3D). To corroborate the suggestion the mechanism of action, we explored some hallmarks of apoptosis during a 24 h HL-60 cell exposure to the α-santonin derivatives (2, 3 and 4). For this purpose, HL-60 cells treated with the lactones 2, 3, and 4 were stained with AO/EB in order to discriminate cells undergoing necrosis or selleck kinase inhibitor apoptosis. The compounds 2, 3 and 4 were able to reduce the number of viable cells at higher concentrations [2 μM (77.3 ± 1.5%, 70.7 ± 0.1% and 70.1 ± 2.1%)] and to expand the apoptosis level (20.5 ± 1.6%, 26.6 ± 0.4% and 26.4 ± 1.5%), respectively (p < 0.05). On the other hand, compound 4 was the single concentration capable to decrease the number of viable cells at 1 μM (84.1 ± 1.5%) when compared to negative control (92.5 ± 0.5%) (p < 0.05, respectively). At lowest concentrations, compounds 2, 3 and 4 also induced apoptosis (14.0 ± 1.1% and 11.8 ± 0.6% and 13.6 ± 1.6%, respectively) ( Fig. 4, p < 0.05), though in lower levels. The positive control (Dox, 0.6 μM) reduced viable cells (60.0 ± 7.3%) and increased apoptosis (36.2 ± 4.8%).

When examined under light microscopy, control cells exhibited a typical non-adherent and round morphology, while derivatives-treated cells displayed chromatin condensation, nuclear fragmentation and shrinking in all concentrations tested (Fig. 4). Dox also induced cell reduction and nuclear disintegration. Phosphatidylserine externalization was Selleck Doxorubicin determined using Annexin V test as a marker of apoptosis. Annexin V, a 35 kDa Ca2+ phospholipid-binding protein, binds to the phosphatidylserine Adenosine on the outer layer of the plasma membrane with a high affinity due to loss of polarity whereas propridium iodide (PI) bind to cells that lost membrane integrity (Krysko et al., 2008). After 24 h exposure, compounds 2, 3 and 4 at 2 μM were able to reduce cell viability (90.2 ± 1.5%, 89.5 ± 1.6% and 86.7 ± 2.7%), to induce early (7.5 ± 0.8%, 7.6 ± 1.0% and 8.7 ± 0.7%) and late apoptosis (0.8 ± 0.1%, 0.6 ± 0.1% and 0.7 0.2%) and necrosis

(1.6 ± 0.3%, 1.4 ± 0.1% and 1.6 ± 0.4%) on leukemia cells in comparison with control (92.5 ± 0.6%, 5.9 ± 1.0%, 0.2 ± 0.1% and 0.4 ± 0.1%, respectively) (Fig. 5A, p < 0.05). Meanwhile, Dox-treated tumor cells also revelaed cell viability decreasing (50.5 ± 0.2%), high levels of early apoptosis (47.5 ± 0.3%) and necrosis (1.6 ± 0.1%) following 24 h of treatment (p < 0.05). The main characteristic of cell undergoing apoptosis is the activation of caspases. The caspases can be categorized into initiator (8, 9 and 10) and executing caspases (3, 6 and 7) (Hanahan and Weinberg, 2011). At highest concentration, the compounds 2, 3 and 4 reduced cell viability (83.2 ± 5.2%, 83.4 ± 6.6% and 76.3 ± 8.5%) and increased the number of early (7.3 ± 2%, 5.8 ± 2.5% and 9.1 ± 4.1%) and late apoptosis cells (4.5 ± 0.8%, 5.

An ideal biopsy needle should minimize pneumothorax and bleeding complications and maximize the tissue specimen obtained. In our practice, we use automated cutting needles to obtain sufficient tissue amount free of crush injury for histologic evaluation. Two types of automated

cutting core biopsy needles have been used. They include side-notch needle and end-cut needle. Choice between these two types is generally a matter of preference and availability. The end-cut GSK2118436 order design has several advantages. Most importantly, a full cannular width of tissue is obtained as the entire lumen and almost the whole length of advancement of the needle within the lesion is used to enclose the specimen. In the side-notch biopsy needle, the actual length of the side notch (i.e. specimen) is shorter than the advancement of the needle as only part of the needle lumen (i.e. the volume of the notch) is used

to have tissue [26]. Yet another distinction between the Trametinib in vitro types of needles is related to the technique used for obtaining the biopsy as coaxial and single shaft (non coaxial). Each technique has certain advantages compared to the other. However, there is no proof that any type of technique is superior to other types in terms of diagnostic yield and complication rate [8]. Using the coaxial technique, the needle will be more stable in the chest wall and multiple samples can be obtained with a single pleural puncture which helps in improving the diagnostic yield and reducing the risk of pneumothorax especially with smaller diameter needle [27]. The advantage of the single needle is that it is more flexible. This may help in guiding the needle to the correct location. The continued refinements in needle design appear to be potential for improved

sensitivity and specificity for both benign and malignant diagnosis [28] and [29]. After consideration of the patient history and indications for the biopsy, an informed consent is obtained from the patient and the family. The consent should include the discussion of the potential risks and benefits in details. The baseline chest CT images are carefully reviewed and the procedure is planned based on the size and location of the lesion, availability of imaging systems, and local expertise. The needle path is PLEKHB2 chosen considering straight pathway from the skin to lesion. Ideally, the needle should cross the pleura at a 90-degree angle rather than at an oblique angle. The pathway should avoid transversal of bullae, vessels and bronchi. The interlobar fissures are avoided usually as the more pleural surfaces that are crossed, the higher the risk of pneumothorax. In case of more than one lesion is present, the more peripheral lesion is chosen over a deep lesion because less lung will be traversed, decreasing the risk of complications.

The lesser-known group concerns the asymptomatic

European adult patient. We are presenting a single center case series of 6 European adult people with asymptomatic moyamoya disease, suspected through TCCS and confirmed by DSA, followed-up in medical treatment. During a time period of three years we collected a series of six patients (5 female and 1 male, mean age 29.16 + 8.45 years) with a neurosonological suspicion and a neuroradiological diagnostic confirmation of moyamoya type arteriopathy. All patients underwent to neurosonological examination for episodic not related symptoms, like dizziness, or for a screening purpose in a family history of cerebrovascular atherosclerotic accidents. Besides the neurosonological examination with ultrasound study of the cerebroafferent vessels and of the intracranial arteries by TCCS, all patients underwent brain MRI and MRA and DSA and blood sampling and other investigations learn more for differential diagnosis of immunological or infectious etiology. Diagnosis was made according to the approved criteria [Research Committee on Spontaneous Occlusion of the Circle of Willis Talazoparib (moyamoya disease) in Japan] [7]. TCCS was performed as a basal evaluation and with contrast agents for the evaluation of intracranial vessels in Power Modulation or Pulse Inversion.

Ultrasound perfusional study was also performed but the data were not analyzed, because of the bilateral involvement in most patients and the lesser reliability of PCA territory for a comparison, due to the collateral circulation. MRI and DSA were analyzed according to the Ministry of Health and Wellness of Carteolol HCl Japan criteria [7]. The mean follow-up was 1.8 years and it was both clinical and neurosonological–neuroradiological (with MRI). All patients were followed-up in

at least 3 control visits, at 3 months from the diagnosis, at 6 months and at 12–18 months. The main features of the six patients are illustrated in Table 1. All patients had a bilateral involvement in the intracranial circulation and all but one had a diagnosis of moyamoya disease/phenomenon, because of the absence of the well-known risk factors and associated conditions; one patient had a unilateral involvement, and therefore the diagnosis was a moyamoya syndrome. There is an evident prevalence of the female sex (female to male ratio 5). TCCS study was performed by an experienced neurosonologist both without and with ultrasound contrast agents (SonoVue®) in all patients and no side effects from the procedure were reported. Neuroradiological examination, first brain MRI and intracranial MRA, and second DSA, were performed because of the suspicion of moyamoya arteriopathy and confirmed it. There was not any brain tissue abnormality suggesting acute cerebrovascular event in all examined patients, nor in basal MRI study and in control examinations.

H3.3/H2A.Z hybrid nucleosomes localized to the TSS of active genes, at sites that have previously been characterized as nucleosome depleted regions (NDRs). Upon modulating the salt concentration used in the nucleosome isolation, it was discovered that H3.3/H2A.Z nucleosomes are unstable PARP inhibitor in vivo, causing them to dissociate from the DNA during extraction, leaving behind a NDR. Although a crystal structure is not available for this double hybrid, in vitro characterization of the H3.3/H2A.Z

nucleosome’s stability by salt induced dissociation revealed only very small differences compared to the stability of the canonical nucleosome, resulting in a puzzling discrepancy between in vivo and in vitro results [ 20]. However, a recent investigation into a post-translational modification (PTM) found not on the histone tail, but at H3K122, in the center of the nucleosome core, suggests a plausible explanation that could neatly resolve this discrepancy [ 21••]. Acetylation at H3K122 disrupts the interaction between the histone core and DNA, destabilizing the nucleosome [ 22••]. Furthermore, it co-localizes with H3.3 and H2A.Z in vivo, leading to the compelling hypothesis that K122 acetylation on H3.3, which is absent Enzalutamide solubility dmso in the in vitro studies, may be responsible

for the destabilized H3.3/H2A.Z nucleosome in vivo [ 21••]. An alternative attractive explanation for the instability of the H2A.Z/H3.3 hybrid nucleosome

may lie with a newly characterized H2A.Z splice variant, H2A.Z.2.2 [ 23]. Due to its unique docking domain, this particular histone physically destabilizes the octameric core of the nucleosome. While it is unknown whether H2A.Z.2.2 co-localizes with H3.3 in the cell, the decreased stability observed in H2A.Z/H3.3 hybrid nucleosomes could be attributed to the splice variants. An additional key example of nucleosome conformation variability has also been documented for native CENP-A nucleosomes in vivo, which exhibit a surprising bi-stability across the human cell cycle, concurrent with cell-cycle regulated acetylation on K124, in the center of the CENP-A octameric core [ 24 and 25]. Thus, it click here is feasible that other histone variants display modification-dependent conformational oscillations that impact their inheritance and function in vivo. While nucleosomes have been shown to associate with specific locations within the genome, such as the localization of H3.3 and H2A.Z to TSS, the mechanisms underlying nucleosome positioning in the cell are still being debated. Both experimental and theoretical research have uncovered subtle structural motifs embedded within the primary sequence of DNA as a key component driving preferential nucleosome formation, albeit at subsaturating levels of histones [26 and 27].

It is well established that the prefrontal

cortex undergoes structural and also seemingly functional change with increasing age (see Grady, 2008 for review). Less established are effects on parietal cortex and Selleck Everolimus the right hemisphere white matter underlying these regions. However, it appears to be the case that older participants have significantly more activity in posterior parietal cortex whilst attending to an attentional cue (Jimura and Braver, 2010) and a general greater recruitment of these regions in other attention tasks (Grady, 2008). The authors propose that this age group is less efficient at utilizing attention, possibly as a result of loss of capacity (Jimura and Braver, 2010). Structurally, there is evidence of both cortical parietal atrophy (Bergfield et al., 2010) as well as age-related white matter hyperintensities in this region

(Murray et al., 2010). Results found here correspond well with these recent neuroimaging studies as we demonstrate the behavioural consequences of age related degeneration of attentional networks. The results outlined within this paper are important with respect to the groups studied here but beyond that the paradigm itself is a significant development. Our own previous research using a similar paradigm revealed that if task load is high enough even young healthy participants can miss items in the click here near periphery (Russell et al., 2004 see Lavie, 2005). Further adaptation of the basic method could be used to investigate attentional capacity across diverse groups such as those with left hemisphere damage or suffering from dementia, enabling the identification of the key brain regions and networks for integration of spatial and temporal components of attention. In conclusion, we have examined spatiotemporal attention processing capacity in two groups. The first (Experiment 1) consisted of patients with right hemisphere lesions, without neglect. Compared to next their healthily ageing counterparts,

these individuals suffer from a pathological loss of ability to discriminate simple stimuli even in the near periphery when they complete an unrelated task at screen centre. This loss is modulated by the amount of attention they must give the central task and temporally extends for a period of 850 msec. Secondly (Experiment 2), task modulations made it possible to examine the effects of healthy ageing on visual attention. Here we were able to show that an older group (mean age: 63 years) was as efficient as a much younger group when little attention was required at screen centre. However, they were greatly impaired across the visual field when they were required to allocate more attention centrally. They failed to discriminate simple letters and suffered from an AB of 450 msec.

The reaction mixture (20 μL) contained 1× dd-PCR master mix (Bio-Rad), 0.9 μM each primer, 1 μM probe and 1 μL template DNA. PCR amplification was carried out on a 2700 GeneAmp® PCR system (Applied Biosystems, Foster, USA). PCR was initiated at 95 °C for 10 min, followed by 40 cycles at 95 °C for 15 s and 60 °C for 90 s, and 1 cycle at 98 °C for 10 min. Data were obtained and analyzed using the QX100™ droplet reader (Bio-Rad) and QuantaSoft software

(Bio-Rad). The QuantaSoft program generates absolute Ibrutinib ic50 quantities per microliter-reaction mixture (a total of 20 μL-reaction volume) from given numbers of positive droplets and negative droplets. The obtained values were multiplied by 20 to calculate quantities in microliter-DNA extracts. qPCR was performed

using an Applied Biosystems 7300 system as previously described [9]. dd-PCR was used in order to determine the concentrations of the external DNA calibrators with multiple probe sites [9] for qPCR because it accurately provides absolute quantification of target DNA [3], [4] and [6]. The 25-μL reaction mixture contained 1× PCR buffer, 0.2 μL Ace-Taq (Genenmed, Seoul, Korea), 0.3 mM dNTPs mix, 0.25 μM each primer, 0.15 μM probe, 1× ROX (Invitrogen, Carlsbad, USA), 1× SYBR green I (Invitrogen) and 1 μL template DNA. PCR was initiated at 95 °C for 3 min, followed by 40 cycles at 95 °C for 15 s and 55 °C for 90 s. Two artificial DNA templates with multiple probe sites were developed as reference http://www.selleck.co.jp/products/erastin.html DNA templates for qPCR of the 10 groups [9]. The two artificial sequences (509 bp long) contain Omipalisib clinical trial the target DNA region (amplified by the primer pair), with additional

flanking 20-bp DNA regions at the both ends. Plasmids with the artificial DNA templates were used to construct standard curves. They were serially diluted 10-fold. The two technologies did not detect DNA at <10−8 dilution (equivalent to 8 copies μL−1 as measured by dd-PCR). The 10 standard curves constructed by qPCR over the 10-fold serial dilution series (10−5–10−8) showed a slope value of 3.39 ± 0.14 (R2 = 0.99 ± 0.01), corresponding to a PCR efficiency of 97%. In order to compare the quantitative limits of detection, linearity and PCR efficiencies, the standard curves of several probes including msar, mcp, and msa were constructed using dd-PCR. The dd-PCR showed a slope value of 1.00 ± 0.03 (R2 = 0.99 ± 0.01), equivalent to 100% efficiency, over at least 4 orders of magnitude. Both technologies exhibited very similar levels of efficiency and linearity, with the same lower limits of detection. Quantification results were expressed as copy number microliter-DNA extract−1 for direct comparison. Each group was quantified from the three digesters using both technologies (Fig 1). mrtA, mcr-2b and Fen were not detected by either technology. dd-PCR detected seven groups from the digesters, while qPCR detected five groups.

ASTA-treatment partially reduced (23%) the H2O2 production observed in FA group as compared with PMA-control group (Fig. 3C). There was

an increase Bleomycin molecular weight of 97% in NO production after treatment with 0.3 mM of FA as compared with control group without LPS. Treatment of cells with ASTA in the FA group did not prevent the increase caused by the presence of FA. ASTA per se, raises nitric oxide production by 99% as compared with control group without LPS ( Fig. 3D). N-acetylcysteine (NAC) and BSA partially reduced the NO production induced by the FA mixture. To determine whether the increased levels of ROS induced by the FA mixture can modulate antioxidant status of cells, we evaluated the antioxidant enzyme activities after 24 h of treatment (Table 1). The FA mixture decreased the activity of CAT by 42% and increased the total-SOD activity by 27% as compared to the control group. The FA group with ASTA restored total-SOD activity to those of the control group, whereas CAT activity decreased by 71% and GR activity increased by 80% as compared with the control group. Among all front line antioxidant enzymes tested, total-SOD was increased by 52% and GR HDAC inhibitor activity was decreased by 28% due to ASTA treatment. Oxidative damages in biomolecules were also

modulated by the FA mixture. TBARS levels were dramatically increased by treatment of cells with a FA mixture (210%) and ASTA-treatment partially restored TBARS levels (112%) as compared with the control cells. Free protein SH-group was decreased in 69% in cells treated with FA. After treatment with 2 μM of ASTA a partial restoring of 41% was observed in thiol content groups. Carbonyl groups were not modulated by the treatment of cells with FA and ASTA (data not shown). A significant reduction in the content of GSH and GSSG of 73% and 35%, respectively was observed in lymphocytes treated with 0.3 mM

of the FA mixture when compared to the control DNA ligase group. This reduction was not prevented by ASTA addition (Fig 4). It has been postulated that FA may influence cells of the immune system, including lymphocytes by modifying cell-membrane composition (Fan et al., 2004 and Li et al., 2006), altering intracellular signaling pathways (Gorjao et al., 2007, Lee et al., 2004, Madani et al., 2001 and Mizota et al., 2009), proliferation capacity, interleukins release (Nunes et al., 2008, Sacerdote et al., 2005 and Verlengia et al., 2004), ROS production (Cury-Boaventura and Curi, 2005 and Stentz and Kitabchi, 2006; Otton et al., 2007), gene expression (Verlengia et al., 2004) and calcium mobilization (Otton et al., 2007). Overall, the mixture of FA used in the present study caused a marked increase in the production of superoxide anion, hydrogen peroxide and nitric oxide, which was accompanied by an increase in total-SOD activity and in levels of TBARS as well as a reduction of catalase, levels of free thiol groups and GSH content.

Analyses of neural activities at the end of the secondary task showed another important facet of interference effects find more in the LPFC. Watanabe and Funahashi [33••] found a significant ‘reawakening’ of neural encoding for

the visual cue location in the memory task after the end of the attention task (Figure 3e), which indicates that even under the presence of the interference effect caused by the attention task, some neural mechanisms in the LPFC could operate to compensate for the interference effect produced by the attention task. Similar results have been reported by Miyazaki et al. [32], who compared the activities of LPFC neurons and dorsal premotor neurons while monkeys performed a dual task, which consisted of memory-guided bimanual actions (primary task) and visually-guided bimanual actions (secondary task). The observed post-interference reactivation of the primary-task information showed that the LPFC played an important

role in exerting compensatory control over the interference by the secondary task. Flexible prioritization among multiple streams of concurrent task processing is critical for the coordination of dual-task performance. The observed reactivation may correspond to the neural implementation of adaptive task coordination Ribociclib nmr in the LPFC 22 and 24. Behavioral analyses and physiological investigations of dual-task interference using monkeys are beginning to provide evidence regarding the neural mechanisms for interference control. The similarity of the behavioral patterns caused by dual-task interference in humans and monkeys and the capability Idoxuridine to elucidate the fine details of neural computations by neurophysiological methods support the view that the primate model

is an appropriate method for understanding the details of the neural mechanisms of the interference control and the flexible allocation of cognitive recourse. Nothing declared. Papers of particular interest, published within the period of review, have been highlighted as: • of special interest This work was supported in part by Grant-in-Aids for Scientific Research (Nos. 21240024 and 25240021) from the Japanese Ministry of Education, Culture, Sports, Science and Technology (MEXT) to SF and by Research Fellowships for Young Scientists from the Japan Society for the Promotion of Science to KW. “
“Current Opinion in Behavioral Sciences 2015, 1:17–22 This review comes from a themed issue on Cognitive neuroscience Edited by Cindy Lustig and Howard Eichenbaum http://dx.doi.org/10.1016/j.cobeha.2014.07.006 2352-1546/© 2014 Elsevier Ltd. All right reserved. One of the most prominent aspects of cognitive control has been characterized as ‘inhibition’ or inhibitory processing.

As recomendações atuais das sociedades científicas europeia (EASL) e americana (AASLD) diferem, no que respeita à pesquisa de infecção concomitante pelo vírus delta nos doentes com infecção crónica pelo VHB: a sociedade americana considera que, na avaliação

inicial destes doentes, se deve excluir co-infecção selleck kinase inhibitor VHD apenas naqueles oriundos de áreas hiperendémicas e/ou com história de utilização de drogas endovenosas7; a sociedade europeia aconselha a pesquisa sistemática da co-infecção pelo VHD em todos os doentes8. Assim, tendo em conta as recomendações internacionais, o diagnóstico do doente apresentado foi tardio, não só porque se tratava de um doente oriundo de uma área hiperendémica, como pelo típico padrão

evolutivo laboratorial e histológico, mostrando persistência de baixa replicação do VHB (< 2000 UI/mL)7, mas com atividade inflamatória marcada, evidenciada pelo progressivo aumento das aminotransferases e pelos achados da biopsia hepática. Pelo diagnóstico ter sido tardio, não foi possível distinguir superinfecção de co-infecção, uma vez que não se identificou o momento exato da aquisição da infecção VHD. De igual modo, também não é possível estabelecer a duração da infecção pelo VHB, sendo possíveis transmissões de tipo vertical, perinatal ou sexual. Os valores prévios de aminotransférases, dos Ac anti-VHD e do AcHBc IgM seriam fundamentais para aquela CH5424802 classificação. O Ac anti-VHD IgM pode estar presente tanto na co-infecção como na superinfecção pelo que não é útil para diferenciar as duas situações. A distinção depende da duração da infecção pelo HBV, se crónica ou aguda, pelo que a característica distintiva sorológica da co-infecção é a presença de anti-HBc 5-Fluoracil IgM no soro1. Sabendo que apenas 2% dos doentes com co-infecção e que > 90% dos casos de superinfecção evoluem para cronicidade2, podemos afirmar que é maior a probabilidade de se tratar de uma situação de superinfecção. Também, a constatação da existência de um estádio de doença pouco avançado − fibrose moderada − permite especular a favor de uma recente superinfecção pelo VHD.

O método de diagnóstico, baseado na pesquisa de Ac VHD, foi suficiente para o diagnóstico de infecção ativa pelo VHD, dado estar presente a fração IgM do Ac VHD. A determinação do ARN-VHD não foi, naquela altura, possível. Este é o método mais específico e sensível para o diagnóstico da infecção, devendo ser considerado nos doentes com Ig G anti-VHD positiva, permitindo confirmar a presença de infecção ativa. A carga viral VHD tem também um papel importante durante o tratamento permitindo monitorizar a resposta à terapêutica2 and 4. A infecção concomitante com outros vírus, nomeadamente VHB, VHC e VIH (que partilham as mesmos vias de transmissão), está associada a diversos processos de inibição da replicação viral recíproca.

Much of the mechanism of X chromosome inactivation has been this website extensively studied and well characterized, including understanding the role of the antisense inhibitor, Tsix, to the proteins recruited to maintain the chromosome-wide inactivation, and the DNA–RNA–protein interactions that maintain X inactivation [ 4, 5, 6, 7 and 8]. However, a recent breakthrough was made in understanding how Xist is able to spread along the length of the entire chromosome without silencing other chromosomes or active areas of the X chromosome. Engreitz et al. using

1054 tiled probes to the 17-kb Xist transcript, pulled down unique sequences of genomic DNA bound to Xist at five time points during differentiation as Xist becomes induced. After ruling out the role of sequence motifs with Xist-recruiting ability, they found that the initial DNA sites bound by Xist were spatially proximal (based on Hi-C data) to the Xist locus [ 9••]. These results support a model that Xist spreads along the length of the chromosome by binding to distal sites that are spatially organized close to the newly transcribed Xist RNA. Osimertinib order By being able to modify chromatin structure at these regions, Xist is able to spread to newly silenced regions of the genome. Furthermore, regions that escape XCI are able to loop out and remain active while still permitting spatial spread of Xist. Since much more of the genome escapes XCI in humans

compared to mouse, it will be interesting to determine if this mechanism is conserved in humans. Other work has identified a new long non-coding RNA, XACT, specifically in human pluripotent stem cells [ 10••]. While not expressed in mice, XACT coats the active X chromosome and, in the absence of XIST, coats both chromosomes. Perhaps this reflects a human-specific mechanism by which cells prevent silencing of both X

chromosome, instead of, as in mouse, using TSIX as an antisense repressor. It is known that the human TSIX RNA has significantly less complementarity to human XIST than mouse Tsix and Xist, and its ability to act as an effective suppressor in this way has been questioned [ 11 and 12]. GABA Receptor This paper begins to shed light on human specific aspects of XCI that may underlie the mechanistic differences between mouse and human. Finally, two other studies provide additional pieces of the mechanistic puzzle. First is evidence for the role of Jarid2 in recruiting PRC2 to Xist RNA in helping to mediate inactivation [ 13•]. The second is the surprising finding that the first intron of Xist seems dispensable for Xist expression and normal function during XCI in stem cells and during development, despite the fact that the region exhibits strong pluripotency factor binding [ 14•]. Taken together these mechanistic results illustrate that there is still much to learn about XCI in both humans and mice. The role of the X chromosome in cancer has been well documented but much data is only correlational [15, 16, 17 and 18].