Nucleation and growth inhibition of biological minerals by cementum attachment protein-derived peptide (CAP-pi).

Biomineralization is a highly regulated process where proteins/peptides-crystal interactions contribute to the shaping, phasing and aggregation of minerals. We have identified and synthesized a cementum attachment protein-derived peptide (CAP-pi), which corresponds to amino acids 40-53 of the N-terminal CAP domain (MASSDEDGTNGGAS) and its phosphorylated variant (MASpSpDEDGTNGGASp) (CAP-pip). The peptide is composed of polar and negatively charged amino acids, which are disordered, according to in silico analysis. Our results show that CAP-pi inhibits hydroxyapatite (HA) formation and growth. However, it possesses low capacity to inhibit calcium oxalate crystal growth. CAP-pip showed a stronger inhibitory effect on the formation and growth of HA. As well as a high capacity to inhibit calcium oxalate monohydrate growth, mainly due to adsorption on specific growth faces. Small peptides have many advantages over the full-size protein, including low-cost production and modulation characteristics that allow for structural changes. Our findings suggest that CAP-pip-derived peptide could possess therapeutic potential to prevent or treat pathological calcifications such as renal stones and vascular calcification.

Cementum protein 1-derived peptide (CEMP 1-p1) modulates hydroxyapatite crystal formation in vitro.

A cementum protein 1-derived peptide (CEMP1-p1) consisting of 20 amino acids from the CEMP1's N-terminus region: MGTSSTDSQQAGHRRCSTSN, and its role on the mineralization process in a cell-free system, was characterized. CEMP1-p1's physicochemical properties, crystal formation, and hydroxyapatite (HA) nucleation assays were performed. Crystals induced by CEMP1-p1 were analyzed by scanning electron microscopy, Fourier-transform infrared spectroscopy-attenuated total reflectance (FTIR-ATR), X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), and atomic force microscopy. The results indicate that CEMP1-p1 lacks secondary structure, forms nanospheres that organize into three-dimensional structures, possesses affinity to HA, and induces its nucleation. CEMP1-p1 promotes the formation of spherical structures composed by densely packed prism-like crystals, which revealed a Ca/P ratio of 1.56, corresponding to HA. FTIR-ATR showed predominant spectrum peaks that correspond and are characteristic of HA and octacalcium phosphate (OCP). Analysis by XRD indicates that the crystals show planes with a preferential crystalline orientation for HA and for OCP. HRTEM showed interplanar distances that correspond to crystalline planes of HA and OCP. Crystals are composed by superimposed lamellae, which exhibit epitaxial growth, and each layer of the crystals is structured by nanocrystals. This study reveals that CEMP1-p1 regulates HA crystal formation, somehow mimicking the in vivo process of mineralized tissues bioformation.

Synthetic cementum protein 1-derived peptide regulates mineralization in vitro and promotes bone regeneration in vivo.

The use of recombinant proteins has revolutionized the development of biologic pharmaceuticals; however, they are not free of complications. Some have very high molecular weight, some demonstrate in vivo instability, and the high cost of producing them remains a major problem. On the other hand, it has been shown that peptides derived from active domains keep their biologic activity and can trigger events, such as osteogenesis and bone regeneration. Small peptides are advantageous because of their ease of synthesis and handling and their low immunogenic activity. The purpose of this study was to investigate the functions of a synthetic peptide, cementum protein 1-peptide1 (CEMP-1-p1), both in vitro and in vivo. Our results show that CEMP-1-p1 significantly enhanced the proliferation and differentiation of human periodontal ligament cells toward a mineralizing-like phenotype, as evidenced by increasing alkaline phosphatase (ALP)-specific activity and osterix, runt-related transcription factor (RUNX)-2, integrin binding sialoprotein, bone morphogenetic protein-2, osteocalcin, and cementum protein (CEMP)-1 expression at mRNA and protein levels. In vivo assays performed through standardized critical-size calvarial defects in rats treated with CEMP-1-p1 resulted in newly formed bone after 30 and 60 d. These data demonstrate that CEMP-1-p1 is an effective bioactive peptide for bone tissue regeneration. The application of this bioactive peptide may lead to implementing new strategies for the regeneration of bone and other mineralized tissues.-Correa, R., Arenas, J., Montoya, G., Hoz, L., López, S., Salgado, F., Arroyo, R., Salmeron, N., Romo, E., Zeichner-David, M., Arzate, H. Synthetic cementum protein 1-derived peptide regulates mineralization in vitro and promotes bone regeneration in vivo.

[Critical reading of reports of educational research in teachers of IMSS. Multicenter study]. / Lectura crítica de informes de investigación educativa en profesores del IMSS. Estudio multicéntrico.

AIM: To determine the effect of an educational strategy promoting participation in the development of critical reading of educational research reports on professors of Educational Research and Teacher Education (CIEFD's). MATERIAL AND METHODS: We performed an intervention study, multicenter professors (medical specialists) who enrolled in the courses: Diploma in teaching methodological level 1 and 2 (n = 46, n = 29, respectively) in the six CIEFD's (D.F. Siglo XXI, DF. La Raza, Nuevo León, Sonora, Puebla and Jalisco), in the period March to August 2007. A tool was built that assessed the variables critical appraisal of educational research reports, the construct validity, content and reliability was assessed by experts in education research. The educational strategy developed in the form of seminars, which were held three times a week in the Certification in teaching methodological level 1 and twice per week in the Certification Level 2 in teaching methodology duration per session: 6 h. The instrument was applied at the beginning and end of the course. RESULTS: In the two Graduates it was observed in the total group, an advance in the three indicators of critical reading, which was expressed with statistically significant differences; in the global score of the Diploma level 1 (final vs. initial measurement) the following mediums were observed: 36-67 (p = 0.0001); in the Diploma level 2, it was observed in its overall rating: 42-78 (p = 0.0001). DISCUSSION: This inquiry from the results observed some of theoretical approaches to mainstreaming participatory. CONCLUSION: An educational strategy promoting participation produced a breakthrough in the three indicators (to interpret, to judge and to formulate proposals) for critical reading of educational research reports.

[Participatory education and the development of critical reading in teachers theoretical texts. Multicenter study]. / Educación participativa y el desarrollo de la lectura crítica de textos teóricos en profesores. Estudio multicéntrico.

AIM: Determine what the relationship between participation in classroom of students attending courses at the Educational Research and Teacher Education (CIEFD's) and the development of proficiency in critical reading of theoretical texts in education. MATERIAL AND METHODS: Intervention study, multicenter students (medical specialist) level Diploma in teaching methodology (DMDN) 1 and 2 (n=46 n=29) of the six CIEFD's (DF Siglo XXI, Mexico City La Raza, Nuevo Leon, Sonora, Puebla and Veracruz), period: March to August 2007 and a Masters in education (n=9, generation 2007-2008). Two instruments were constructed that evaluated the participation variables and critical reading of theoretical texts in education, conceptual validity; content and reliability were assessed by experts in education research. The educational intervention was in the form of seminars (three times a week in DMDN 1 and twice weekly in DMDN 2 and Masters). Participation was assessed halfway through the course and on completion, critical reading at the beginning as well as the end. RESULTS: Statistically significant associations were observed in DMDN 1 (four Centers) and the Masters, but not DMDN 2. DISCUSSION: In this investigation some of the theoretical proposals of the participatory education were recreated, starting from the analysis of our results. CONCLUSION: In some centers and in the masters, strengthening participation in this educational intervention is related to the development of critical reading of theoretical texts in education.

[Clinical competence of anesthesiology residents in patients requiring hospital care in the specialty hospital "Siglo XXI"]. / Competencia clínica de los residentes de anestesiología en pacientes que requieren atención médica en un hospital de especialidades.

INTRODUCTION: The study of clinical competence is essential because it summarizes the attributes that characterize a specialist capable of providing quality health care OBJECTIVE: Investigate the development of clinical competence among anesthesiology residents that care for patients in a tertiary level facility. MATERIAL AND METHODS: In February 2007 we conducted a cross-sectional study among 42 anesthesiology residents, 21 were in second and 21 in third year. In order to measure the degree of development of clinical competence we created an instrument with four case studies that summarized patients undergoing surgical anesthetic procedure. The instrument included 200 items that explored eight indicators and covered a range of time periods: pre-trans and post anesthesia. The instrument was validated by a group of experts with clinical, teaching and publication experience. We carried out a pilot test and estimated the instrument's internal reliability using the Kuder-Richardson test (KR-21). We obtained a coefficient of 0.95. We collected the study data and instrument rating technique using a blinded design. Statistical analysis was performed using nonparametric tests. RESULTS: In the overall ranking, third-year medical residents versus sophomores, achieved the highest scores, which resulted in statistically significant differences (p = 0.045). Regarding the degree of expertise we found that most participants had scores of "very low" and "low". In the study of ratings by indicator, we noted that when comparing second vs third year residents we only found statistically significant differences in default decisions that were also potentially iatropathogenic (p = 0.026). CONCLUSION: The clinical competence of anesthesiology residents who care for patients attending a tertiary level facility is low when compared with the maximum theoretical scores they should obtain.

[Clinical competence of emergency clinicians in the management of asthmatic exacerbation in children]. / Competencia clínica de médicos de urgencias en la atención de niñios con exacerbación asmática.

UNLABELLED: In spite of its high prevalence, asthma continues to be undertreated worldwide, and a physician's deficient knowledge seems to be the main reason. OBJECTIVES: To measure the degree of physician's knowledge about classification and treatment of asthma exacerbations in children, and to identify physician's factors that might be involved. METHODS: A prospective, observational, cross-sectional and analytical study was carried out. A 13 item questionnaire to evaluate the knowledge about asthma exacerbations was constructed and validated. This instrument was applied to clinicians working at emergency rooms in four secondary-level hospitals. RESULTS: Forty doctors answered the questionnaire, with a median of 38.5% correct answers. Age, time-span working as specialist, years working at emergency rooms, number of courses attended, number of papers on asthma read, and number of asthma patients seen in a weekly basis did not influence the percentage of correct answers. Variables influencing the degree of knowledge were: being pediatrician (38.5% correct answers vs 23.1% in other specialties, p = 0.035) and working at night (50.0 vs 30.8% in other shift p = 0.031). A multiple lineal regression analysis corroborated the influence of these last two variables on the percentage of correct answers. CONCLUSIONS: The questionnaire proved to be a useful tool that fulfilled expected goals. Percentage of correct answers was low among participating physicians, which indicated the need of educative intervention maneuvers to improve medical management of asthma exacerbation.

Trabajos de investigación 1990 / Research works 1990

El estudio surgío con la necesidad de revisar la confiabilidad diagnóstica de los pacientes (82 expedientes primer trimestre 1988) el tratamiento y la evolución hospitalaria que se ha brindado a pacientes con diagnóstico de esquizofrenia, siendo que este diagnóstico es uno de los más frecuentes en el Hospital Psiquiátrico "Fray Bernardino Alvares". Se encuestaron 44 pacientes masculinos y 38 del sexo femenino, 30-36 promedio de edad, escolaridad 15.9% primaria completa, 13.4% con secundaria, 7.3% con preparatoria, 2.4% educación profesional y 2.4% analfabeta; 56.1% no tenian ocupación, la mayoria provenian del D.F. o Valle de México; 74.4% su estado civil eran solteros, 23 pacientes se hospitalizaron por primera vez; 32 pacientes provenian de familias desintegradas, 25 de familias integradas y 2 no se corroboró. El promedio de estancia en el hospital es de 68-93 días. El uso de fármacos demostró que la perfenazina tuvo un 92% de resultados satisfactorios,los medicamentos más usados fueron los neviolepticos (125 ocasiones). A su egreso se ha controlado el brote agudo de enfermedad y diagnóstico emitido es concordante en un 71% con el

Estudio comparativo de programas de postgrado en psiquiatría en México / Comparative study of posgraduate psyquiatric programs in Mexico

Análisis en cinco universidades donde cuentan con programas de postgrado en psiquiátria, se revisó el perfíl educativo de dichos programas, las universidades fueron: Universidad Nacional Autónoma de México (U.N.A.M.), Universidad de Guadalajara (U. de G.), Universidad Autónoma de Nuevo León (U.A.N.L.), Universidad del Ejercito y la Fuerza Aerea (U.D.E.F.A.) y la Universidad Autónoma de Guadalajara (U.A. de G.). La UNAM fue la que contó con 10,060 hrs. de práctica clínica y carga académica; la U de G tiene predominio en materias psicológicas con 540 hrs, en materias biológicas la UAG con 230 hrs., en cuanto a materias sociales el dominio es bajo con 100 hrs. En el Primer año predominó las materias básicas a las clínicas excepto en la UNAM; hay aumento de éstas para el segundo año, predomina el área psicológica en UANL, UDEFA y U de G