Map location of ace-5.

Map location of ace-5

Characterization of a continuous phase transition in a chaotic system

We discuss a scaling invariance for chaotic diffusion in a transition from integrabilityto nonintegrability in a class of dynamical systems described by a two-dimensional, nonlinear,and area-preserving mapping. The variables describing the system are the action I and the angle θ, which have the property of diverging in the limit of vanishingly action. The phase transition is controlled by a parameter ϵ. A scaling invariance observed for the average squared action along the chaotic sea proves that the transition observed from integrability to nonintegrability is equivalent to a second order and is therefore called a continuous phase transition. A clear signature of this is to the fact that the order parameter approaches zero simultaneously, and the response of the order parameter to the variation of the control parameter (susceptibility) diverges. Discutimos uma invariância de escala para a difusão caótica em uma transição de fase de integrabilidade para não integrabilidade em uma classe de  sistemas dinâmicos descritos por um mapeamento bidimensional, não linear e preserva a área no espaço de configurações. As variáveis que descrevem o sistema são a ação I e o ângulo θ. Este tem a propriedade de divergir no limite em que a ação é suficientemente pequena. A transição de fase é controlada por um parâmetro ϵ. Uma invariância de escala observada para a ação quadrática média ao longo do mar caótico prova que a transição observada da integrabilidade para a não integrabilidade é equivalente a uma transição de fase de segunda ordem, que é também conhecida como transição de fase contínua. Uma evidência clara disso refere-se ao fato de que o parâmetro de ordem se aproxima de zero ao mesmo tempo que a susceptibilidade - resposta do parâmetro de ordem à variação do parâmetro de controle - diverge no mesmo limite.

A novel, lineage-primed prestalk cell subtype involved in the morphogenesis of D-discoideum

Dictyostelium morphogenesis requires the tip, which acts as an organizer and conducts orchestrated cell movement and cell differentiation. At the slug stage the tip region contains prestalk A (pstA) cells, which are usually recognized by their expression of reporter constructs that utilize a fragment of the promoter of the ecmA gene. Here, using the promoter region of the o-methyl transferase 12 gene (omt12) to drive reporter expression, we demonstrate the presence, also within the pstA region, of a novel prestalk cell subtype: the pstVA cells. Surprisingly, a sub-population of the vegetative cells express a pstVA: GFP marker and, sort out to the tip, both when developing alone and when co-developed with an excess of unmarked cells. The development of such a purified GFP-marked population is greatly accelerated: by precocious cell aggregation and tip formation with accompanying precocious elevation of developmental gene transcription. We therefore suggest that the tip contains at least two prestalk cell subtypes: the developmentally-specified pstA cells and the lineage-primed pstVA cells. It is presumably the pstVA cells that play the dominant role in morphogenesis during the earlier stages of development. The basis for the lineage priming is, however, unclear because we can find no correlation between pstVA differentiation and nutrient status during growth or cell cycle position at the time of starvation, the two known determinants of probable cell fate

Effect of splenectomy on type-1/type-2 cytokine gene expression in a patient with adult idiopathic thrombocytopenic purpura (ITP)

BACKGROUND: In view of clinical observations and laboratory results that support a central role of the spleen in idiopathic thrombocytopenic purpura (ITP) pathophysiology, we studied the effect of splenectomy on type-1 and type-2 cytokine gene expression in an adult ITP case, refractory to conservative treatment. CASE PRESENTATION: The patient was subjected to splenectomy 9 months after the diagnosis with complete response, attaining platelet counts over 150 × 10(6)/L within 10 days after the operation. Two consecutive blood samples were obtained from the patient, 3 and 7 months after the splenectomy for the purposes of this study. A control group consisted of 11 healthy adults. Peripheral blood mononuclear cells were prepared from each blood sample and cultured in vitro for 8 h with the addition of the mitogens phorbol myristate acetate and ionomycin. Total cellular RNA extracted from 10(6 )cells was submitted to semiquantitave reverse transcriptase-polymerase chain reaction (RT-PCR) for the amplification of IL-2, IFN-γ, IL-4, IL-5, and IL-10 metagraphs. The PCR products were run on ethidium-stained agarose gels, photographed and quantified by densitometry. A steep decrease of type-1 cytokine expression (IL-2, IFN-γ) and their calculated sum expressing Th1 activity was observed at 7 months post-splenectomy compared to 3 months post-splenectomy, in parallel with a rise of platelet count from 190 × 10(6)/L to 265 × 10(6)/L. The change of type-2 cytokine expression (IL-4, IL-5, IL-10) was slight and the Th2 activity (IL-4+IL-5) remained largely unchanged. The Th1/Th2 ratio, that reflects the pathogenic disease-specific T-cell immune deviation, was accordingly reduced 7 months post-splenectomy (Th1/Th2 = 1.3) compared to 3 months (Th1/Th2 = 3.5). CONCLUSIONS: The reduction of the Th1/Th2 cytokine ratio that was observed over time after splenectomy was accompanied by full clinical remission. Nevertheless, the persistence of a type-1 polarization, even after several months following spleen removal, is suggestive of a more basic abnormality of the immune function in these patients

Nintedanib in patients with systemic sclerosis-associated interstitial lung disease: subgroup analyses by autoantibody status and skin score

OBJECTIVE: We used data from the SENSCIS trial to assess the effects of nintedanib versus placebo in subgroups of patients with SSc-ILD based on characteristics associated with progression of SSc-ILD in previous studies. METHODS: Patients with SSc-ILD were randomized to receive nintedanib or placebo, stratified by anti-topoisomerase I antibody (ATA) status. We assessed the rate of decline in forced vital capacity (FVC) (mL/year) over 52 weeks in subgroups by baseline ATA status, modified Rodnan skin score (mRSS) ( 0.05 for all). CONCLUSION: In patients with SSc-ILD, no heterogeneity was detected in the treatment effect of nintedanib in reducing the annual rate of decline in FVC across subgroups based on ATA status, mRSS, and SSc subtype

Complications of Evans' syndrome in an infant with hereditary spherocytosis: a case report

Hereditary spherocytosis (HS) is a genetic disorder of the red blood cell membrane clinically characterized by anemia, jaundice and splenomegaly. Evans' syndrome is a clinical syndrome characterized by autoimmune hemolytic anemia (AIHA) accompanied by immune thrombocytopenic purpura (ITP). It results from a malfunction of the immune system that produces multiple autoantibodies targeting at least red blood cells and platelets. HS and Evans' syndrome have different mechanisms of pathophysiology one another. We reported the quite rare case of an infant who had these diseases concurrently. Possible explanations of the unexpected complication are discussed

Expression and function of the Delta-1/Notch-2/Hes-1 pathway during experimental acute kidney injury

The Notch signaling pathway consists of several receptors and their ligands Delta and Jagged and is important for embryogenesis, cellular differentiation and proliferation. Activation of Notch receptors causes their cleavage yielding cytoplastic domains that translocate into the nucleus to induce target proteins such as the basic-loop-helix proteins Hes and Hey. Here we sought to clarify the significance of the Notch signaling pathway in acute kidney injury using a rat ischemia-reperfusion injury model and cultured NRK-52E cells. Analysis of the whole kidney after injury showed increased expression of Delta-1 and Hes-1 mRNA and protein along with processed Notch-2. Confocal microscopy, using specific antibodies, showed that Delta-1, cleaved Notch-2 and Hes-1 colocalized in the same segments of the injured renal proximal tubules. Recombinant Delta-1 significantly stimulated NRK-52E cell proliferation. Our study suggests that the Delta-1/Notch-2/Hes-1 signaling pathway may regulate the regeneration and proliferation of renal tubules during acute kidney injury