IIR approximations to the fractional differentiator/integrator using Chebyshev polynomials theory

This paper deals with the use of Chebyshev polynomials theory to achieve accurate discrete-time approximations to the fractional-order differentiator/integrator in terms of IIR filters. These filters are obtained using the Chebyshev-Padé and the Rational Chebyshev approximations, two highly accurate numerical methods that can be computed with ease using available software. They are compared against other highly accurate approximations proposed in the literature. It is also shown how the frequency response of the fractional-order integrator approximations can be easily improved at low frequencies.

Latin American women's experiences with medical abortion in settings where abortion is legally restricted

Abortion is legally restricted in most of Latin America where 95% of the 4.4 million abortions performed annually are unsafe. Medical abortion (MA) refers to the use of a drug or a combination of drugs to terminate pregnancy. Mifepristone followed by misoprostol is the most effective and recommended regime. In settings where mifepristone is not available, misoprostol alone is used.Medical abortion has radically changed abortion practices worldwide, and particularly in legally restricted contexts. In Latin America women have been using misoprostol for self-induced home abortions for over two decades.This article summarizes the findings of a literature review on women's experiences with medical abortion in Latin American countries where voluntary abortion is illegal.Women's personal experiences with medical abortion are diverse and vary according to context, age, reproductive history, social and educational level, knowledge about medical abortion, and the physical, emotional, and social circumstances linked to the pregnancy. But most importantly, experiences are determined by whether or not women have the chance to access: 1) a medically supervised abortion in a clandestine clinic or 2) complete and accurate information on medical abortion. Other key factors are access to economic resources and emotional support.Women value the safety and effectiveness of MA as well as the privacy that it allows and the possibility of having their partner, a friend or a person of their choice nearby during the process. Women perceive MA as less painful, easier, safer, more practical, less expensive, more natural and less traumatic than other abortion methods. The fact that it is self-induced and that it avoids surgery are also pointed out as advantages. Main disadvantages identified by women are that MA is painful and takes time to complete. Other negatively evaluated aspects have to do with side effects, prolonged bleeding, the possibility that it might not be effective, and the fact that some women eventually need to seek medical care at a hospital where they might be sanctioned for having an abortion and even reported to the police.

Increased apoptosis is linked to severe acute GVHD in patients with Fanconi anemia

Fanconi anemia (FA) patients have an increased risk of acute GVHD (aGVHD) after hematopoietic SCT, with hypersensitivity to DNA-cross-linking agents and defective DNA repair. MicroRNA-34 and p53 can induce apoptosis after DNA damage.Here we assessed epithelial cell apoptosis, and studied TP53 and miR-34a expression in the skin and gut biopsies in five non-transplanted FA patients, in 20 FA patients with aGVHD and in 25 acquired aplastic anemia patients (AA). Epithelial apoptosis was higher in FA than in acquired AA patients in both the skin and gut biopsies, though they had a similar preparative regimen. Further study on gut biopsies in FA patients showed that this deleterious effect was not linked to TP53 gene overexpression. As, among p53-independent signaling pathways of apoptosis, the microRNA-34 family mimics p53 apoptotic effects in response to DNA damage, we studied miR-34a expression in the same series of FA patients' gut biopsies. MiR-34a expression level was higher in severe aGVHD compared with non-aGVHD subjects or non-transplanted patients, and significantly related to apoptotic cell numbers across the three groups of FA patients. Thus, in FA patients, increased apoptosis occurs in target epithelial cells of severe aGVHD, and this deleterious effect is linked to overexpression of miR-34a but not TP53.

Impact of early access to a palliative/supportive care intervention on pain management in patients with cancer

BACKGROUND

No study has so far addressed whether differences do exist in the management of cancer pain between patients receiving usual care by primary specialists and those receiving early palliative/supportive intervention.

PATIENTS AND METHODS

A multicentre cross-sectional study in 32 Italian Hospitals has included 1450 patients, receiving analgesic therapy for cancer pain: 602 with access to primary specialist alone (standard care, SC) and 848 with early access to a palliative/supportive care (ePSC) team, concomitant with primary oncology care.

RESULTS

Statistically significant differences in the analgesic drug administration according to care model have been evident: non-opioids were more frequently used in SC (9.5% versus 2%; P<0.001), while strong opioids in ePSC group (80% versus 63%; P<0.001). The number of patients with severe pain was lower in ePSC compared with SC group (31% versus 17%; P<0.001). Results of multivariate analysis have shown that ePSC integrated with primary oncologic care (relative risk 0.69; 95% confidence interval 0.48-0.99; P=0.045) was an independent factor associated with a 31% reduced risk of suffering from severe pain.

CONCLUSIONS

An ePSC team provides the most effective standard of analgesic therapy for cancer pain. A randomized clinical trial is needed to confirm these findings.

Renal actions of atrial natriuretic peptide in spontaneously hypertensive rats: the role of nitric oxide as a key mediator

Atrial natriuretic peptide (ANP) is an important regulator of blood pressure (BP). One of the mechanisms whereby ANP impacts BP is by stimulation of nitric oxide (NO) production in different tissues involved in BP control. We hypothesized that ANP-stimulated NO is impaired in the kidneys of spontaneously hypertensive rats (SHR) and this contributes to the development and/or maintenance of high levels of BP. We investigated the effects of ANP on the NO system in SHR, studying the changes in renal nitric oxide synthase (NOS) activity and expression in response to peptide infusion, the signaling pathways implicated in the signaling cascade that activates NOS, and identifying the natriuretic peptide receptors (NPR), guanylyl cyclase receptors (NPR-A and NPR-B) and/or NPR-C, and NOS isoforms involved. In vivo, SHR and Wistar-Kyoto rats (WKY) were infused with saline (0.05 ml/min) or ANP (0.2 μg·kg−1·min−1). NOS activity and endothelial (eNOS), neuronal (nNOS), and inducible (iNOS) NOS expression were measured in the renal cortex and medulla. In vitro, ANP-induced renal NOS activity was determined in the presence of iNOS and nNOS inhibitors, NPR-A/B blockers, guanine nucleotide-regulatory (Gi) protein, and calmodulin inhibitors. Renal NOS activity was higher in SHR than in WKY. ANP increased NOS activity, but activation was lower in SHR than in WKY. ANP had no effect on expression of NOS isoforms. ANP-induced NOS activity was not modified by iNOS and nNOS inhibitors. NPR-A/B blockade blunted NOS stimulation via ANP in kidney. The renal NOS response to ANP was reduced by Gi protein and calmodulin inhibitors. We conclude that ANP interacts with NPR-C, activating Ca-calmodulin eNOS through Gi protein. NOS activation also involves NPR-A/B. The NOS response to ANP was diminished in kidneys of SHR. The impaired NO system response to ANP in SHR participates in the maintenance of high blood pressure.

Malformación venosa en los músculos de la mano

En este artículo se detalla la presentación, tratamiento y evolución de una malformación venosa localizada en músculos intrínsecos de la mano derecha en una paciente, iniciándose a los 11 años de edad. Durante su evolución de 25 años, ha requerido tres cirugías. El aspecto estético y la función de la mano afectada se conservan aceptablemente.

Quantum-mechanical interference in charge exchange between hydrogen and graphene-like surfaces

The neutral to negative charge fluctuation of a hydrogen atom in front of a graphene surface is calculated by using the Anderson model within an infinite intra atomic Coulomb repulsion approximation. We perform an ab initio calculation of the Anderson hybridization function that allows investigation of the effect of quantum-mechanical interference related to the Berry phase inherent to the graphene band structure. We find that consideration of the interaction of hydrogen on top of many C atoms leads to a marked asymmetry of the imaginary part of the hybridization function with respect to the Fermi level. Consequently, Fano factors larger than one and strongly dependent on the energy around the Fermi level are predicted. Moreover, the suppression of the hybridization for energies above the Fermi level can explain the unexpected large negative ion formation measured in the scattering of protons by graphite-like surfaces.