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1.
MethodsX ; 12: 102642, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38660026

RESUMEN

The number of publications related to the implementation of nanotechnology in the construction industry, and specifically to the application of nanosilica (SiO2), has had a constant increase in recent years. Based on this, in the present work, an analysis was carried out using bibliometric techniques, with the aim at characterizing the development of specialized literature and identifying the largest areas of growth in the field, maintaining hydrophobic nanosilica as the research guideline. This analysis acquired information from the Scopus and Web of Science (WoS) databases to compare bibliometric indicators of the publications. It should be noted that, even though bibliometric analysis is useful to identify the study areas of greatest interest, to complement this work, the implementation of a method that helped in the research process to obtain the most important bibliography was required. This study implemented Methodi Ordinatio, which helped to take a new direction. Therefore, based on this method, a list of articles cataloged and ranked is obtained, which is the basis for integrating the final bibliographic portfolio. •The study applies the Methodi Ordinatio to obtain a portfolio of the most relevant articles to guide the researchers' work.•Insightful information can be obtained using VOSviewer to analyze and visualize metadata of the bibliographic portfolio.•The study demonstrates how the alpha value in the InOrdinatio formula modifies the resulting portfolio.

2.
Med Intensiva (Engl Ed) ; 47(8): 437-444, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36464582

RESUMEN

OBJECTIVE: This study aimed to investigate chlorhexidine's efficacy in preventing ventilator-associated pneumonia (VAP). DESIGN: A systematic review and meta-analysis were conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. SETTINGS: The data were obtained from Pubmed, Cochrane Library, and EMBASE. PATIENTS OR PARTICIPANTS: Only mechanically ventilated patients for at least 48h were included. INTERVENTIONS: Randomized clinical trials applying any dosage form of chlorhexidine were eligible. MAIN VARIABLES OF INTEREST: The relative risk (RR) of the VAP incidence and all-cause mortality was assessed using the random-effects model. The mean difference in days of mechanical ventilation duration and intensive care unit (ICU) length of stay were also appraised. RESULTS: Ten studies involving 1233 patients were included in the meta-analysis. The oral application of CHX reduced the incidence of VAP (RR, 0.73 [95% CI, 0.55, 0.97]) and did not show an increase in all-cause mortality (RR, 1.13 [95% CI, 0.96, 1.32]). CONCLUSIONS: CHX proved effective to prevent VAP. However, a conclusion on mortality rates could not be drawn because the quality of the evidence was very low for this outcome.


Asunto(s)
Clorhexidina , Neumonía Asociada al Ventilador , Humanos , Clorhexidina/uso terapéutico , Neumonía Asociada al Ventilador/epidemiología , Neumonía Asociada al Ventilador/prevención & control , Incidencia , Respiración Artificial/efectos adversos , Unidades de Cuidados Intensivos
3.
Infect Genet Evol ; 103: 105322, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35753623

RESUMEN

Cross-species transmission events and mixed infection of small ruminant lentiviruses (SRLVs) were studied in seven goats and two sheep from three small ruminant mixed flocks from Northeast and Southeast Brazil. Genetic and antigenic analyses with gag/env genes and ELISA multiepitope SU1/SU5 recombinant antigens were carried out, respectively. The genetic analysis of gag and env sequences showed high viral diversity in both species, MVV-like (subtype A1) and CAEV-like B1 in goats, and CAEV-like (subtype B1) in sheep, revealing SRLV interspecies transmission from sheep to goats and vice versa in Brazilian farms. Two Brazilian caprine lentiviruses were segregated in two new genetic clades based on gag analyses, which suggests a new classification into heterogenic genotype A. Furthermore, goat isolates were grouped into subtype A1 and B1 clusters. Cross-reactive antibodies were detected in goats using ELISA with a recombinant antigen carrying SU1 and SU5 immunodominant epitopes; the results showed anti-CAEV and MVV antibodies in goats and anti-CAEV antibodies in sheep. This result can be associated with the high divergence in the V4 region due to SRLV variability. All results confirm cross-species infection of SRLV in Brazilian mixed herds.


Asunto(s)
Enfermedades de las Cabras , Infecciones por Lentivirus , Enfermedades de las Ovejas , Animales , Brasil/epidemiología , Cabras , Lentivirus/genética , Infecciones por Lentivirus/veterinaria , Filogenia , Rumiantes , Ovinos
4.
Neuroscience ; 442: 286-295, 2020 08 21.
Artículo en Inglés | MEDLINE | ID: mdl-32599125

RESUMEN

During prolonged dehydration, body fluid homeostasis is challenged by extracellular fluid (ECF) hyperosmolality, which induce important functional changes in the hypothalamus, in parallel with other effector responses, such as the activation of the local renin-angiotensin system (RAS). Therefore, in the present study we investigated the role of sodium-driven ECF hyperosmolality on glial fibrillary acid protein (GFAP) immunoreactivity and protein expression, membrane capacitance, mRNA expression of RAS components and glutamate balance in cultured hypothalamic astrocytes. Our data show that hypothalamic astrocytes respond to increased hyperosmolality with a similar decrease in GFAP expression and membrane capacitance, indicative of reduced cellular area. Hyperosmolality also downregulates the transcript levels of angiotensinogen and both angiotensin-converting enzymes, whereas upregulates type 1a angiotensin II receptor mRNA. Incubation with hypertonic solution also decreases the immunoreactivity to the membrane glutamate/aspartate transporter (GLAST) as well as tritiated-aspartate uptake by astrocytes. This latter effect is completely restored to basal levels when astrocytes previously exposed to hypertonicity are incubated under isotonic conditions. Together with a direct effect on two important local signaling systems (glutamate and RAS), these synaptic rearrangements driven by astrocytes may accomplish for a coordinated increase in the excitatory drive onto the hypothalamic neurosecretory system, ultimately culminating with increased AVP release in response to hyperosmolality.


Asunto(s)
Astrocitos , Ácido Glutámico , Astrocitos/metabolismo , Células Cultivadas , Transportador 2 de Aminoácidos Excitadores/metabolismo , Proteína Ácida Fibrilar de la Glía/metabolismo , Hipotálamo/metabolismo , ARN Mensajero
5.
Ginecol Obstet Mex ; 84(4): 243-51, 2016 Apr.
Artículo en Español | MEDLINE | ID: mdl-27443100

RESUMEN

OBJECTIVE: To report of experience of intrauterine hydrostatic condom to control obstetric hemorrhage. MATERIAL AND METHOD: Descriptive, retro-prospective study. The method was use in patients who had obstetric hemorrhage and do not responded to medical management during the period from March 1st to August27, 2015 in a rural facility. RESULTS: 955 patients that had a vaginal delivery were identified, 40 (4.1%) of which needed the application of the method. The method was unsuccessful in 2 of 40 patients (5%), one requiring emergency obstetric hysterectomy and other exploratory laparotomy with conservative measures. 11 of 40 patients (2 7.5%) required at least 1-3 globular packs transfusion. None of the 38 patients (95%) who responded to the method presented endometritis in the postpartum follow up or complications associated with the use of hydrostatic condom. CONCLUSION: The use of intrauterine hydrostatic condom is an effective method to control postpartum obstetric hemorrhage secondary to uterine atony unresponsive to medical management.


Asunto(s)
Embolización Terapéutica/métodos , Hemorragia Posparto/terapia , Adolescente , Adulto , Condones , Embolización Terapéutica/instrumentación , Femenino , Humanos , Estudios Prospectivos , Estudios Retrospectivos , Útero , Adulto Joven
6.
Genet Mol Res ; 15(2)2016 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-27173186

RESUMEN

Fusarium oxysporum f. sp cubense (Foc), the causal agent of Panama disease, is responsible for economic losses in banana crops worldwide. The identification of genes that effectively act on pathogenicity and/or virulence may contribute to the development of different strategies for disease control and the production of resistant plants. The objective of the current study was to analyze the importance of SGE1 gene expression in Foc virulence through post-transcriptional silencing using a double-stranded RNA hairpin. Thirteen transformants were selected based on different morphological characteristics, and sporulation in these transformants was significantly reduced by approximately 95% (P < 0.05) compared to that of the wild-type strain. The relative SGE1 expression levels in the transformant strains were reduced by 27 to 47% compared to those in the wild-type strain. A pathogenicity analysis revealed that the transformants were able to reach the rhizomes and pseudostems of the inoculated banana plants. However, the transformants induced initial disease symptoms in the banana plants approximately 10 days later than that by the wild-type Foc, and initial disease symptoms persisted even at 45 days after inoculation. These results indicate that the SGE1 gene is directly involved in the virulence of Foc. Therefore, SGE1 may be a potential candidate for host-induced gene silencing in banana plants.


Asunto(s)
Proteínas Fúngicas/genética , Fusarium/genética , Proteínas Fúngicas/metabolismo , Fusarium/patogenicidad , Interferencia de ARN , ARN Interferente Pequeño/genética , Virulencia/genética
7.
Sci Total Environ ; 542(Pt A): 93-101, 2016 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-26519570

RESUMEN

It has been recognized that numerous synthetic compounds like Bisphenol A (BPA) and nonylphenols (NP) are present in effluents from wastewater treatment plants (WWTP) at levels of parts per billion (µg L(-1)) or even parts per trillion (ng L(-1)) with a high potential to cause endocrine disruption in the aquatic environment. Constructed wetlands (CW) are a cost-effective wastewater treatment alternative with promising performance to treat these afore mentioned compounds. This research was aimed to evaluate the efficacy of CW treatment of WWTP effluent for mitigating the effects endocrine disrupting compounds (EDCs). This research goal was accomplished by (1) quantifying the removal of BPA and NP in CWs; (2) isolating CW fungal strains and testing for laccase production; and (3) performing endocrine disruption (reproduction) bioassays using the fruit fly Drosophila melanogaster. Three pilot scale horizontal subsurface flow constructed wetlands (HSSF-CW) were operated for eight weeks: one planted with Phragmites australis; one planted with Heliconia psitacorum; and one unplanted. The Heliconia CW showed a removal efficiency of 73.3(± 19%) and 62.8(± 20.1%) for BPA and NP, respectively; while the Phragmites CW demonstrated a similar removal for BPA (70.2 ± 27%) and lower removal efficiency for NP 52.1(± 37.1%).The unplanted CW achieved 62.2 (± 33%) removal for BPA and 25.3(± 37%) removal for NP. Four of the eleven fungal strains isolated from the Heliconia-CW showed the capacity to produce laccase. Even though complete removal of EDCs was not achieved by the CWs, the bioassay confirmed a significant improvement (p < 0.05) in fly viability for all CWs, with Heliconia sp. being the most effective at mitigating adverse effects on first and second generational reproduction. This study showed that a CW planted with a native Heliconia sp. CW demonstrated a higher removal of endocrine disrupting compounds and better mitigation of reproductive disruption in the bioassay.


Asunto(s)
Compuestos de Bencidrilo/análisis , Fenoles/análisis , Eliminación de Residuos Líquidos/métodos , Aguas Residuales/química , Contaminantes Químicos del Agua/análisis , Humedales
8.
Genet Mol Res ; 14(3): 9932-8, 2015 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-26345928

RESUMEN

Endophytic microorganisms colonize plants, inhibit the growth of pathogens (by competing for nutrients and/or space), or produce antagonistic substances. Fifty-five endophytic bacteria were isolated from the leaf tissue of the FHIA 18 banana cultivar. Genetic diversity analyses were performed using the enterobacterial repetitive intergenic consensus sequence polymerase chain reaction method and BOX molecular markers. These analyses resulted in 33 and 21 polymorphic bands, respectively. The similarity data, obtained using the Dice coefficient based on the polyphasic analysis method, ranged from 22 to 100%. This indicated a high genetic diversity among the analyzed isolates. Sixty percent similarity was utilized as the cut-off criterion for the formation of operational taxonomic units (OTUs); this resulted in the identification of 32 possible OTUs, indicating a high number of potential species.


Asunto(s)
Bacterias/clasificación , Bacterias/genética , Musa/microbiología , Brasil , ADN Bacteriano , Variación Genética , Filogenia , Secuencias Repetitivas de Ácidos Nucleicos
9.
Appl Radiat Isot ; 105: 299-302, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26386504

RESUMEN

This paper aims to evaluate the feasibility of applying LiF:Mg,Ti microdosimeters as a new method of dosimetry to volumetric-modulated arc therapy (VMAT) RapidArc. The response of microdosimeters presented a maximum variation of ±3.18% and ±0.510% using optically stimulated luminescence (OSL) and thermoluminescence (TL) techniques, respectively. Although studies were conducted on LiF:Mg,Ti microdosimeters previously, the microdosimeters in this study showed precision and high potential of application in VMAT dosimetry and in the verification of treatment planning using the VMAT technique.


Asunto(s)
Radiometría/métodos , Radioterapia de Intensidad Modulada/normas , Fluoruros , Humanos , Compuestos de Litio , Luminiscencia , Magnesio , Fantasmas de Imagen , Polimetil Metacrilato , Control de Calidad , Radiometría/instrumentación , Radiometría/estadística & datos numéricos , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador , Radioterapia de Intensidad Modulada/estadística & datos numéricos , Dosimetría Termoluminiscente/instrumentación , Dosimetría Termoluminiscente/métodos , Dosimetría Termoluminiscente/estadística & datos numéricos , Titanio
10.
BJOG ; 122(12): 1586-92, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26213116

RESUMEN

OBJECTIVE: To evaluate the usefulness of serial determinations of asymmetric dimethylarginine (ADMA) and homocysteine (Hcy) concentrations during pregnancy to predict pre-eclampsia, taking into account maternal obesity and B vitamin status. DESIGN: Longitudinal study. SETTING: Two obstetric referral hospitals. SAMPLE: Two hundred and fifty-two of 411 women invited to participate in the study. METHODS: The women made monthly visits from ≤20 weeks of gestation until delivery for measurements of plasma ADMA, Hcy, and vitamins B6 , B12, and folic acid, and for the recording of clinical information. MAIN OUTCOME MEASURE: Early elevations in plasma ADMA and Hcy related to the development of pre-eclampsia. RESULTS: Of the 252 women who completed the study, 179 had no complications, 49 developed pre-eclampsia, and 24 presented with complications other than pre-eclampsia. ADMA and Hcy increased gradually throughout pregnancy in the pre-eclampsia group, independent of maternal B-vitamin status and obesity, but remained constant in women with no complications. Relative to the preceding month, ADMA and Hcy levels increased 1 month prior to the onset of pre-eclampsia: 124 ± 27 nmol (P < 0.001) and 1177 ± 278 nmol (P = 0.001), respectively, in the pre-eclampsia group. The group of women with no complications did not show any significant changes. Increases of 80 nmol ADMA and 1000 nmol Hcy at 1 month prior to the onset of pre-eclampsia demonstrated the best potential for prediction. CONCLUSIONS: Increased ADMA and Hcy levels precede clinical manifestations of pre-eclampsia. Therefore, serial determinations of their concentrations may be helpful in identifying women at risk. TWEETABLE ABSTRACT: Increased ADMA and Hcy precede clinical pre-eclampsia and may identify women at risk.


Asunto(s)
Arginina/análogos & derivados , Ácido Fólico/sangre , Homocisteína/sangre , Preeclampsia/sangre , Preeclampsia/diagnóstico , Complejo Vitamínico B/sangre , Deficiencia de Vitamina B/sangre , Adulto , Arginina/sangre , Biomarcadores/sangre , Índice de Masa Corporal , Femenino , Estudios de Seguimiento , Humanos , Estudios Longitudinales , Preeclampsia/epidemiología , Valor Predictivo de las Pruebas , Embarazo , Factores de Riesgo , Reino Unido/epidemiología , Deficiencia de Vitamina B/epidemiología
11.
Artículo en Inglés | MEDLINE | ID: mdl-25375467

RESUMEN

Motivated by studies on the recurrent properties of animal and human mobility, we introduce a path-dependent random-walk model with long-range memory for which not only the mean-square displacement (MSD) but also the propagator can be obtained exactly in the asymptotic limit. The model consists of a random walker on a lattice, which, at a constant rate, stochastically relocates at a site occupied at some earlier time. This time in the past is chosen randomly according to a memory kernel, whose temporal decay can be varied via an exponent parameter. In the weakly non-Markovian regime, memory reduces the diffusion coefficient from the bare value. When the mean backward jump in time diverges, the diffusion coefficient vanishes and a transition to an anomalous subdiffusive regime occurs. Paradoxically, at the transition, the process is an anticorrelated Lévy flight. Although in the subdiffusive regime the model exhibits some features of the continuous time random walk with infinite mean waiting time, it belongs to another universality class. If memory is very long-ranged, a second transition takes place to a regime characterized by a logarithmic growth of the MSD with time. In this case the process is asymptotically Gaussian and effectively described as a scaled Brownian motion with a diffusion coefficient decaying as 1/t.

12.
Genet Mol Res ; 13(4): 8661-70, 2014 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-25366756

RESUMEN

Endophytic microorganisms consist of fungi, bacteria, and actinomycetes that play important roles in the process of plant adaptation to the environment. Currently, the natural associations between microorganisms and plant species are being explored for a large number of biotechnological applications. In this study, 122 endophytic bacteria were isolated from 5 cultivars of Musa spp from the state of Amazonas (Brazil). Four strains were selected because they exhibited antagonistic activities against Fusarium oxysporum f. sp cubense and Colletotrichum guaranicola, with inhibitions ranging from 19 to 30% and 27 to 35%, respectively. Phylogenetic analysis of the 16S rDNA regions of these bacteria with antifungal activity showed that they are phylogenetically related to 3 different species of Bacillus - B. amyloliquefaciens, B. subtilis subsp subtilis, and B. thuringiensis.


Asunto(s)
Antibiosis , Bacillus/aislamiento & purificación , Endófitos/aislamiento & purificación , Fusarium/fisiología , Musa/microbiología , Bacillus/genética , Bacillus/fisiología , Endófitos/genética , Endófitos/fisiología , ARN Ribosómico 16S/genética
13.
Eur J Obstet Gynecol Reprod Biol ; 171(1): 67-72, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23993131

RESUMEN

OBJECTIVES: To analyze the expression of protein markers related to cell proliferation and death, as well as oestrogen and progesterone receptors in the endometrium of infertile women with hypothalamic-pituitary dysfunction treated with clomiphene citrate (CC) or recombinant follicle-stimulating hormone (rFSH), and compare them with ovulatory women. STUDY DESIGN: The study included 12 control ovulatory women and 29 anovulatory women, 19 of whom underwent ovulation induction with CC (n = 12) or rFSH (n = 5). Endometrial biopsies were obtained by Pipelle during the mid-secretory phase. Samples were stained with haematoxylin and eosin. Immunohistochemistry of proteins related to cell proliferation and cell death, as well as steroid receptors, was undertaken, and apoptosis was determined using TUNEL analysis. RESULTS: Immunohistochemical analysis of Ki67 expression showed significantly higher expression in the glandular epithelium of ovulatory women compared with the other groups. Glandular oestrogen receptor α expression was significantly lower in rFSH-treated women compared with ovulatory women. The number of apoptotic cells, Bax expression and progesterone receptor expression were similar in all groups. In contrast, Bcl-2 expression was significantly lower in the glandular epithelium of rFSH-treated women. CONCLUSIONS: In infertile women with hypothalamic-pituitary dysfunction, treatment with ovulation-inducing agents modifies the expression of proteins involved in cell proliferation and death, as well as the expression of steroid hormone receptors in the endometrium. These differences may help to explain, at the molecular level, the functionality of the endometrium during the implantation window, and may help to optimize pregnancy rates obtained with these treatments.


Asunto(s)
Clomifeno/uso terapéutico , Endometrio/metabolismo , Fármacos para la Fertilidad Femenina/uso terapéutico , Hormona Folículo Estimulante/uso terapéutico , Infertilidad Femenina/metabolismo , Adulto , Muerte Celular/fisiología , Proliferación Celular , Receptor alfa de Estrógeno/biosíntesis , Femenino , Humanos , Infertilidad Femenina/tratamiento farmacológico , Fase Luteínica/fisiología , Inducción de la Ovulación , Receptores de Progesterona/biosíntesis , Proteína X Asociada a bcl-2/biosíntesis
14.
Braz J Med Biol Res ; 46(4): 327-38, 2013 04.
Artículo en Inglés | MEDLINE | ID: mdl-23579631

RESUMEN

Several forebrain and brainstem neurochemical circuitries interact with peripheral neural and humoral signals to collaboratively maintain both the volume and osmolality of extracellular fluids. Although much progress has been made over the past decades in the understanding of complex mechanisms underlying neuroendocrine control of hydromineral homeostasis, several issues still remain to be clarified. The use of techniques such as molecular biology, neuronal tracing, electrophysiology, immunohistochemistry, and microinfusions has significantly improved our ability to identify neuronal phenotypes and their signals, including those related to neuron-glia interactions. Accordingly, neurons have been shown to produce and release a large number of chemical mediators (neurotransmitters, neurohormones and neuromodulators) into the interstitial space, which include not only classic neurotransmitters, such as acetylcholine, amines (noradrenaline, serotonin) and amino acids (glutamate, GABA), but also gaseous (nitric oxide, carbon monoxide and hydrogen sulfide) and lipid-derived (endocannabinoids) mediators. This efferent response, initiated within the neuronal environment, recruits several peripheral effectors, such as hormones (glucocorticoids, angiotensin II, estrogen), which in turn modulate central nervous system responsiveness to systemic challenges. Therefore, in this review, we shall evaluate in an integrated manner the physiological control of body fluid homeostasis from the molecular aspects to the systemic and integrated responses.


Asunto(s)
Líquidos Corporales/fisiología , Homeostasis/fisiología , Vías Nerviosas/fisiología , Neurosecreción/fisiología , Neurotransmisores/fisiología , Transducción de Señal/fisiología , Animales , Mapeo Encefálico , Humanos , Concentración Osmolar
15.
Braz. j. med. biol. res ; 46(4): 327-338, 05/abr. 2013.
Artículo en Inglés | LILACS | ID: lil-671387

RESUMEN

Several forebrain and brainstem neurochemical circuitries interact with peripheral neural and humoral signals to collaboratively maintain both the volume and osmolality of extracellular fluids. Although much progress has been made over the past decades in the understanding of complex mechanisms underlying neuroendocrine control of hydromineral homeostasis, several issues still remain to be clarified. The use of techniques such as molecular biology, neuronal tracing, electrophysiology, immunohistochemistry, and microinfusions has significantly improved our ability to identify neuronal phenotypes and their signals, including those related to neuron-glia interactions. Accordingly, neurons have been shown to produce and release a large number of chemical mediators (neurotransmitters, neurohormones and neuromodulators) into the interstitial space, which include not only classic neurotransmitters, such as acetylcholine, amines (noradrenaline, serotonin) and amino acids (glutamate, GABA), but also gaseous (nitric oxide, carbon monoxide and hydrogen sulfide) and lipid-derived (endocannabinoids) mediators. This efferent response, initiated within the neuronal environment, recruits several peripheral effectors, such as hormones (glucocorticoids, angiotensin II, estrogen), which in turn modulate central nervous system responsiveness to systemic challenges. Therefore, in this review, we shall evaluate in an integrated manner the physiological control of body fluid homeostasis from the molecular aspects to the systemic and integrated responses.


Asunto(s)
Animales , Humanos , Líquidos Corporales/fisiología , Homeostasis/fisiología , Vías Nerviosas/fisiología , Neurosecreción/fisiología , Neurotransmisores/fisiología , Transducción de Señal/fisiología , Mapeo Encefálico , Concentración Osmolar
16.
Appl Radiat Isot ; 70(7): 1360-2, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22342311

RESUMEN

This paper compares the performance of CaSO4:Dy and LiF dosimeters irradiated with a 15 MV photon beam of a clinical linear accelerator to 0.1-10 Gy in a liquid water. The dose-response curves are linear up to 5 Gy. The average TL sensitivity of CaSO4:Dy is 26 and 287 times higher than the sensitivities of LiF:Mg,Ti and microLiF:Mg,Ti, respectively. CaSO4:Dy has an intrinsic efficiency 71% and 94% higher than the intrinsic efficiencies of LiF:Mg,Ti and microLiF:Mg,Ti, respectively.


Asunto(s)
Fantasmas de Imagen , Fotones , Dosimetría Termoluminiscente/instrumentación , Sulfato de Calcio/análisis , Relación Dosis-Respuesta en la Radiación , Límite de Detección
18.
Arq. bras. med. vet. zootec ; 61(2): 306-312, abr. 2009. ilus, tab
Artículo en Inglés | LILACS | ID: lil-518707

RESUMEN

The histological changes of the liver in ewes with pregnancy toxemia were characterized. Ten ewes were fed on grass ad libitum, and another ten were starved from day 130 of pregnancy for up to four days. Liver puncture biopsies were performed at days 70, 100, 130, and 140 of pregnancy, and at day 45 in postpartum. Seric hydroxybutyrate (HB), non-esterified fatty acids (NEFA), aspartate aminotransferase, and alkaline phosphatase were dosed. Histological preparations revealed similar incidence and intensity of mild liver steatosis in both groups at day 130. Starved ewes become toxemic (as indicated by HB), and at day 140 exhibited more severe injury in a higher proportion (9/9 vs. 4/10; P<0.01). Almost all of them (7/9) had large amounts of small lipid droplets in almost every hepatocyte over the whole liver acinus, and higher NEFA values. At day 45 in postpartum, both groups had mild steatotic changes as initially. A positive correlation between severity of liver damage seric and only aspartate aminotransferase was observed at day 140 in starved animals (P<0.05). This enzyme could be used to assess liver damage, but not alkaline phosphatase. All samples with degeneration corresponded to the microvesicular type. A short starvation period during late pregnancy in ewes produced reversible liver degeneration.


Caraterizaram-se histologicamente as alterações do fígado de ovelhas com toxemia da prenhez. Dez ovelhas foram mantidas em pasto ad libitum, e outras 10 submetidas a jejum a partir do 130º dia de gestação, por até quatro dias. Biopsias hepáticas foram realizadas aos 70, 100, 130 e 140 dias de gestação e, aos 45 dias pós-parto. Níveis séricos de hydroxibutirato, ácidos graxos não esterificados (NEFA), aspartato aminotransferase e fosfatase alcalina foram determinados. O estudo histológico revelou extensão semelhantes de degeneração nos dois grupos no 130º dia de gestação. No 140º dia de gestação, alta proporção de animais submetidos ao jejum, apresentou intensa degeneração no fígado (9/9 vs. 4/10; P<0,01) e, desses, quase todos 7/9 tinham grande quantidade de pequenas gotas de lipídios em quase todos os hepatócitos, nas diferentes regiões do ácino, além de níveis séricos mais elevados de NEFA. Quarenta e cinco dias pós-parto, os animais dos dois grupos apresentaram degeneração discreta, como no início. No 140º dia de gestação, verificou-se correlação positiva entre a severidade das lesões histológicas e a enzima aspartato aminotransferase, nos animais submetidos a jejum (P<0.05). Todas as amostras com degeneração corresponderam ao tipo microvesicular. Um curto período de jejum, na fase final da gestação da ovelha produz degeneração hepática reversível.


Asunto(s)
Animales , Femenino , Hígado/anatomía & histología , Metabolismo , Preeclampsia/veterinaria , Ovinos
19.
Neuroscience ; 157(2): 463-72, 2008 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-18838112

RESUMEN

Despite the well-established sympathoexcitation evoked by chemoreflex activation, the specific sub-regions of the CNS underlying such sympathetic responses remain to be fully characterized. In the present study we examined the effects of intermittent chemoreflex activation in awake rats on Fos-immunoreactivity (Fos-ir) in various subnuclei of the paraventricular nucleus of the hypothalamus (PVN), as well as in identified neurosecretory preautonomic PVN neurons. In response to intermittent chemoreflex activation, a significant increase in the number of Fos-ir cells was found in autonomic-related PVN subnuclei, including the posterior parvocellular, ventromedial parvocellular and dorsal-cap, but not in the neurosecretory magnocellular-containing lateral magnocellular subnucleus. No changes in Fos-ir following chemoreflex activation were observed in the anterior PVN subnucleus. Experiments combining Fos immunohistochemistry and neuronal tract tracing techniques showed a significant increase in Fos-ir in rostral ventrolateral medulla (RVLM)-projecting (PVN-RVLM), but not in nucleus of solitarii tract (NTS)-projecting PVN neurons. In summary, our results support the involvement of the PVN in the central neuronal circuitry activated in response to chemoreflex activation, and indicate that PVN-RVLM neurons constitute a neuronal substrate contributing to the sympathoexcitatory component of the chemoreflex.


Asunto(s)
Bulbo Raquídeo/fisiología , Neuronas/metabolismo , Proteínas Oncogénicas v-fos/metabolismo , Núcleo Hipotalámico Paraventricular/citología , Vigilia , Vías Aferentes/efectos de los fármacos , Vías Aferentes/fisiología , Análisis de Varianza , Animales , Presión Sanguínea/efectos de los fármacos , Presión Sanguínea/fisiología , Frecuencia Cardíaca/efectos de los fármacos , Frecuencia Cardíaca/fisiología , Masculino , Bulbo Raquídeo/efectos de los fármacos , Neuronas/efectos de los fármacos , Núcleo Hipotalámico Paraventricular/efectos de los fármacos , Cianuro de Potasio/farmacología , Ratas , Ratas Wistar
20.
Ginecol Obstet Mex ; 70: 451-6, 2002 Sep.
Artículo en Español | MEDLINE | ID: mdl-12448054

RESUMEN

Fortunately cervical pregnancy, an ectopic gestation that frequently represents obstetric urgency, is a rare entity. We present here the case of a woman who developed cervical pregnancy despite no risk factor associated with ectopic pregnancy was identified. The patient came to the office because of primary sterility of 4 years of evolution. Among her background she reported previous cervical surgery due to benign pathology. She reached pregnancy after medical and surgical treatment. In the week eleven of gestation, the patient presented to the hospital with clinical symptoms of abortion. An ultrasound revealed abdominal pregnancy. Laparotomy was "white", cervix was found enlarged with the external orifice closed, suggesting cervical pregnancy. Conservative treatment consisted in cervical evacuation, endometrial curettage and vaginal tampon. She evolved satisfactorily. We do not know about any previous report of cervical-pregnancy associated with cervical surgery and sterility. We also recognize the need to increase the number of similar cases to generalize results. Thus, it is important to highlight in this case the absence of known risk factors for cervical pregnancy and the background of cervical surgery and sterility. Therefore, we recommend to search for antecedents of cervical surgery and sterility when cervical pregnancy is suspected.


Asunto(s)
Cuello del Útero , Infertilidad Femenina/complicaciones , Embarazo Ectópico , Adulto , Cuello del Útero/patología , Cuello del Útero/cirugía , Femenino , Humanos , Embarazo , Embarazo Ectópico/diagnóstico , Embarazo Ectópico/etiología , Embarazo Ectópico/patología , Embarazo Ectópico/cirugía , Factores de Riesgo , Factores de Tiempo , Enfermedades del Cuello del Útero/cirugía
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