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1.
J Antimicrob Chemother ; 71(3): 739-50, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26679249

RESUMEN

OBJECTIVES: This study aims to evaluate the reliability and clinical utility of NS3 sequencing in hepatitis C virus (HCV) 1-infected patients who were candidates to start a PI-containing regimen. METHODS: NS3 protease sequencing was performed by in-house-developed HCV-1 subtype-specific protocols. Phylogenetic analysis was used to test sequencing reliability and concordance with previous genotype/subtype assignment by commercial genotyping assays. RESULTS: Five hundred and sixty-seven HCV plasma samples with quantifiable HCV-RNA from 326 HCV-infected patients were collected between 2011 and 2014. Overall, the success rate of NS3 sequencing was 88.9%. The success rate between the two subtype protocols (HCV-1a/HCV-1b) was similarly high for samples with HCV-RNA >3 log IU/mL (>92% success rate), while it was slightly lower for HCV-1a samples with HCV-RNA ≤3 log IU/mL compared with HCV-1b samples. Phylogenetic analysis confirmed the genotype/subtype given by commercial genotyping assays in 92.9% (303/326) of cases analysed. In the remaining 23 cases (7.1%), 1 was HCV-1g (previously defined as subtype 1a), 1 was HCV-4d (previously defined as genotype 1b) and 1 was HCV-1b (previously defined as genotype 2a/2c). In the other cases, NS3 sequencing precisely resolved the either previous undetermined/discordant subtype 1 or double genotype/subtype assignment by commercial genotyping assays. Resistance-associated variants (RAVs) to PI were detected in 31.0% of samples. This prevalence changed according to PI experience (17.1% in PI-naive patients versus 79.2% in boceprevir/telaprevir/simeprevir-failing patients). Among 96 patients with available virological outcome following boceprevir/telaprevir treatment, a trend of association between baseline NS3 RAVs and virological failure was observed (particularly for HCV-1a-infected patients: 3/21 failing patients versus 0/22 achieving sustained virological response; P = 0.11). CONCLUSIONS: HCV-NS3 sequencing provides reliable results and at the same time gives two clinically relevant pieces of information: a correct subtype/genotype assignment and the detection of variants that may interfere with the efficacy of PI.


Asunto(s)
Farmacorresistencia Viral , Técnicas de Genotipaje/métodos , Hepacivirus/clasificación , Hepacivirus/efectos de los fármacos , Hepatitis C/virología , Mutación , Proteínas no Estructurales Virales/genética , Genotipo , Hepacivirus/genética , Hepacivirus/aislamiento & purificación , Humanos , ARN Viral/genética , Estudios Retrospectivos , Análisis de Secuencia de ADN
2.
Eur J Neurol ; 23(1): 140-7, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26453465

RESUMEN

BACKGROUND AND PURPOSE: Infectious mononucleosis (IM) caused by Epstein-Barr virus (EBV) has been associated with increased risk of multiple sclerosis (MS). However, the mechanism linking these pathologies is unclear. Different reports indicate the association of EBV, and recently Mycobacterium avium subsp. paratuberculosis (MAP), with MS. For a better understanding of the role of these pathogens, the host response induced by selected antigenic peptides in subjects with a history of IM that significantly increases the risk of MS was investigated. METHODS: Both humoral and cell-mediated response against peptides able to induce a specific immune activation in MS patients deriving from lytic and latent EBV antigens BOLF1(305-320), EBNA1(400-413), from MAP MAP_4027(18-32), MAP_0106c(121-132) and from human proteins IRF5(424-434) and MBP(85-98) in subjects with current and past IM were examined. RESULTS: EBNA1 and MAP_0106c peptides were able to induce a humoral immune response in subjects with a history of clinical IM in an independent manner. Moreover, these peptides were capable of inducing pro-inflammatory cytokine interferon γ by CD4+ and CD8+ T lymphocytes and interleukin 6 and tumour necrosis factor α by CD14+ monocyte cells. CONCLUSION: Our results highlight that EBV and MAP may be involved independently in the same causal process leading to MS in subjects with a history of IM.


Asunto(s)
Herpesvirus Humano 4/inmunología , Mononucleosis Infecciosa/inmunología , Esclerosis Múltiple/inmunología , Mycobacterium avium subsp. paratuberculosis/inmunología , Adulto , Antígenos Nucleares del Virus de Epstein-Barr/inmunología , Femenino , Humanos , Mononucleosis Infecciosa/complicaciones , Masculino , Esclerosis Múltiple/etiología , Péptidos/inmunología , Adulto Joven
3.
Reprod Fertil Dev ; 28(6): 750-6, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25375207

RESUMEN

In order to investigate if the melatonin receptor 1A (MTNR1A) and kisspeptin (KiSS-1) genes influence the reproductive response to melatonin treatment, 510 Sarda ewe lambs were divided into groups C (control) and M; Group M received one melatonin implant (18mg). After 35 days rams were introduced for 40 days and subsequent lambing dates and number of newborns were recorded. The MTNR1A gene Exon II and KiSS-1 gene Exon I were amplified and genotyped by restriction fragment length polymorphism (RFLP) and single-strand conformation polymorphism analysis. Two single nucleotide polymorphisms (SNPs; C606T and G612A) in MTNR1A and one (G1035A) in KiSS-1 were found. The most frequent genotypes were G/G (63%) and C/C (53%) for MTNR1A and G/G (92%) for KiSS-1. Treated animals showed a higher lambing rate (P<0.05) and an advanced lambing date (P<0.05) compared with controls. The three SNPs did not influence the onset of reproductive activity. The majority of the G/G animals of Group M lambed before 190 days after ram introduction (P<0.05), while in Group C a higher number of G/G animals lambed after this date. Data revealed the positive effect of melatonin treatment on the time of first conception in ewe lambs and highlighted that the G/G genotype of the MTNR1A gene is able to influence the reproductive response to melatonin treatment.


Asunto(s)
Antioxidantes/farmacología , Fertilización/efectos de los fármacos , Kisspeptinas/metabolismo , Melatonina/farmacología , Polimorfismo de Nucleótido Simple , Receptor de Melatonina MT1/agonistas , Oveja Doméstica/fisiología , Alelos , Sustitución de Aminoácidos , Análisis del Polimorfismo de Longitud de Fragmentos Amplificados/veterinaria , Animales , Antioxidantes/administración & dosificación , Implantes de Medicamentos , Resistencia a Medicamentos , Exones , Femenino , Fármacos para la Fertilidad Femenina/administración & dosificación , Fármacos para la Fertilidad Femenina/farmacología , Frecuencia de los Genes , Estudios de Asociación Genética/veterinaria , Italia , Kisspeptinas/genética , Nacimiento Vivo/veterinaria , Melatonina/administración & dosificación , Receptor de Melatonina MT1/genética , Receptor de Melatonina MT1/metabolismo , Oveja Doméstica/genética , Oveja Doméstica/crecimiento & desarrollo
4.
Mol Biol Rep ; 41(9): 5787-92, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24965143

RESUMEN

The pituitary-specific positive transcription factor 1 (POU1F1) gene has been the subject of many recent studies because of its important roles in growth and development of mammals. In this study, we investigated the single nucleotide polymorphisms (SNPs) at the third exon of POU1F1 gene and its association with growth and biometric traits and blood metabolites in two Iranian sheep breeds, Zel and Lori-Bakhtiari. Blood samples from 90 Lori-Bakhtiari and 90 Zel sheep were collected to extract DNA and the 295-bp fragment of the POU1F1 gene was amplified and the restriction fragment length polymorphism (RFLP) technique was adopted for genotyping. A SNP was identified in both Lori-Bakhtiari and Zel sheep breeds, which represents a non-synonymous single base mutation at restriction site for endonuclease AciI. The results revealed differential frequencies of alleles between the two studied breeds, where A allele was more frequent in Lori-Bakhtiari breed, while G allele was more frequent in Zel breed. When POU1F1 genotypes were tested, the animals with AA genotype had a higher weaning weight than those with GG genotype (p < 0.05), however there were not significant association between genotypes and birth weight, biometric traits (body length, body height, heart girth, thigh girth and abdominal girth) and blood metabolites (triglyceride and cholesterol) of the studied breeds (p > 0.05). These findings imply that the POU1F1 polymorphism may affect weaning weight, thus can be used as a molecular marker for this production trait.


Asunto(s)
Fenotipo , Polimorfismo de Nucleótido Simple , Oveja Doméstica/genética , Factor de Transcripción Pit-1/genética , Alelos , Animales , Peso Corporal , Colesterol/sangre , Exones , Marcadores Genéticos , Irán , Filogeografía , Polimorfismo de Longitud del Fragmento de Restricción , Factor de Transcripción Pit-1/metabolismo , Triglicéridos/sangre
5.
Parasitol Res ; 113(4): 1505-9, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24525757

RESUMEN

Dog heartworms Angiostrongylus vasorum and Dirofilaria immitis cause severe parasitological diseases; the importance of these parasitosis is growing due to their health impact on animals, the possible zoonotic implications and the recent spreading across several European countries and previously non-endemic areas. The aim of this study is to update the epidemiological scenario of cardiopulmonary nematodes A. vasorum and D. immitis in dogs of Sardinia island and to perform a morphological identification of larvae by the use of the Baermann and Knott techniques respectively and the molecular characterization of the mitochondrial cytochrome c oxidase subunit I (cox1) and the second ribosomal transcribed spacer region (ITS-2) of larvae L1 of A. vasorum. In the present study, 3.4% (5/146) of dogs resulted positive at Baermann technique for A. vasorum while 8.9% (61/684) to D. immitis. If on one side A. vasorum can be considered an emerging parasite in Sardinia, the parasitic pressure and the risk of infection for D. immitis in the island seems to be increased compared with the recent past.


Asunto(s)
Dirofilariasis/epidemiología , Enfermedades de los Perros/parasitología , Cardiopatías/veterinaria , Infecciones por Strongylida/epidemiología , Angiostrongylus/genética , Animales , Dirofilaria immitis/genética , Enfermedades de los Perros/epidemiología , Perros , Femenino , Cardiopatías/epidemiología , Cardiopatías/parasitología , Italia/epidemiología , Larva/parasitología , Masculino , Prevalencia , Infecciones por Strongylida/veterinaria
6.
Am J Transplant ; 13(10): 2722-9, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24007361

RESUMEN

Primary graft failure and chronic lung allograft dysfunction (CLAD) limit lung transplant long-term outcomes. Various lung diseases have been correlated with surfactant protein (SP) expression and polymorphisms. We sought to investigate the role of SP expression in lung allografts prior to implantation, in relation to posttransplant outcomes. The expression of SP-(A, B, C, D) mRNA was assayed in 42 allografts. Posttransplant assessments include pulmonary function tests, bronchoscopy, broncho-alveolar lavage fluid (BALF) and biopsies to determine allograft rejection. BALF was assayed for SP-A, SP-D in addition to cytokines IL-8, IL-12 and IL-2. The diagnosis of CLAD was evaluated 6 months after transplantation. Lung allografts with low SP-A mRNA expression prior to implantation reduced survival (Log-rank p < 0.0001). No association was noted for the other SPs. Allografts with low SP-A mRNA had greater IL-2 (p = 0.03) and IL-12 (p < 0.0001) in the BALF and a greater incidence of rejection episodes (p = 0.003). Levels of SP-A mRNA expression were associated with the SP-A2 polymorphisms (p = 0.015). Specifically, genotype 1A1A(0) was associated with lower SP-A mRNA expression (p < 0.05). Lung allografts with low levels of SP-A mRNA expression are associated with reduced survival. Lung allograft SP-A mRNA expression appears to be associated with SP-A gene polymorphisms.


Asunto(s)
Rechazo de Injerto/genética , Enfermedades Pulmonares/cirugía , Trasplante de Pulmón , Polimorfismo Genético/genética , Proteína A Asociada a Surfactante Pulmonar/genética , Adulto , Anciano , Aloinjertos , Líquido del Lavado Bronquioalveolar , Citocinas/genética , Femenino , Estudios de Seguimiento , Rechazo de Injerto/diagnóstico , Rechazo de Injerto/mortalidad , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Pronóstico , Estudios Prospectivos , Proteína D Asociada a Surfactante Pulmonar/genética , ARN Mensajero/genética , Estudios Retrospectivos , Tasa de Supervivencia
7.
Infection ; 41(2): 347-53, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22971938

RESUMEN

PURPOSE: The objective of our study was to evaluate the presence of respiratory symptoms and chronic obstructive pulmonary disease (COPD) in a human immunodeficiency virus (HIV)-infected outpatient population and to further investigate the role of highly active antiretroviral therapy (HAART) and other possibly associated risk factors. METHODS: We consecutively enrolled in a cross-sectional study HIV-infected patients and HIV-negative age, sex and smoking status matched controls. All participants completed a questionnaire for pulmonary symptoms and underwent a complete spirometry. RESULTS: We enrolled 111 HIV-infected patients and 65 HIV-negative age- and sex-matched controls. HIV-infected patients had a significantly higher prevalence of any respiratory symptom (p = 0.002), cough (p = 0.006) and dyspnoea (p = 0.02). HIV-infected patients also had a significantly higher prevalence of COPD in respect of HIV-negative controls (p = 0.008). Furthermore, HIV-infected individuals had significantly (p = 0.002) lower forced expiratory volume at one second (FEV1) and FEV1/forced vital capacity (FVC) ratio (Tiffeneau index) (p = 0.028), whereas the total lung capacity (TLC) was significantly higher (p = 0.018). In the multivariate analysis, significant predictors of respiratory symptoms were current smoking [adjusted odds ratio (AOR) 11.18; 95 % confidence interval (CI) 3.89-32.12] and previous bacterial pneumonia (AOR 4.41; 95 % CI 1.13-17.13), whereas the only significant predictor of COPD was current smoking (AOR 5.94; 95 % CI 1.77-19.96). HAART receipt was not associated with respiratory symptoms nor with COPD. CONCLUSIONS: We evidenced a high prevalence of respiratory symptoms and COPD among HIV-infected patients. HIV infection, current cigarette smoking and previous bacterial pneumonia seem to play a significant role in the development of respiratory symptoms and COPD. Thus, our results suggest that the most at-risk HIV-infected patients should be screened for COPD to early identify those who may need specific treatment.


Asunto(s)
Terapia Antirretroviral Altamente Activa , Infecciones por VIH/epidemiología , Enfermedad Pulmonar Obstructiva Crónica/epidemiología , Enfermedad Pulmonar Obstructiva Crónica/virología , Adulto , Estudios de Casos y Controles , Comorbilidad , Intervalos de Confianza , Estudios Transversales , Femenino , Volumen Espiratorio Forzado , Infecciones por VIH/tratamiento farmacológico , Inhibidores de la Proteasa del VIH/farmacología , Humanos , Pulmón/patología , Masculino , Persona de Mediana Edad , Análisis Multivariante , Oportunidad Relativa , Prevalencia , Factores de Riesgo , Ritonavir/farmacología , Fumar/efectos adversos , Espirometría , Encuestas y Cuestionarios , Capacidad Pulmonar Total
8.
Infection ; 41(1): 69-76, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23264095

RESUMEN

PURPOSE: The prevalence of anti-hepatitis E virus (HEV) and anti-hepatitis A virus (HAV), as well as the possible links with socio-demographic and other viral risks factors, were evaluated in an inmates population. METHODS: The study population consisted of 973 consecutively recruited inmates of eight Italian prisons. RESULTS: The anti-HEV prevalence was 11.6 % (113/973). It increased significantly by age (χ(2) for linear trend: p = 0.001) and was significantly higher among non-Italian compared to Italian inmates (15.3 vs. 10.7 %, respectively). Age >40 years [odds ratio (OR) 2.1; 95 % confidence interval (CI) 1.4-3.1], non-Italian citizenship (OR 1.8; 95 % CI 1.1-2.9) and anti-HIV seropositivity (OR 2.2; 95 % CI 1.2-4.2) were the only factors independently associated to anti-HEV positivity by logistic regression analysis. The overall anti-HAV prevalence was 86.4 %, and was significantly higher in non-Italian compared to Italian prisoners (92.6 vs. 84.9 %, respectively; p = 0.02). Age older than 40 years (OR 3.6; 95 % CI 2.2-5.9), <5 years formal education (OR 2.1; 95 % CI 1.3-3.2) and non-Italian nationality (OR 2.7; 95 % CI 1.5-4.8) were factors independently associated to anti-HAV positivity by the logistic regression analysis. CONCLUSIONS: Compared to the general population, significantly higher anti-HEV and anti-HAV prevalences were observed in an inmates population in Italy. Old age and non-Italian nationality were factors independently related to both HEV and HAV exposures. This data suggest the important role of low socio-economic factors in the transmission of both infections in high-risk populations. The possible epidemiological and/or pathogenetic links between HEV and HIV exposures need to be studied further.


Asunto(s)
Virus de la Hepatitis A/inmunología , Hepatitis A/epidemiología , Virus de la Hepatitis E/inmunología , Hepatitis E/epidemiología , Vigilancia de la Población , Adolescente , Adulto , Factores de Edad , Anciano , Femenino , Anticuerpos Antihepatitis/sangre , Anticuerpos Antihepatitis/inmunología , Humanos , Italia/epidemiología , Masculino , Persona de Mediana Edad , Factores de Riesgo , Estudios Seroepidemiológicos , Adulto Joven
9.
Mol Biol Rep ; 40(9): 5285-94, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23653010

RESUMEN

The purpose was to analyze the growth hormone GH1/GH2-N and GH2-Z gene copies and to assess their possible association with milk traits in Sarda sheep. Two hundred multiparous lactating ewes were monitored. The two gene copies were amplified separately and each was used as template for a nested PCR, to investigate single strand conformation polymorphism (SSCP) of the 5'UTR, exon-1, exon-5 and 3'UTR DNA regions. SSCP analysis revealed marked differences in the number of polymorphic patterns between the two genes. Sequencing revealed five nucleotide changes at the GH1/GH2-N gene. Five nucleotide changes occurred at the GH2-Z gene: one was located in exon-5 (c.556G > A) and resulted in a putative amino acid substitution G186S. All the nucleotide changes were copy-specific, except c.*30delT, which was common to both GH1/GH2-N and GH2-Z. Variability in the promoter regions of each gene might have consequences on the expression level, due to the involvement in potential transcription factor binding sites. Both gene copies influenced milk yield. A correlation with milk protein and casein content was also evidenced. These results may have implications that make them useful for future breeding strategies in dairy sheep breeding.


Asunto(s)
Hormona del Crecimiento/genética , Leche/fisiología , Polimorfismo Genético/genética , Ovinos/genética , Animales , Secuencia de Bases , Cruzamiento/métodos , Cartilla de ADN/genética , Industria Lechera/métodos , Componentes del Gen , Leche/estadística & datos numéricos , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa/veterinaria , Polimorfismo Conformacional Retorcido-Simple/genética , Análisis de Secuencia de ADN/veterinaria , Espectrofotometría Infrarroja/veterinaria
10.
Nature ; 450(7170): 650-3, 2007 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-18046398

RESUMEN

Venus, unlike Earth, is an extremely dry planet although both began with similar masses, distances from the Sun, and presumably water inventories. The high deuterium-to-hydrogen ratio in the venusian atmosphere relative to Earth's also indicates that the atmosphere has undergone significantly different evolution over the age of the Solar System. Present-day thermal escape is low for all atmospheric species. However, hydrogen can escape by means of collisions with hot atoms from ionospheric photochemistry, and although the bulk of O and O2 are gravitationally bound, heavy ions have been observed to escape through interaction with the solar wind. Nevertheless, their relative rates of escape, spatial distribution, and composition could not be determined from these previous measurements. Here we report Venus Express measurements showing that the dominant escaping ions are O+, He+ and H+. The escaping ions leave Venus through the plasma sheet (a central portion of the plasma wake) and in a boundary layer of the induced magnetosphere. The escape rate ratios are Q(H+)/Q(O+) = 1.9; Q(He+)/Q(O+) = 0.07. The first of these implies that the escape of H+ and O+, together with the estimated escape of neutral hydrogen and oxygen, currently takes place near the stoichometric ratio corresponding to water.

11.
Reprod Fertil Dev ; 24(7): 983-7, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22935159

RESUMEN

A melatonin receptor 1A (MTNR1A) gene polymorphism in adult buffaloes has been reported to affect reproductive seasonality. Consequently, the aim of the present study was to assess whether this polymorphism can affect age at first conception and the interval between first and second calving in Mediterranean Italian buffaloes. The allelic frequency of the C and T alleles was 0.44 and 0.56, respectively, whereas the genotypic frequency was 26% for C/C, 40% for C/T and 34% for T/T. The average age at first mating was approximately 20 months, whereas that at calving was approximately 32 months. The largest number of calvings of primiparous buffaloes was recorded between June and October. No associations between genotype, first mating and subsequent calving date were found. The duration from first to second calving was longer in buffaloes with the C/C genotype compared with those with the T/T and C/T genotypes (P<0.01). The period of calving for buffaloes with the C/C genotype was mainly from July to September, whereas that for buffaloes with the T/T genotype was largely from March to May. The MTNR1A gene had no effect on the age of first conception in Mediterranean Italian buffaloes. Rather, the association between the T/T genotype and reproductive activity during days with a long photoperiod indicates that this polymorphism may be considered a genetic marker to identify buffaloes that are able to reproduce out of the breeding season.


Asunto(s)
Búfalos/genética , Polimorfismo Genético , Receptor de Melatonina MT1/genética , Reproducción/genética , Factores de Edad , Animales , Femenino , Frecuencia de los Genes , Genotipo , Italia , Masculino , Paridad/genética , Fenotipo , Fotoperiodo , Embarazo , Estaciones del Año , Conducta Sexual Animal
12.
Anim Reprod Sci ; 236: 106905, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34922186

RESUMEN

The aims of this study were 1) to investigate the effect of MTNR1A gene polymorphisms on reproductive performance in ewes of one Italian and two Slovenian dairy sheep breeds (Sarda, Istrian Premenka and Boska, respectively) which were located at different latitudes, and 2) to highlight if the different season of the male placement with females that was utilized in the different breeding systems in Sardinia (Italy) and Slovenia resulted in different effects of these polymorphisms on reproductive functions. Reproductively mature ewes (n = 100) from each breed were utilized to conduct the study. To evaluate the reproductive efficiency, lambing dates and number of lambs born were recorded per ewe; additionally, the duration in days from ram placement with ewes to lambing (DRPEL), litter size and the fertility rate were determined based on lambing dates. In each breed, there were eight nucleotide variations within the MTNR1A gene exon II, two of which (g.17355358 and g.17355171), respectively, resulted in a valine to isoleucine, and alanine to aspartic acid substitution, in amino acid sequence. The SNPs at position g.17355452 and g.17355458 were determined to have effects on reproductive performance. Genotypes C/C and C/T at g.17355452 in Bovska and Sarda and genotype A/A at g.17355458 in Istrian Pramenka were associated with a greater fertility and a lesser duration in days from ram placement with ewes to lambing. These findings confirmed that the nucleotide sequences of the MTNR1A gene could affect reproductive functions of Mediterranean sheep.


Asunto(s)
Anestro/genética , Polimorfismo de Nucleótido Simple , Receptor de Melatonina MT1/genética , Reproducción/genética , Oveja Doméstica/genética , Animales , Femenino , Italia , Receptor de Melatonina MT1/metabolismo , Eslovenia
13.
Analyst ; 136(12): 2471-81, 2011 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-21541414

RESUMEN

The differentiation of stem cells into multi-lineages is essential to aid the development of tissue engineered materials that replicate the functionality of their tissue of origin. For this study, Raman spectroscopy was used to monitor the formation of a bone-like apatite mineral during the differentiation of human mesenchymal stem cells (hMSCs) towards an osteogenic lineage. Raman spectroscopy observed dramatic changes in the region dominated by the stretching of phosphate groups (950-970 cm(-1)) during the period of 7-28 days. Changes were also seen at 1030 cm(-1) and 1070 cm(-1), which are associated with the P-O symmetric stretch of PO(4)(3-) and the C-O vibration in the plane stretch of CO(3)(2-). Multivariate factor analysis revealed the presence of various mineral species throughout the 28 day culture period. Bone mineral formation was observed first at day 14 and was identified as a crystalline, non-substituted apatite. During the later stages of culture, different mineral species were observed, namely an amorphous apatite and a carbonate, substituted apatite, all of which are known to be Raman markers for a bone-like material. Band area ratios revealed that both the carbonate-to-phosphate and mineral-to-matrix ratios increased with age. When taken together, these findings suggest that the osteogenic differentiation of hMSCs at early stages resembles endochondral ossification. Due to the various mineral species observed, namely a disordered amorphous apatite, a B-type carbonate-substituted apatite and a crystalline non-substituted hydroxyapatite, it is suggested that the bone-like mineral observed here can be compared to native bone. This work demonstrates the successful application of Raman spectroscopy combined with biological and multivariate analyses for monitoring the various mineral species, degree of mineralisation and the crystallinity of hMSCs as they differentiate into osteoblasts.


Asunto(s)
Células Madre Mesenquimatosas/citología , Osteoblastos/citología , Espectrometría Raman/métodos , Diferenciación Celular , Células Cultivadas , Humanos
14.
Infect Dis Now ; 51(7): 583-589, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34581277

RESUMEN

Vaccination plays a key role in the prevention of the infectious diseases, which the armed forces are exposed to during overseas deployments. Historically, the French military health service have always contributed greatly to progress in vaccination. The military immunization schedule has often been used as a model for the national schedule. It is a powerful tool, which is constantly evolving to take into account the risks of infection inherent in deployment and to include new scientific data, while still remaining aware of the limitations of vaccination from an individual and collective standpoint. In the current context of increasingly fast emergence or re-emergence of pathogens with a high epidemic potential, developing preventive medical measures is more necessary than ever before, and the French military health service is actively participating.


Asunto(s)
Medicina Militar , Personal Militar , Humanos , Esquemas de Inmunización , Organizaciones , Vacunación
15.
Heliyon ; 7(3): e06489, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33786396

RESUMEN

This research has two aims: (i) to characterize the coding sequence of the SREBP-1 gene in dairy sheep in order to investigate possible relationships between single nucleotide polymorphisms (SNPs) and milk traits; and (ii) to investigate possible relationship between SREBP-1 gene expression and nucleotide variation. Four hundred adult and multiparous lactating Sarda breed ewes were selected from two farms. Milk samples were collected from Day 30 to Day 150 of lactation to determine the mean yield, somatic cell count, lactose, fat, and protein content of the milk. RNA was extracted from the milk samples, after which the SREBP-1 gene coding regions were amplified and sequenced to scan mutations. Whilst eight SNPs were identified, none had statistically significant association with the analysed milk traits. Moreover, the identified expression patterns were not affected by the SNP or combined genotypes. High SREBP-1 gene expression levels were found to be correlated with high milk fat content (P < 0.01), indicating the crucial role of this gene in the milk fat synthesis. In conclusion, the polymorphisms found within SREBP-1 gene exhibited no significant associations with milk traits or with individual SREBP-1 mRNA expression patterns. The findings thus suggest that this small genetic variability may derive from the selection carried out in Sarda breed to improve milk yield.

16.
Nanoscale ; 13(38): 16324-16338, 2021 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-34570135

RESUMEN

Despite the high level of interest in bio-nano interactions, detailed intracellular mechanisms that govern nanoscale recognition and signalling still need to be unravelled. Magnetic nanoparticles (NPs) are valuable tools for elucidating complex intracellular bio-nano interactions. Using magnetic NPs, it is possible to isolate cell compartments that the particles interact with during intracellular trafficking. Studies at the subcellular scale rely heavily on optical microscopy; therefore, combining the advantages of magnetic recovery with excellent imaging properties to allow intracellular NP tracking is of utmost interest for the nanoscience field. However, it is a challenge to prepare highly magnetic NPs with a suitable fluorescence for the fluorescence imaging techniques typically used for biological studies. Here we present the synthesis of biocompatible multifunctional superparamagnetic multicore NPs with a bright fluorescent silica shell. The incorporation of an organic fluorophore in the silica surrounding the magnetic multicore was optimised to enable the particles to be tracked with the most common imaging techniques. To prevent dye loss resulting from silica dissolution in biological environments, which would reduce the time that the particles could be tracked, we added a thin dense encapsulating silica layer to the NPs which is highly stable in biological media. The synthesised multifunctional nanoparticles were evaluated in cell uptake experiments in which their intracellular location could be clearly identified using fluorescence imaging microscopy, even after 3 days. The magnetic properties of the iron oxide core enabled both efficient recovery of the NPs from the intracellular environment and the extraction of cell compartments involved in their intracellular trafficking. Thus, the NPs reported here provide a promising tool for the study of the processes regulating bio-nano interactions.


Asunto(s)
Nanopartículas Multifuncionales , Nanopartículas , Colorantes Fluorescentes , Nanopartículas Magnéticas de Óxido de Hierro , Dióxido de Silicio
17.
Phys Chem Chem Phys ; 12(18): 4759-67, 2010 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-20428556

RESUMEN

The self-assembly of flat organic molecules on metal surfaces is controlled, apart from the kinetic factors, by the interplay between the molecule-molecule and molecule-surface interactions. These are typically calculated using standard density functional theory within the generalized gradient approximation, which significantly underestimates nonlocal correlations, i.e. van der Waals (vdW) contributions, and thus affects interactions between molecules and the metal surface in the junction. In this paper we address this question systematically for the Au(111) surface and a number of popular flat organic molecules which form directional hydrogen bonds with each other. This is done using the recently developed first-principles vdW-DF method which takes into account the nonlocal nature of electron correlation [M. Dion et al., Phys. Rev. Lett. 2004, 92, 246401]. We report here a systematic study of such systems involving completely self-consistent vdW-DF calculations with full geometry relaxation. We find that the hydrogen bonding between the molecules is only insignificantly affected by the vdW contribution, both in the gas phase and on the gold surface. However, the adsorption energies of these molecules on the surface increase dramatically as compared with the ordinary density functional (within the generalized gradient approximation, GGA) calculations, in agreement with available experimental data and previous calculations performed within approximate or semiempirical models, and this is entirely due to the vdW contribution which provides the main binding mechanism. We also stress the importance of self-consistency in calculating the binding energy by the vdW-DF method since the results of non-self-consistent calculations in some cases may be off by up to 20%. Our calculations still support the usually made assumption of the molecule-surface interaction changing little laterally suggesting that single molecules and their small clusters should be quite mobile at room temperature on the surface. These findings support a gas-phase modeling for some flat metal surfaces, such as Au(111), and flat molecules, at least as a first approximation.

18.
Rev Sci Instrum ; 91(2): 023501, 2020 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-32113429

RESUMEN

Vacuum systems of neutral beam injectors have very demanding requirements in terms of pumping speed, throughput, and capacity. Due to their high affinity to hydrogenic species, porous sintered Non-Evaporable Getters (NEG) are a possible candidate for deployment in giant hydrogen ion sources and neutral beam injectors for fusion. This paper presents the numerical interpretation of experimental tests on a recently developed NEG cartridge, that is part of a modular pump under development for neutral beam injectors. The cartridge is composed of six stacks of ZAO® porous sintered NEG disks and a heater. It was tested under hydrogen loads relevant for neutral beam injectors, namely, at constant pressure or constant flow, such that the hydrogen pressure was in the range of 20 mPa-40 mPa. The result of the sorption test was reproduced by a three dimensional flow simulation in molecular regime to determine the actual pumping speed, the effective sticking coefficient, and the uniformity of the gas load on the various NEG disks. The procedure developed and the results obtained provide the basic understanding for interpreting the large-scale tests on the modular pump, consisting of 34 of these cartridges.

19.
Theriogenology ; 157: 42-47, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32799126

RESUMEN

The aim of this study was to determine whether polymorphisms of the melatonin receptor 1A (MTNR1A) gene influence the age at first mating in autumn-born ram-lambs and influence the out-of-season sexual activity of adult rams. In experiment 1, 24 Rasa Aragonesa ram-lambs born in September were genotyped for their RsaI and MnlI allelic variants of the MTNR1A gene, and the date of their first mounting with ejaculation after a period of semen collection training was documented. In experiment 2, the reproductive behavior, testicle size, and plasma testosterone concentrations of 18 adult rams (6 rams for each RsaI genotype) were recorded at the beginning (March) and end (May) of the seasonal anestrus. The number of days of training to achieve the first mating with ejaculation in T/T (C/C: 85.17 ± 12.08 C/T: 86.60 ± 18.87; T/T; 26.50 ± 24.50 d; P < 0.05), and G/G ram-lambs (G/G: 51.57 ± 14.99; A/G: 95.58 ± 10.95 d; P < 0.05) was significantly fewer than it was in the other genotypes. Likewise, for the RsaI genotype, 55% of the vulva-sniffing (P < 0.001), 48% of the approaches (P < 0.01), 48% of the mountings (P < 0.05) and 49% total activities (P < 0.001) were performed by T/T rams in March, and 50% of the sexual events in May (P < 0.001). For the Mnll variant, G/G rams performed a significantly (P < 0.001) larger proportion of the vulva-sniffing (41%), approaches (46%) and total activities (40%) in March, and 52% of the vulva-sniffing (P < 0.001), 43%, of the approaches (P < 0.001), 46% of the mountings (P < 0.05), and 47% of the total activities (P < 0.001) in May. Scrotal circumference, testicular volume, and plasma testosterone concentrations did not differ significantly among genotypes. Results confirmed that the polymorphisms of the MTNR1A gene sequence can influence reproductive performance in young and adult rams. Autumn-born ram-lambs that carried the T/T or G/G genotype had an advanced ability to reproduce, and T/T or G/G adult rams exhibited the most intense reproductive behavior. Genotyping might be a useful procedure for identifying the correct and rational use of rams in modern sheep farming.


Asunto(s)
Receptores de Melatonina , Reproducción , Conducta Sexual Animal , Animales , Femenino , Masculino , Embarazo , Receptores de Melatonina/genética , Reproducción/genética , Estaciones del Año , Ovinos/genética , Oveja Doméstica
20.
Anim Reprod Sci ; 216: 106352, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32414462

RESUMEN

The aim of the research was to describe the polymorphisms of the MTNR1A gene in three Slovenian sheep breeds, and determine whether these polymorphisms affect reproductive performance. A total of 100 Bovska, 110 Istrian Pramenka, and 108 Jezersko-Solcavska ewes, were used. The rams were placed with the ewes on 10 October (Bovska), and 20 September (Istrian Pramenka). At each farm, the lambing date and number of newborn lambs were recorded to evaluate the fertility rate, number of days from ram placement with ewes to lambing (DRIL), and litter size. The Jezersko-Solcavska rams were maintained with the ewes of the flock throughout the year and data related to lambing during the entire year were recorded. The DNA sequences indicated there were eight nucleotide variations and that in the position g.17355358 was always associated with that in the position g.17355452. For the Bovska breed, there was an association between the G/G genotype in the position g.17355452, and relatively greater fertility (P < 0.05) and a shorter DIRL (P < 0.05). For the Istrian Pramenka breed, the T/T genotype in the position g.17355458 was positively associated with a greater fertility (P < 0.05) and shorter DRIL (P < 0.05). For the Jezersko-Solcavska breed, ewes with the G/G genotype in the position g.17355452 lambed more when there was a decreasing photoperiod whereas the ewes with the A/A genotype lambed more (P < 0.05) during the period when there were increasing photoperiods. The different polymorphisms studied were associated with reproductive performance in the three Slovenian breeds.


Asunto(s)
Alelos , Fertilidad/genética , Receptor de Melatonina MT1/metabolismo , Ovinos/genética , Animales , Femenino , Regulación de la Expresión Génica , Genotipo , Polimorfismo de Nucleótido Simple , Embarazo , Receptor de Melatonina MT1/genética , Ovinos/fisiología
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