157 The fourth, using a multistage design of discovery (479 cases

157 The fourth, using a multistage Temsirolimus molecular weight design of discovery (479 cases, 2937 controls) and targeted replication (6666 cases, 9897 controls) samples, identified one genome-wide significant

SNP in the zinc-finger protein transcription factor ZNF804A gene,158 but only in the meta-analysis including the original sample. One independent replication attempt supported the association of ZNF804A, and showed that expression was increased from the associated haplotype.159 Three substantially larger GWAS of schizophrenia were published in 2009, in the SGENE+ sample160 (multiple European sites, 2663 cases/13498 controls), the International Schizophrenia Consortium (ISC) sample161 (multiple Inhibitors,research,lifescience,medical European sites, 3322 cases/3587 controls) and the Dovitinib manufacturer Molecular Genetics of Schizophrenia (MGS) sample162 (multiple US sites, Inhibitors,research,lifescience,medical European ancestry: 2681 cases/2653 controls; African ancestry: 1286 cases/973 controls), analyzed both separately and together. The one region of the genome with significant overlap in signals from the 3 studies was the MHC region on chromosome 6p21.3-p22.1, site of some of the earliest genetic

evidence in schizophrenia discussed above. Inhibitors,research,lifescience,medical The SGENE+ sample detected significant association with several markers spanning the MHC region, as well as signals upstream of the neurogranin (NRGN) gene on 11q24.2 and in intron four of the transcription factor 4 (TCF4) gene on 18q21.2. The ISC sample detected association in ~450 SNPs spanning the MHC region and the myosin XVIIIB (MY018B) gene on 22q and supported ZNF804A. The MGS Inhibitors,research,lifescience,medical sample did not detect any individual genome-wide significant signals, but detected signals in the range of 10-5-10-7 in the CENTG2 gene (reported deleted in autism cases163) on chromosome 2q37.2 and JARID2 (the gene adjacent to DTNBP1) in Europeanancestry subjects, and in ERBB4 and NRG1 Inhibitors,research,lifescience,medical in AfricanAmerican subjects. Meta-analysis of data from all European-ancestry MGS, ISC and

SGENE samples detected genome-wide significant association signals for 7 SNPs spanning 209 Kb of the MHC region. LD is high between the 7 SNPs and extends over a region of 1.5 Mb on chromosome 6p22.1, making it difficult to determine if the signal is driven by one or many genes. The genic content of this region is not limited to histocompatibility loci, and also includes genes involved in transcriptional regulation, DNA repair, chromatin structure, G-protein-coupled-receptor signaling Brefeldin_A and the nuclear pore complex. Meta-analyses of schizophrenia linkage and association data The strongest linkage meta-analysis approach ranks 30 cM bins of the genome from most positive to least positive for each study, and then sums the ranks for each bin. Significance levels are calculated by simulation, and this method can identify regions of the genome where modest positive results occur across many studies.

12) in patients with wild-type K-ras (114) In contrast, K-ras s

12) in patients with wild-type K-ras (114). In contrast, K-ras status did not significantly influence response in a Belgian study using cetuximab prior to and concurrent with capecitabine and (97). In a pooled analysis of 2 phase II studies, KRAS mutations were detected in 20 of the 82 patients (24.4%). 3-year DFS was higher i.e., 86.6% versus 75.0% Inhibitors,research,lifescience,medical but not significantly improved for patients receiving cetuximab with chemoradiation

and chemoradiation alone, The lack of difference in outcomes remained whether assessed in KRAS wild-type or mutant patients (115). Some authors have pointed out that there may be an optimal sequence of chemotherapy, biological agent and radiation if we are Inhibitors,research,lifescience,medical to avoid the potential for antagonism (58). The lack of additive effect can be explained if the addition of other agents

leads to an over targeting of one target (? the endothelial cells within the tumour); if the novel agent leads to cell-cycle arrest protecting cells from the effects of 5-FU; if drug concentrations are suboptimal because of the low weekly doses being ineffectual; if there are antagonistic drug-drug interactions which could be more prominent in the presence of radiation [we know from the PACCE and CAIRO (23,116) trials that combinations of cetuximab and chronic myelocytic leukemia bevacizumab with 5-FU and oxaliplatin are antagonistic]; if biological agents and the Inhibitors,research,lifescience,medical apoptotic response and hence secondary Inhibitors,research,lifescience,medical immune phenomena are modified—after all neither bevacizumab nor cetuximab appear effective in the adjuvant setting; finally a heightened inflammatory response may simply attract more stem cells and actually assist repair. The multifactorial nature of these potential problems is obvious and poses a significant challenge if we wish to continue this form of biological, chemotherapeutic and radiation integration. However,

some authors claim that target guided individualisation Inhibitors,research,lifescience,medical of treatment according to molecular markers can be successfully achieved (117). A large multinational randomised phase II study EXPERT-C (NCT00383695) has compared neoadjuvant therapy comprising combination chemotherapy (oxaliplatin and capecitabine), with or without cetuximab followed by chemoradiotherapy with capecitabine with or without cetuximab in 164 patients (56). In the EXPERT-C trial, retrospective molecular analysis for KRAS/BRAF Drug_discovery was successfully performed in 149 patients, of whom 90 (60%) were wild type. The pCR rate was not significantly higher with the addition of cetuximab to preoperative chemotherapy and CRT either for the group with locally advanced rectal cancer as a whole (18% versus 15% respectively), nor for KRAS wild-type – although this percentage is diluted by the fact that some samples achieving pCR were not available for Kras testing. Interestingly DFS in the selected KRAS wild-type group who received cetuximab was higher (56).

It has been reported that several nanomaterials, such as SiO2, Ti

It has been reported that several nanomaterials, such as SiO2, TiO2, cobalt-chrome (CoCr) metal particles, and carbon nanotubes, interact with structural elements of the cell, with an apparent binding to the cytoskeleton and in particular the tubulins [79, 80]. In this setting, some evidence in vitro demonstrated that carbon nanotubes mimic or interfere

with the cellular microtubule system, thereby disrupting the selleck products mitotic spindle apparatus and Trichostatin A leading to aberrant cell division [81–83]. Inhibitors,research,lifescience,medical In particular, the perturbation of centrosomes and mitotic spindles dynamics caused by these nanoparticles results in monopolar, tripolar, and quadripolar divisions, that, in turn, could determinate aneuploidy [78], an event closely linked to the carcinogenesis. Tsaousi and collaborators found Inhibitors,research,lifescience,medical that alumina ceramic particles increase significantly in micronucleated binucleate cells [84], which is considered a morphological marker of mitotic catastrophe [78]. Interestingly, this increase was much greater after exposure of primary human fibroblasts to CoCr metal particles, suggesting that these nanoparticles are particularly efficient in

affecting the mitotic machinery [84]. Apparently, the genotoxic effect of CoCr nanoparticles is Inhibitors,research,lifescience,medical size dependent. Indeed, CoCr nanoparticles induced more DNA damage than microsized ones in human Inhibitors,research,lifescience,medical fibroblasts (Figure 3). In fact, the mechanism of cell damage appears to be different after nano- or microparticles exposure. The enhanced oxidative DNA damage by the microparticles may result from a stronger ability of large particles to activate endogenous pathways of reactive oxygen

species formation, for example, involving NADPH oxidases or mitochondrial activation. It also suggests that the observed genotoxic effect of the nanoparticles in the Inhibitors,research,lifescience,medical comet assay and the micronucleus assay (i.e., stronger aneugenic effect) is due to mechanisms other than oxidative DNA attack. A different mechanism of DNA damage by nanoparticles and microparticles is further suggested by measures of DNA damage Dacomitinib from the comet and micronucleus assays. The comet assay revealed more damage in nanoparticle-exposed than in microparticle cells. In contrast, the micronucleus assay revealed slightly less centromere-negative micronuclei in nanoparticle exposed than in microparticle-exposed cells. This assay measures clastogenic, that is, double strand breakage events. Although some micronuclei in nanoparticle-exposed cells might not have been seen as a result of inhibition of cell division from greater cytotoxicity, these results point to a greater complexity of DNA damage caused by exposure to nanoparticles compared to microparticles [85].

It is the authors’ guess that behavioral speed represents an aggr

It is the authors’ guess that behavioral speed represents an aggregate of many different cellular, structural, and functional changes that, occur in the brain with age, and that the particular nature of the changes that have aggregated to result, in slowing could vary considerably from individual to individual. We believe that a focus on a single mechanism to find the underlying cause of age-related decline in speed will be less successful than

a “multiple cause” approach to understanding the indices of neural health with age. The “common cause” view that, sensory Inhibitors,research,lifescience,medical function provides a quick measure of global neural health6 may be even more difficult to isolate. There is evidence that there is a decreased amplitude of the this hemodynamic response in visual cortex with age, although the summation properties of the hemodynamic response do not differ across age.77,78 Inhibitors,research,lifescience,medical On the other hand, the sensory cortex appears to be more resistant to the age-related volumetric decreases compared with other areas of the brain,41 which is hard to reconcile Inhibitors,research,lifescience,medical with the sensory function hypothesis. It, is also difficult to reconcile the simplicity of the behavioral hypothesis with the complexity and distribution of the neuronal correlates of sensory function. In sum, there

is a great need for large studies that examine the neurobiological underpinnings of single-mechanism accounts of cognitive aging. It, is likely that, a multitude of accrued cerebral insults that differ widely among individuals could account, for this relationship. Age-related declines in executive function and long-term Inhibitors,research,lifescience,medical memory Given the volumetric decreases that occur reliably with age in prefrontal cortex, and the finding that shrinkage in this area predicts

poor cognitive performance,41 the linkage between behavioral declines in working memory, inhibition, task-switching, and long-term memory and prefrontal dysfunction is well Inhibitors,research,lifescience,medical established. The rather straightforward picture these becomes more confusing, however, when one examines the relationship of activation patterns in prefrontal cortex to executive function, as there is evidence for increases and decreases in activation in frontal areas with age and evidence for various age-related forms of dedifferentiation, such as contralateral recruitment, unique recruitment, and substitution. Moreover, there is considerable variability Batimastat across studies on specific areas of frontal activation as a function of age. Nevertheless, there can be little doubt that, much of the decline in executive processes observed in older adults is due to frontal dysfunction. Another important, distinction between behavioral and ncuroscience research on aging and memory is that cognitive aging researchers tend to refer to speed of processing and working memory as “cognitive resources” accounting for age-related decline.

27 Neither of the anatomic

MRI studies that reported puta

27 Neither of the anatomic

MRI studies that reported putamen volumes detected significant diagnostic group differences.22,32 However, studies of secondary ADHD suggest that the putamen selleckchem lesions can contribute to ADHD symptomatology. In a study of 76 children with severe closed head injury, those who developed secondary ADHD were significantly more likely to demonstrate lesions in the right putamen.33 likewise, children Inhibitors,research,lifescience,medical with focal strokes and ADHD symptoms were significantly more likely to have involvement of right ventral putamen.34 The caudate, putamen, and nucleus accumbens receive efferents from the entire cerebral cortex. This impressive convergence of information is then processed and emerges from the output, nuclei of the basal ganglia, which, in primates, are the internal segment, of the globus pallidus and the substantia nigra pars reticulata. However, the volume of the latter

cannot be reliably measured with current MRI Inhibitors,research,lifescience,medical parameters, and the size of the globus pallidus can only be measured as a unit (internal and external segments together), Inhibitors,research,lifescience,medical and then only with difficulty. Still, this region was found to be significantly reduced in size in boys with ADHD,22,32 although these two studies differed in side of the larger difference (left or right). Globus pallidus volume differences in girls with ADHD did not survive Inhibitors,research,lifescience,medical covariance for total cerebral volume and IQ.31 A report of two cases of severe iatrogenic ADHD presumed to have been caused

by traumatic amniocentesis at 17 weeks’ gestation found complete ablation of right caudate, putamen, and globus pallidus in both.35 Cerebellum An early Inhibitors,research,lifescience,medical computed tomography study found a trend toward greater cerebellar atrophy in adults with a prior history of hyperkinetic minimal brain dysfunction.36 In a quantitative MRI study of 112 subjects, the volumes of the cerebellar hemispheres were found to be significantly smaller in ADHD boys.22 In a follow-up study within the same sample, the cerebellar vermis as a whole, and particularly the posterior-inferior lobules (lobules VIII to X) were found to be significantly smaller in ADHD.37 Smaller lobules VIII-X were independently replicated in boys with ADHD,38 and in girls with ADHD31 Batimastat where the posteriorinferior cerebellar vermis was the only structure that was rigorously replicated, with a comparable standardized Vismodegib hedgehog effect size (d=0.66 in boys, d=0.63 in girls). Recently completed automated analyses of brain anatomy in 152 children and adolescents with ADHD and 139 age- and sexmatched controls revealed highly significant global decreases in overall cerebral volume in patients, which were statistically comparable in all four lobes, and which were statistically more prominent only in cerebellum.

As far as we know, the only data about gene therapy on man concer

As far as we know, the only data about gene therapy on man concern one case of Mucopolysaccharidosis II (18), three selleck chemicals Sorafenib patients affected by Mucopolysaccharidosis I (19) and some patients suffering from Gaucher disease (20). Considering the researches carried out so far, we think that many problems have still to be solved before proving unequivocally effectiveness and safety of this treatment in man: a patient’s optimal age for undergoing gene therapy, the possible development of immunologic reactions,

the capability to modulate both levels and duration of enzyme activity, the need of finding a specific ablative regimen for BMT Inhibitors,research,lifescience,medical approach. Conclusions As above reported, therapeutic approaches toward finding treatment options fit to face the underlying causes are many: so far positive results, unanimously Inhibitors,research,lifescience,medical accepted by the international scientific community, have been obtained only for few lysosomal disorders. However, LSDs, though quite rare diseases, are getting more and more investments from private enterprises interested in orphan drug production. Inhibitors,research,lifescience,medical The above mentioned fact lets us hope that, in a near future, the natural development of more and more diseases will be influenced and thus modified.
McArdle disease or Glycogenosis type V is an autosomal recessive metabolic disorder caused by a deficiency of the muscle isoform of glycogen phosphorylase (myophosphorylase,

PYGM), the specific skeletal muscle enzyme that initiates glycogen breakdown. Since the first clinical description by Brian McArdle in 1951, several patients have been identified worldwide and significant advances have been made in the study of molecular genetics of the disease. Inhibitors,research,lifescience,medical Molecular heterogeneity has been demonstrated by the identification to date of more than 65 mutations in the PYGM gene. In this paper, we will present an update on the mutations Inhibitors,research,lifescience,medical reported to date in the PYGM gene. Keywords: McArdle disease, Glycogenosis type V, PYGM gene Clinical data McArdle disease or Glycogen Storage Disease

type V (GSD-V; MIM # 232600) is the most common muscle glycogenosis caused by the deficiency muscle glycogen phosphorylase (myophosphorylase, EC 2.4.1.1) activity. GSD-V is clinically characterized by exercise intolerance with premature fatigue, cramps, myalgia, moderate to high levels of serum creatine kinase (CK) at rest, and by episodic myoglobinuria (1). All McArdle patients experience Batimastat the so-called ‘second-wind’ phenomenon, characterized by the ability to resume exercise with less difficulty, after following a short period of rest at the first appearance of fatigue (2). A subset of patients develops fixed weakness and wasting with aging, HTS indicating phenotypic variability). The diagnosis is based on the clinical phenotype and DNA analysis is suggested as the first choice in the diagnostic approach.

Reliability among the three independent raters was high (weighte

Reliability among the three independent raters was high (weighted Kappa

=0.72 for categories 0-30, 31-39, 40-50) suggesting that this cluster of judgments might be useful to highlight and quantify important, issues during the protocol stage of an RCT. Table I. Average score of three raters for each one of the domains of the RCT protocol. We recognize that validity Inhibitors,research,lifescience,medical is a more problematic issue, as this does depend on the rater’s perspective, but, work is ongoing involving raters from very different backgrounds. In any case, we concur that, consideration of these domains is useful9 and suggest that the Pragmascope is one practical way of doing this. Discussion The world of RCTs has changed remarkably in the last 10 years. Systematic reviewing of trials, Inhibitors,research,lifescience,medical now industrially undertaken through initiatives like the Cochrane Collaboration,20 has highlighted issues with poor design and inconsistent reporting. These systematic reviews are potent to guide care but, are undermined by trial evidence that is difficult or impossible to apply in the real world. For mental health, studies of increasing pragmatism are now being designed and undertaken.21-23 Such pragmatic, real-world, practical design can be dovetailed within explanatory Inhibitors,research,lifescience,medical studies or sit independently. With maintained systematic reviews guiding practice,21 transparent priority setting for research funding for evaluative research,3 and the push towards

defining core out come Brefeldin A measures of agreed relevance in trials,24 a great, increase in pragmatic trial activity is likely. Of course explanatory trials have an important place in the portfolio of research, but. the rigorously undertaken but highly pragmatic Inhibitors,research,lifescience,medical trial will give us the opportunity to learn much more about, the real effects of the potent, treatments we give. Appendix. The Pragmascope (Figures 2) Explanation: This tool is based on ten domains described in the development of the Pragmatic-explanatory continuum indicator summary (PRECIS).9 It can be used to assess applicability Inhibitors,research,lifescience,medical of results from

any given randomized controlled trial. Instructions: … Appendix. The Pragmascope (Figures 3) Acknowledgments We would like to thank Dr K. Thorpe for consideration of our rating tool, and Dr B. Park for help calculating Kappa. Contributor Information GSK-3 Graeme Tosh, Psychiatrist, East Midlands Workforce Deanery, Nottingham, UK. Karla Soares-Weiser, Director, Enhance Reviews Ltd, Oxford, UK. Clive E. Adams, Professor, Institute of Mental Health, University of Nottingham, UK.
An the context of evidence-based medicine,1 randomized control-group trials (RCTs) are considered to be the decisive level of scientifically proven evidence as far as therapeutic aspects are concerned.2 Vorinostat clinical trial Placebocontrolled trials, especially for certain psychiatric indications, are ranked higher in terms of evidence than active control-group studies.

Botswana is one of the first African countries to become signator

Botswana is one of the first African countries to become signatories to the Framework Convention on Tobacco Control (FCTC). Botswana signed FCTC in June 2003 and ratified in 2005. Prior to this development, Botswana had enacted her first tobacco control legislation, the Control of Smoking Act (CSA) in 1992. The main focus of the act is on controlling Environmental supplier Nilotinib Tobacco Smoke in enclosed public and workplace, educational institutions and hospitals as well as to ban tobacco advertising. To date, the country has by far successfully implemented several key aspects of the

FCTC guidelines such as smoke free places, a ban on advertising and promotion of tobacco products, and sale to minors. However, the are no systems in place to check compliance [25]. The results of this study demonstrated that male teachers had a significantly higher prevalence of tobacco smoking than their female colleagues (10.8% vs 0.4%, p<0.001). Similar results have been found in other studies conducted in Japan where, only 3.1% and 44.7% of female and male teachers respectively, were smokers [26], and in Syria where 12.3% of female and 52.1% male

teachers were smokers [22]. In addition, 94% of smoking teachers in Bahrain were male teachers [14]. Comparably, other studies have also reported that smoking was higher among male than female teachers [9,16,27]. Interestingly, the results of studies conducted among primary school teachers in Belgaum City, India [15] and secondary school teachers in Yemen [8], indicated that female teachers in these studies did not smoke. Low prevalence of smoking among female teachers could be because traditionally it is a taboo for women to smoke. It has been suggested

that there are few female smokers than males especially in developing countries which could probably be related to social norm that has been long formed in many societies [9]. In this study, cigarette smoking was found to be associated with marital status (p=0.001). Similar findings were reported by Malay secondary school teachers [9]. School level (p=0.002) and body mass index (p=0.027) were also significantly associated with smoking among school teachers in Botswana. However, age, education level, number of children less than six years, length of employment, working hours and number of students taught were not significantly Batimastat associated with smoking. Smokers in this study indicated that they have been smoking for periods ranging from a year to 31 years with an average smoking duration of 8.62 years, smoking between one to 20 cigarettes a day. The average number of cigarettes smoked was 5.6 per day. The results also show that 5.3% of teachers in the study were ex-smokers having smoked for one to 27 years with average smoking years of 7.83 years. Various strengths and limitation were found for this study.

g shelters, soup kitchens, syringe exchange programs, etc ) shou

g. shelters, soup kitchens, syringe exchange programs, etc.) should be formally partnered with the end-of-life care system. Participants articulated how the trust developed between these agencies and homeless populations helped to mediate access to a range of other services (e.g., primary care, specialists, etc.) and could perform a similar function

in the context of end-of-life care. kinase inhibitor Volasertib Furthermore, participants reported that these agencies, and especially trusted staff, were able to monitor changes in health status over time due to their selleck Calcitriol sustained contact with this population and mediate access to health and end-of-life care services. For example: “We work together Inhibitors,research,lifescience,medical at three Inhibitors,research,lifescience,medical sites. Because many of our patients that we have [in the hospice] have been known to the other two sites, there’s kind of a family. In that way, we help each other and we communicate

with each other. As far as other facilities go, we use what’s out there in the community. Our patients may be known to some community health centers. (Nurse)” Participants felt that, where partnerships were weak or did not exist, they needed to be developed. Several participants also noted that third-party advocates (e.g., patient navigators) could play a role in Inhibitors,research,lifescience,medical acting as liaisons between community agencies and the end-of-life care system to strengthen these partnerships. For example: It would be helpful to have like individuals Inhibitors,research,lifescience,medical who serve as bridges between the [health and social services] systems. Usually, people don’t want a system. They want a person that they can call so, the doctor or the health care team in the hospital would prefer that there is a person that they can call to help them out rather than saying “These are the steps that you do.”

I think that people are the key to building bridges. (Physician) Strengthening training for end-of-life care professionals Participants reported that increased training was needed to strengthen the capacity of healthcare professionals to address the complex and diverse needs of homeless Inhibitors,research,lifescience,medical populations at end-of-life (e.g. pain and symptom management, substance use, etc.). Participants noted that, while they valued Cilengitide the clinical expertise of healthcare professionals, clinicians often lacked experience in areas such as mental health and substance use that limited their effectiveness and openness to best practices. One participant remarked: “When you’re trained in your profession, you’re trained in a certain way. If harm reduction wasn’t in your training, you’re not going to know anything about it. How can you expect somebody to embrace that with open arms if they know nothing about it? (Harm Reduction Specialist)” Participants acknowledged that they needed to strengthen their training in these areas, as well as provide training opportunities for students.

The devices were exposed to the solutions in a random order The

The devices were exposed to the solutions in a random order. The target solution was sucked from the beaker into the microfluidic cell after which the flow was stopped and the measurements were performed under stagnant conditions at room temperature. The measurement was started immediately after exposure to the liquid. Each exposure continued for approximately 10 min using the add to your list liquid gate as described previously.A standard Keithley 4200 semiconductor characterization system (Keithley Instruments BV, Gorinchem, The Netherlands) equipped with eight source measurement units was used for the electrical characterization of the device during exposure. A 50 mV source-drain bias was applied and VGS was applied such that the device is operated in depletion mode in the linear regime (VSD VGS). The drain current (ID) was measured while the gate potential (VGS) was swept. This can be applied either via the back gate or the liquid gate. From these characteristics the threshold voltage (VT) was determined.To study the influence of the liquid medium in contact with the SiNW on the device characteristics 1,4-dioxane (anhydrous, 99.8%, Sigma-Aldrich Chemie B.V., Zwijndrecht, The Netherlands) (��r = 2.25) and de-ionized water (��r = 80.1; �� = ~20 k�� cm) were used as solvent because they mix in all ratios and make it possible to change the dielectric constant gradually in the range of 2�C80. They were mixed as described by ?kerl?f et al. [37] to obtain mixtures with a range of dielectric constants. To adjust the electrical conductivity, tetramethylammonium chloride (��98%, Sigma-Aldrich Chemie B.V., Zwijndrecht, The Netherlands) was dissolved in the solvent mixtures where mentioned. The conductivity and pH of the solutions were measured using a Metrohm 712 Conductometer and a Metrohm 827 pH lab meter, respectively (Metrohm equipment was purchased from Applikon Analytical B.V., Schiedam, The Netherlands).3.?Results and DiscussionFirst the devices were exposed to water and the electrical characteristics were determined using the back gate and the liquid gate. The results of this comparison are discussed in Section 3.1. Subsequently, the devices were exposed to water�Cdioxane mixtures with a range of dielectric constants and the electrical characteristics were determined using liquid gating via an Ag/AgCl electrode (Section 3.2). In addition, the conductivity of some mixtures was adjusted to obtain solutions with similar conductivities.3.1. Back Gate vs. Liquid Gate in De-Ionized WaterFigure 2 shows a schematic representation of the back-gated and liquid-gated situation and the capacitances that are present. In both cases the Cliquid was present, although it has a different value for
Relaxation times define the rate of spin magnetic equilibrium recovery in nuclear magnetic resonance (NMR) [1,2]. For each tissue, several relaxation times can be defined.