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1.
Biomedicines ; 12(3)2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38540192

RESUMO

Gaucher disease is an inherited disorder in which there is a deficiency of the enzyme glucocerebrosidase, which leads to the accumulation of glucosylceramide. Although much scientific evidence is now available, there is still limited data on the impact on the different life stages of women with this disease. Among other alterations, a delay in menarche has been described, although it has not been related to fertility problems. Menorrhagia is relatively frequent, being related to the presence of thrombocytopenia, thrombocytopathies or coagulation disorders. On the other hand, pregnancy planning is an increasingly frequent concern. All patients should undergo genetic counseling, and it is important to monitor the appearance or worsening of organomegaly, bone and hematologic abnormalities to establish clinical and therapeutic recommendations. Management during the puerperium will depend on the evolution of gestation, and, during the lactation period, the potential appearance of bone complications should be assessed. An early onset of menopause, compared to the general population, has also been described, which may accelerate the development of osteopenia. Finally, although the usual screening protocols for neoplasms are currently being performed, it is recommended to watch for early signs of liver or renal neoplasms when examining the results of imaging tests performed during evaluations for this disease.

2.
Int J Mol Sci ; 24(21)2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37958745

RESUMO

The excessive accumulation of chloride (Cl-) in leaves due to salinity is frequently related to decreased yield in citrus. Two salt tolerance experiments to detect quantitative trait loci (QTLs) for leaf concentrations of Cl-, Na+, and other traits using the same reference progeny derived from the salt-tolerant Cleopatra mandarin (Citrus reshni) and the disease-resistant donor Poncirus trifoliata were performed with the aim to identify repeatable QTLs that regulate leaf Cl- (and/or Na+) exclusion across independent experiments in citrus, as well as potential candidate genes involved. A repeatable QTL controlling leaf Cl- was detected in chromosome 6 (LCl-6), where 23 potential candidate genes coding for transporters were identified using the C. clementina genome as reference. Transcriptomic analysis revealed two important candidate genes coding for a member of the nitrate transporter 1/peptide transporter family (NPF5.9) and a major facilitator superfamily (MFS) protein. Cell wall biosynthesis- and secondary metabolism-related processes appeared to play a significant role in differential gene expression in LCl-6. Six likely gene candidates were mapped in LCl-6, showing conserved synteny in C. reshni. In conclusion, markers to select beneficial Cleopatra mandarin alleles of likely candidate genes in LCl-6 to improve salt tolerance in citrus rootstock breeding programs are provided.


Assuntos
Citrus , Locos de Características Quantitativas , Tolerância ao Sal/genética , Transcriptoma , Citrus/genética , Melhoramento Vegetal , Proteínas de Membrana Transportadoras/genética
3.
Environ Sci Pollut Res Int ; 30(53): 113382-113393, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37848799

RESUMO

Chlorphenamine (CPA) adsorption onto three activated carbons (ACs), namely, Megapol M (MM), Micro 10 (M10), and GAMA B (GB), was studied in this work. The textural properties, concentrations of active sites, surface charge and point of zero charge of the ACs were assessed. The surface areas (SBET) of MM, GB and M10 were 1107, 812 and 766 m2/g, respectively. The MM surface had an acidic character, while the surfaces of M10 and GB were basic. The adsorption capacity of MM, M10, and GB towards CPA was studied at pH 7 and 11, and the adsorption capacity decreased in the order MM > M10 ≈ GB, which was ascribed to the magnitude of SBET and the concentration of acidic sites. The solution pH significantly increased the adsorption capacity of MM towards CPA by raising the solution pH from 5 to 9, and this behavior was attributed to the electrostatic attraction between the negatively charged surface of MM and the cationic species of CPA. The maximum uptake of CPA adsorbed on MM was 574.6 mg/g at pH = 11 and T = 25 °C. The adsorption capacity of MM was slightly raised by incrementing the temperature. Lastly, the zeta potential measurements of pristine MM and MM saturated with CPA confirmed that the electrostatic attraction predominated in the pH range of 5-9, and the π-π stacking interactions were the principal mechanism of CPA adsorption on MM at pH 11.


Assuntos
Carvão Vegetal , Clorfeniramina , Carvão Vegetal/química , Adsorção , Concentração de Íons de Hidrogênio , Temperatura , Propriedades de Superfície
4.
J Exp Bot ; 74(19): 5970-5988, 2023 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-37668424

RESUMO

Deterioration and impoverishment of soil, caused by environmental pollution and climate change, result in reduced crop productivity. To adapt to hostile soils, plants have developed a complex network of factors involved in stress sensing, signal transduction, and adaptive responses. The chemical properties of reactive oxygen species (ROS) and reactive nitrogen species (RNS) allow them to participate in integrating the perception of external signals by fine-tuning protein redox regulation and signal transduction, triggering specific gene expression. Here, we update and summarize progress in understanding the mechanistic basis of ROS and RNS production at the subcellular level in plants and their role in the regulation of ion channels/transporters at both transcriptional and post-translational levels. We have also carried out an in silico analysis of different redox-dependent modifications of ion channels/transporters and identified cysteine and tyrosine targets of nitric oxide in metal transporters. Further, we summarize possible ROS- and RNS-dependent sensors involved in metal stress sensing, such as kinases and phosphatases, as well as some ROS/RNS-regulated transcription factors that could be involved in metal homeostasis. Understanding ROS- and RNS-dependent signaling events is crucial to designing new strategies to fortify crops and improve plant tolerance of nutritional imbalance and metal toxicity.


Assuntos
Óxido Nítrico , Espécies Reativas de Nitrogênio , Espécies Reativas de Oxigênio/metabolismo , Óxido Nítrico/metabolismo , Espécies Reativas de Nitrogênio/metabolismo , Plantas/metabolismo , Oxirredução , Metais/metabolismo , Canais Iônicos/metabolismo
5.
Int Emerg Nurs ; 69: 101315, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37348237

RESUMO

INTRODUCTION: Mental workload refers to the cognitive or intellectual requirements that a worker is subjected to in a workday. The objective of the present work was to discover the subjective mental workload of nursing staff at Hospital Emergency Units, and its relationship with sociodemographic, work, environmental factors at the workplace, and personality variables. METHOD: A quantitative, descriptive, observational, and crosssectional study was conducted with 201 emergency nurses from 13 different provinces in Spain. Each participant completed 5 questionnaires (sociodemographic, work conditions, environmental conditions, personality, and subjective mental workload). Descriptive statistics were obtained, and Pearson's correlations and multivariate models (multiple linear regression) were performed. RESULTS: The nurses had medium to high levels of mental workload. The environmental conditions had a direct relationship with the mental workload, especially with respect to noise and lighting. The participants obtained high scores in kindness, responsibility, openness/intellect, and extraversion. Positive and statistically significant relations were found between neuroticism and mental workload. Being female, older, and having stable employment or a permanent contract were associated with a greater mental workload of emergency nurses. CONCLUSION: The domain of neuroticism personality, and the hygienic conditions in the workplace were the predictors with the most weight in the model. This study could be useful for defining aspects that need to be considered for the well-being of emergency nurses, such as lighting conditions or environmental noise in the workplace. It also invites reflection on the influence of personal factors (age, gender, personality) and work factors (type of contract, professional experience) on the mental workload of emergency nurses.


Assuntos
Enfermeiras e Enfermeiros , Recursos Humanos de Enfermagem Hospitalar , Recursos Humanos de Enfermagem , Feminino , Humanos , Masculino , Recursos Humanos de Enfermagem Hospitalar/psicologia , Personalidade , Inquéritos e Questionários , Carga de Trabalho/psicologia , Local de Trabalho/psicologia
6.
Materials (Basel) ; 15(17)2022 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-36079518

RESUMO

CO2 adsorption on bare 3d transition-metal nanoclusters and 3d transition-metal nanoclusters supported on pyridinic N3-doped graphene (PNG) was investigated by employing the density functional theory. First, the interaction of Co13 and Cu13 with PNG was analyzed by spin densities, interaction energies, charge transfers, and HUMO-LUMO gaps. According to the interaction energies, the Co13 nanocluster was adsorbed more efficiently than Cu13 on the PNG. The charge transfer indicated that the Co13 nanocluster donated more charges to the PNG nanoflake than the Cu13 nanocluster. The HUMO-LUMO gap calculations showed that the PNG improved the chemical reactivity of both Co13 and Cu13 nanoclusters. When the CO2 was adsorbed on the bare 3d transition-metal nanoclusters and 3d transition-metal nanoclusters supported on the PNG, it experienced a bond elongation and angle bending in both systems. In addition, the charge transfer from the nanoclusters to the CO2 molecule was observed. This study proved that Co13/PNG and Cu13/PNG composites are adequate candidates for CO2 adsorption and activation.

7.
Int J Mol Sci ; 23(9)2022 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-35563521

RESUMO

Salt tolerance is a target trait in plant science and tomato breeding programs. Wild tomato accessions have been often explored for this purpose. Since shoot Na+/K+ is a key component of salt tolerance, RNAi-mediated knockdown isogenic lines obtained for Solanum galapagense alleles encoding both class I Na+ transporters HKT1;1 and HKT1;2 were used to investigate the silencing effects on the Na and K contents of the xylem sap, and source and sink organs of the scion, and their contribution to salt tolerance in all 16 rootstock/scion combinations of non-silenced and silenced lines, under two salinity treatments. The results show that SgHKT1;1 is operating differently from SgHKT1;2 regarding Na circulation in the tomato vascular system under salinity. A model was built to show that using silenced SgHKT1;1 line as rootstock would improve salt tolerance and fruit quality of varieties carrying the wild type SgHKT1;2 allele. Moreover, this increasing effect on both yield and fruit soluble solids content of silencing SgHKT1;1 could explain that a low expressing HKT1;1 variant was fixed in S. lycopersicum during domestication, and the paradox of increasing agronomic salt tolerance through silencing the HKT1;1 allele from S. galapagense, a salt adapted species.


Assuntos
Proteínas de Transporte de Cátions , Solanum lycopersicum , Solanum , Proteínas de Transporte de Cátions/genética , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo , Melhoramento Vegetal , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Potássio/metabolismo , Salinidade , Sódio/metabolismo , Solanum/genética
8.
Plant Physiol Biochem ; 168: 282-293, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34673319

RESUMO

We analyzed the physiological impact of function loss on cheesmaniae alleles at the HKT1;1 and HKT1;2 loci in the roots and aerial parts of tomato plants in order to determine the relative contributions of each locus in the different tissues to plant Na+/K+ homeostasis and subsequently to tomato salt tolerance. We generated different reciprocal rootstock/scion combinations with non-silenced, single RNAi-silenced lines for ScHKT1;1 and ScHKT1;2, as well as a silenced line at both loci from a near isogenic line (NIL14), homozygous for the Solanum cheesmaniae haplotype containing both HKT1 loci and subjected to salinity under natural greenhouse conditions. Our results show that salt treatment reduced vegetative growth and altered the Na+/K+ ratio in leaves and flowers; negatively affecting fruit production, particularly in graft combinations containing single silenced ScHKT1;2- and double silenced ScHKT1;1/ScHKT1;2 lines when used as scion. We concluded that the removal of Na+ from the xylem by ScHKT1;2 in the aerial part of the plant can have an even greater impact than that on Na+ homeostasis at the root level under saline conditions. Also, ScHKT1;1 function loss in rootstock greatly reduced the Na+/K+ ratio in leaf and flower tissues, minimized yield loss under salinity. Our results suggest that, in addition to xylem Na+ unloading, ScHKT1;2 could also be involved in Na+ uploading into the phloem, thus promoting Na+ recirculation from aerial parts to the roots. This recirculation of Na+ to the roots through the phloem could be further favoured by ScHKT1;1 silencing at these roots.


Assuntos
Solanum lycopersicum , Alelos , Flores , Solanum lycopersicum/genética , Folhas de Planta , Raízes de Plantas/genética , Potássio , Tolerância ao Sal/genética
9.
J Vet Res ; 64(3): 373-379, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32984626

RESUMO

INTRODUCTION: Antimicrobial resistance is a global health threat. It has been studied in humans and domestic animals, but there is a lack of data on wild animals. The objective of this study is the elucidation of its patterns in Staphylococcus spp. isolated from wild mammals of the Autonomous Community of Aragón (Spain). MATERIAL AND METHODS: A total of 103 mammals (Artiodactyla, Carnivora, Chiroptera, Erinaceomorpha, and Lagomorpha) were studied. A recovery centre provided 32 and hunting 71. Nasal and faecal samples yielded 111 staphylococci, which were identified by matrix-assisted laser desorption/ionization-time of flight mass spectrometry. A susceptibility test to 11 antibiotics was carried out, and statistical analysis was performed. RESULTS: Some differences were detected in bacterial prevalence depending on how the mammal fed. Artiodactyla, mainly hunted, were predisposed to carry coagulase-positive staphylococci. The staphylococci species recovered were resistant to at least two classes of antibiotics, and were disseminated in all of the geographical areas studied. CONCLUSION: Resistant staphylococci are widely distributed in the wild mammals in the areas of the study, but the resistance quantified in them is lower than that to be expected if the use of antibiotics in farms had a direct influence on the wildlife and its environment. On the other hand, resistance to antibiotics restricted to human use was widely disseminated in various wild animal species.

10.
Plant Physiol Biochem ; 154: 341-352, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32604062

RESUMO

Genes encoding HKT1-like Na+ transporters play a key role in the salinity tolerance mechanism in Arabidopsis and other plant species by retrieving Na+ from the xylem of different organs and tissues. In this study, we investigated the role of two HKT1;2 allelic variants in tomato salt tolerance in relation to vegetative growth and fruit yield in plants subjected to salt treatment in a commercial greenhouse under real production conditions. We used two near-isogenic lines (NILs), homozygous for either the Solanum lycopersicum (NIL17) or S. cheesmaniae (NIL14) allele, at HKT1;2 loci and their respective RNAi-Sl/ScHKT1;2 lines. The results obtained show that both ScHKT1;2- and SlHKT1;2-silenced lines display hypersensitivity to salinity associated with an altered leaf Na+/K+ ratio, thus confirming that HKT1;2 plays an important role in Na+ homeostasis and salinity tolerance in tomato. Both silenced lines also showed Na+ over-accumulation and a slight, but significant, reduction in K+ content in the flower tissues of salt-treated plants and consequently a higher Na+/K+ ratio as compared to the respective unsilenced lines. This altered Na+/K+ ratio in flower tissues is associated with a sharp reduction in fruit yield, measured as total fresh weight and number of fruits, in both silenced lines under salinity conditions. Our findings demonstrate that Na+ transporter HKT1;2 protects the flower against Na+ toxicity and mitigates the reduction in tomato fruit yield under salinity conditions.


Assuntos
Proteínas de Transporte de Cátions/fisiologia , Proteínas de Plantas/fisiologia , Estresse Salino , Solanum lycopersicum/fisiologia , Flores/química , Frutas/crescimento & desenvolvimento , Potássio/metabolismo , Sódio/química
12.
J Relig Health ; 56(1): 149-157, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26852419

RESUMO

This article describes Puerto Rican physicians' personal and clinical utilization of complementary and alternative medicines (CAM), its effects, and use as they identified as either Spiritist, spiritual or religious. Semi-structured interviews were conducted with 74 doctors in Puerto Rico. Major themes and relationships among them were charted using the qualitative data analysis program MAXQDA, open coding and grounded theory. Thirty-one doctors spoke of CAM and its use as related to their spiritual or religious perspectives. Spiritual or Spiritist doctors were more inclined than religious doctors to utilize CAM. Seeking closer relationships with patients was related to a spiritually oriented goal of healing (as distinct from curing) as a reason to recommend CAM.


Assuntos
Terapias Complementares/métodos , Médicos , Espiritualidade , Humanos , Entrevistas como Assunto , Porto Rico , Religião e Medicina
13.
Cells Tissues Organs ; 201(1): 51-64, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26565958

RESUMO

PURPOSE: We evaluated the effect of peroxisome proliferator-activated receptor (PPAR) agonists on the differentiation and metabolic features of bovine bone marrow-derived mesenchymal cells induced to adipogenic or myogenic lineages. METHODS: Cells isolated from 7-day-old calves were cultured in basal medium (BM). For adipogenic differentiation, cells were cultured for one passage in BM and then transferred to a medium supplemented with either rosiglitazone, telmisartan, sirtinol or conjugated c-9, t-11 linoleic acid; for myogenic differentiation, third-passage cells were added with either bezafibrate, telmisartan or sirtinol. The expression of PPARx03B3; (an adipogenic differentiation marker), myosin heavy chain (MyHC; a myogenic differentiation marker) and genes related to energy metabolism were measured by quantitative real-time PCR in a completely randomized design. RESULTS: For adipogenic differentiation, 20 µM telmisartan showed the highest PPARx03B3; expression (15.58 ± 0.62-fold, p < 0.0001), and differences in the expression of energy metabolism-related genes were found for hexokinase II, phosphofructokinase, adipose triglyceride lipase, acetyl-CoA carboxylase α(ACACα) and fatty acid synthase (p < 0.001), but not for ACACß (p = 0.4275). For myogenic differentiation, 200 µM bezafibrate showed the highest MyHC expression (73.98 ± 11.79-fold), and differences in the expression of all energy metabolism-related genes were found (p < 0.05). CONCLUSIONS: Adipocyte and myocyte differentiation are enhanced with telmisartan and bezafibrate, respectively, and energy uptake, storage and mobilization are improved with both.


Assuntos
Adipogenia/efeitos dos fármacos , Metabolismo Energético/genética , Células-Tronco Mesenquimais/citologia , Desenvolvimento Muscular/efeitos dos fármacos , Receptores Ativados por Proliferador de Peroxissomo/agonistas , Adipócitos/citologia , Adipogenia/fisiologia , Animais , Benzamidas/farmacologia , Benzimidazóis/farmacologia , Benzoatos/farmacologia , Bezafibrato/farmacologia , Células da Medula Óssea/citologia , Bovinos , Linhagem da Célula/fisiologia , Metabolismo Energético/fisiologia , Ácidos Linoleicos/farmacologia , Desenvolvimento Muscular/fisiologia , Cadeias Pesadas de Miosina/biossíntese , Naftóis/farmacologia , PPAR gama/biossíntese , Reação em Cadeia da Polimerase em Tempo Real , Rosiglitazona , Telmisartan , Tiazolidinedionas/farmacologia
14.
Cir Cir ; 82(5): 511-6, 2014.
Artigo em Espanhol | MEDLINE | ID: mdl-25259430

RESUMO

BACKGROUND: Traumatic hand injuries are among the principal types of injuries. These injuries refer to any acute damage caused to the hand by an external agent. The aim of this study was to determine the characteristics of these injuries in our unit. OBJECTIVE: To determine the characteristics of hand injuries at the Plastic and Reconstructive Surgery of the Centro Médico "Licenciado Adolfo López Mateos" (CMLALM) and compare the results with those reported in other countriesMethods: Retrospective study of patients diagnosed with traumatic hand injury treated at the Plastic and Reconstructive Surgery service at CMLALM during the period from September 6, 2010 to September 5, 2011. RESULTS: One hundred five cases were treated. There was a predominance of males (82.9%). The most affected group was 20-29 years old (44.8%). The right hand was the most injured (46.7%). The most common mechanism of injury was due to abrasion (41%) followed by sharp objects (32.4%). The dominant hand was the most damaged (50.47%). The most common injuries were open type (88.6%) and single type (84.8%). CONCLUSIONS: Hand injuries were more common in men and were occupationally related; therefore, occupational safety programs must be improved. The characteristics of traumatic hand injuries in our unit were very similar to those seen worldwide.


Antecedentes: las lesiones traumáticas de la mano se encuentran entre los tipos más frecuentes de lesiones y se refieren al daño agudo ocasionado a la mano por un agente externo. Objetivo: determinar las características de las lesiones de mano atendidas en el Centro Médico Lic. Adolfo López Mateos, ISEM y compararlas con lo reportado en otros países. Material y métodos: estudio retrospectivo de pacientes atendidos en el servicio de Cirugía Plástica y Reconstructiva del Centro Médico Licenciado Adolfo López Mateos, entre el 6 de septiembre de 2010 y el 5 de septiembre de 2011, con diagnóstico de lesión traumática de mano. Resultados: se atendieron 105 casos. Predominó el sexo masculino (82.9%). El límite de edad más afectado fue el de 20 a 29 años (44.8%). La mano más lesionada fue la derecha (46.7%). El mecanismo de lesión más común fue por esmeril (41%), seguido por objeto cortante (32.4%). La mano dominante fue la más lesionada (50.47%). Las lesiones más comunes fueron de tipo abierto (88.6%), y simple (84.8%). Conclusiones: las lesiones de mano fueron más comunes en hombres, en sitios de actividad laboral, por lo que deben mejorarse los programas de seguridad en el trabajo. Las características de las lesiones traumáticas de mano en nuestra unidad fueron muy semejantes a las observadas en el resto del mundo.


Assuntos
Traumatismos da Mão/epidemiologia , Acidentes de Trabalho/estatística & dados numéricos , Adulto , Idoso , Mordeduras e Picadas/epidemiologia , Queimaduras por Corrente Elétrica/epidemiologia , Feminino , Humanos , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Traumatismos Ocupacionais/epidemiologia , Estudos Retrospectivos , Ferimentos por Arma de Fogo/epidemiologia , Ferimentos Perfurantes/epidemiologia , Adulto Jovem
15.
J Behav Health Serv Res ; 37(1): 124-43, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19330453

RESUMO

To assess mental health status among Latinos, culturally and linguistically appropriate instruments are needed. The purpose of this study was to assess psychometric properties and sensitivity of the Spanish revised Behavior and Symptom Identification Scale (BASIS-24), a self-report mental health assessment instrument first developed and validated in English. The Spanish translation was field tested among Spanish-speaking recipients of inpatient (N = 283) or outpatient (N = 311) mental health services in Massachusetts, Puerto Rico, and California. BASIS-24 was completed within 72 h of admission and up to 48 h before discharge (for inpatients) or at intake and 30-60 days later for outpatients. Confirmatory factor analysis indicated adequate fit for the model obtained from the English instrument. Internal consistency reliability exceeded 0.70 for five of the six factors. Concurrent and discriminant validity were partially supported. Improvement following treatment was statistically significant, with small to moderate effect sizes.


Assuntos
Inquéritos Epidemiológicos , Transtornos Mentais/diagnóstico , Saúde Mental/estatística & dados numéricos , Psicometria/normas , Inquéritos e Questionários/normas , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Hispânico ou Latino/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
16.
Rev. biol. trop ; 56(4): 1825-1835, Dec. 2008. ilus
Artigo em Inglês | LILACS | ID: lil-637780

RESUMO

the structural and ultrastructural features of gonads from endemic Mexican fish have received scarce attention. This study describes the histological and ultrastructural characteristics of the oocyte in Chirostoma humboldtianum. The ovary is asynchronic, and as such, most phases of oocyte development are found in the same ovary. The complete process of oogenesis was divided in five stages: oogonium and folliculogenesis, primary growth, cortical alveoli and lipid inclusions, vitellogenesis and maturation. The presence of big filaments, which appear at the end of primary growth, induces some common follicular adaptation. During primary growth, abundant ribosomes, rough endoplasmic reticulum, and mitochondria are grouped in the cytoplasm. At the end of this stage, the Z1 layer of the chorion is developed, while microvilli start to be evident as well. In the cortical alveoli and lipid droplets phase, intense PAS positive vesicles, some of them containing nucleoid material, are observed in the peripheral cytoplasm and the lipid droplets take a more central position. In vitellogenesis, the proteic yolk accumulates in a centripetal way while the chorion is completely formed. In maturation, the germinal vesicle migrates to the animal pole, meiosis is restored, and there is nuclear breakdown. The oocyte increases its size and holds some oil droplets and a big fluid mass of yolk. On the outside, filaments surround the oocyte completely. Rev. Biol. Trop. 56 (4): 1825-1835. Epub 2008 December 12.


Los aspectos estructurales y ultraestructrurales de las gónadas de peces mexicanos endémicos han sido poco estudiados. En el presente trabajo reportamos las características histológicas y ultraestructurales del ovocito de Chirostoma hulmboldtianum. El ovario es de tipo asincrónico, por ende, la mayoría de las fases del desarrollo del ovocito pueden ser encontradas en el mismo ovario. El desarrollo del ovocito fue dividido en cinco etapas: ovo-gonia y foliculogénesis, crecimiento primario del ovocito, inclusiones lipídicas y gránulos corticales, vitelogénesis y maduración. La presencia de grandes filamentos que aparecen al final de la etapa de crecimiento primario, inducen adaptaciones foliculares. Durante el crecimiento primario, en el citoplasma se encuentran abundantes ribosomas, retículo endoplásmico rugoso y agrupamientos de mitocondrias. Al final de esta etapa, inicia el desarrollo de la capa Z1 del corion, comenzando a ser evidentes las microvellosidades del ovocito. Durante la etapa de inclusiones lipídicas y gránulos corticales, vesículas PAS positivas, algunas de ellas con material nucleoide, se ubican en la periferia del ovocito, mientras que las que contienen material graso toman una posición más central en la célula. Durante la vitelogénesis se presenta una acumulación de vitelo protéico en un sentido centrípeto; durante esta etapa, el corion está completamente formado. En la maduración, la vesicular germinal migra hacia el polo animal, se reinicia la meiosis y se rompe la envoltura nuclear. El ovocito incrementa su tamaño y en el citoplasma se pueden observar algunas gotas de grasa y el vitelo se presenta como una gran masa acuosa. En el exterior, los filamentos rodean completamente al ovocito.


Assuntos
Animais , Feminino , Peixes/anatomia & histologia , Oócitos/ultraestrutura , Oogênese/fisiologia , Ovário/ultraestrutura , México , Oócitos/crescimento & desenvolvimento , Ovário/anatomia & histologia , Ovário/fisiologia
17.
Rev Biol Trop ; 56(4): 1825-35, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19419084

RESUMO

The structural and ultrastructural features of gonads from endemic Mexican fish have received scarce attention. This study describes the histological and ultrastructural characteristics of the oocyte in Chirostoma humboldtianum. The ovary is asynchronic, and as such, most phases of oocyte development are found in the same ovary. The complete process of oogenesis was divided in five stages: oogonium and folliculogenesis, primary growth, cortical alveoli and lipid inclusions, vitellogenesis and maturation. The presence of big filaments, which appear at the end of primary growth, induces some common follicular adaptation. During primary growth, abundant ribosomes, rough endoplasmic reticulum, and mitochondria are grouped in the cytoplasm. At the end of this stage, the Z1 layer of the chorion is developed, while microvilli start to be evident as well. In the cortical alveoli and lipid droplets phase, intense PAS positive vesicles, some of them containing nucleoid material, are observed in the peripheral cytoplasm and the lipid droplets take a more central position. In vitellogenesis, the proteic yolk accumulates in a centripetal way while the chorion is completely formed. In maturation, the germinal vesicle migrates to the animal pole, meiosis is restored, and there is nuclear breakdown. The oocyte increases its size and holds some oil droplets and a big fluid mass of yolk. On the outside, filaments surround the oocyte completely.


Assuntos
Peixes/anatomia & histologia , Oócitos/ultraestrutura , Oogênese/fisiologia , Ovário/ultraestrutura , Animais , Feminino , México , Oócitos/crescimento & desenvolvimento , Ovário/anatomia & histologia , Ovário/fisiologia
18.
J Pediatr Endocrinol Metab ; 17(9): 1221-9, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15506682

RESUMO

BACKGROUND: Growth after pediatric liver transplantation (LT) has been the subject of reviews. The conclusions have not been consistent. OBJECTIVE: To describe post-LT growth patterns in prepubertal liver transplant recipients and identify variables affecting their growth. METHODS: Sixty-seven prepubertal transplant recipients met the inclusion criteria. Variables assessed were age, sex, pretransplant lack of growth, type of transplantation, primary diagnosis, liver and kidney function at one year post-LT, complications and retransplantation, prednisone therapy duration, allograft rejection episodes during the first year, cholesterol, triglycerides and immunosuppressive regimen. Mean follow-up was 3.5 years (range: 2-6 years). RESULTS: Growth according to baseline z-score, indications for transplantation and steroid withdrawal showed significant differences at 2 years post-LT. CONCLUSIONS: The causes of poorest z-scores in height post-LT were: height z-scores under -2.0 at transplantation, metabolic diagnosis, and use of steroids beyond 1 year post-LT.


Assuntos
Desenvolvimento Infantil/fisiologia , Transtornos do Crescimento/etiologia , Imunossupressores/uso terapêutico , Transplante de Fígado/efeitos adversos , Adolescente , Fatores Etários , Estatura/fisiologia , Peso Corporal/fisiologia , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Seguimentos , Sobrevivência de Enxerto , Transtornos do Crescimento/diagnóstico , Humanos , Imunossupressores/efeitos adversos , Transplante de Fígado/métodos , Masculino , Estudos Retrospectivos , Fatores Sexuais , Fatores de Tempo , Imunologia de Transplantes/fisiologia
19.
J Pediatr Endocrinol Metab ; 17(8): 1097-103, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15379421

RESUMO

BACKGROUND: The reported incidence of catch-up growth following orthotopic liver transplantation (OLT) ranges widely, from 0% to 97%. OBJECTIVE: We undertook bivariate analysis of multiple factors that might affect post-OLT growth in children undergoing OLT, and described the results with different parameters used to determine catch-up growth. METHODS: Eighty patients met the inclusion criteria. RESULTS: Catch-up growth occurred in 14% during the first 6 months, 15% at 1 year, 39% at 2 years, 16% between 3 and 6 years, and 16% after 6 years post-OLT. The earlier catch-up growth was shown in metabolic diagnosis, patients over 10 years old and those without steroids at 1 year post-OLT. CONCLUSIONS: It is difficult to determine an acceptable definition of catch-up growth. We suggest that Zvel score > or =0 is the best parameter to evaluate catch-up growth, since the results are more normally distributed. Patients with prednisone withdrawal later than 1 year post-OLT and those with diagnosis of hepatitis and cirrhosis showed the slowest catch-up growth.


Assuntos
Estatura , Crescimento/fisiologia , Transplante de Fígado/fisiologia , Adolescente , Peso Corporal , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Masculino , Estatísticas não Paramétricas
20.
Clin Transplant ; 17(3): 249-53, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12780676

RESUMO

BACKGROUND: The diagnosis and treatment of diarrhea in liver transplant recipients often pose a challenge owing to the variety of infectious and non-infectious causes. However, diagnosis is principally focused on ruling out an infectious etiology. Tacrolimus, an immunosuppressive agent generally used after liver transplantation, is absorbed mainly from the duodenum through the upper jejunum. It can be assumed that metabolism of the drug will be influenced by diarrhea. METHODS: Four liver transplant recipients who developed an episode of acute gastroenteritis. Infectious etiology was confirmed; trough tacrolimus levels were measured before, during and after gastroenteritis. RESULTS: All patients presented a two- to three-fold increase in blood tacrolimus levels after the onset of gastroenteritis. CONCLUSIONS: Until the role played by the intestine in the metabolism of tacrolimus is fully understood, it is prudent to recommend early dose reduction of tacrolimus and careful monitoring of trough levels during diarrheal disorders of any nature in pediatric liver-transplanted patients.


Assuntos
Diarreia/sangue , Gastroenterite/sangue , Imunossupressores/sangue , Transplante de Fígado , Complicações Pós-Operatórias/sangue , Tacrolimo/sangue , Doença Aguda , Pré-Escolar , Diarreia/etiologia , Feminino , Gastroenterite/complicações , Humanos , Imunossupressores/administração & dosagem , Imunossupressores/uso terapêutico , Lactente , Mucosa Intestinal/metabolismo , Masculino , Complicações Pós-Operatórias/etiologia , Tacrolimo/administração & dosagem , Tacrolimo/uso terapêutico
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