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2.
J Dairy Sci ; 100(1): 385-394, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28341048

RESUMO

Sheep milk is an important source of food, especially in Mediterranean countries, and is used in large part for cheese production. Milk technological traits are important for the sheep dairy industry, but research is lacking into the genetic variation of such traits. Therefore the aim of this study was to estimate the heritability of traditional milk coagulation properties and curd firmness modeled on time t (CFt) parameters, and their genetic relationships with test-day milk yield, composition (fat, protein, and casein content), and acidity in Sarda dairy sheep. Milk samples from 1,121 Sarda ewes from 23 flocks were analyzed for 5 traditional coagulation properties by lactodynamographic tests conducted for up to 60min: rennet coagulation time (min), curd-firming time (k20, min), and 3measures of curd firmness (a30, a45, and a60, mm). The 240 curd firmness observations (1 every 15 s) from each milk sample were recorded, and 4 parameters for each individual sample equation were estimated: rennet coagulation time estimated from the equation (RCTeq), the asymptotic potential curd firmness (CFP), the curd firming instant rate constant (kCF), and the syneresis instant rate constant (kSR). Two other derived traits were also calculated (CFmax, the maximum curd firmness value; and tmax, the attainment time). Multivariate analyses using Bayesian methodology were performed to estimate the genetic relationships of milk coagulation properties and CFt with the other traits; statistical inference was based on the marginal posterior distributions of the parameters of concern. The marginal posterior distribution of heritability estimates of milk yield (0.16±0.07) and composition (0.21±0.11 to 0.28±0.10) of Sarda ewes was similar to those often obtained for bovine species. The heritability of rennet coagulation time as a single point trait was also similar to that frequently obtained for cow milk (0.19±0.09), whereas the same trait calculated as an individual equation parameter exhibited larger genetic variation and a higher heritability estimate (0.32±0.11). The other curd firming and syneresis traits, whether as traditional single point observations or as individual equation parameters and derived traits, were characterized by heritability estimates lower than for coagulation time and for the corresponding bovine milk traits (0.06 to 0.14). Phenotypic and additive genetic correlations among the 11 technological traits contribute to describing the interdependencies and meanings of different traits. The additive genetic relationships of these technological traits with the single test-day milk yield and composition were variable and showed milk yield to have unfavorable effects on all measures of curd firmness (a30, a45, a60, CFP, and CFmax) and tmax, but favorable effects on both instant rate constants (kCF and kSR). Milk fat content had a positive effect on curd firmness traits, especially on those obtained from CFt equations, whereas the negative effects on both coagulation time traits were attributed to the milk protein and casein contents. Finally, in view of the estimated heritabilities and additive genetic correlations, enhancement of technological traits of sheep milk through selective breeding could be feasible in this population.


Assuntos
Teorema de Bayes , Leite/química , Ovinos , Animais , Caseínas , Bovinos , Queijo , Quimosina/metabolismo , Feminino , Proteínas do Leite/metabolismo , Fenótipo
3.
J Dairy Sci ; 100(5): 3526-3538, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28318586

RESUMO

The aim of this study was to apply Bayesian models to the Fourier-transform infrared spectroscopy spectra of individual sheep milk samples to derive calibration equations to predict traditional and modeled milk coagulation properties (MCP), and to assess the repeatability of MCP measures and their predictions. Data consisted of 1,002 individual milk samples collected from Sarda ewes reared in 22 farms in the region of Sardinia (Italy) for which MCP and modeled curd-firming parameters were available. Two milk samples were taken from 87 ewes and analyzed with the aim of estimating repeatability, whereas a single sample was taken from the other 915 ewes. Therefore, a total of 1,089 analyses were performed. For each sample, 2 spectra in the infrared region 5,011 to 925 cm-1 were available and averaged before data analysis. BayesB models were used to calibrate equations for each of the traits. Prediction accuracy was estimated for each trait and model using 20 replicates of a training-testing validation procedure. The repeatability of MCP measures and their predictions were also compared. The correlations between measured and predicted traits, in the external validation, were always higher than 0.5 (0.88 for rennet coagulation time). We confirmed that the most important element for finding the prediction accuracy is the repeatability of the gold standard analyses used for building calibration equations. Repeatability measures of the predicted traits were generally high (≥95%), even for those traits with moderate analytical repeatability. Our results show that Bayesian models applied to Fourier-transform infrared spectra are powerful tools for cheap and rapid prediction of important traits in ovine milk and, compared with other methods, could help in the interpretation of results.


Assuntos
Teorema de Bayes , Leite/química , Ovinos , Animais , Feminino , Fenótipo , Espectroscopia de Infravermelho com Transformada de Fourier/veterinária
4.
Anim Genet ; 47(6): 717-726, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27435993

RESUMO

Regulatory variation at the ovine casein genes could have important effects on the composition and coagulation properties of milk. Herewith, we have partially resequenced the promoters and the 3'-UTR of the four casein genes in 25 Sarda sheep. Alignment of these sequences allowed us to identify a total of 29 SNPs. This level of polymorphism (one SNP every 250 bp) is remarkably high if compared with SNP densities estimated in human genic regions (approximately one SNP per bp). The 29 SNPs identified in our resequencing experiment, plus three previously reported SNPs mapping to the lactalbumin, alpha (LALBA) and ß-lactoglobulin (BLG, also known as progestagen-associated endometrial protein, PAEP) genes, were genotyped with a multiplex TaqMan Open Array Real-Time PCR assay in 760 Sarda sheep with records for milk composition and coagulation properties. Association analysis revealed the existence of significant associations of CSN1S2 and CSN3 genotypes with milk protein and casein contents. Moreover, genotypes at CSN1S1 were significantly associated with rennet coagulation time, curd firming time and curd firmness, whereas CSN2 was associated with curd firming time. These results suggest that SNPs mapping to the promoters and 3'-UTRs of ovine casein genes may exert regulatory effects on gene expression and that they could be used for improving sheep milk quality and technological traits at the population level through marker assisted selection.


Assuntos
Regiões 3' não Traduzidas , Caseínas/genética , Lactalbumina/genética , Lactoglobulinas/genética , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , Carneiro Doméstico/genética , Animais , Quimosina/química , Genótipo , Desequilíbrio de Ligação , Leite , Fenótipo , Reação em Cadeia da Polimerase em Tempo Real
5.
J Dairy Sci ; 98(4): 2245-59, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25660749

RESUMO

This study investigated the modeling of curd-firming (CF) over time (CF(t)) of sheep milk. Milk samples from 1,121 Sarda ewes from 23 flocks were analyzed for coagulation properties. Lactodynamographic analyses were conducted for up to 60 min, and 240 CF individual observations from each sample were recorded. Individual sample CFt equation parameters (RCT(eq), rennet coagulation time; CF(P), asymptotic potential value of curd firmness; k(CF), curd-firming instant rate constant; and k(SR), curd syneresis instant rate constant) were estimated, and the derived traits (CF(max), the point at which CF(t) attained its maximum level, and tmax, the time at which CF(max) was attained) were calculated. The incidence of noncoagulating milk samples was 0.4%. The iterative estimation procedure applied to the individual coagulation data showed a small number of not-converged samples (4.4%), which had late coagulation and an almost linear pattern of the ascending part of the CF(t) curve that caused a high value of CF(P), a low value of k(CF), and a high value of k(SR). Converged samples were classified on the basis of their CF(t) curves into no-k(SR) (18.0%), low-k(SR) (72.6%), and high-k(SR) (4.5%). A CF(t) that was growing continuously because of the lack of the syneresis process characterized the no-k(SR) samples. The high-k(SR) samples had a much larger CFP, a smaller k(CF), and an anticipation of tmax, whereas the low-k(SR) samples had a fast k(CF) and a slower k(SR). The part of the average CF(t) curves that showed an increase was similar among the 3 different syneretic groups, whereas the part that decreased was different because of the expulsion of whey from the curd. The traditional milk coagulation properties recorded within 30 min were not able to detect any appreciable differences among the 4 groups of coagulating samples, which could lead to a large underestimation of the maximum CF of all samples (if predicted by a30), with the exception of the no-k(SR) samples. Large individual variability was found and was likely caused by the effects of the dairy system, such as flock size (on CF(max), t(max), and % ewes with no-k(SR) milk), flock within flock size (representing 11 to 43% of total variance for % ewes with no-k(SR) milk and CF(max), respectively), days in milk (on all model parameters and CF(max)), parity (on RCT(eq), k(SR), and CF(max)), daily milk yield (on RCT(eq) and CF(max)), and position of the individual pendulum that significantly affected model parameters and derived traits. In conclusion, the results showed that the modeling of coagulation, curd-firming, and syneresis is a suitable tool to achieve a deeper interpretation of the coagulation and curd-firming processes of sheep milk and also to study curd syneresis.


Assuntos
Laticínios , Leite/química , Animais , Quimosina/análise , Feminino , Lactação , Leite/metabolismo , Modelos Teóricos , Fenótipo , Ovinos , Proteínas do Soro do Leite/análise
6.
Anim Genet ; 45(5): 723-31, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24990661

RESUMO

The aim of the current work was to analyze, in the Sarda breed goat, genetic polymorphism within the casein genes and to assess their influence on milk traits. Genetic variants at the CSN1S1, CSN2, CSN1S2 and CSN3 gene loci were investigated using PCR-based methods, cloning and sequencing. Strong alleles prevailed at the CSN1S1 gene locus and defective alleles also were revealed. Null alleles were evidenced at each calcium-sensitive gene locus. At the CSN3 gene locus, we observed a prevalence of the CSN3 A and B alleles; the occurrence of rare alleles such as CSN3 B'', C, C', D, E and M; and the CSN3 S allele (GenBank KF644565) described here for the first time in Capra hircus. Statistical analysis showed that all genes, except CSN3, significantly influenced milk traits. The CSN1S1 BB and AB genotypes were associated with the highest percentages of protein (4.41 and 4.40 respectively) and fat (5.26 and 5.34 respectively) (P < 0.001). A relevant finding was that CSN2 and CSN1S2 genotypes affected milk protein content and yield. The polymorphism of the CSN2 gene affected milk protein percentage with the highest values recorded in the CSN2 AA goats (4.35, at P < 0.001). The CSN1S2 AC goats provided the highest fat (51.02 g/day) and protein (41.42 g/day) (P < 0.01) production. This information can be incorporated into selection schemes for the Sarda breed goat.


Assuntos
Caseínas/genética , Genótipo , Cabras/genética , Alelos , Animais , Cruzamento , Feminino , Frequência do Gene , Haplótipos , Masculino , Leite/química , Dados de Sequência Molecular , Família Multigênica , Polimorfismo Genético
7.
J Dairy Sci ; 97(11): 7247-57, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25151884

RESUMO

In this study, milk-coagulation properties (MCP) were characterized in the Sarda sheep breed. Milk composition and MCP [rennet-coagulation time (RCT), curd-firming time [time to reach a curd firmness of 20mm (k20)], and curd firmness (a30), (a45), and (a60)] were obtained extending the lactodynamographic analysis from 30 to 60 min from a population of 1,121 ewes from 23 different farms. Managerial characteristics of farms and parity, individual daily milk yields and stage of lactation of ewes were recorded. Data were analyzed using a mixed-model procedure with fixed effects of days in milk, parity, daily milk yield, and flock size and the random effect of the flock/test day nested within flock size. Sampled farms were classified as small (<300 ewes) and medium (300 to 600 ewes), and these were kept by family operations, or as large (>600 ewes), often operated through hired workers. Daily milk yield was, on average, 1.58 ± 0.79 L/d and variability for this trait was very high. The average content of fat, protein, and casein was respectively 6.41, 5.39, and 4.20%. The class of flock size had a significant effect only on curd firmness, whereas days in milk affected RCT and k20. The flock test day, parity, and daily milk yield were important sources of variation for all MCP. The mean value of RCT (8.6 min) and the low occurrence of noncoagulating samples (0.44%) confirmed the excellent coagulation ability of sheep milk compared with cattle milk. A more rapid coagulation was observed in mid-lactating, primiparous, and high-yielding ewes. The k20 was usually reached in less than 2 min after gelation, with the most favorable values at mid lactation. The mean value of curd firmness 30 min after rennet addition (a30) was, on average, 50mm and decreased to 46 and 42 mm respectively after 45 (a45) and 60 min (a60). The decreasing value of curd-firmness traits was likely to be caused by curd syneresis and whey expulsion. The correlation between RCT and a30 was much lower than in dairy cows and about null for a45 and a60. This means that curd firmness in dairy ewes is almost independent of gelation time and this can provide specific information for this species. In conclusion, this study showed that milk from Sarda sheep is characterized by an earlier gelation, a faster increase in curd firmness with time, and greater curd firmness after 30 min compared with dairy cows. Furthermore, correlations between MCP in sheep are much lower than in bovines and some of the assumptions and interpretations related to cows cannot be applied to sheep.


Assuntos
Leite/química , Ovinos/fisiologia , Animais , Caseínas/metabolismo , Precipitação Química , Feminino , Lactação , Leite/metabolismo , Fenótipo
8.
J Dairy Sci ; 97(7): 4018-28, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24819130

RESUMO

The aim of this study was to test the modeling of curd-firming (CF) measures and to compare the sheep milk of 3 Alpine breeds supplemented with or without rumen-protected conjugated linoleic acid (rpCLA). Twenty-four ewes of the Brogna, Foza, and Lamon breeds were allotted to 6 pens (2 pens/breed) and fed a diet composed of corn grain, corn silage, dried sugar beet pulp, soybean meal, wheat bran, wheat straw, and a vitamin-mineral mixture. The rpCLA supplement (12 g/d per ewe plus 4 g/d for each lamb older than 30 d) was mixed into the diet of 1 pen per sheep breed (3 pens/treatment) to provide an average of 0.945 and 0.915 g/d per ewe of the cis-9,trans-11 C18:2 and trans-10,cis-12 C18:2 conjugated linoleic acid isomers, respectively. The trial started at 38 ± 23 d after parturition, and individual morning milk samples were collected on d 16, 23, 37, 44, and 59 of the trial. Milk samples were analyzed for composition, and duplicate samples were assessed for milk coagulation properties (MCP). A total of 180 CF measures for each sample (1 every 15s) were recorded. Model parameters were the rennet coagulation time, the asymptotic potential CF, the CF instant rate constant, the syneresis instant rate constant, the maximum CF achieved within 45 min (CFmax), and the time at achievement of CFmax. The data were analyzed using a hierarchical model that considered the fixed effects of breed, diet, lamb birth, and initial days in milk, which were tested on individual ewe (random) variance; the fixed effect of sampling day, which was tested on the within-ewe sample (random) variance; and the fixed effect of instrument or cuvette position (only for MCP), which was tested on the residual (replicates within samples) variance. The local Alpine sheep breeds displayed similar milk compositions, traditional MCP, and CF modeling parameters. Supplementation with rpCLA triggered changes in milk composition and worsened MCP (e.g., delayed rennet coagulation time, slower CF instant rate constant, and a doubling of syneresis instant rate constant), but did not influence potential CF. Overall, our results indicate that rpCLA supplementation reduced the actual maximum CF (CFmax) but did not modify the interval between rennet addition and CFmax or time to CFmax.


Assuntos
Suplementos Nutricionais , Ácidos Linoleicos Conjugados/metabolismo , Leite/química , Modelos Biológicos , Carneiro Doméstico/metabolismo , Ração Animal/análise , Animais , Cruzamento , Dieta/veterinária , Feminino , Lactação , Distribuição Aleatória , Carneiro Doméstico/genética
9.
Mol Biol Rep ; 40(9): 5285-94, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23653010

RESUMO

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.


Assuntos
Hormônio do Crescimento/genética , Leite/fisiologia , Polimorfismo Genético/genética , Ovinos/genética , Animais , Sequência de Bases , Cruzamento/métodos , Primers do DNA/genética , Indústria de Laticínios/métodos , Componentes do Gene , Leite/estatística & dados numéricos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase/veterinária , Polimorfismo Conformacional de Fita Simples/genética , Análise de Sequência de DNA/veterinária , Espectrofotometria Infravermelho/veterinária
10.
Neurol Sci ; 34(4): 521-8, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22526763

RESUMO

Natalizumab is one option for multiple sclerosis patients responding poorly to classical immunomodulators, but pilot studies did not point to its effectiveness as a second-line therapy. Aim of this study was to assess the efficacy of natalizumab as second-line therapy in patients switching from disease modifying therapies (DMTs) in a clinical setting. We retrospectively selected patients who had been treated with natalizumab for at least 12 months after switching from one or more DMTs. We collected clinical and neuroradiological data and we analysed the reduction in annualised relapse rate (ARR), the change of Expanded Disability Status Scale (EDSS) and the reduction of contrast-enhancing lesions (CELs) at magnetic resonance imaging (MRI) of the brain at 12 months of natalizumab and of previous DMT therapy. Fifty patients were included in the analysis (11 males, 39 females).We observed a reduction of ARR on natalizumab (p = 0.000) and a statistically significant different trend of relapse event between the two treatments (p = 0.0149). EDSS was stable during natalizumab therapy whilst it showed an increase on DMTs (p = 0.0244). The number of CELs decreased significantly (p = 0.006) during the 12 months of treatment with natalizumab, whilst it was stable on DMTs. Natalizumab showed to decrease ARR, stabilize EDSS, increase the percentage of CELs free patients and decrease the number of CELs in a group of 50 poor responders to classical DMT, after the first 12 months of therapy.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Fatores Imunológicos/uso terapêutico , Esclerose Múltipla/tratamento farmacológico , Adulto , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Avaliação da Deficiência , Feminino , Humanos , Estimativa de Kaplan-Meier , Imageamento por Ressonância Magnética , Masculino , Esclerose Múltipla/patologia , Natalizumab , Avaliação de Resultados em Cuidados de Saúde , Recidiva , Adulto Jovem
11.
Acta Neurol Scand ; 126(5): 306-14, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22107083

RESUMO

BACKGROUND: No head-to-head study has been performed yet to assess whether natalizumab is more effective than classical immunomodulators in multiple sclerosis (MS). AIM: To retrospectively compare the efficacy of natalizumab vs IFN beta 1a SC (44 µg; Rebif(®) ) on clinical and radiological findings in two matched cohorts of patients with MS. PATIENTS AND METHODS: We retrospectively enrolled two cohorts of 42 patients (F/M: 35/7) with relapsing-remitting multiple sclerosis treated with natalizumab or IFN beta 1a for at least 12 consecutive months. Outcome measures were annualized relapse rate (ARR), changes in expanded disability status scale (EDSS) score, and number of contrast-enhancing lesions (CELs) at magnetic resonance imaging (MRI). RESULTS: In both groups, the ARR in the 12 months of treatment was lower than in the 12 months before therapy (0.24 vs 1.50 in natalizumab-treated group, P < 0.0000; 0.55 vs 1.10 in IFN beta 1a-treated group, P = 0.0006), being the effect of natalizumab significantly stronger (P = 0.0125). EDSS reduction was significantly different between the two groups in favor of natalizumab (P = 0.0018). The frequency and number of CELs per patient were decreased in both groups. In the second year, the treatment affected ARR and EDSS progression in the two groups of patients similarly to the first year, whereas number of CELs decreased more significantly in natalizumab group (P = 0.008). CONCLUSIONS: After 12 and 24 months of therapy, natalizumab was more effective than IFN beta 1a SC on both disease activity and disability progression. Prospective head-to-head studies would be helpful to further evaluate the differences observed in the MRI outcomes.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Fatores Imunológicos/uso terapêutico , Interferon beta/uso terapêutico , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Encéfalo/patologia , Sistema Nervoso Central/patologia , Avaliação da Deficiência , Progressão da Doença , Feminino , Humanos , Masculino , Esclerose Múltipla Recidivante-Remitente/patologia , Esclerose Múltipla Recidivante-Remitente/prevenção & controle , Natalizumab , Estudos Retrospectivos , Prevenção Secundária
12.
Reprod Fertil Dev ; 24(7): 983-7, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22935159

RESUMO

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.


Assuntos
Búfalos/genética , Polimorfismo Genético , Receptor MT1 de Melatonina/genética , Reprodução/genética , Fatores Etários , Animais , Feminino , Frequência do Gene , Genótipo , Itália , Masculino , Paridade/genética , Fenótipo , Fotoperíodo , Gravidez , Estações do Ano , Comportamento Sexual Animal
13.
Phys Rev Lett ; 106(12): 121304, 2011 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-21517296

RESUMO

Within a genuinely gauge invariant approach recently developed for the computation of the cosmological backreaction, we study, in a cosmological inflationary context and with respect to various observers, the impact of scalar fluctuations on the space-time dynamics in the long wavelength limit. We stress that such a quantum backreaction effect is evaluated in a truly gauge independent way using a set of effective equations which describe the dynamics of the averaged geometry. In particular we show under what conditions the free falling (geodetic) observers do not experience any scalar-induced backreaction in the effective Hubble rate and fluid equation of state.

14.
Eur J Neurol ; 18(12): 1402-6, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21585623

RESUMO

BACKGROUND: Insulin-like growth factor (IGF)-I has a role in remyelination, and insulin-like growth factor-binding protein-3 (IGFBP-3) might reduce its bioavailability. A role of IGFBP-3 in multiple sclerosis (MS) progression was hypothesized in patients with primary progressive (PP) MS. OBJECTIVE: To evaluate serum levels of IGF-I and IGFBP-3 in patients with relapsing-remitting (RR) and secondary progressive (SP) MS and their correlations with disease activity and progression. METHODS: Sixty-three (41 RR and 22 SP) 'naive' MS patients and 60 age-matched healthy controls were enrolled. Patients were assessed through clinical [Expanded Disability Status Scale (EDSS), Multiple Sclerosis Severity Scale (MSSS), number of relapses] and laboratory investigations. IGF-I and IGFBP-3 were measured by ELISA. RESULTS: Levels of IGF-I and IGFBP-3 were similar in the two MS groups. IGFBP-3 levels were higher in patients with MS than in controls (P < 0.001), with a reduction in IGF-I/BP3 ratio (P < 0.001). Patients showing IGFBP-3 levels higher than 2SD of the normal population had a higher EDSS (mean EDSS 3.7 vs. 2.8, P = 0.021). MSSS was not related to IGF-I or IGFBP-3 serum levels. CONCLUSIONS: Our patients showed high IGFBP-3 serum levels respect to controls and higher serum levels were associated with a higher EDSS, despite of comparable disease duration. Therefore, MS and higher disability seem to be associated with a reduction in bioavailability of IGF-I. MSSS score was not related to IGFBP-3 levels, suggesting that IGFBP-3 might not have the pathogenetic role previously suggested for PP MS, in the mechanism of progression in the SP form of disease.


Assuntos
Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Fator de Crescimento Insulin-Like I/análise , Esclerose Múltipla Crônica Progressiva/sangue , Esclerose Múltipla Recidivante-Remitente/sangue , Adulto , Fatores Etários , Estudos de Casos e Controles , Feminino , Humanos , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/fisiologia , Fator de Crescimento Insulin-Like I/fisiologia , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla Crônica Progressiva/fisiopatologia , Esclerose Múltipla Recidivante-Remitente/fisiopatologia , Índice de Gravidade de Doença , Fatores de Tempo
15.
Neurol Sci ; 32(2): 287-92, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21308385

RESUMO

The identification of predictive factors of NAbs development might have a relevant impact on clinical practice. Our objective is to look after predictive factors of NAbs development in MS IFN Beta-1b-treated patients. Database was screened for patients on IFN Beta-1b treatment with an Expanded Disability Status Scale (EDSS) at a baseline between 1 and 3.5, disease duration shorter than 15 years, and NAbs analysis performed every 6 months. The NAbs positive status was analysed in relation to baseline clinical, neuropsychological and brain imaging measures. Forty-nine patients were included. Sixteen patients had become NAbs positive at some point on IFN therapy (35%). NAbs producers differed from not producers for higher incidence of cognitive deficit and higher lesion load (OR = 5.0 and 5.6, respectively). Our study suggests that NAbs development might be a marker of a more aggressive disease and that worse outcome in NAbs producers might be biased by baseline condition.


Assuntos
Adjuvantes Imunológicos/uso terapêutico , Anticorpos Neutralizantes/biossíntese , Interferon beta/uso terapêutico , Esclerose Múltipla Recidivante-Remitente/imunologia , Adolescente , Adulto , Progressão da Doença , Feminino , Humanos , Interferon beta-1b , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Esclerose Múltipla Recidivante-Remitente/patologia , Prognóstico , Estudos Retrospectivos , Adulto Jovem
16.
Eur J Radiol ; 137: 109613, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33657476

RESUMO

PURPOSE: Pulmonary embolism (PE) in COVID-19 patients can play a key role in precipitating clinical conditions. We aimed to evaluate PE distribution on CTA and to investigate any possible association with D-dimer (DD), pulmonary stage of disease and prognosis. METHOD: COVID-19 patients of two affiliated Hospitals, undergone a CTA examination for PE suspicion, were retrospectively enrolled. Comorbidities, laboratory tests and clinical outcomes (hospitalization, discharge, death) were assessed. A parenchymal stage (early, progressive, peak, absorption) for lung involvement was assigned. RESULTS: A cohort of 114 patients (mean age 61 years; 26.3 % females) with severe COVID-19 pneumonia were evaluated. At last follow-up 25 (21.9 %) were hospitalized, 72 (63.2 %) discharged, 17 (14.9 %) dead. Eighty-eight patients (77.2 %) had at least one comorbidity, being cardiovascular ones the most frequent (44.7 %). CTA revealed PE in 65 patients (57 %), with concomitant pulmonary trunk and/or main arteries involvement in 16.9 %. PE defects were ubiquitous in 18.5 % of cases. The predominant parenchymal stages were the progressive (24.6 %) and peak (67.7 %). DD levels showed a significant correlation with PE occurrence and extent in pulmonary branches, despite anticoagulant therapies; trend of correlation with pulmonary stages was also noted. CONCLUSIONS: PE is a frequent complication in severe COVID-19 patients, particularly during central parenchymal stages and despite ongoing anticoagulant therapy. CTA and DD levels play a crucial role in the assessment of suspected PE, despite anticoagulant therapies, along with proper information about lung involvement extent.


Assuntos
COVID-19 , Embolia Pulmonar , Feminino , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Embolia Pulmonar/diagnóstico por imagem , Embolia Pulmonar/epidemiologia , Estudos Retrospectivos , SARS-CoV-2
17.
Astrophys J ; 913(1)2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-34646050

RESUMO

Since its launch, the Alpha Magnetic Spectrometer-02 (AMS-02) has delivered outstanding quality measurements of the spectra of cosmic-ray (CR) species ( p ¯ , e ±, and nuclei, 1H-8O, 10Ne, 12Mg, 14Si) which resulted in a number of breakthroughs. One of the latest long-awaited surprises is the spectrum of 26Fe just published by AMS-02. Because of the large fragmentation cross section and large ionization energy losses, most of CR iron at low energies is local and may harbor some features associated with relatively recent supernova (SN) activity in the solar neighborhood. Our analysis of the new AMS-02 results, together with Voyager 1 and ACE-CRIS data, reveals an unexpected bump in the iron spectrum and in the Fe/He, Fe/O, and Fe/Si ratios at 1-2 GV, while a similar feature in the spectra of He, O, and Si and in their ratios is absent, hinting at a local source of low-energy CRs. The found excess extends the recent discoveries of radioactive 60Fe deposits in terrestrial and lunar samples and in CRs. We provide an updated local interstellar spectrum (LIS) of iron in the energy range from 1 MeV nucleon-1 to ~10 TeV nucleon-1. Our calculations employ the GALPROP-HELMOD framework, which has proved to be a reliable tool in deriving the LIS of CR p ¯ , e -, and nuclei Z ⩽ 28.

19.
Phys Rev Lett ; 105(23): 231601, 2010 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-21231449

RESUMO

Within the functional renormalization group approach we study the effective quantum field theory of Einstein gravity and one self-interacting scalar coupled to N(f) Dirac fermions. We include in our analysis the matter anomalous dimensions induced by all the interactions and analyze the highly nonlinear beta functions determining the renormalization flow. We find the existence of a nontrivial fixed point structure both for the gravity and the matter sector, besides the usual Gaussian matter one. This suggests that asymptotic safety could be realized in the gravitational sector and in the standard model. Nontriviality in the Higgs sector might involve gravitational interactions.

20.
Mult Scler ; 16(1): 45-54, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20028706

RESUMO

Previous studies have shown a preferential loss of grey matter in fronto-temporal regions in patients with multiple sclerosis. Studies of correlates of disease severity are more controversial, because some studies have suggested an association between sensorimotor cortex atrophy and Expanded Disability Status Scale score, while others did not find such a correlation. The objective of this study was to assess the correlation of regional loss of grey matter and white matter with indexes of clinical and radiological severity in relapsing-remitting multiple sclerosis, including the Expanded Disability Status Scale and lesion load. Correlations between Expanded Disability Status Scale, lesion load and disease duration were assessed in 128 patients with relapsing-remitting multiple sclerosis (Expanded Disability Status Scale range 1.0-6.0) using optimized voxel-based morphometry. Bilateral loss of grey matter in sensorimotor cortices was correlated with Expanded Disability Status Scale, and tissue loss also involved adjacent white matter, extending along pyramidal tracts to the brainstem. Increasing lesion load was correlated with loss of deep grey matter and white matter. No specific region of grey matter or white matter showed a significant correlation with disease duration. These findings support the hypothesis that motor neuron involvement plays a major role in the progression of physical disability. Lesion load accrual affects mainly highly interconnected subcortical structures, while disease duration has a less significant impact on brain atrophy, probably owing to the inter-subject heterogeneity of the clinical course of the disease.


Assuntos
Encéfalo/patologia , Esclerose Múltipla Recidivante-Remitente/patologia , Adolescente , Adulto , Mapeamento Encefálico , Análise por Conglomerados , Interpretação Estatística de Dados , Avaliação da Deficiência , Feminino , Lateralidade Funcional/fisiologia , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Adulto Jovem
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