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1.
Animal ; 15(3): 100135, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33573959

RESUMEN

Knowledge of periparturient longitudinal changes in sow microbiota composition is necessary to fully understand her role in the development of the piglet microbiota, but also to improve gut health and performance of the sow in lactation. Primiparous sows face the challenge of partitioning nutrients to support maternal growth in addition to supporting foetal growth and the demands of lactation. Additional metabolic stress present during the periparturient period may induce changes in the microbiota profile between primiparous and multiparous sows. Using 16S rRNA gene sequencing, the study aimed to characterise the longitudinal changes in the periparturient microbiota and identify differences within the sow microbiota profile associated with parity. Faecal samples from primiparous (n = 13) and multiparous (n = 16) sows were collected at four different time points (day -6, -1, 3 and 8) in relation to farrowing (day 0). Microbiota richness was lowest on day 3 and -1 of the periparturient period (P < 0.05). Microbiota community composition, assessed by weighted and unweighted UniFrac distances, demonstrated longitudinal changes, with day 3 samples clustering away from all other sampling time points (P < 0.05). The relative abundance of several genera segregated gestation from lactation samples including Roseburia, Prevotella 1, Prevotella 2, Christensenellaceae R-7 group, Ruminococcaceae UCG-002 and Ruminococcaceae UCG-010 (P < 0.01). Furthermore, day 3 was characterised by a significant increase in the relative abundance of Escherichia/Shigella, Fusobacterium and Bacteroides, and a decrease in Alloprevotella, Prevotellaceae UCG-003 and Ruminococcus 1 (P < 0.001). Primiparous sows had overall lower periparturient microbiota diversity (P < 0.01) and there was a significant interaction between parity and sampling time point, with primiparous sows having lower microbiota richness on day -6 (P < 0.001). There was a significant interaction between sow parity and sampling time point on microbiota composition on day -6 and -1 (unweighted UniFrac distances;  ≤ 0.01) and day 8 (weighted and unweighted UniFrac distances; P < 0.05). Whilst no significant interactions between sow parity and sampling day were observed for genera relative abundances, multiparous sows had a significantly higher relative abundance of Bacteroidetes dgA-11 gut group and Prevotellaceae UCG-004 (P < 0.01). This study demonstrates that the sow microbiota undergoes longitudinal changes, which are collectively related to periparturient changes in the sow environment, diet and physiological changes to support foetal growth, delivery and the onset of lactation, but also sow parity.


Asunto(s)
Lactancia , Microbiota , Animales , Dieta , Femenino , Paridad , Embarazo , ARN Ribosómico 16S/genética , Porcinos
2.
SSM Popul Health ; 2: 613-622, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29349175

RESUMEN

Bridging social capital is defined as the connections between individuals who are dissimilar with respect to socioeconomic and other characteristics. There is an important gap in the literature related to its measurement. We describe the development and validation of a questionnaire to measure bridging social capital. We focused the development of the questionnaire to be suitable for use in Latino immigrant populations in the U.S. The structure of the questionnaire comprised the following: Socialization in the job place (5 items); Membership in community activities (16 items); Participation in community activities (5 items); Contact with similar/different people (7 items); Assistance (17 items); Trust of institutions, corporations and other people(14 items); and Trust of intimate people (3 items). First, we used focus groups (N=17 participants) to establish content validity with an inductive thematic analysis to identify themes and subthemes. Changes were made to the questionnaire based on difficulty, redundancy, length and semantic equivalence. Second, we analyzed the questionnaire's psychometric properties (N=138). We tested internal consistency with Cronbach alpha and construct validity with a Confirmatory Factor Analysis (CFA) for each sub-scale to test theoretical unity; discriminant validity to observe differences between participants from high and low SES backgrounds and different language; and content validity with an independent expert panel. Cronbach alphas ranged from 0.80 (Assistance) to 0.92 (Trust). CFA results indicated that CFI and TLI were higher than 0.90 in almost all the scales, with high factor loadings. The Wilcoxon tests indicated that there were statistically significant mean differences between SES and language groups (p<0.00). The independent expert panel determined that the questionnaire had good content validity. This is the first demonstration of a psychometrically validated questionnaire to measure bridging social capital in an immigrant population in the United States. Our questionnaire may be suitable for further refinement and adaptation to other immigrant groups in different countries.

3.
Cancer Causes Control ; 26(11): 1699-707, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26376892

RESUMEN

PURPOSE: The purpose of this study was to examine material hardship among smokers to determine whether such hardship was positively associated with current attempts to quit tobacco use. METHODS: We analyzed cross-sectional data from the Health in Common (HIC) study, an observational study to investigate social and physical determinants of cancer risk-related behaviors among residents of low-income housing in three cities in the Boston metropolitan area. In this study, three indicators of hardship were used: food hardship, financial hardship, and material hardship (food and financial hardship combined). Logistic regression models were used to obtain the odds of currently trying to quit among current smokers in the HIC (n = 170) across hardship types experienced, adjusting for sociodemographic and psychosocial factors. RESULTS: Fully adjusted models revealed no statistically significant association between trying to quit tobacco use and indicators of material hardship: food hardship and financial hardship present (OR 1.33 (0.42-4.2); food hardship and no financial hardship OR 3.83 (0.97-15.13); and financial hardship but no food hardship OR 0.5 (0.1-2.39). CONCLUSIONS: These findings suggest that even in the presence of material hardship, low-income housing resident tobacco users are not more likely to quit tobacco use; therefore, cessation efforts focused on the financial benefits of quitting may be insufficient to motivate quit attempts among low-income smokers.


Asunto(s)
Motivación , Pobreza/psicología , Cese del Hábito de Fumar/economía , Tabaquismo/economía , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Boston , Estudios Transversales , Femenino , Vivienda , Humanos , Masculino , Persona de Mediana Edad , Asunción de Riesgos , Cese del Hábito de Fumar/psicología , Tabaquismo/psicología , Adulto Joven
4.
Cell Death Dis ; 6: e1588, 2015 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-25569105

RESUMEN

Prolonged culture of embryonic stem cells (ESCs) leads them to adopt embryonal carcinoma cell features, creating enormous dangers for their further application. The mechanism involved in ESC stability has not, however, been extensively studied. We previously reported that SMAD family member 3 (Smad3) has an important role in maintaining mouse ESC stability, as depletion of Smad3 results in cancer cell-like properties in ESCs and Smad3-/- ESCs are prone to grow large, malignant teratomas. To understand how Smad3 contributes to ESC stability, we performed microarray analysis to compare the transcriptome of wild-type and Smad3-/- ESCs. We found that Rif1 (RAP1-associated protein 1), a factor important for genomic stability, is significantly upregulated in Smad3-/- ESCs. The expression level of Rif1 needs to be tightly controlled in ESCs, as a low level of Rif1 is associated with ESC differentiation, but a high level of Rif1 is linked to ESC transformation. In ESCs, Oct4 activates Rif1, whereas Smad3 represses its expression. Oct4 recruits Smad3 to bind to Rif1 promoter, but Smad3 joining facilitates the loading of a polycomb complex that generates a repressive epigenetic modification on Rif1 promoter, and thus maintains the expression of Rif1 at a proper level in ESCs. Interestingly, Rif1 short hairpin RNA (shRNA)-transduced Smad3-/- ESCs showed less malignant properties than the control shRNA-transduced Smad3-/- ESCs, suggesting a critical role of Rif1 in maintaining the stability of ESCs during proliferation.


Asunto(s)
Células Madre Embrionarias/citología , Células Madre Embrionarias/metabolismo , Factor 3 de Transcripción de Unión a Octámeros/metabolismo , Proteína smad3/metabolismo , Proteínas de Unión a Telómeros/metabolismo , Animales , Diferenciación Celular/efectos de la radiación , Movimiento Celular/efectos de la radiación , Proliferación Celular/efectos de la radiación , Reparación del ADN/efectos de la radiación , Células Madre Embrionarias/efectos de la radiación , Perfilación de la Expresión Génica , Regulación del Desarrollo de la Expresión Génica/efectos de la radiación , Técnicas de Silenciamiento del Gen , Histonas/metabolismo , Lisina/metabolismo , Metilación/efectos de la radiación , Ratones , Modelos Biológicos , Regiones Promotoras Genéticas/genética , Unión Proteica/efectos de la radiación , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Interferente Pequeño/metabolismo , Proteína smad3/deficiencia , Proteína smad3/genética , Proteínas de Unión a Telómeros/genética , Teratoma/patología , Rayos Ultravioleta
5.
Plant Cell Environ ; 38(1): 23-34, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24725255

RESUMEN

Maize seedlings emit sesquiterpenes during the day in response to insect herbivory. Parasitoids and predators use induced volatile blends to find their hosts or prey. To investigate the diurnal regulation of biosynthesis and emission of induced sesquiterpenes, we applied linolenoyl-L-glutamine (LG) to maize seedlings in the morning or evening using a cut-stem assay and tracked farnesene emission, in planta accumulation, as well as transcript levels of farnesyl pyrophosphate synthase 3 (ZmFPPS3) and terpene synthase10 (ZmTPS10) throughout the following day. Independent of time of day of LG treatment, maximum transcript levels of ZmFPPS3 and ZmTPS10 occurred within 3-4 h after elicitor application. The similarity between the patterns of farnesene emission and in planta accumulation in light-exposed seedlings in both time courses suggested unobstructed emission in the light. After evening induction, farnesene biosynthesis increased dramatically during early morning hours. Contrary to light-exposed seedlings dark-kept seedlings retained the majority of the synthesized farnesene. Two treatments to reduce stomatal aperture, dark exposure at midday, and abscisic acid treatment before daybreak, resulted in significantly reduced amounts of emitted and significantly increased amounts of in planta accumulating farnesene. Our results suggest that stomata not only play an important role in gas exchange for primary metabolism but also for indirect plant defences.


Asunto(s)
Glutamina/farmacología , Insectos/fisiología , Sesquiterpenos/metabolismo , Zea mays/metabolismo , Animales , Herbivoria , Transpiración de Plantas , Plantones/metabolismo , Zea mays/química
6.
Arch Virol ; 159(12): 3463-5, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25252813

RESUMEN

The 9573-nucleotide genome of a potyvirus was sequenced from a Coriandrum sativum plant from India with viral symptoms. On analysis, this virus was shown to have greater than 85 % nucleotide sequence identity to vanilla distortion mosaic virus (VDMV). Analysis of the putative coat protein sequence confirmed that this virus was in fact VDMV, with greater than 91 % amino acid sequence identity. The genome appears to encode a 3083-amino-acid polyprotein potentially cleaved into the 10 mature proteins expected in potyviruses. Phylogenetic analysis confirmed that VDMV is a distinct but ungrouped member of the genus Potyvirus.


Asunto(s)
Coriandrum/virología , Genoma Viral , Potyvirus/genética , ARN Viral/genética , Análisis de Secuencia de ADN , Análisis por Conglomerados , India , Datos de Secuencia Molecular , Filogenia , Enfermedades de las Plantas/virología , Poliproteínas/genética , Potyvirus/clasificación , Potyvirus/aislamiento & purificación , Homología de Secuencia de Aminoácido , Proteínas Virales/genética
7.
Sci Rep ; 4: 4155, 2014 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-24561664

RESUMEN

The dynamics of association between pathogens and vectors can strongly influence epidemiology. It has been proposed that wilt disease epidemics in cucurbit populations are sustained by persistent colonization of beetle vectors (Acalymma vittatum) by the bacterial phytopathogen Erwinia tracheiphila. We developed a qPCR method to quantify E. tracheiphila in whole beetles and frass and used it to assess pathogen acquisition and retention following variable exposure to infected plants. We found that (i) E. tracheiphila is present in frass in as little as three hours after feeding on infected plants and can be transmitted with no incubation period by vectors given brief exposure to infected plants, but also by persistently colonized vectors several weeks following exposure; (ii) duration of exposure influences rates of long-term colonization; (iii) frass infectivity (assessed via inoculation experiments) reflects bacterial levels in frass samples across time; and (iv) vectors rarely clear E. tracheiphila infections, but suffer no apparent loss of fitness. These results describe a pattern conducive to the effective maintenance of E. tracheiphila within cucurbit populations.


Asunto(s)
Vectores Artrópodos/microbiología , Escarabajos/microbiología , Enfermedades de las Plantas/microbiología , Animales , Cucurbita/microbiología , Cucurbita/parasitología , Erwinia/genética , Erwinia/aislamiento & purificación , Erwinia/fisiología , Interacciones Huésped-Patógeno , Hojas de la Planta/microbiología , Hojas de la Planta/parasitología , ARN Ribosómico 18S/metabolismo
8.
Arch Virol ; 159(4): 811-5, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24122155

RESUMEN

The complete nucleotide sequences of RNA 1 and RNA 2 of the nepovirus potato black ringspot virus (PBRSV) from two different isolates were determined, as well as partial sequences from two additional isolates. RNA1 is 7,579-7,598 nucleotides long and contains one single open reading frame (ORF), which is translated into a large polyprotein with 2,325 amino acids and a molecular weight of 257 kDa. The complete sequence of RNA2 ranges from 3857 to 3918 nt between the different isolates. It encodes a polyprotein of 1079-1082 amino acids with a molecular weight of 120 kDa. Sequence comparison using the Pro-Pol region and CP showed that all four isolates formed two distinct groups, corresponding to potato and arracacha, that were closely related to each other and also to tobacco ringspot virus (TRSV). Comparing our data to those obtained with other nepoviruses, our results confirm that PBRSV belongs to a distinct species and is a member of subgroup A in the genus Nepovirus based on its RNA2 size, genome organization, and nucleotide sequence.


Asunto(s)
Genoma Viral , Nepovirus/clasificación , Nepovirus/genética , ARN Viral/genética , Análisis de Secuencia de ADN , Análisis por Conglomerados , Datos de Secuencia Molecular , Peso Molecular , Nepovirus/aislamiento & purificación , Sistemas de Lectura Abierta , Filogenia , Homología de Secuencia , Solanum tuberosum/virología , Proteínas Virales/química , Proteínas Virales/genética
9.
Arch Virol ; 159(2): 385-8, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24005374

RESUMEN

This study reports the first complete genome sequence of Piper yellow mottle virus (PYMoV, KC808712) identified in black pepper. The genome is 7,622 nucleotides long, possessing four open reading frames (ORFs). ORF1, ORF2 and ORF4 of PYMoV are reported as hypothetical proteins of unknown function with a predicted molecular mass of 15.7, 17.1 and 17.9 kDa, respectively. ORF3 of PYMoV encodes a polyprotein of 218.6 kDa and consists of a viral movement protein (MP), trimeric dUTPase, zinc finger, retropepsin, RT-LTR, and RNAse H. Detailed PYMoV genome analysis confirmed that it is a member of the family Caulimoviridae, genus Badnavirus. Fragments of two additional novel sequences resembling those found in members of the family Caulimoviridae were also identified in the black pepper sample, and the viruses from which they were derived were tentatively named Piper DNA virus 1 and 2.


Asunto(s)
Badnavirus/genética , ADN Viral/química , ADN Viral/genética , Genoma Viral , Badnavirus/aislamiento & purificación , Datos de Secuencia Molecular , Peso Molecular , Sistemas de Lectura Abierta , Piper nigrum/virología , Análisis de Secuencia de ADN , Proteínas Virales/química , Proteínas Virales/genética
10.
J Virol Methods ; 191(2): 148-54, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22820076

RESUMEN

The causal agents of cassava brown streak disease have recently been identified as Cassava brown streak virus (CBSV) and Ugandan cassava brown streak virus (UCBSV). Primers have been developed for rapid detection of these viruses by reverse transcription loop-mediated isothermal amplification (RT-LAMP). Performance of the RT-LAMP assays compared favourably with published RT-PCR and real-time RT-PCR methods. Furthermore, amplification by RT-LAMP is completed in 40 min and does not require thermal cycling equipment. Modification of the RT-LAMP reactions to use labelled primers allowed rapid detection of amplification products using lateral flow devices containing antibodies specific to the incorporated labels, avoiding the need for fluorescence detection or gel electrophoresis.


Asunto(s)
Manihot/virología , Técnicas de Amplificación de Ácido Nucleico/métodos , Enfermedades de las Plantas/virología , Potyviridae/aislamiento & purificación , Virología/métodos , Cartilla de ADN/genética , Factores de Tiempo
11.
Arch Virol ; 158(4): 909-13, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23192172

RESUMEN

The complete genome sequences of RNA1 and RNA2 of the oca strain of the potato virus arracacha virus B were determined using next-generation sequencing. The RNA1 molecule is predicted to encode a 259-kDa polyprotein with homology to proteins of the cheraviruses apple latent spherical virus (ALSV) and cherry rasp leaf virus (CRLV). The RNA2 molecule is predicted to encode a 102-kDa polyprotein which also has homology to the corresponding protein of ALSV and, to a lesser degree, CRLV (30 % for RNA1, 24 % for RNA2). Detailed analysis of the genome sequence confirms that AVB is a distinct member of the genus Cheravirus.


Asunto(s)
Genoma Viral , Virus de Plantas/genética , Virus ARN/genética , Secuencia de Aminoácidos , Secuencia de Bases , Regulación Viral de la Expresión Génica/fisiología , Datos de Secuencia Molecular , Filogenia , Virus de Plantas/clasificación , Poliproteínas/genética , Poliproteínas/metabolismo , Virus ARN/clasificación , ARN Viral/genética , ARN Viral/metabolismo , Proteínas Virales/genética , Proteínas Virales/metabolismo
12.
Arch Virol ; 155(9): 1515-8, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20495988

RESUMEN

Canna yellow streak virus (Potyvirus, Potyviridae) was sequenced using the novel method of next-generation pyrosequencing. The complete genome was found to be 9,502 nucleotides excluding the poly-A tail with a predicted genome organisation typical for a member of the genus Potyvirus. As with other potyviruses that infect monocotyledons, some of the predicted cleavage sites of the polyprotein genome were unusual, such as a glutamic acid/threonine (E/T) between the CI and 6K2 proteins and a glutamic acid/aspartic acid (E/D) between the NIa and NIb proteins. Evidence of the presence of endogenous pararetroviruses in the canna genome was found from the large number of sequences obtained with this method.


Asunto(s)
Genoma Viral , Potyvirus/genética , Secuencia de Bases , Cannabaceae/virología , Datos de Secuencia Molecular , Filogenia , Enfermedades de las Plantas/virología , Potyvirus/clasificación , Potyvirus/aislamiento & purificación
13.
Environ Entomol ; 39(1): 140-8, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20146850

RESUMEN

Cucumber beetles, Acalymma vittatum (F.) and Diabrotica undecipunctata howardi (Barber), are specialist herbivores of cucurbits and the vector of Erwinia tracheiphila (E.F. Smith) Holland, the causative agent of wilt disease. Cucumber beetles transmit E. tracheiphila when infected frass falls onto leaf wounds at the site of beetle feeding. We show that E. tracheiphila also can be transmitted via the floral nectaries of Cucurbita pepo ssp. texana L. Andres (Texas gourd). Under field conditions, we found that beetles aggregate in flowers in the late morning, that these beetles chew the anther filaments that cover the nectaries in male flowers thereby exposing the nectary, and that beetle frass accumulates on the nectary. We use real-time polymerase chain reaction to show that most of the flowers produced during the late summer possess beetle frass containing E. tracheiphila. Greenhouse experiments, in which cultures of E. tracheiphila are deposited onto floral nectaries, show that Texas gourds can contract wilt disease through the floral nectaries. Finally, we use green fluorescent protein-transformed E. tracheiphila to document the movement of E. tracheiphila through the nectary into the xylem of the pedicel before the abscission of the flower. Together, these data show that E. tracheiphila can be transmitted through infected frass that falls on or near the floral nectaries. We hypothesize that the concentration of frass from many beetles in the flowers increases both exposure to and the concentration of E. tracheiphila and plays a major role in the dynamics of wilt disease in both wild populations and cultivated squash fields.


Asunto(s)
Escarabajos , Cucurbita/microbiología , Erwinia/fisiología , Flores/microbiología , Interacciones Huésped-Patógeno , Animales , Cucurbita/parasitología , Conducta Alimentaria , Flores/parasitología , Enfermedades de las Plantas/microbiología
14.
Arch Virol ; 155(3): 429-33, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20094895

RESUMEN

The complete genome sequence for an isolate of the Ugandan and Tanzanian strain types of Cassava brown streak virus have been determined using the novel approach of non-directed next generation sequencing. Comparison of the genome sequences revealed that CBSV is highly heterogeneous at the isolate level as well as the strain level. The isolate of the Ugandan strain was found to have a genome 9,070 nucleotides long coding for a polypeptide with 2,902 amino acid residues. The isolate of the Tanzanian strain was 9,008 nucleotides long and coded for a polypeptide with 2,916 amino acid residues. Nucleotide identity between the isolates across the genome was 76%, with protein encoding regions 57-77% and individual proteins had 65-91% amino acid similarity. In addition between the two strains four protein products (PIPO, CI, NIa-Vpg and coat protein) varied in size and an unusual HAM1-like protein, whilst of identical nucleotide length, was found to have the lowest homology. The implication of diversity of CBSV is discussed in the context of speciation, evolution, development of diagnostics, and breeding for resistance.


Asunto(s)
Enfermedades de las Plantas/virología , Potyviridae/genética , ARN Viral/genética , Análisis de Secuencia de ADN , Manihot/virología , Datos de Secuencia Molecular , Polimorfismo Genético , Potyviridae/aislamiento & purificación , Homología de Secuencia de Aminoácido , Homología de Secuencia de Ácido Nucleico , Sintenía , Tanzanía , Uganda
16.
Br J Cancer ; 92(8): 1493-8, 2005 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-15812556

RESUMEN

Angiogenesis is characterised by activation, migration and proliferation of endothelial cells and is central to the pathology of cancer, cardiovascular disease and chronic inflammation. Somatostatin is an inhibitory polypeptide that acts through five receptors (sst 1, 2, 3, 4, 5). Sst has previously been reported in endothelium, but their role remains obscure. Here, we report the expression of sst in human umbilical vein endothelial cells (HUVECs) in vitro, during proliferation and quiescence. A protocol for culturing proliferating and quiescent HUVECs was established, and verified by analysing cell cycle distribution in propidium-iodide-stained samples using flow cytometry. Sst mRNA was then quantified in nine proliferating and quiescent HUVEC lines using quantitative reverse transcriptase-polymerase chain reaction. Sst 2 and 5 were preferentially expressed in proliferating HUVECs. All samples were negative for sst 4. Sst 1 and 3 expression and cell cycle progression were unrelated. Immunostaining for sst 2 and 5 showed positivity in proliferating but not quiescent cells, confirming sst 2 and 5 protein expression. Inhibition of proliferating cells with somatostatin analogues Octreotide and SOM230, which have sst 5 activity, was found (Octreotide 10(-10)-10(-6) M: 48.5-70.2% inhibition; SOM230 10(-9)-10(-6) M: 44.9-65.4% inhibition) in a dose-dependent manner, suggesting that sst 5 may have functional activity in proliferation. Dynamic changes in sst 2 and 5 expression during the cell cycle and the inhibition of proliferation with specific analogues suggest that these receptors may have a role in angiogenesis.


Asunto(s)
Endotelio Vascular/metabolismo , Receptores de Somatostatina/biosíntesis , Somatostatina/análogos & derivados , Antineoplásicos Hormonales/farmacología , Ciclo Celular , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Relación Dosis-Respuesta a Droga , Células Endoteliales/efectos de los fármacos , Células Endoteliales/metabolismo , Endotelio Vascular/efectos de los fármacos , Citometría de Flujo , Humanos , Inmunohistoquímica , Neovascularización Patológica , Octreótido/farmacología , Receptores de Somatostatina/efectos de los fármacos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Somatostatina/farmacología , Venas Umbilicales/citología , Venas Umbilicales/metabolismo
17.
Infection ; 31(5): 353-8, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-14556063

RESUMEN

An 11-year-old patient with anamnestic fever for 3 days and signs of upper respiratory tract infection underwent fulminant Staphylococcus aureus pneumonia with concomitant agranulocytosis. From autopsia influenza B virus and parvovirus B19 were detected by nucleic acid amplification technique (NAT). Specific IgG but no IgM points to preexisting parvovirus B19 infection. Whether in this case agranulocytosis can be interpreted as early manifestation of reactivated parvovirus B19 infection is under discussion. Therefore, parvovirus B19 could have provoked a foudroyant course of influenza B pneumonia which was superinfected with S. aureus.


Asunto(s)
Agranulocitosis/diagnóstico , Virus de la Influenza B/aislamiento & purificación , Infecciones por Parvoviridae/diagnóstico , Parvovirus B19 Humano/aislamiento & purificación , Neumonía Viral/diagnóstico , Sobreinfección/microbiología , Agranulocitosis/complicaciones , Agranulocitosis/terapia , Autopsia , Niño , Terapia Combinada , Progresión de la Enfermedad , Resultado Fatal , Humanos , Pulmón/patología , Masculino , Infecciones por Parvoviridae/complicaciones , Neumonía Viral/complicaciones , Neumonía Viral/terapia , Insuficiencia Respiratoria/diagnóstico , Insuficiencia Respiratoria/etiología , Índice de Severidad de la Enfermedad , Sobreinfección/complicaciones , Sobreinfección/terapia
18.
Cardiovasc Surg ; 11(1): 52-60, 2003 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-12543573

RESUMEN

Statins block de novo synthesis of cholesterol by inhibiting the enzyme, HMG CoA reductase. The product of this reaction, mevalonic acid, is also a precursor of isoprenoids, molecules required for the activation of signaling G-proteins, such as Ras. Signal transduction pathways involving Ras are important for cell survival and this may be why statins induce apoptotic death of several cell types. Given that statins are used to treat vascular disease, surprisingly no studies have been conducted on vascular endothelial cells. Here we show that fluvastatin (FS), at concentrations from 1-2 microM, blocks growth and induces apoptosis of the endothelial cell line, EA.hy 926. Considerable redundancy is known to exist in cell signaling and in vivo toxicity of FS might be prevented by other signaling pathways, like those activated by adrenal or sex steroids. RT-PCR analysis revealed the expression of the androgen and glucocorticoid receptor in EA.hy 926 cells. Although the androgen, dihydrotestesterone (DHT) had no effect, the glucocorticoid, dexamethasone (Dex), blocked FS-induced apoptosis. Cell cycle analysis revealed that 24 h exposure to FS prevented cells from leaving G(1) and 24-48 h later a marked sub-G(1) peak was observed. Dex was able to reduce the sub-G(1) peak, but it failed to block accumulation of cells in G(1), indicating that it's effect was specific for blockade of apoptosis, and not specific to an effect on FS alone. This study strongly suggests that glucocorticoids have a role to play in preventing vascular injury and they may provide the reason why statins are not inherently toxic to vascular endothelial cells, in vivo.


Asunto(s)
Anticolesterolemiantes/farmacología , Apoptosis/efectos de los fármacos , Endotelio Vascular/efectos de los fármacos , Ácidos Grasos Monoinsaturados/farmacología , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Indoles/farmacología , Ciclo Celular/efectos de los fármacos , Línea Celular , Dexametasona/farmacología , Relación Dosis-Respuesta a Droga , Endotelio Vascular/citología , Citometría de Flujo , Fluvastatina , Glucocorticoides/farmacología , Humanos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transducción de Señal/efectos de los fármacos
19.
Actual. pediátr ; 12(3): 92-105, sept. 2002.
Artículo en Español | LILACS | ID: lil-347543

RESUMEN

El síndrome de respuesta inflamatoria sistémica (SIRS)representa la respuesta del huésped a la infección o al daño tisular difuso y se caracteriza por la liberación de varios mediadores proinflamatorios y antiinflamatorios. Si la respuesta es excesiva hay compromiso sistémico que termina en daño de órganos. Este conocimiento crea una función potencial de citoquinas en el diagnóstico temprano de infección y en el desarrollo de estrategias terapeúticas dirigidas para atenuar la respuesta inflamatoria sistémica y de esa forma mejorar el desenlace clínico


Asunto(s)
Humanos , Recién Nacido , Recién Nacido , Síndrome de Respuesta Inflamatoria Sistémica
20.
J Endocrinol ; 174(1): 7-16, 2002 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12098658

RESUMEN

Statins block de novo synthesis of cholesterol by inhibiting the enzyme, HMG CoA reductase. The product of this reaction, mevalonic acid, is also a precursor of isoprenoids, molecules required for the activation of signalling G-proteins, such as Ras. Signal transduction pathways involving Ras are important for cell survival and this may be why statins induce apoptotic death of several cell types. Given that statins are used to treat vascular disease, it is surprising that no studies have been conducted on vascular endothelial cells. For this reason, we have tested the effect of fluvastatin (FS) on the endothelial cell line EA.hy 926. Here we show that FS, at concentrations from 1 to 2 microM, blocks growth and induces apoptosis of the endothelial cell line, EA.hy 926. As considerable redundancy exists in cell signalling pathways for cell survival, toxicity of FS under more physiological conditions might be prevented by pathways that do not require Ras, such as those activated by adrenal or sex steroids. To test this hypothesis, first RT-PCR analysis was performed for nuclear receptor mRNA expression. This revealed the presence of mRNA for the androgen receptor (AR) and glucocorticoid receptor (GR). The effect of the AR agonist, dihydrotestosterone (DHT), and the GR agonist, dexamethasone (Dex), was then tested. Whilst DHT (100 nM) had no effect on FS-induced cell death, Dex (1 microM) blocked FS-induced apoptosis. Cell cycle analysis revealed that 24 h exposure to FS prevented cells from leaving G(1) and 24-48 h later a marked sub-G(1) peak was observed. Dex was able to reduce the sub-G(1) peak, but it failed to reduce accumulation of cells in G(1). Further studies revealed that, in addition to blocking FS-induced apoptosis, Dex was able to block apoptosis of EA.hy 926 cells induced by serum deprivation, tumour necrosis factor-alpha, oxidants, DNA damage and mitochondrial disruption. This study strongly suggests that glucocorticoids have a role to play in preventing vascular injury and they may provide a reason why statins are apparently not toxic to vascular endothelial cells in vivo.


Asunto(s)
Anticolesterolemiantes/farmacología , Apoptosis/efectos de los fármacos , Dexametasona/farmacología , Endotelio Vascular/citología , Células Epiteliales/citología , Ácidos Grasos Monoinsaturados/farmacología , Indoles/farmacología , Receptores de Glucocorticoides/antagonistas & inhibidores , Antagonistas de Receptores Androgénicos , Recuento de Células , Células Cultivadas , Dihidrotestosterona/farmacología , Relación Dosis-Respuesta a Droga , Combinación de Medicamentos , Endotelio Vascular/efectos de los fármacos , Células Epiteliales/efectos de los fármacos , Citometría de Flujo/métodos , Fluvastatina , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/metabolismo , Ácido Mevalónico/farmacología , ARN Mensajero/análisis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
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