IVIVC approach based on carbamazepine bioequivalence studies combination.

The aim of the present study was to explore the feasibility of obtaining an IVIVC by combination of data from two bioequivalence (BE) studies of carbamazepine (CBZ) in order to assess if the previously published dissolution media and conditions could be applicable to any other oral immediate release (IR) CBZ products with conventional excipients. Twenty-four healthy male subjects from two BE study received one IR dose of the test (test 1 or 2) or the reference formulation (Tegretol, 400 mg). Dissolution studies of the IR CBZ tablets were performed in two different laboratories. In order to develop IVIVC, individual or average data analysis were considered. A level C, level B and level A correlation have been successfully developed by combining data from different BE studies of CBZ immediate release drug products. A level A IVIVC was developed with all four datasets with a good R2 for all the combinations of in vivo and in vitro data. A dissolution medium containing 1% SLS has demonstrated its suitability as the universal biopredictive dissolution medium, even if different batches and in vivo/in vitro studies were combined.

Atención farmacéutica a pacientes en tratamiento con AINE / Pharmaceutical care to patients under treatment with NSAIDs

Introducción: La automedicación es, en general, una conducta presente en todas las sociedades, y con frecuencia se autoprescriben antiinflamatorios sin control sanitario y sin que el paciente sea consciente de la intensidad y gravedad de las reacciones adversas que pueden provocar. Desde la oficina de farmacia se debe realizar una correcta atención farmacéutica y mejorar los resultados de la farmacoterapia previniendo, detectando y resolviendo los problemas relacionados con medicamentos antes de que éstos den lugar a morbilidad y mortalidad. Objetivos: 1) Analizar los principios activos más demandados, así como la forma de dispensación más frecuente. 2) Valorar la eficacia y la eficiencia de los medicamentos en las enfermedades para las que se prescriben. 3) Evaluar el grado de conocimiento de los pacientes sobre su farmacoterapia. 4) Realizar un análisis del seguimiento farmacoterapéutico a pacientes crónicos. Material y métodos: Estudio observacional, prospectivo, monocéntrico y concurrente llevado a cabo en pacientes tratados con antiinflamatorios, mediante encuestas y seguimiento farmacoterapéutico de los pacientes crónicos. Resultados: Los pacientes refirieron una disminución en el grado de dolor de 4 puntos según la escala visual analógica (EVA). Se redujo un 23,3% el número de pacientes con presión arterial sistólica (PAS) >=140 mmHg, y un 13,3% los pacientes con presión arterial diastólica (PAD) >=90 mmHg. Más del 90% declararon conocer mejor su enfermedad y su tratamiento, y el 58% mejoraron su adherencia a éste. La calidad de vida del paciente se vio aumentada en casi un 10% según el test EuroQol-5D. Conclusiones: La atención farmacéutica se presenta como una alternativa de calidad muy eficaz para conseguir mejorar el resultado de los tratamientos y la asistencia sanitaria(AU)

Introduction: Self-medication is generally present in all societies. Nonsteroidal anti-infl ammatory medications are one of the most commonly self-administered drugs and many patients without being aware of their side effects that can cause. From the pharmacy must make a proper pharmaceutical care and improve outcomes of drug therapy in preventing, detecting and solving drug therapy problems before they result in morbidity and mortality. Objectives: 1) To analyze the most demanded active principle and the most common form of dispensation. 2) To assess the effectiveness and efficiency of drugs for diseases those are prescribed. 3) To analyze the level of awareness of patients regards their drug thera py. 4) To assess the impact of pharmaceutical care to chronic patients. Methodology: The method used was a single-center prospective observational study in patients receiving anti-infl ammatory by questionnaires drafted and pharmaceutical intervention at pharmaceutical care for chronic patients. Results: The patients reported a reduction of 4 points in degree of pain according to the visual analog scale (VAS). The number of patients with systolic blood pressure (SBP) >=140 mmHg, and the number of patients with diastolic blood pressure (DBP) >=90 mmHg, was reduced 23.3 and 13.3%, respectively. Over 90% reported understand better their disease and treatment, 58% improved adherence. The patient’s quality of life was increased by almost 10% according to the test EuroQol-5D. Conclusions: Pharmaceutical care is presented as a very effective quality alternative to achieve better treatment outcomes and healthcare(AU)

Distribution of HOX genes in the chicken genome reveals a new segment of conservation between human and chicken.

Homeobox genes play an important role in the regulation of early embryonic development. They represent a family of evolutionarily highly conserved transcription factors. In this work, several genes that belong to the four HOX gene clusters are assigned by in situ hybridization to four distinct chicken chromosomes. The four gene clusters are mapped to 2p2.1 (HOXA), 3q3.1 (HOXB), 1q3.1 (HOXC) and 7q1.3--> q1.4 (HOXD). We confirm partial homologies already detected by genetic mapping between chicken chromosomes 1, 2 and 7 and human chromosomes 12, 7 and 2 and we describe a new conserved segment between chicken chromosome 3 and human chromosome 17. These results represent the first data that confirm the physical linkage between chicken HOX genes and may improve our understanding of phylogenetic relationships and genome evolution.

Misexpression of Fgf-4 in the chick limb inhibits myogenesis by down-regulating Frek expression.

Skeletal muscle development involves an initial period of myoblast replication followed by a phase in which some myoblasts continue to proliferate while others undergo terminal differentiation. The latter process involves the permanent cessation of DNA synthesis, activation of muscle-specific gene expression, and fusion of single cells to generate multinucleated muscle fibres. The in vivo signals regulating the progression through all these steps remain unknown. Fibroblast growth factors (Fgfs) and Fgf receptors comprise a large family whose members have been shown to play multiple roles in the development of skeletal muscle in vitro. Exogenously applied Fgfs are able to stimulate proliferation and suppress myogenic differentiation in cell culture. We sought to determine the role played by Fgf-4 during limb myogenesis in vivo. Fgf-4 transcripts are located at both extremities of myotubes whereas the mRNAs of one of the Fgf receptors, Frek, are detected in mononucleated proliferating myoblasts surrounding the multinucleated fibres. Overexpression of mouse Fgf-4 (mFgf-4) using a replication-competent retrovirus, RCAS, leads to a down-regulation of muscle markers followed by an inhibition of terminal differentiation in limb muscles. Using quail/chick transplantations we were able to follow the muscle cells and found a dramatic decrease in their number after exposure to mFgf-4. Interestingly ectopic mFgf-4 down-regulates Frek transcripts in limb muscle areas. We conclude that overexpression of mFgf-4 inhibits myoblast proliferation, probably by down-regulating Frek mRNAs. This suggests a role for Fgf-4, located at the extremities of the myotubes, where it could be responsible for the absence of Frek mRNA in the muscle fibre.

Expression of Frzb-1 during chick development.

We cloned the chick homolog of Xenopus and mouse Frzb-1, a secreted Wnt antagonist and performed in situ hybridizations to determine the pattern of cFrzb-1 expression in the developing chick embryo. At early stages, cFrzb-1 transcripts are located exclusively in the ectodermal layer corresponding to the neural plate. The labelling continues in the neural tube, but is always excluded from the floor plate. cFrzb-1 mRNA is expressed by migrating cephalic and truncal neural crest cells. Later, cFrzb-1 transcripts are found in a subset of neural crest derivatives such as cephalic cartilage, nerves and spinal ganglia. In addition to ectodermal derivatives, cFrzb-1 transcripts were also observed in mesodermal derivatives such as vertebral and limb cartilage, the adrenal cortex, the gonads, and a subpopulation of blood cells.

Patterning signals acting in the spinal cord override the organizing activity of the isthmus.

The regionalization of the neural tube along the anteroposterior axis is established through the action of patterning signals from the endomesoderm including the organizer. These signals set up a pre-pattern which is subsequently refined through local patterning events. The midbrain-hindbrain junction, or isthmus, is endowed with such an organizing activity. It is able to induce graded expression of the Engrailed protein in the adjacent mesencephalon and rhombencephalon, and subsequently elicits the development of tectal and cerebellar structures. Ectopically grafted isthmus was also shown to induce Engrailed expression in diencephalon and otic and pre-otic rhombencephalon. Fgf8 is a signalling protein which is produced by the isthmus and which is able to mimic most isthmic properties. We show here that the isthmus, when transposed to the level of either rhombomere 8 or the spinal cord, loses its ability to induce Engrailed and cerebellar development in adjacent tissues. This is accompanied by the down-regulation of fgf8 expression in the grafted isthmus and by the up-regulation of a marker of the recipient site, Hoxb-4. Moreover, these changes in gene activity in the transplant are followed by a transformation of the fate of the grafted cells which adjust to their novel environment. These results show that the fate of the isthmus is not determined at 10-somite stage and that the molecular loop of isthmic maintenance can be disrupted by exogenous signals.

The avian fli gene is specifically expressed during embryogenesis in a subset of neural crest cells giving rise to mesenchyme.

The ets-family of transcription factors is involved in the development of endothelial and hematopoietic cells. Among these genes, fliwas shown to be responsible for erythroblastomas and Ewing's sarcomas. Its involvement in Ewing's sarcoma, a putative neurectodermal tumor, as well as the in situ hybridization studies performed in mice and Xenopus suggested a role in neural crest development. We cloned quail fli cDNA in order to analyze in more detail its expression in neural crest cells, which have been extensively studied in avian species. Fli gene maps on chicken chromosome 1 to band q31->q33. Two RNAs are transcribed, most likely arising from two different promoters. The analysis of its expression in neural crest cells reveals that it is expressed rather late, when the neural crest cells reach their target. Among the various lineages derived from the crest, it is restricted to the mesenchymal one. It is maintained at later stages in the cartilage of neural crest but also of mesodermal origin. In addition, fli is expressed in several mesoderm-derived cells: endothelial cells as well as intermediate and splanchnopleural mesoderm.

Defined concentrations of a posteriorizing signal are critical for MafB/Kreisler segmental expression in the hindbrain.

It has been shown by using the quail/chick chimera system that Hox gene expression in the hindbrain is influenced by positional signals arising from the environment. In order to decipher the pathway that leads to Hox gene induction, we have investigated whether a Hox gene regulator, the leucine zipper transcription factor MafB/Kr, is itself transcriptionally regulated by the environmental signals. This gene is normally expressed in rhombomeres (r) 5 and 6 and their associated neural crest. MafB/Kr expression is maintained in r5/6 when grafted into the environment of r3/4. On the contrary, the environment of rhombomeres 7/8 represses MafB/Kr expression. Thus, as previously shown for the expression of Hox genes, MafB/Kr expression is regulated by a posterior-dominant signal, which in this case induces the loss of expression of this gene. We also show that the posterior signal can be transferred to the r5/6 neuroepithelium by posterior somites (somites 7 to 10) grafted laterally to r5/6. At the r4 level, the same somites induce MafB/Kr in r4, leading it to behave like r5/6. The posterior environment regulates MafB/Kr expression in the neural crest as it does in the corresponding hindbrain level, showing that some positional regulatory mechanisms are shared by neural tube and neural crest cells. Retinoic acid beads mimic the effect produced by the somites in repressing MafB/Kr in r5/6 and progressively inducing it more rostrally as its concentration increases. We therefore propose that the MafB/Kr expression domain is defined by a molecule unevenly distributed in the paraxial mesoderm. This molecule would allow the expression of the MafB/Kr gene in a narrow window of concentration by activating its expression at a definite threshold and repressing it at higher levels, accounting for its limited domain of expression in only two rhombomeres. It thus appears that the regulation of MafB/Kr expression in the rhombomeres could be controlled by the same posteriorizing factor(s) as Hox genes.

Hox gene induction in the neural tube depends on three parameters: competence, signal supply and paralogue group.

It has been previously shown that Hox gene expression in the rhombencephalon is controlled by environmental cues. Thus posterior transposition of anterior rhombomeres to the r7/8 level results in the activation of Hox genes of the four first paralog groups and in homeotic transformations of the neuroepithelial fate according to its position along the anteroposterior axis. We demonstrate here that although the anteroposterior levels of r2 to r6 express Hox genes they do not have inducing activity on more anterior territories. If transposed at the posterior rhombencephalon and trunk level, however, the same anterior regions are able to express Hox gene such as Hoxa-2, a-3 or b-4. We also provide evidence that these signals are transferred by two paths: one vertical, arising from the paraxial mesoderm, and one planar, travelling in the neural epithelium. The competence to express Hox genes extends up to the forebrain and midbrain but expression of Hox genes does not preclude Otx2 expression in these territories and results only in slight changes in their phenotypes. Similarly, rhombomeres transplanted to posterior truncal levels turned out to be able to express posterior genes of the first eight paralog groups to the exclusion of others located downstream in the Hox genes genomic clusters. This suggests that the neural tube is divided into large territories characterized by different Hox gene regulatory features.

Plasticity of transposed rhombomeres: Hox gene induction is correlated with phenotypic modifications.

In this study we have analysed the expression of Hoxb-4, Hoxb-1, Hoxa-3, Hoxb-3, Hoxa-4 and Hoxd-4 in the neural tube of chick and quail embryos after rhombomere (r) heterotopic transplantations within the rhombencephalic area. Grafting experiments were carried out at the 5-somite stage, i.e. before rhombomere boundaries are visible. They were preceeded by the establishment of the precise fate map of the rhombencephalon in order to determine the presumptive territory corresponding to each rhombomere. When a rhombomere is transplanted from a caudal to a more rostral position it expresses the same set of Hox genes as in situ. By contrast in many cases, if rhombomeres are transplanted from rostral to caudal their Hox gene expression pattern is modified. They express genes normally activated at the new location of the explant, as evidenced by unilateral grafting. This induction occurs whether transplantation is carried out before or after rhombomere boundary formation. Moreover, the fate of the cells of caudally transplanted rhombomeres is modified: the rhombencephalic nuclei in the graft develop according to the new location as shown for an r5/6 to r8 transplantation. Transplantation of 5 consecutive rhombomeres (i.e. r2 to r6), to the r8 level leads to the induction of Hoxb-4 in the two posteriormost rhombomeres but not in r2,3,4. Transplantations to more caudal regions (posterior to somite 3) result in some cases in the induction of Hoxb-4 in the whole transplant. Neither the mesoderm lateral to the graft nor the notochord is responsible for the induction. Thus, the inductive signal emanates from the neural tube itself, suggesting that planar signalling and predominance of posterior properties are involved in the patterning of the neural primordium.