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1.
Vet Res Commun ; 41(3): 233-239, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28429153

RESUMEN

It is widely accepted that mature sperm contains RNA. The first hypothesis was that sperm RNAs have no functions of their own but are simply residues of spermatogenesis reflecting the events that occurred during their formation in the testes. More recently new discoveries have essentially expanded these views, showing that sperm mRNAs constitute a population of stable full-length transcripts, many of which are selectively retained during spermatogenesis and delivered to oocytes contributing to early embryo development. It is well known that semen quality can be influenced by occasional physical stress, infection, and variation in temperature and the definition of new markers for evaluation of semen could offer knowledge about the fertility potential of a semen sample. The aim of the present study was to evaluate the presence and the relative quantity of transcripts and protein of heat shock protein 70 (HSP70), 90 (HSP90) and clusterin (CLU) in Percoll-selected spermatozoa collected from seven adult boars of proven fertility routinely employed for artificial insemination. Our results showed the presence of HSP70, HSP90 and CLU transcripts with different level of expression: high for HSPs and low for CLU transcripts. The transcript level of both HSPs are similar among selected spermatozoa derived from high quality sperm with the exception of one boar that showed a reduced content of HSP70 and HSP90 mRNA together with a lower semen quality. At protein level, both HSPs were detected with similar amount among all seven boars whilst no band was evidenced for CLU protein.


Asunto(s)
Clusterina/análisis , Proteínas de Choque Térmico/análisis , Inseminación Artificial/veterinaria , Espermatozoides/química , Animales , Western Blotting/veterinaria , Proteínas HSP70 de Choque Térmico/análisis , Proteínas HSP90 de Choque Térmico/análisis , Masculino , ARN/aislamiento & purificación , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinaria , Análisis de Semen/veterinaria , Motilidad Espermática , Espermatozoides/metabolismo , Porcinos
2.
Vet Pathol ; 53(4): 773-80, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-26993784

RESUMEN

Canine liposarcoma is an uncommon soft tissue sarcoma usually arising in the subcutis. While liposarcoma classification in dogs is based solely on histology, in humans it depends on the detection of genetic abnormalities that can lead to specific protein overexpression. This study is an immunohistochemical evaluation of MDM2 and CDK4 expression in canine liposarcoma designed to assess the correlation of these proteins with histologic type, grade, mitotic index and Ki67 labeling index and evaluate their utility in improving tumor classification. Fifty-three liposarcomas were retrospectively collected: 24 were well differentiated liposarcomas (WDL), 16 of which expressed MDM2 and 21 CDK4; 7 were myxoid liposarcomas (ML), 1 of which expressed MDM2 and 5 expressed CDK4; 18 were pleomorphic liposarcomas (PL), all were MDM2 negative and 12 expressed CDK4. Four tumors were morphologically consistent with dedifferentiated liposarcoma (DDL) a subtype described only in humans: 3 expressed MDM2 and 4 expressed CDK4. MDM2 expression correlated with histotype (highly expressed in WDL and DDL) and grade (highly expressed in grade 1 tumors). Histotype correlated with the Ki67 labeling index (lowest in WDL and highest in DDL). A revised classification, considering MDM2 expression, allowed 8 WDL to be reclassified as PL and correlated significantly with mitotic and Ki67 labeling index (both significantly lower in WDL and progressively higher in ML and DDL). These results partially parallel data reported for human liposarcomas, suggesting that WDL and DDL are distinct neoplastic entities characterized by MDM2 expression, which may represent a useful diagnostic and potentially prognostic marker for canine liposarcoma.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Quinasa 4 Dependiente de la Ciclina/metabolismo , Enfermedades de los Perros/diagnóstico , Liposarcoma/veterinaria , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Animales , Enfermedades de los Perros/metabolismo , Enfermedades de los Perros/patología , Perros , Femenino , Inmunohistoquímica/veterinaria , Liposarcoma/diagnóstico , Liposarcoma/metabolismo , Liposarcoma/patología , Masculino , Clasificación del Tumor/veterinaria , Estudios Retrospectivos
3.
Artículo en Inglés | MEDLINE | ID: mdl-26256121

RESUMEN

Tributyltin (TBT), is a man-made pollutants, known to accumulate along the food chain, acting as an endocrine disruptor in marine organisms, with toxic and adverse effects in many tissues including vascular system. Based on the absence of specific studies of TBT effects on endothelial cells, we aimed to evaluate the toxicity of TBT on primary culture of porcine aortic endothelial cells (pAECs), pig being an excellent model to study human cardiovascular disease. pAECs were exposed for 24h to TBT (100, 250, 500, 750 and 1000nM) showing a dose dependent decrease in cell viability through both apoptosis and necrosis. Moreover the ability of TBT (100 and 500nM) to influence endothelial gene expression was investigated at 1, 7 and 15h of treatment. Gene expression of tight junction molecules, occludin (OCLN) and tight junction protein-1 (ZO-1) was reduced while monocyte adhesion and adhesion molecules ICAM-1 and VCAM-1 (intercellular adhesion molecule-1 and vascular cell adhesion molecule-1) levels increased significantly at 1h. IL-6 and estrogen receptors 1 and 2 (ESR-1 and ESR-2) mRNAs, after a transient decrease, reached the maximum levels after 15h of exposure. Finally, we demonstrated that TBT altered endothelial functionality greatly increasing monocyte adhesion. These findings indicate that TBT deeply alters endothelial profile, disrupting their structure and interfering with their ability to interact with molecules and other cells.


Asunto(s)
Células Endoteliales/efectos de los fármacos , Compuestos de Trialquiltina/toxicidad , Animales , Apoptosis/efectos de los fármacos , Adhesión Celular , Moléculas de Adhesión Celular/genética , Moléculas de Adhesión Celular/metabolismo , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Técnicas de Cocultivo , Relación Dosis-Respuesta a Droga , Células Endoteliales/metabolismo , Células Endoteliales/patología , Regulación de la Expresión Génica , Monocitos/efectos de los fármacos , Monocitos/metabolismo , Necrosis , Porcinos , Proteínas de Uniones Estrechas/genética , Proteínas de Uniones Estrechas/metabolismo , Uniones Estrechas/efectos de los fármacos , Uniones Estrechas/metabolismo , Uniones Estrechas/patología , Factores de Tiempo
4.
Infection ; 42(5): 859-67, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24973981

RESUMEN

PURPOSE: Migrants account for approximately 8.7% of the resident population in Italy. The immigration status deeply influences access to prevention and care, thus contributing to increase the burden of HIV/AIDS among such a fragile category. The aim of this study was to investigate socio-demographic and baseline clinical and immunological features of HIV-infected migrants, as compared to Italians. METHODS: We retrospectively analysed data for all the 1,611 HIV-infected migrant patients and a random sample of 4,230 HIV-infected Italian patients aged 18 or older who first accessed nine Italian clinical centres in 2000-2010 and were followed up at least 1 year. Differences in baseline characteristics between migrants and Italians were evaluated in univariate analysis, while factors associated with late presentation were evaluated in multivariate analysis using logistic regression models. RESULTS: The baseline profile differs between the HIV-infected migrant and Italian patients, substantially reflecting what reported by current statistics in terms of gender, age, risk category as well as clinical features. Late presenters were more frequent among migrants as compared to Italians (53.0 vs 45.8%; adjusted odds ratio [(AOR) = 1.55, 95% confidence interval (CI) 1.34-1.78]. Other factors associated with late presentation included increasing age, as well as undocumented legal status among foreign-born subjects (AOR = 1.41, 95% CI 0.97-2.04), though of borderline significance. CONCLUSIONS: Late presentation still represents a relevant problem despite the advances in the management of HIV infection. More efforts are needed to allow early diagnosis and access to care among the most vulnerable, such as undocumented foreign-born subjects in a country where migration flows are on the rise.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/epidemiología , Infecciones por VIH/epidemiología , Migrantes , Síndrome de Inmunodeficiencia Adquirida/virología , Adolescente , Adulto , Femenino , Infecciones por VIH/virología , Humanos , Italia/epidemiología , Modelos Logísticos , Masculino , Oportunidad Relativa , Prevalencia , Estudios Retrospectivos , Adulto Joven
5.
Theriogenology ; 82(1): 144-51.e1, 2014 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-24751294

RESUMEN

During the transit in the female genital tract, spermatozoa are exposed to an environment that varies in composition from the vagina to the oviduct. Because G proteins, α-gustducin and α-transducin, are accepted as markers of chemosensitive cells, this study was aimed at assessing whether these proteins are expressed in boar germ cells. Ejaculated sperm extracts were analyzed by Western blot, and indirect immunofluorescence was performed on testis sections, smears of epididymal and ejaculated spermatozoa, sperm cells after in vitro induction of capacitation and acrosome reaction (IVAR), and in sperm cells bound to zona pellucida during IVF. Based on immunoblot results, both G proteins are present in boar sperm. In the testicular tissue sections, α-gustducin and α-transducin positivity was recorded in the germinal cells near the tubular lumen, whereas no positive signal was evident in spermatogonia located in the outer region of the seminiferous tubules. α-Gustducin expression in epididymal and ejaculated spermatozoa was mainly detectable in both the acrosome and the principal piece of the tail, whereas α-transducin was confined to the acrosome and the midpiece. No changes after in vitro induction of capacitation and IVAR were observed, except for the disappearance of acrosomal positivity in reacted spermatozoa. In sperm bound to zona pellucida, the G protein signal was congruent with that observed in IVAR cells. To the best of our knowledge, this is the first description of α-transducin in mammalian sperm and the first description of α-gustducin in boar sperm. Further studies are needed to clarify the possible role of these G proteins in sperm physiology.


Asunto(s)
Proteínas de Unión al GTP/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Espermatozoides/metabolismo , Porcinos/metabolismo , Transducina/metabolismo , Animales , Western Blotting , Inmunohistoquímica , Masculino , Interacciones Espermatozoide-Óvulo
6.
Chem Soc Rev ; 42(5): 2100-29, 2013 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-23247337

RESUMEN

In 1861 Thomas Graham gave birth to a new field of science, today known as colloid science. Nowadays, the notion "colloid" is often used referring to systems consisting of two immiscible phases, one of which is finely dispersed into the other. Research on colloids deals mostly with sols (solids dispersed in a liquid), emulsions (liquids dispersed in liquid), and foams (gas dispersed in a liquid). Because the dispersed particles are small, there is a lot of interface per unit mass. Not surprisingly, therefore, the properties of the interface have often a decisive effect on the behaviour of colloids. Water-air interfaces have a special relevance in this field: many water-insoluble molecules can be spread on water and, given the right spreading conditions and enough available surface area, their spreading proceeds until a monolayer (a one-molecule thick layer) eventually remains. Several 2D phases have been identified for such monolayers, like "gas", "liquid expanded", "liquid condensed", and "solid". The central question of this review is whether these 2D phases can also exist as colloidal systems, and what stabilizes the dispersed state in such systems. We shall present several systems capable of yielding 2D phase separation, from those based on either natural or fluorinated amphiphiles, to polymer-based ones. We shall seek for analogies in 3D and we shall try to clarify if the lines between these 2D objects play a similar role as the interfaces between 3D colloidal systems. In particular, we shall consider the special role of molecules that tend to accumulate at the phase boundaries, that is, at the contact lines, which will therefore be denoted "line-actants" (molecules that adsorb at a 1D interface, separating two 2D colloidal entities), by analogy to the term "surfactant" (which indicates a molecule that adsorbs at a 2D interface separating two 3D colloidal entities).


Asunto(s)
Coloides/química , Alcoholes/química , Alquenos/química , Emulsiones/química , Ácidos Grasos/química , Flúor/química , Polímeros/química , Propiedades de Superficie , Tensoactivos/química
7.
Langmuir ; 28(13): 5614-21, 2012 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-22428956

RESUMEN

We analyze the possibility of polymer blends undergoing phase separation in two dimensions. To this end, we investigate a model system consisting of water-supported Langmuir monolayers, obtained from binary polyalkyl-methacrylate mixtures (PXMA, where X stands for any of the type of ester side groups used: M, methyl-; E, ethyl-; B, butyl-; H, hexyl-; O, octyl-; L, lauryl-methacrylate), by means of self consistent field (SCF) calculations. In particular, we address the conditions which determine demixing and phase separation in the two-dimensional system, showing that a sufficient chain length mismatch in the ester side group moieties is able to drive the polymer demixing. When the difference in length of the alkyl chain of the ester moieties on the two types of polymers is progressively reduced, from 11 carbon atoms (PMMA/PLMA) to 4 carbons only (POMA/PLMA), the demixing tendency is also reduced. The polymer/subphase interactions affect more the distribution of the polymer coils in the POMA/PLMA blend monolayer. Mixing of the two polymers is observed, but also a partial layering along the vertical direction. We also add, to a PMMA/PLMA blended monolayer, a third component, namely, a symmetrical diblock copolymer of the type PLMA-b-PMMA. We observe adsorption of the diblock copolymer exclusively at the contact line between the two homopolymer domains, and a concomitant lowering of the line tension. The line tension varies with the chemical potential of the diblock copolymer according to Gibbs' law, which demonstrates that PLMA-b-PMMA can act as a "lineactant" (the equivalent of a surfactant in two-dimensional systems) in the binary demixed PMMA/PLMA Langmuir monolayer.

8.
Langmuir ; 27(6): 2501-8, 2011 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-21299222

RESUMEN

We report a system consisting of a mixed Langmuir monolayer, made of water-insoluble, spreadable, fluid-like polymers polydimethylsiloxane (PDMS) and polymethylmethacrylate (PMMA) with a minority P(DMS-b-MMA) copolymer. We have performed both Langmuir trough pressure/area isotherm measurements and Brewster angle microscopy (BAM) observations and complement the experiments with molecularly detailed self-consistent field (SCF) calculations. PDMS undergoes a layering transition that is difficult to detect by BAM. Addition of PMMA gives contrast in BAM, now showing a two-phase system: if this would consist of separate two-dimensional (2D) PMMA and PDMS phases, a PDMS-PMMA diblock should accumulate at the phase boundary. However, the diblock copolymer of PDMS-PMMA failed to show the expected "lineactant" behavior, i.e., failed to accumulate at the phase boundary. The calculations point to a nontrivial arrangement of the polymer chains at the interface: in mixtures of the two homopolymers, in a rather wide composition ratio, we find a vertical (with respect to the air/water interfacial plane) configuration, with PMMA sitting preferably at the PDMS/water interface of the thicker PDMS film, during the PDMS layering phase transition. This also explains why the diblock copolymer is not a lineactant. Both PMMA and P(DMS-b-MMA) are depleted from the thin-thick PDMS film interface, and the line tension between the phases is, consequently, increased, in the binary mixtures as well as in the ternary ones.

9.
Epidemiol Infect ; 139(11): 1740-9, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21226988

RESUMEN

We retrospectively studied patients diagnosed with P. aeruginosa bloodstream infections (BSIs) in two Italian university hospitals. Risk factors for the isolation of multidrug-resistant (MDR) or non-MDR P. aeruginosa in blood cultures were identified by a case-case-control study, and a cohort study evaluated the clinical outcomes of such infections. We identified 106 patients with P. aeruginosa BSI over the 2-year study period; 40 cases with MDR P. aeruginosa and 66 cases with non-MDR P. aeruginosa were compared to 212 controls. Independent risk factors for the isolation of MDR P. aeruginosa were: presence of central venous catheter (CVC), previous antibiotic therapy, and corticosteroid therapy. Independent risk factors for non-MDR P. aeruginosa were: previous BSI, neutrophil count <500/mm3, urinary catheterization, and presence of CVC. The 21-day mortality rate of all patients was 33·9%. The variables independently associated with 21-day mortality were presentation with septic shock, infection due to MDR P. aeruginosa, and inadequate initial antimicrobial therapy.


Asunto(s)
Bacteriemia/epidemiología , Bacteriemia/microbiología , Farmacorresistencia Bacteriana Múltiple , Infecciones por Pseudomonas/epidemiología , Infecciones por Pseudomonas/microbiología , Pseudomonas aeruginosa/aislamiento & purificación , Adulto , Anciano , Anciano de 80 o más Años , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Bacteriemia/tratamiento farmacológico , Infecciones Relacionadas con Catéteres/tratamiento farmacológico , Infecciones Relacionadas con Catéteres/epidemiología , Infecciones Relacionadas con Catéteres/microbiología , Infección Hospitalaria/tratamiento farmacológico , Infección Hospitalaria/epidemiología , Infección Hospitalaria/microbiología , Femenino , Hospitales Universitarios/estadística & datos numéricos , Humanos , Incidencia , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Infecciones por Pseudomonas/tratamiento farmacológico , Pseudomonas aeruginosa/efectos de los fármacos , Estudios Retrospectivos , Factores de Riesgo
10.
J Comp Neurol ; 518(19): 4046-66, 2010 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-20737599

RESUMEN

The distribution and chemical phenotypes of sympathetic and dorsal root ganglion (DRG) neurons innervating the equine ileocecal junction (ICJ) were studied by combining retrograde tracing and immunohistochemistry. Immunoreactivity (IR) for tyrosine hydroxylase (TH), dopamine beta-hydroxylase (DBH), neuronal nitric oxide synthase (nNOS), calcitonin gene-related peptide (CGRP), substance P (SP), and neuropeptide Y (NPY) was investigated. Sympathetic neurons projecting to the ICJ were distributed within the celiac (CG), cranial mesenteric (CranMG), and caudal mesenteric (CaudMG) ganglia, as well as in the last ganglia of the thoracic sympathetic chain and in the splanchnic ganglia. In the CG and CranMG 91 +/- 8% and 93 +/- 12% of the neurons innervating the ICJ expressed TH- and DBH-IR, respectively. In the CaudMG 90 +/- 15% and 94 +/- 5% of ICJ innervating neurons were TH- and DBH-IR, respectively. Sympathetic (TH-IR) fibers innervated the myenteric and submucosal ganglia, ileal blood vessels, and the muscle layers. They were more concentrated at the ICJ level and were also seen encircling myenteric plexus (MP) and submucosal plexus (SMP) descending neurons that were retrogradely labeled from the ICJ. Among the few retrogradely labeled DRG neurons, nNOS-, CGRP-, and SP-IR nerve cells were observed. Dense networks of CGRP-, nNOS-, and SP-IR varicosities were seen around retrogradely labeled prevertebral ganglia neurons. The CGRP-IR fibers are probably the endings of neurons projecting from the intestine to the prevertebral ganglia. These findings indicate that this crucial region of the intestinal tract is strongly influenced by the sympathetic system and that sensory information of visceral origin influences the sympathetic control of the ICJ.


Asunto(s)
Ciego/inervación , Caballos/anatomía & histología , Íleon/inervación , Sistema Nervioso Simpático , Animales , Péptido Relacionado con Gen de Calcitonina/metabolismo , Dopamina beta-Hidroxilasa/metabolismo , Femenino , Colorantes Fluorescentes/metabolismo , Ganglios Espinales/citología , Inmunohistoquímica , Masculino , Fibras Nerviosas/metabolismo , Fibras Nerviosas/ultraestructura , Vías Nerviosas/anatomía & histología , Vías Nerviosas/metabolismo , Neuronas/citología , Neuronas/metabolismo , Neuropéptido Y/metabolismo , Óxido Nítrico Sintasa de Tipo I/metabolismo , Médula Espinal/citología , Médula Espinal/metabolismo , Sustancia P/metabolismo , Sistema Nervioso Simpático/anatomía & histología , Sistema Nervioso Simpático/fisiología , Tirosina 3-Monooxigenasa/metabolismo
11.
Gene Expr ; 14(6): 345-59, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20635576

RESUMEN

S100B is a Ca2+ binding protein mainly secreted by astrocytes in the vertebrate brain that is considered a multifunctional cytokine and/or a damage-associated molecular pattern (DAMP) protein and a marker of brain injury and neurodegeneration when measured in different body fluids. It has been widely shown that this protein can exert diverse effects in neural cultures depending on its concentration, having detrimental effects at micromolar concentrations. The molecular mechanisms underlying this effect are still largely unknown. This study attempts to delineate the genome-wide gene expression analysis of the events associated with exposure to micromolar concentration of S100B in a human neuroblastoma cell line. In this experimental condition cells undergo a severe perturbation of lipid homeostasis along with cell cycle arrest. These mechanisms might reasonably mediate some aspects of the S100B-related detrimental effects of S100B, although obvious differences between mature neurons and neuroblastoma cells have to be considered.


Asunto(s)
Ciclo Celular , Colesterol/metabolismo , Factores de Crecimiento Nervioso/genética , Neuroblastoma/genética , Proteínas S100/genética , Transcripción Genética , Perfilación de la Expresión Génica , Homeostasis , Humanos , Factores de Crecimiento Nervioso/metabolismo , Neuroblastoma/metabolismo , Análisis de Secuencia por Matrices de Oligonucleótidos , Subunidad beta de la Proteína de Unión al Calcio S100 , Proteínas S100/metabolismo , Células Tumorales Cultivadas
12.
Theriogenology ; 74(5): 741-8, 2010 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-20570336

RESUMEN

A routine use of boar sexed semen is far from being a reality due to many limiting factors among which is the long sorting time necessary to obtain the adequate number of sexed spermatozoa for artificial insemination and the high susceptibility to damages induced by cryopreservation. The aim of this study was to evaluate the modification induced by 24-26 h storage on sorted boar spermatozoa on the basis of their viability, acrosome status, Hsp70 presence, and in vitro fertilizing ability. The percentage of viable cells, according to SYBR green/PI staining, was negatively affected (P < 0.05) by sorting procedure. Moreover, liquid storage significantly (P < 0.05) reduced membrane integrity of sorted spermatozoa as compared to all the other groups. Neither sorting nor storage influenced the percentage of live cells with reacted acrosome, according to FITC-PNA/PI staining. Sorted samples, after 24-26 h storage, were characterized by an increase (P < 0.05) of sperm cells negative for Hsp70, as observed by immunofluorescence, and by a decrease (P < 0.05) in Hsp70 content, as evidenced by western blot. While sorting procedure did not adversely affect both penetration rate and total efficiency of fertilization, these parameters were negatively (P < 0.05) influenced by storage after sorting. In order to minimize damages that compromise fertility and function of sex-sorted boar spermatozoa, the mechanisms by which sorting and liquid storage cause these injures require further study.


Asunto(s)
Criopreservación/veterinaria , Preservación de Semen/veterinaria , Espermatozoides/fisiología , Porcinos , Acrosoma/fisiología , Animales , Western Blotting , Membrana Celular/fisiología , Membrana Celular/ultraestructura , Exocitosis , Fertilización/fisiología , Fertilización In Vitro/veterinaria , Proteínas HSP70 de Choque Térmico/metabolismo , Masculino , Análisis de Semen/veterinaria , Interacciones Espermatozoide-Óvulo , Espermatozoides/metabolismo , Espermatozoides/ultraestructura
13.
Langmuir ; 26(14): 11850-61, 2010 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-20572654

RESUMEN

Surface pressure isotherms at the air/water interface are reproduced for four different polymers, poly-L-lactic acid (PLLA), poly(dimethylsiloxane) (PDMS), poly(methyl methacrylate) (PMMA), and poly(isobutylene) (PiB). The polymers have the common property that they do not dissolve in water. The four isotherms differ strongly. To unravel the underlying details that are causing these differences, we have performed molecularly detailed self-consistent field (SCF) modeling. We describe the polymers on a united atom level, taking the side groups on the monomer level into account. In line with experiments, we find that PiB spreads in a monolayer which smoothly thickens already at a very low surface pressure. PMMA has an autophobic behavior: a PMMA liquid does not spread on top of the monolayer of PMMA at the air/water interface. A thicker PMMA layer only forms after the collapse of the film at a relatively high pressure. The isotherm of PDMS has regions with extreme compressibility which are linked to a layering transition. PLLA wets the water surface and spreads homogeneously at larger areas per monomer. The classical SCF approach features only short-range nearest-neighbor interactions. For the correct positioning of the layering and for the thickening of the polymer films, we account for a power-law van der Waals contribution in the model. Two-gradient SCF computations are performed to model the interface between two coexistent PDMS films at the layering transition, and an estimation of the length of their interfacial contact is obtained, together with the associated line tension value.

14.
Vet Res Commun ; 34 Suppl 1: S21-4, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20437271

RESUMEN

Endothelin (ET)-1 is a potent vasoconstrictor peptide involved in the derangement of respiratory mechanics during endotoxic shock. We measured the kinetics of pulmonary mRNA expression of the key components of the ET system [i.e., ET-1, ET-converting enzyme (ECE), and ETA and ETB receptors] by quantitative real-time reverse transcriptase-polymerase chain reaction in a swine model of endotoxic shock (0, 1, 2, 3, and 4 h of continuous LPS infusion at 40 microg/kg/hour; sham group, 4 hour saline infusion). A significant increase in mRNA expression levels was observed for ET-1 in LPS-treated piglets; the increase began as early as 1 hour. In contrast, no significant variations were observed for the ECE, ETA, or ETB genes. Small gene expression differences observed with respect to our previous results suggest a possible effect of the anesthesia or surgical protocol on ET system regulation.


Asunto(s)
Lipopolisacáridos/toxicidad , Pulmón/metabolismo , Choque Séptico/veterinaria , Enfermedades de los Porcinos/inducido químicamente , Animales , Ácido Aspártico Endopeptidasas/genética , Ácido Aspártico Endopeptidasas/metabolismo , Relación Dosis-Respuesta a Droga , Enzimas Convertidoras de Endotelina , Endotelinas/genética , Endotelinas/metabolismo , Femenino , Regulación de la Expresión Génica , Lipopolisacáridos/administración & dosificación , Masculino , Metaloendopeptidasas/genética , Metaloendopeptidasas/metabolismo , Receptor de Endotelina A/genética , Receptor de Endotelina A/metabolismo , Receptor de Endotelina B/genética , Receptor de Endotelina B/metabolismo , Choque Séptico/metabolismo , Porcinos , Enfermedades de los Porcinos/metabolismo
16.
Theriogenology ; 72(9): 1163-70, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19767086

RESUMEN

A simple and efficient method for producing multitransgenic animals is required for medical and veterinary applications. Sperm-mediated gene transfer (SMGT) is an effective method for introducing multiple genes into pigs (Sus, Sus scrofa). The major benefits of this technique are the high efficiency, low cost, and ease of use compared with that of other methods: Sperm-mediated gene transfer does not require embryo handling or expensive equipment. The aim of this study was to investigate the influence of SMGT treatment and exogenous DNA uptake on sperm quality. Even after a coincubation with a 20-fold larger amount (100 microg/mL) of DNA than usual (5 microg/mL), sperm quality parameters were not significantly affected, confirming the hypothesis that the SMGT protocol itself or the amount of bound DNA do not compromise the possibility of an extended employment of SMGT. More importantly, we found that semen used for in vitro fertilization 24h after DNA uptake gave good cleavage (60% vs. 58%, treated vs. control) and developmental rates definitely positive (41% vs. 48%, treated vs. control). These good results are connected to a competitive efficiency of transformation (62%) due to the numerous improvements in SMGT technique. We demonstrate that SMGT-treated spermatozoa retain good quality and fertilization potential for at least 24h, expanding the possibility to apply transgenesis in field conditions in swine, where the greatest hurdles are fertilization timing and plain procedure.


Asunto(s)
Fertilización/fisiología , Técnicas de Transferencia de Gen , Ingeniería Genética/métodos , Espermatozoides/citología , Espermatozoides/metabolismo , Porcinos/fisiología , Animales , Células Cultivadas , Eficiencia , Embrión de Mamíferos , Desarrollo Embrionario/fisiología , Femenino , Fertilización In Vitro/veterinaria , Masculino , Control de Calidad , Análisis de Semen , Espermatozoides/fisiología , Porcinos/embriología , Porcinos/genética
17.
Eur J Med Res ; 14(3): 136-8, 2009 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-19380285

RESUMEN

Multiclass-drug resistance, often caused by poor treatment compliance, is a challenging problem in all categories of HIV-infected patients. Selective pressure is higher in youth for both biological and behavioral reasons. We report the case of a 15-year-old Caucasian male, with vertically acquired HIV-1 infection, who failed several lines of antiretroviral therapy and was successfully treated with darunavir/ritonavir and etravirine.


Asunto(s)
Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/transmisión , Inhibidores de la Proteasa del VIH/uso terapéutico , Transmisión Vertical de Enfermedad Infecciosa , Piridazinas/uso terapéutico , Sulfonamidas/uso terapéutico , Adolescente , Darunavir , Farmacorresistencia Viral Múltiple/efectos de los fármacos , Quimioterapia Combinada , Humanos , Masculino , Nitrilos , Pirimidinas , Ritonavir/uso terapéutico , Resultado del Tratamiento
18.
Animal ; 3(2): 269-74, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22444230

RESUMEN

In pig production, artificial insemination is widely carried out and the use of fresh diluted semen is predominant. For this reason, there are increasing interests in developing new extenders and in establishing the optimal storage conditions for diluted spermatozoa. In the last few decades, we utilised a homemade diluent (swine fertilisation medium (SFM)) for spermatozoa manipulation and biotechnological application as the production of transgenic pigs utilising the sperm-mediated gene transfer technique. The purpose of the present study is therefore to analyse the ability of SFM, in comparison to four commercial extenders, in preserving the quality of diluted boar semen stored at 16.5°C till 15 days. We utilised some of the main predictive tests as objectively measured motility, acrosome and sperm membrane integrity, high mitochondrial membrane potential and pH. Based on our in vitro study, SFM could be declared as a good long-term extender, able to preserve spermatozoa quality as well as Androhep Enduraguard for up to 6 to 9 days and more.

19.
Reprod Domest Anim ; 43(4): 385-92, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18226022

RESUMEN

Heat shock proteins (Hsp)-60, -70 and -90 are important testis chaperones that fulfil several functions during sperm cell maturation. In post-meiotic cells, their expression may change or may be undetectable and in some species it may be evident in mature spermatozoa. The aims of this study were to verify whether Hsp60, -70 and -90 are present in the sperm, and to compare their localization in boar, stallion, cat and dog spermatozoa by immunofluorescence. Hsp-60 immunoreactivity was detected in sperm midpiece in all the species examined. In stallion sperm, Hsp70 signal was localized in the sub-equatorial band, whereas immunoreactivity was evident on the neck of dog spermatozoa and on both neck and sub-equatorial region of cat spermatozoa. In agreement with our previous observations, a triangular fluorescent signal in the equatorial segment of fresh boar sperm was detected. Hsp90 immunoreactivity was present in different portions of sperm tail: in the midpiece of both boar and cat spermatozoa and in the neck and throughout the tail in dog and stallion spermatozoa, respectively. When capacitation and acrosome reaction were induced in boar, stallion and dog spermatozoa, no changes in both Hsp60 and -90 were recorded by either Western blot or immunofluorescence. After induction of acrosome reaction, a Hsp70 redistribution in boar spermatozoa and an increased percentage of stallion spermatozoa showing the post-acrosomal signal were observed although no changes were recorded by Western blot; in dog spermatozoa, no changes in Hsp70 were found by Western blot and immunofluorescence after capacitation and acrosome reaction.


Asunto(s)
Reacción Acrosómica/fisiología , Chaperonina 60/metabolismo , Proteínas HSP70 de Choque Térmico/metabolismo , Proteínas HSP90 de Choque Térmico/metabolismo , Capacitación Espermática/fisiología , Espermatozoides/metabolismo , Animales , Western Blotting/veterinaria , Gatos , Perros , Técnica del Anticuerpo Fluorescente Indirecta/veterinaria , Caballos , Masculino , Especificidad de la Especie , Espermatogénesis/fisiología , Espermatozoides/citología , Porcinos , Distribución Tisular
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