reduction in fertility of mice CF1.


El ácido bórico y el borato son abundantes en la naturaleza y con amplio uso industrial, agrícola y cosmetológico. Sin embargo, se informa como tóxico en alta dosis. Residentes de la ciudad de Arica-Chile, están expuestos a altos niveles de boro presente en el agua potable, con concentraciones 6.0 y 12.0 mg/1. El objetivo de este estudio fue analizar el daño en el sistema reproductivo masculino del ratón CF1, expuesto a ácido bórico en concentraciones de 0.54; 2.0-6.0 y 12.0 mg/1, por un período de 60 días de tratamiento. Los segmentos masculinos de las gónadas fueron fijados en solución de Bouin por 6 horas e incluidos en parafina, secciones longitudinales (5 /aa) fueron procesadas para histología usando el método hematoxilina/eosina. Los resultados observados en animales tratados indican un aumento significativo en el peso, el volumen y el tamaño de testículos y de vesículas seminales. El análisis histológico de testículo de individuos tratados, muestra un epitelio alterado con vacuolizaciones, escasas gomas y pocas espermátidas. Gonias presentan núcleos picnóticos, sugiriendo apoptosis. En conclusión el boro en alta dosis produce efectos citotóxicos importantes, con degeneración de epitelio de túbulos seminíferos, posiblemente inhibiendo la espermiación, causando hipertrofia testicular, alterando los patrones reproductivos masculinos y una reducción en la fertilidad de los ratones CF1.


Asunto(s)
Masculino , Animales , Ratones , Atrofia/inducido químicamente , Boro/efectos adversos , Espermatogénesis , Testículo , Testículo/patología , Contaminación del Agua , Chile
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