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Abstract Cyclin-dependent kinases 4 and 6 (CDK4/6) play a pivotal role in cell cycle and cancer development. Targeting CDK4/6 has demonstrated promising effects against breast cancer. However, resistance to CDK4/6 inhibitors (CDK4/6i), such as palbociclib, remains a substantial challenge in clinical settings. Using high-throughput combinatorial drug screening and genomic sequencing, we find that the microphthalmia-associated transcription factor (MITF) is activated via O-GlcNAcylation by O-GlcNAc transferase (OGT) in palbociclib-resistant breast cancer cells and tumors. Mechanistically, O-GlcNAcylation of MITF at Serine 49 enhances its interaction with importin α/β, thus promoting its translocation to nuclei, where it suppresses palbociclib-induced senescence. Inhibition of MITF or its O-GlcNAcylation re-sensitizes resistant cells to palbociclib. Moreover, clinical studies confirm the activation of MITF in tumors from patients who are palbociclib-resistant or undergoing palbociclib treatment. Collectively, our studies shed light on the mechanism regulating palbociclib resistance and present clinical evidence for developing therapeutic approaches to treat CDK4/6i-resistant breast cancer patients.

Las malformaciones congénitas son la principal causa de muerte neonatal precoz en nuestro medio; en la mayoría de los casos corresponden a cardiopatías congénitas mayores. Las cardiopatías congénitas tienen una incidencia de 8/1.000 recién nacidos vivos, correspondiendo la mitad de ellas a cardiopatías congénitas mayores. Una de las intervenciones recomendadas para reducir la mortalidad de este grupo de niños es evaluar rutinariamente la anatomía del corazón fetal mediante ecografía obstétrica, para planificar la atención neonatal, de aquellos fetos con cardiopatías congénitas, en el momento y lugar más oportuno. En objetivo de la presente revisión es comprobar si el diagnóstico prenatal de una cardiopatía congénita mejora el pronóstico perinatal respecto de aquellos casos que son diagnosticados post parto. Observamos que el diagnóstico antenatal de cardiopatía congénita, no mejora la sobrevida neonatal, excepto en ciertas cardiopatías congénitas ductus dependientes (transposición de grandes arterias, hipoplasia del corazón izquierdo y coartación de aorta), en que si se ha reportado una mayor probabilidad de sobrevida en el grupo de recién nacidos en los cuales se realizó el diagnóstico en el período prenatal. Recomendamos la evaluación rutinaria del corazón fetal en la ecografía obstétrica habitual, y efectuar ecocardiografía fetal especializada ante la sospecha de alteraciones o en aquellos grupos de mayor riesgoCongenital malformations are the main cause of neonatal death; in most of the cases they correspond to major congenital heart defects. Congenital heart defects have an incidence of 8/1,000 live newborns, corresponding half of them to major congenital heart defects. To reduce the mortality of this group of children routine evaluation of fetal heart anatomy by ultrasound is recommended, allowing neonatal care, of those fetuses with congenital heart defects, at the appropriate time and place. Here we attempt to verify if prenatal diagnosis of a congenital heart defect improves the perinatal outcome compare to postnatal diagnosis. We observed that the prenatal diagnosis of congenital heart defects, does not improve the neonatal outcome, except in certain congenital ductus dependent heart defects (transposition of great vessels, hypoplastic left heart syndrome and aortic coarctation), where a better outcome has been shown for those new born with prenatal diagnosis. We recommend routine evaluation of the fetal heart during prenatal ultrasound, and to carry out fetal echocardiography in high risk groups or when a defect is suspected

La incidencia de diabetes gestacional varía notablemente según el origen étnico del grupo evaluado. Se discute la necesidad de realizar screening en el embarazo y el método a utilizar. Este estudio compara dos grupos de 4.944 y 2.385 embarazadas que en periodos distintos, fueron sometidas a screening para diabetes gestacional. El primero según el esquema propuesto por la American Diabetes Association (ADA) y el segundo por la Organización Mundial de la Salud (OMS) y adoptado por el Ministerio de Salud de Chile (MINSAL) en 1998. Se observó que la incidencia de diabetes gestacional en el grupo según criterio ADA fue de 3,18%, mientras que en el grupo según criterio OMS fue de 7,72%. Asimismo, la incidencia de complicaciones asociadas a diabetes gestacional, tales como, fetos grandes para la edad gestacional, hipoglicemia neonatal e hipertensión del embarazo, fueron más frecuentes en diabéticas gestacionales según criterio ADA que en aquellas según criterio OMS. En contraste, no se observo diferencia entre ambos grupos en lo relativo a traumatismo obstétrico, asfixia neonatal y tasas de cesáreaThe incidence of gestational diabetes has a wide range from each ethnic group to another. In the latest years has been controversy about the convenience of make screening test for gestational diabetes and about the best test to do it. The present report compares two groups of 4944 and 2385 patients, who were tested for gestational diabetes at different times. The first group was tested with American Diabetes Association (ADA) method and the other group with World Health Organization (WHO) method, this one was adopted by National Health Ministry of Chile in 1998. The incidence of gestational diabetes was 3.18% in the group tested by ADA method in contrast to 7.72% in the group tested by WHO method. Therefore, the incidence of complications associated with gestacional diabetes, such as, birth weight above the 90th percentile, hypoglycemia and hypertension induced by pregnancy, were more frequent in diabetic patients from ADA method than WHO method. In contrast to this, there were not differences between both groups related to obstetric traumatism, neonatal asphyxia and cesarean rates

fluctúa entre 1 y 3 por 1000 recién nacidos vivos. Se han entregado pautas dirigidas a reducir las tasas de sepsis precoz con la administración de antibióticos intraparto. Se ha propuesto como antibiótico de primera elección la Penicilina o Ampicilina, y Clindamicina para pacientes alérgicos a las primeras, pero también se ha planteado el uso de Eritromicina o Cefazolina. Se estudia la sensibilidad a estas drogas, en 183 cepas de Streptococcus Grupo B, aisladas en 917 embarazadas, al final del tercer trimestre, en región vaginal y pStreptococcus agalactiae (Grupo B Streptococcus) is the main bacterial agent involved in neonatal sepsis of early onset (1 to 3/1000 live newborns). Has been given standards for reducing the rates of neonatal sepsis of early onset using antibiotics during labor. Has been proposed as the first choice Penicilin or Ampicilin and Clindamicin for allergic patients. Erythromycin and Cefazolin has been proposed to treat this patients. This report study sensibilities for this drugs in 183 Group B Streptococcus strains from vaginal and perianal region of 917 pregnant women during the last trimester

La infección urinaria es la patología infecciosa más frecuente en el embarazo. Puede producir graves consecuencias para la madre y el feto. El presente trabajo muestra la frecuencia de los distintos cuadros clínicos, agentes involucrados, antimicrobianos utilizados en el tratamiento, y sensibilidad de los agentes a dichas drogas, durante el período entre marzo y diciembre de 2001. Se comparan dichos resultados con lo publicado por nuestro centro en 1988. Destaca la disminución en la incidencia de pielonefritis aguda y la aparición en los microorganismos de resistencia significativa a la cefazolina en el último período.Urinary tract infection is the most common infectious disease during pregnancy with serious consequences for mother and fetus. The present report shows clinical presentation, bacterial agents involved, treatment used and antibacterial sensitivity, from march to december 2001, and compares this with our own report of 1988. Remarkable is a decrasing incidence of pyelonephritis in the last period and increasing bacterial resistance to cefazolina in the last period.

La rotura uterina se presenta habitualmente en pacientes con cicatriz de cesáreas previas, siendo la rotura de un útero sin cicatriz un fenómeno infrecuente, pero de graves consecuencias para la madre y el feto. Presentamos nuestra experiencia reciente, detallando el manejo y resultados maternos y fetales.Uterine ruptures is more common in women with previous cesarean deliveries, ruptures in unscarred uterus are unfrequent, but with serious consequences for the mother and fetus. This report shows our recent experience, and describes treatment, and maternal and fetal outcomes.

El tratamiento de la metrorragia postparto contempla enfoques quirúrgicos conservadores para aquellas pacientes en quienes se desea conservar la fertilidad. En ellas la ligadura de arterias hipogástricas muestra buenos resultados en el control del sangrado, además ha mostrado éxito en lograr embarazos posteriores. Se presenta un caso clínico manejado por los autores y se analiza la literatura disponibleTreatment for postpartum hemorrhage had conservative approaches for patients that want to preserve fertility. In those patients hypogastric arteries ligations show good results and good prognosis for future pregnancies. This case report shows our experience and review of the literature

Copyright of Revista Chilena de Obstetricia y Ginecología is the property of Revista Chilena de Obstetricia y Ginecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Phenylene bis-pyrazolone derivatives were obtained by condensation of two aromatic β-diketo diesters with methyl-, 2-hydroxyethyl- and phenylhydrazines. The pyrazolone rings are connected to the central benzene ring by their C-3, leaving C-4 free for further . Thus, and despite their low solubility, these compounds were successfully nitrosated in good yield providing new chelating dioximes. [ABSTRACT FROM AUTHOR]

The synthesis, characterisation and mesomorphic properties of new liquid crystals are reported. The goal was to obtain amides starting from 7-decanoyloxychromone-3-carboxylic acid and 4-n-alkoxyanilines. However, instead of the expected amides, in each case a mixture of two isomeric E/Z enaminones was isolated, with a ratio 3/1. The mesophase behaviour of the five mixtures was characterised and studied using differential scanning calorimetry and polarising optical microscopy. The transitions are enantiotropic, the peaks being sharp and the mesomorphic range wide. All the compounds exhibit a smectic C phase and the derivatives with shorter chains also exhibit a nematic phase. [ABSTRACT FROM AUTHOR]

Copyright of Revista Chilena de Obstetricia y Ginecología is the property of Revista Chilena de Obstetricia y Ginecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The synthesis and liquid crystalline properties of a new series of calamitic liquid crystals containing 4-H-benzopyran-4-one (chromone) within the central core is reported. The first homologue in the series display SmA phase ( 8a ), the homologues ( 8b - e ) exhibit SmA and SmC mesophases and the homologues ( 8f - h ) exhibit only a SmC mesophase. [ABSTRACT FROM AUTHOR]

Two series of calamitic liquid crystals containing a benzothiazole ring within the central core and two different linkage groups (amide and azo) have been prepared and their liquid crystalline properties studied and compared with those of the analogous series of imines. The influence of the linkage group within the central core has been proven to determine the variety of mesomorphism displayed by the compounds. The compounds with imine and azo linkages behave in a similar way and exhibit typical nematic and smectic C mesophases. Compounds incorporating an amide linkage show a poorer mesomorphism and mainly present a smectic C mesophase. [ABSTRACT FROM AUTHOR]

Two new series of calamitic liquid crystals containing the isoflavone moiety within the central core have been prepared and their liquid crystalline properties studied. The compounds exhibit typical nematic, smectic A and C mesophases. The influence of the linking group between a terminal alkyl chain and the central core has been proven to determine the variety of mesomorphism displayed by the compounds. [ABSTRACT FROM AUTHOR]

Thesyntheses of N-4-n-alkoxyphenyl-6-n-decyloxyquinoline-2-carboxamide(alkoxy=CnH2n+1O, n=4-10) and 4-n-alkoxyphenyl-6-n-decyloxyquinoline-2-carboxylate (n=4,6,8) are described along with the measurement of their physical properties using DSC and optical methods. The amides all show an enantiotropic smectic A phase while the esters show monotropic mesophases. A study of the structure/mesomorphic activity relationship is also described. [ABSTRACT FROM AUTHOR]

Prenatal malnutrition results in increased concentration and release of central noradrenaline, a neurotransmitter that is an important regulator of normal regressive events such as axonal pruning and synaptic elimination. This suggests that some of the functional disturbances in brain induced by prenatal malnutrition could be due at least in part to increased noradrenaline activity that may enhance regressive events during early stages of development. To test this hypothesis we studied whether chronic administration of alpha-methyl-p-tyrosine, an inhibitor of tyrosine hydroxylase, to rats during gestation might prevent long-term deleterious effects of prenatal malnutrition on functional properties of interhemispheric connections of the visual cortex, and on asymmetry of visual evoked responses. The experiments were conducted on normal and malnourished rats 45-50 d of age. Prenatal malnutrition was induced by restricting the food consumption of pregnant rats to 40%, from d 8 postconception to parturition. At birth, prenatally malnourished rats had significantly greater whole-brain noradrenaline concentration as well as significantly enhanced noradrenaline release in the visual cortex. At 45-50 d of age, the malnourished group had a significantly smaller cortical area, exhibiting transcallosal evoked responses; in addition, the amplitude of these responses was significantly smaller. Malnourished rats showed a significant reduction of the normal interhemispheric asymmetry of visual evoked responses. The addition of 0.3% alpha-methyl-p-tyrosine to the diet of malnourished pregnant rats during the last 2 wk of gestation prevented functional disorders induced in the offspring by prenatal malnutrition on interhemispheric connectivity of visual areas and on interhemispheric bioelectrical asymmetry, probably by reducing the elevated brain noradrenaline activity and thereby restoring the normal trophic role of this neurotransmitter. [ABSTRACT FROM AUTHOR]