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1.
Environ Res ; 249: 118222, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38272290

RESUMO

BACKGROUND: Pesticide exposure may affect young children's neurodevelopment, but only few cohort studies have addressed possible effects of non-organophosphate pesticides. OBJECTIVE: We evaluated associations between prenatal current-use pesticide exposure and neurodevelopmental outcomes among 1-year-old children from the Infants' Environmental Health (ISA) birth cohort. METHODS: To determine prenatal pesticide exposure, we measured biomarkers of pyrimethanil, chlorpyrifos, synthetic pyrethroids, and 2,4-D in urine samples among 355 women, 1-3 times during pregnancy. One-year post-partum, we evaluated children's neurodevelopment with the Bayley Scales of Infant and Toddler Development 3rd edition (BSID-III). We assessed associations between exposures and neurodevelopmental outcomes (composite and z-scores) using single-chemical linear regression models adjusted for possible confounders (maternal education, parity, sex, gestational age at birth, child age, HOME-score, location of assessment, biomarkers of mancozeb), and studied effect-modification by sex. We evaluated non-linear associations of multiple pesticide exposures with Bayesian kernel machine regression (BKMR). RESULTS: We found higher prenatal urinary 2,4-D concentrations were associated with lower language (ßper ten-fold increase = -2.0, 95 % confidence interval (CI) = -3.5, -0.5) and motor (ßper ten-fold increase = -2.2, 95 %CI = -4.2, -0.1) composite scores among all children. Also, higher chlorpyrifos exposure [measured as urinary 3,5,6-trichloro-2-pyridinol (TCPy)] was associated with lower cognitive composite scores (ßper ten-fold increase = -1.9, 95 %CI = -4.7, 0.8), and lower motor composite scores among boys (ßper ten-fold increase = -3.8, 95 % CI = -7.7, 0.1) but not girls (ßper ten-fold increase = 2.3, 95 %CI = -1.6, 6.3, pINT = 0.11). Finally, higher pyrimethanil was associated with lower language abilities among girls, but not boys. Pyrethroid metabolite concentrations did not explain variability in BSID-III composite scores. Associations were similar for BSID-III z-scores, and we found no evidence for non-linear associations or mixture effects. DISCUSSION: Prenatal exposure to common-use pesticides may affect children's neurodevelopment at 1-year of age, some effects may be sex-specific.


Assuntos
Desenvolvimento Infantil , Praguicidas , Efeitos Tardios da Exposição Pré-Natal , Humanos , Feminino , Gravidez , Lactente , Praguicidas/urina , Praguicidas/toxicidade , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/epidemiologia , Masculino , Desenvolvimento Infantil/efeitos dos fármacos , Costa Rica , Exposição Materna/efeitos adversos , Coorte de Nascimento , Poluentes Ambientais/urina , Adulto , Estudos de Coortes , Adulto Jovem
2.
Plant Sci ; 287: 110198, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31481193

RESUMO

Aiming to counteract B deficiency impacts, plants have developed different strategies in order to reach an optimal growth in soils with limited B availability. These include B transport mechanisms that involves a facilitated transport, via channel proteins, and a high-affinity active transport driven by borate transporters. The AtNIP5;1 channel protein is a member of Major Intrinsic Protein family which facilitates B influx into the roots under low B supply. In order to explore the phytohormone-dependent regulation of AtNIP5;1, the effects of abscisic acid (ABA), ethylene, auxins and cytokinins on the activity of AtNIP5;1 promoter were evaluated using the reporter line pNIP5;1-GUS. The results show that ABA treatment increased pAtNIP5;1 activity. Besides, a larger B uptake was found following ABA treatment under B deficiency suggesting a role of ABA inducing B uptake. The ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC) caused an induction of AtNIP5;1 expression although did not correlate with higher B concentrations nor with an improvement in root growth. On the contrary, auxins and cytokinins caused slight changes in pAtNIP5;1 induction. Altogether, these results show a regulatory role of phytohormones in AtNIP5;1 promoter what may affect B transport. The herein provided information may contribute to better understand the regulation of B transport in plants towards minimizing B deficiency impacts on agriculture.


Assuntos
Aquaporinas/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Boro/metabolismo , Regulação da Expressão Gênica de Plantas , Reguladores de Crescimento de Plantas/metabolismo , Ácido Abscísico/metabolismo , Aquaporinas/genética , Arabidopsis/citologia , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Transporte Biológico , Citocininas/metabolismo , Etilenos/metabolismo , Genes Reporter , Ácidos Indolacéticos/metabolismo , Raízes de Plantas/citologia , Raízes de Plantas/genética , Raízes de Plantas/metabolismo
3.
Leukemia ; 31(7): 1659, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28386122

RESUMO

This corrects the article DOI: 10.1038/leu.2016.276.

5.
Neotrop Entomol ; 45(3): 300-9, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26874954

RESUMO

The mite Raoiella indica Hirst was recently introduced into America, where it has shown amazing ability to disseminate and broaden its range of hosts. An experiment was conducted in Cancún, Mexico, to determine infestation levels of this mite on plants recorded as hosts: coconut palm (Cocos nucifera) of cultivars Pacific Tall and Malayan Dwarf, oil palm (Elaeis guineensis) hybrids Deli x Ghana and Deli x Nigeria, Dwarf Giant banana (Musa acuminata, AAA subgroup Cavendish), Horn plantain (M. acuminata x Musa balbisiana, AAB subgroup Plantain), lobster claw (Heliconia bihai), and red ginger (Alpinia purpurata). Nursery plants of these host species or cultivars were artificially infested with R. indica in February 2011. In the four replications of 10 plants, each plant was infested with 200 R. indica specimens, and the numbers of infesting mites were recorded for 6 months. A maximum of 18,000 specimens per plant were observed on coconut Pacific Tall and Malayan Dwarf, followed by lobster claw, with a maximum of 1000 specimens per plant. Infestations were minimal for the remaining plants. Mite numbers on all plants declined naturally during the rainy season. All plant materials sustained overlapping mite generations, indicating that they are true hosts. Complementarily, infestation level was determined in backyard bananas and plantains. Correlations of infestation with plant height, distance from coconuts, and exposure to direct sunlight were estimated. Both bananas and plantains were infested by R. indica even when situated far from infested coconut palms. A Spearman correlation was found between infestation and plant height, although it was significant only for Silk plantain.


Assuntos
Cocos , Ácaros , Animais , Arecaceae , México , Musa , Densidade Demográfica
6.
Med. cután. ibero-lat.-am ; 41(5): 236-238, sept.-oct. 2013. ilus
Artigo em Espanhol | IBECS | ID: ibc-130936

RESUMO

La paraqueratosis granular es una dermatosis benigna, descrita desde 1991, de probable etiología reaccional, asociada a el uso de antitraspirantes y aoclusión local. Se presenta como pápulas hiperqueratósicas y eritematosas que confluyen formando placas de aspecto reticulado. Predomina en mujeres de mediana edad, afecta los pliegues, particularmente axilares. Presentamos el caso de un niño de 7 meses de edad con paraqueratosis granularinguinal, con respuesta favorable al manejo instaurado (AU)


Granular parakeratosis is a benign dermatosis, described since 1991, related to reactions associated with the use of antiperspirants and local occlusion. It presents as erythematous hyperkeratotic papules and plaques that come together forming a reticulated patern. This condition is more frequent in middle-aged women, affects the folds and particularly the arm. We present a 7-month-old boy with granular parakeratosis inguinal, with a good response to the treatment (AU)


Assuntos
Humanos , Masculino , Lactente , Paraceratose/diagnóstico , Granuloma Inguinal/diagnóstico , Antiperspirantes/efeitos adversos , Diagnóstico Diferencial , Dermatite de Contato/diagnóstico
7.
Nefrología (Madr.) ; 31(1): 97-106, ene.-feb. 2011. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-104678

RESUMO

Introducción: Actualmente se reconoce el efecto de distintas variables clínicas y sociodemográficas en la calidad de vida relacionada con la salud (CVRS) de los pacientes en diálisis peritoneal (DP), pero la influencia de los factores psicológicos no ha sido suficientemente explorada. El objetivo de este estudio es identificar los predictores psicológicos de la CVRS en pacientes en DP. Método: Participaron 53 pacientes en tratamiento en DP (49,54 ± 17,03 años, 54,7% mujeres) enlos que se evaluó su CVRS mediante el Kidney Disease Quality of Life Short Form y se recogió información de variables psicológicas (síntomas depresivos y ansiosos, alexitimia, locus de control relacionado con la salud y estrategias de afrontamiento), así como de variables sociodemográficas y clínicas. Resultados: Los pacientes en DP presentaron peor CVRS que la población general, particularmente en las dimensiones físicas. La comorbilidad, el número de visitas a urgencias, las hospitalizaciones previas, la albúmina, y el tratamiento previo en HD mostraron un efecto negativo en algunas dimensiones de la CVRS, pero los síntomas depresivos, la alexitimia y particularmente los síntomas ansiosos fueron los principales determinantes de la variabilidad en la CVRS de los pacientes en DP. No se encontraron relaciones significativas entre la CVRS y el locus de control o las estrategias de afrontamiento. Conclusiones: En los pacientes en DP, la ansiedad, la depresión y la alexitimia son importantes determinantes de la CVRS, por lo que deberían ser consideradas tanto en la evaluación como en el tratamiento de esta población de enfermos (AU)


Introduction: It is currently recognized the impact of different clinical and sociodemographics variables on the health related quality of life (HRQL) of patients undergoing peritoneal dialysis (DP), albeit the influence of psychological variable has not been thoroughly studied. The objective of this study is to identify the psychological predictors of HRQL in patients under DP. Method: 53 patients on DP participated in the study (49.54 ± 17.03 years, 54.7% women) in whom HRQL was evaluated by the Kidney Disease Quality of Life Short Form and it was obtained information related with psychological variables (depressive and anxious symptoms ,alexithymia, health-related locus of control and coping strategies) besides socio-demographical and clinical variables. Results: Patients on DP presented a worse HRQL than general population, particularly in the physical dimension. The comorbility, the number of visits to urgency department, previous hospital admissions, serum albumin and previous treatment with hemodialysis showed a negative impact on several dimensions of HRQL, but depressive symptoms, alexithymia and particularly anxious symptoms were the maindeterminants of the variability of HRQL in DP patients. We did not obtain a significant relationship between HRQL andthe locus of control or the coping strategies. Conclusions: Among patients undergoing DP, anxiety, depression and alexithymia are important determinants of HRQL and they should be considered both in the evaluation and the treatment of this population of patients (AU)


Assuntos
Humanos , Psicometria/instrumentação , Insuficiência Renal Crônica/psicologia , Diálise Peritoneal/psicologia , Qualidade de Vida , Ansiedade/epidemiologia , Depressão/epidemiologia , Sintomas Afetivos/epidemiologia , Região de Controle de Locus Gênico , Resiliência Psicológica
8.
Nefrologia ; 31(1): 97-106, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21270920

RESUMO

INTRODUCTION: It is currently recognized the impact of different clinical and sociodemographics variables on the health-related quality of life (HRQL) of patients undergoing peritoneal dialysis (DP), albeit the influence of psychological variable has not been thoroughly studied. The objective of this study is to identify the psychological predictors of HRQL in patients under DP. METHOD: 53 patients on DP participated in the study (49.54 ± 17.03 years, 54.7% women) in whom HRQL was evaluated by the Kidney Disease Quality of Life Short Form and it was obtained information related with psychological variables (depressive and anxious symptoms , alexithymia, health-related locus of control and coping strategies) besides socio-demographical and clinical variables. RESULTS: Patients on DP presented a worse HRQL than general population, particularly in the physical dimension. The comorbility, the number of visits to urgency department, previous hospital admissions, serum albumin and previous treatment with hemodialysis showed a negative impact on several dimensions of HRQL, but depressive symptoms, alexithymia and particularly anxious symptoms were the main determinants of the variability of HRQL in DP patients. We did not obtain a significant relationship between HRQL and the locus of control or the coping strategies. CONCLUSIONS: Among patients undergoing DP, anxiety, depression and alexithymia are important determinants of HRQL and they should be considered both in the evaluation and the treatment of this population of patients.


Assuntos
Falência Renal Crônica/psicologia , Pacientes Ambulatoriais/psicologia , Diálise Peritoneal/psicologia , Qualidade de Vida , Adaptação Psicológica , Adulto , Sintomas Afetivos/epidemiologia , Ansiedade/epidemiologia , Comorbidade , Estudos Transversais , Depressão/epidemiologia , Serviço Hospitalar de Emergência/estatística & dados numéricos , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Controle Interno-Externo , Falência Renal Crônica/sangue , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Albumina Sérica/análise , Inquéritos e Questionários
9.
Cir. plást. ibero-latinoam ; 35(3): 243-248, jul.-sept. 2009. ilus
Artigo em Espanhol | IBECS | ID: ibc-80222

RESUMO

Presentamos el caso de un paciente de 2 años de edad, conocido en su pueblo, como “el niño tortuga (testudines)”debido a la gran similitud con dicho reptil. Desdese nacimiento presentó nevus melanocítico gigante localizado en región torácica posterior, región lumbosacra y lesiones satélites en extremidades y abdomen, de 50 por40cm de diámetro y color café oscuro; la piel en las zonas afectadas es gruesa con grandes surcos de aspecto corrugado (cerebriforme).El nombre dado al niño se basa en la similitud de sus lesiones con la morfología de una tortuga, ya que el caparazón cubre la zona superior, inferior y lateral del cuerpo de este animal, de la misma forma que el nevus gigante lo hacía en el caso de nuestro paciente. Este caparazón está formado por placas óseas revestidas de placas corneas, que se asemejan a los surcos de aspecto corrugado que conforman el nevus melanocítico gigante. Los estudios clínicos practicados revelaron compromiso cardiovascular, hepático y esplénico, así como una desfavorable evolución y pronostico del cuadro clínico, por lo que esta patología, específicamente para este niño de acuerdo a la junta Médico-Quirúrgica y valoraciones, fue considerada inoperable (AU)


We present the case of a 2 years-old patient, known in his town as “turtle boy”(testudines) due to his great simility with this reptile because of his giant congenital melanocytic nevus, located in the posterior and lateral aspect of the chest and in smaller proportion in abdomen and extremities, of 50 by 40cm and dark brown colour. The skin in this zone is thick with great furrows and corrugated aspect. He was called “turtle boy” based on the morphology of the turtle, its shell covers the superior, inferior and lateral zone like in our patient’s case. It is formed bygone layers covered by cornea layers, which resemble the furrows and corrugated aspect of the giant congenital melanocytic nevus. Medical investigation reveals association with cardiovascular, hepatic and splenic compromise. According to the Clinical and Surgical Committee evaluation was inoperable (AU)


Assuntos
Humanos , Masculino , Pré-Escolar , Nevo/congênito , Índice de Gravidade de Doença
10.
Mol Plant Microbe Interact ; 14(5): 663-70, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11332730

RESUMO

Symbiosome development was studied in pea root nodules from plants growing in the absence of boron (B). Rhizobia released into the host cells of nodules from B-deficient plants developed to abnormal endophytic forms with an altered electrophoretic lipopolysaccharide pattern. Immunostaining after sodium dodecyl sulfate-polyacrylamide gel electrophoresis and electroblotting of nodule homogenates with antibodies that recognize glycoprotein components showed that two previously described lectin-like glycoproteins (PsNLEC-1A and PsNLEC-1B) did not harbor the carbohydrate epitope normally recognized by specific monoclonal antibodies. Material derived from B-deficient nodules, however, still contained three antigenic isoforms with similar electrophoretic mobilities to PsNLEC-1 isoforms A, B, and C. These could be detected following immunoblotting and immunostaining with a specific antiserum originating from the purified PsNLEC protein that had been heterologously expressed in Escherichia coli. Immunogold localization of PsNLEC-1 sugar epitopes in B-deficient nodules showed that they were associated mostly with cytoplasmic vesicles rather than normal localization in the symbiosome compartment of mature infected cells. These results suggest that a modification of the glycosyl-moieties of PsNLEC-1 and an alteration of vesicle targeting occur during the development of pea nodules in the absence of B, and that these changes are associated with the development of aberrant nonfunctional symbiosomes.


Assuntos
Boro/deficiência , Glicoproteínas/metabolismo , Pisum sativum/fisiologia , Proteínas de Plantas/metabolismo , Rhizobium leguminosarum/fisiologia , Animais , Anticorpos Monoclonais , Glicoproteínas/análise , Glicoproteínas/química , Glicosilação , Immunoblotting , Microscopia Eletrônica , Pisum sativum/microbiologia , Proteínas de Plantas/análise , Proteínas de Plantas/química , Raízes de Plantas/microbiologia , Raízes de Plantas/fisiologia , Raízes de Plantas/ultraestrutura , Ratos , Rhizobium leguminosarum/isolamento & purificação , Rhizobium leguminosarum/patogenicidade
11.
Arch Physiol Biochem ; 107(4): 323-33, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10779828

RESUMO

Implication of serum atrial natriuretic peptide (ANP) and endothelin-1 (ET1) in the central nervous system (CNS)-induced natriuresis and hypertension respectively, was investigated in healthy and cirrhotic rats. Both healthy and nonascitic CCl(4)-induced cirrhotic rats under pentobarbital anesthesia received either normotonic (140 mmol/L) or hypertonic (320 mmol/L) NaCl artificial cerebrospinal fluid into the CNS lateral ventricle at a rate of 8.3 microl/min for 120 min. A sham operated group, but not centrally infused, served as matched control. Hypertonic NaCl solution significantly increased mean arterial pressure (MAP) similarly in both healthy (n = 5) ((MAP: 16 mm Hg, 13%) and cirrhotic rats (n = 6) ((MAP: 20 mm Hg, 15%) (ANOVA, p <.001) although the latter showed a slower increment. Under hypertonic NaCl infusion, natriuresis was also significantly increased in a similar manner in both healthy (U (Na) V: baseline: 0.38 +/- 0.22 micromol/min x 100 g; experiment: 2.36 +/- 0.90 micromol/min x 100 g; mean +/- SD) and cirrhotic rats (0.69 +/- 0.48 vs. 3.16 +/- 0.87; p <.001). By contrast, central hypertonic NaCl solutions did not show a significant modification of serum ANP in neither healthy (62 +/- 18 fmol/ml vs. 51 +/- 17 fmol/ml) nor cirrhotic rats (126 +/- 61 vs. 115 +/- 30). Likewise, ET-1 was not significantly modified under central hypertonic NaCl infusion in neither healthy (352 +/- 46 pg/ml vs. 344 +/- 39 pg/ml) nor cirrhotic rats (287 +/- 58 vs. 277 +/- 61). Despite no modification in serum ANP, there was a significant increment in urinary excretion of cGMP under central hypertonic NaCl infusions in bo th healthy (6.8 +/- 4.1 pmol/min x 100 g vs. 13.0 +/- 6.5 pmol/min x 100 g; p <.05) and cirrhotic rats (8.6 +/- 1.7 vs. 11.1 +/- 1.3; p <.05). Our data indicate the preservation of the mechanisms of central natriuresis in a model of non-ascitic CCl(4 )-induced cirrhosis in rats. An increment in urinary cGMP could potentially be implicated in the natriuretic response obtained by intracerebroventricular hypertonic NaCl stimulus in both healthy and cirrhotic rats. The lack of modification of serum ANP and ET-1 does not appear to support a systemic implication of these peptides in the natriuretic and hypertensive responses respectively induced by this manoeuvre.


Assuntos
Encéfalo/metabolismo , GMP Cíclico/metabolismo , Fibrose/metabolismo , Solução Salina Hipertônica/metabolismo , Cloreto de Sódio/metabolismo , Animais , Fator Natriurético Atrial/sangue , Pressão Sanguínea/efeitos dos fármacos , Tetracloreto de Carbono , GMP Cíclico/urina , Endotelina-1/sangue , Masculino , Ratos , Ratos Wistar , Solução Salina Hipertônica/administração & dosagem , Sódio/urina , Cloreto de Sódio/administração & dosagem , Fatores de Tempo
12.
Plant Physiol ; 110(4): 1249-1256, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12226256

RESUMO

Boron (B) is an essential micronutrient for the development of nitrogen-fixing root nodules in pea (Pisum sativum). By using monoclonal antibodies that recognize specific glycoconjugate components implicated in legume root-nodule development, we investigated the effects of low B on the formation of infection threads and the colonization of pea nodules by Rhizobium leguminosarum bv viciae. In B-deficient nodules the proportion of infected host cells was much lower than in nodules from plants supplied with normal quantities of B. Moreover, the host cells often developed enlarged and abnormally shaped infection threads that frequently burst, releasing bacteria into damaged host cells. There was also an over-production of plant matrix material in which the rhizobial cells were embedded during their progression through the infection thread. Furthermore, in a series of in vitro binding studies, we demonstrated that the presence of B can change the affinity with which the bacterial cell surface interacts with the peribacteroid membrane glycocalyx relative to its interaction with intercellular plant matrix glycoprotein. From these observations we suggest that B plays an important role in mediating cell-surface interactions that lead to endocytosis of rhizobia by host cells and hence to the correct establishment of the symbiosis between pea and Rhizobium.

14.
Appl Environ Microbiol ; 61(10): 3701-4, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16535151

RESUMO

A halotolerant strain of Rhizobium meliloti was isolated from nodules of a Melilotus plant growing in a salt marsh in Donana National Park (southwest Spain). This strain, EFB1, is able to grow at NaCl concentrations of up to 500 mM, and no effect on growth is produced by 300 mM NaCl. EFB1 showed alterations on its lipopolysaccharide (LPS) structure that can be related to salt stress: (i) silver-stained electrophoretic profiles showed a different mobility that was dependent on ionic stress but not on osmotic pressure, and (ii) a monoclonal antibody, JIM 40, recognized changes in LPS that were dependent on osmotic stress. Both modifications on LPS may form part of the adaptive mechanism of this bacterium for saline environments.

15.
Biochem Soc Symp ; 60: 61-73, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7639793

RESUMO

Many classes of bacterial and plant glycoconjugate have been shown to be involved in establishing the Rhizobium root nodule symbiosis with peas (Pisum sativum). It was demonstrated, using techniques of molecular genetics, that a group of Rhizobium nodulation genes (nod genes) co-operate to synthesize a lipo-oligosaccharide signal molecule that specifically initiates nodule development on legume hosts. An additional gene function, encoded by nodX, has been found to extend the host range of Rhizobium leguminosarum bv. viciae to include nodulation of a pea mutant, cultivar Afghanistan; the nodX gene product specifies the addition of an acetyl group to the terminal N-acetylglucosamine residue at the reducing end of the pentasaccharide core of this signal molecule. Several other classes of bacterial glycoconjugate have also been shown by genetic analysis to be essential for normal nodule development and function: these include a capsular extracellular polysaccharide; lipopolysaccharide in the outer membrane; and cyclic glucans present in the periplasmic space. Potential functions for these glycoconjugates are discussed in the context of tissue and cell invasion by Rhizobium. Some plant components involved in symbiotic interactions have been identified by the analysis of nodule-specific gene expression (early nodulins). Several of the cDNA clones encoding these early nodulins specify proline-rich proteins that presumably correspond to cell wall glycoproteins or membrane arabinogalactan proteins. Other plant glycoconjugates have been identified using monoclonal antibodies as probes. A plant glycoprotein present in intercellular spaces has been identified as a component of the luminal matrix of infection threads. Because it attaches to the surface of bacteria and is itself susceptible to oxidative cross-linking, this glycoprotein may be involved in limiting the progress of microbial infections. Endocytosis of bacteria into the plant cytoplasm is apparently driven by direct interactions between the bacterial surface and the plasma membrane that is exposed within an unwalled infection droplet; glycoprotein and glycolipid components of the plant membrane glycocalyx have been defined using monoclonal antibodies. Differentiation of endosymbiotic bacteroids is preceded by differentiation of the plant-derived peribacteroid membrane which encloses the symbiosome compartment. Using a monoclonal antibody that identifies a group of plant membrane-associated, inositol-containing glycolipids, we have identified a very early marker for the differentiation of peribacteroid membrane from plasma membrane.


Assuntos
Fabaceae/metabolismo , Glicoconjugados/metabolismo , Plantas Medicinais , Rhizobium/metabolismo , Sequência de Carboidratos , Membrana Celular/metabolismo , Fabaceae/genética , Fabaceae/microbiologia , Dados de Sequência Molecular , Simbiose
16.
Plant Physiol ; 104(1): 85-90, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12232064

RESUMO

The effect of boron deficiency on symbiotic nitrogen fixation in pea (Pisum sativum) was examined. The absence of boron in the culture medium resulted in a decrease of the number of nodules and an alteration of nodule development leading to an inhibition of nitrogenase activity. Examination of boron-deficient nodules showed dramatic changes in cell walls and in both peribacteroid and infection thread membranes, suggesting a role for boron in the stability of these structures. These results indicate that boron is a requirement for normal nodule development and functionality.

19.
Artigo em Espanhol | PAHO | ID: pah-9171

RESUMO

En los países en desarrollo hace falta un instrumento empírico sencillo para identificar a embarazadas en alto riesgo de dar a luz un hijo de bajo peso. Tal instrumento ayudaría a reducir la incidencia de bajo peso al nacer, ya que permitiría brindar a estas madres cuidados prenatales apropiados. El propósito del presente estudio fue crear un instrumento de este tipo a partir de datos obtenidos antes de la 26a. semana de gestación en una población compuesta de 17 135 embarazadas de la Ciudad de Guatemala. El instrumento al parecer, podría servir para detectar el riesgo de bajo peso al nacer en las poblaciones urbanas de otros países en desarrollo


Assuntos
Recém-Nascido de Baixo Peso , Cuidado Pré-Natal , Medição de Risco , Fatores Socioeconômicos , População Urbana , América Latina , Guatemala
20.
Bull Pan Am Health Organ ; 25(2): 139-51, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1893239

RESUMO

A simple, empirically derived instrument is needed in developing countries to identify mothers at risk of delivering low birth weight (LBW) infants, in order to help reduce the incidence of LBW deliveries and provide mothers at high risk with appropriate health care. The study reported here was devoted to developing an instrument of this kind using data obtained before the twenty-sixth week of gestation from an urban study population of 17,135 Guatemalan women. It appears that this instrument could be appropriately applied to urban populations in other developing countries.


Assuntos
Recém-Nascido de Baixo Peso , Adolescente , Adulto , Análise de Variância , Países em Desenvolvimento , Feminino , Guatemala/epidemiologia , Humanos , Recém-Nascido , Modelos Logísticos , Razão de Chances , Gravidez , Diagnóstico Pré-Natal/métodos , Fatores de Risco , Saúde da População Urbana
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