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1.
J Hand Surg Am ; 47(10): 979-987, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35534325

RESUMEN

PURPOSE: We sought to determine the effectiveness of corticosteroid injections (CSIs) for de Quervain tenosynovitis in patients with diabetes mellitus. METHODS: We retrospectively identified all patients with diabetes receiving a CSI for de Quervain tenosynovitis by 16 surgeons over a 2-year period. Data collected included demographic information, medical comorbidities, number and timing of CSIs, and first dorsal compartment release. Success was defined as not undergoing an additional CSI or surgical intervention. The mixture of a corticosteroid and local anesthetic provided in each injection was at the discretion of each individual surgeon. RESULTS: Corticosteroid injections were given to 169 wrists in 169 patients with diabetes. Out of 169 patients, 83 (49%) had success following the initial CSI, 44 (66%) following a second CSI, and 6 (67%) following a third CSI. A statistically significant difference was identified in the success rates between the first and second CSIs. Ultimately, 36 of 169 wrists (21%) underwent a first dorsal compartment release. CONCLUSIONS: Patients with diabetes mellitus have a decreased probability of success following a single CSI for de Quervain tenosynovitis in comparison to nondiabetic patients, as described in the literature. However, the effectiveness of each additional CSI does not appear to diminish. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.


Asunto(s)
Enfermedad de De Quervain , Diabetes Mellitus , Tenosinovitis , Corticoesteroides/uso terapéutico , Anestésicos Locales/uso terapéutico , Enfermedad de De Quervain/tratamiento farmacológico , Enfermedad de De Quervain/cirugía , Humanos , Estudios Retrospectivos , Tenosinovitis/tratamiento farmacológico
2.
Cryobiology ; 95: 15-19, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32619521

RESUMEN

A number of studies have explored the use of membrane permeable (usually metabolizable) and membrane impermeable saccharides to protect cells in general, and sperm in particular during cryopreservation. Critical concentrations for protective levels of sugars frequently range between 50 mmol/L and 500 mmol/L, where efficacy is attributed to the sugar's membrane stabilizing and glass forming attributes and colligative effects that reduce intra- and extracellular salt concentrations during freezing. Many studies on bull sperm have demonstrated that both permeating and non-permeating sugars have negligible positive effects on post-thaw viability. Recently, however, a non-metabolizable sugar, 3-O-Methylglucose (3-OMG), was shown to protect hepatocytes during liver cryopreservation at 0.1-0.3 mol/L. Because glucose is readily transported into sperm, we hypothesized that 3-OMG could be a new class of cryoprotectant to explore in bull sperm. Here we present positive results demonstrating that 3-OMG improves post thaw viability in bull sperm, and that this effect is not likely due to improved glass forming capabilities. In particular, in experiment 1, 3-OMG was added to the Tris-egg yolk-glycerol base media at levels from 0 mmol/L to 200 mmol/L. Semen from four bulls was collected and diluted with one of the cryopreservation media, cooled, and frozen following industry standard practices. Motility and mitochondrial activity were negatively impacted when concentration of 3-OMG was more than 25 mmol/L. Therefore, we explored lower concentrations in experiment 2, where semen from eight bulls was used to evaluate concentrations 5 mmol/L, 15 mmol/L and 25 mmol/L of 3-OMG compared with control. Motility and progressive motility in 5 mmol/L 3-OMG and in the control were significantly higher than 15 mmol/L and 25 mmol/L 3-OMG, whereas mitochondrial activity and acrosome integrity in 5 mmol/L 3-OMG were significantly better than the control freezing medium. In experiment 3, to evaluate whether the improved effects of 3-OMG are due to its non-metabolizing property, or due to colligative effects, we compared post-thaw viability in semen from four bulls cryopreserved with 5 mmol/L glucose, sucrose, or 3-OMG. Motility and progressive motility was significantly improved in 3-OMG compared to glucose or sucrose groups which were comparable to the EY control. In conclusion, 3-OMG at a concentration of 5 mmol/L in Tris-egg yolk-glycerol medium improves the post thaw motility, progressive motility and viability of bull sperm. The mechanism of action is not understood but because the efficacy is maximal at low concentrations, it is not likely due to improved intra- or extracellular glass forming abilities and may demonstrate a different protective mechanism than was shown in hepatocytes.


Asunto(s)
Criopreservación , Preservación de Semen , 3-O-Metilglucosa , Animales , Bovinos , Criopreservación/métodos , Crioprotectores/farmacología , Humanos , Masculino , Preservación de Semen/veterinaria , Motilidad Espermática , Espermatozoides
3.
Z Geburtshilfe Neonatol ; 224(4): 181-186, 2020 08.
Artículo en Alemán | MEDLINE | ID: mdl-32838447

RESUMEN

The novel coronavirus SARS-CoV-2 has developed into a pandemic, yet still has many unknowns. The modalities of transmission, different symptoms and manifestations as well as concomitant circumstances of the disease are insufficiently characterized. Especially patient groups in special situations like pregnant women and newborns have to be considered separately. The current knowledge about pregnancy, labor and the first days of life is characterized by particular uncertainty due to the scarce data available. However, there is currently no evidence of significant unfavorable maternal and perinatal outcome. Many pregnant women with SARS-CoV-2 infection remain asymptomatic. The possibility of vertical transmission to the child cannot be excluded with certainty. However, indications of vertical transmission were detected only in individual cases. Newborn infections are also rather rare, unspecific and usually mild, with respiratory symptoms dominating. In this article, the data available to date are examined in order to provide better information, advice and treatment for pregnant women and newborns with SARS-CoV-2 and to provide suggestions for future research.


Asunto(s)
Infecciones por Coronavirus/prevención & control , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Pandemias , Atención Perinatal , Neumonía Viral/prevención & control , Complicaciones Infecciosas del Embarazo/virología , Betacoronavirus , COVID-19 , Niño , Infecciones por Coronavirus/epidemiología , Femenino , Humanos , Recién Nacido , Neumonía Viral/epidemiología , Embarazo , SARS-CoV-2
4.
Mol Reprod Dev ; 86(8): 999-1012, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31134708

RESUMEN

In the context of artificial insemination, male fertility is defined as the ability to produce functional spermatozoa able to withstand cryopreservation. We hypothesized that interindividual variations in fertility depend on the proportion of the fully functional sperm population contained in the insemination dose. The objective of this study was to identify protein markers of the fully functional sperm subpopulation. Insemination doses from four high-fertility (HF) and four low-fertility (LF) bulls with comparable post-thaw quality parameters were selected for proteomic analysis using iTRAQ technology. Thawed semen was centrifuged through a Percoll gradient to segregate the motile (high density [HD]) from the immotile (low density [LD]) sperm populations. Sperm proteins were extracted with sodium deoxycholate and four groups were compared: LD and HD spermatozoa from LF and HF bulls. A total of 498 unique proteins were identified and quantified. Comparison of HD spermatozoa from HF and LF bulls revealed that five proteins were significantly more abundant in the HF group (AK8, TPI1, TSPAN8, OAT, and DBIL5) whereas five proteins were more abundant in the LF group (RGS22, ATP5J, CLU, LOC616319, and CCT5). Comparison of LD spermatozoa from HF and LF bulls revealed that four proteins were significantly more abundant in the HF group (IL4I1, CYLC2, OAT, and ARMC3) whereas 15 proteins were significantly more abundant in the LF group (HADHA, HSP90AA1, DNASE1L3, SLC25A20, GPX5, TCP1, HIP1, CLU, G5E622, LOC616319, HSPA2, NUP155, DPY19L2, SPERT, and SERPINE2). DBIL5, TSPAN8, and TPI1 showed potential as putative markers of the fully functional sperm subpopulation.


Asunto(s)
Antígenos de Diferenciación/metabolismo , Separación Celular , Centrifugación Isopicnica , Fertilidad , Povidona/química , Dióxido de Silicio/química , Espermatozoides , Animales , Bovinos , Masculino , Espermatozoides/citología , Espermatozoides/metabolismo
5.
Bioorg Med Chem Lett ; 29(21): 126659, 2019 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-31543303

RESUMEN

Aided by Structure Based Drug Discovery (SBDD), we rapidly designed a highly novel and selective series of mTOR inhibitors. This chemotype conveys exquisite kinase selectivity, excellent in vitro and in vivo potencies and ADME safety profiles. These compounds could serve as good tools to explore the potential of TORC inhibition in various human diseases.


Asunto(s)
Furanos/química , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/metabolismo , Piridinas/química , Pirimidinas/química , Serina-Treonina Quinasas TOR/antagonistas & inhibidores , Unión Competitiva , Descubrimiento de Drogas , Humanos , Modelos Moleculares , Estructura Molecular , Morfolinas/química , Fosfatidilinositol 3-Quinasa/química , Unión Proteica , Relación Estructura-Actividad
6.
Artículo en Inglés | MEDLINE | ID: mdl-38323931

RESUMEN

OBJECTIVE: To compare postoperative opioid consumption with patients who tested negative for tetrahydrocannabinol (THC) preoperatively with those who were THC-positive and patients who were positive for THC and any other drug and to compare 90-day rates of postoperative emergency department (ED) visits and 90-day readmission rates, using morphine milligram equivalents (MMEs), for those three patient populations. METHODS: Three patient groups were confirmed with preoperative urine drug screens. Chart reviews were conducted to determine whether there was an ED visit or hospital readmission 90 days from the index procedure. MMEs were calculated for all patients. RESULTS: There were a total of 252 patients in the THC-negative control group, 54 in the THC-positive group, and 47 in the THC-and-opioid-positive group. The 90-day ED visit and 90-day readmission rates were not statistically significant among the groups. Both the multidrug and THC-only-positive patients showed a higher 90-day MME compared with the control patients. DISCUSSION: Our study demonstrates that THC used may increase opioid consumption. The THC patients to be cautious toward are the multidrug user. Although not statistically significant, multidrug patients were noted for a trend toward increased ED visits and readmissions.


Asunto(s)
Cannabis , Alucinógenos , Humanos , Analgésicos Opioides , Readmisión del Paciente , Visitas a la Sala de Emergencias , Agonistas de Receptores de Cannabinoides
7.
Bioorg Med Chem Lett ; 23(10): 3059-63, 2013 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-23566514

RESUMEN

The synthesis and biological evaluation of novel Tie-2 kinase inhibitors are presented. Based on the pyrrolopyrimidine chemotype, several new series are described, including the benzimidazole series by linking a benzimidazole to the C5-position of the 4-amino-pyrrolopyrimidine core and the ketophenyl series synthesized by incorporating a ketophenyl group to the C5-position. Medicinal chemistry efforts led to potent Tie-2 inhibitors. Compound 15, a ketophenyl pyrrolopyrimidine urea analog with improved physicochemical properties, demonstrated favorable in vitro attributes as well as dose responsive and robust oral tumor growth inhibition in animal models.


Asunto(s)
Antineoplásicos/síntesis química , Antineoplásicos/farmacología , Descubrimiento de Drogas , Neoplasias/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/farmacología , Pirimidinas/farmacología , Pirroles/farmacología , Receptor TIE-2/antagonistas & inhibidores , Animales , Antineoplásicos/administración & dosificación , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Humanos , Masculino , Estructura Molecular , Neoplasias/enzimología , Neoplasias/patología , Inhibidores de Proteínas Quinasas/administración & dosificación , Pirimidinas/síntesis química , Pirimidinas/química , Pirroles/síntesis química , Pirroles/química , Ratas , Ratas Sprague-Dawley , Receptor TIE-2/metabolismo , Relación Estructura-Actividad , Ensayos Antitumor por Modelo de Xenoinjerto
8.
J Vasc Surg Venous Lymphat Disord ; 11(6): 1203-1212, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37473870

RESUMEN

BACKGROUND: The plantar venous pump (PVP), composed of deep plantar veins, is the most distal contributor to venous return from the lower limbs. A pressing need still exists to assess how plantar muscle contraction and gait affect PVP function, how foot stato-dynamic disorders (FSDs) can contribute to venous insufficiency, and how venous return can be optimally stimulated. Our first objective is to compare the venous blood hemodynamics in lower limbs between healthy subjects with a FSD and healthy subjects without a FSD to understand the influence of foot morphology in the performance of the PVP. Our second objective is to evaluate whether PVP function varies with different plantar pressures. METHODS: A total of 52 healthy volunteers (26 feet with a normal arch as the control group and 26 feet with dysmorphism [13 flat feet and 13 hollow feet]) were included. Strain-gauge plethysmography was performed 8 cm above the medial malleolus at different conditions of PVP stimulation: (1) toe flexion, (2) intermittent pneumatic compression (IPC) with and without an insole, and (3) 3-km/h speed walking on a treadmill barefoot, with shoes, and with shoes and insoles. From the strain-gauge plethysmography, we measured the venous blood ejection fraction (EF). From the pressure sensor placed at the midfoot on the plantar arch during IPC, we obtained the maximal pressure (N/cm2). RESULTS: Toe flexion allowed for ejection of an average of 20% of the total venous volume in both groups. IPC and gait generated a mean EF superior to 100% of the available venous volume. The maximal pressure applied at the midfoot during IPC was lower than the pressure set. No significant differences in the EF or maximal pressure were observed between the two groups. The mean EF was not significantly affected for the pronator and supinator walkers compared with those with normal walking dynamics. Wearing shoes did not significantly affect the mean EF. However, wearing insoles during gait significantly increased the venous return in feet with plantar dysmorphism. CONCLUSIONS: To the best of our knowledge, this clinical study is the first to assess the PVP function in 52 healthy volunteers with and without FSDs. We found that wearing shoes did not significantly affect PVP efficiency but that wearing morphologically adapted insoles significantly improved the venous return in the dysmorphic feet. In our sample of healthy volunteers, the differences observed between the control group and feet with FSDs were not statistically significant.

9.
Phlebology ; 38(6): 380-388, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37204862

RESUMEN

BACKGROUND: The role of the plantar venous pump (PVP) on venous return is evident but the effects of the foot morphology have never been characterized properly. METHOD: 52 healthy volunteers-26 with normal plantar arch (control) and 26 with dysmorphic plantar arch (in two subgroups: 13 flat feet, 13 hollow feet)-were included. Using Doppler ultrasound, we measured the diameter and the peak systolic velocity in the large veins of the lower limb after PVP stimulation by manual compression and bodyweight transfer. RESULT: The mean peak systolic velocity of the studied veins varied from 12.2 cm/s to 41.7 cm/s in the control group and from 10.9 cm/s to 39.1 cm/s in the dysmorphic plantar group. The foot arch morphology did not affect significantly the venous blood flows, except in the great saphenous vein during manual compression. CONCLUSION: The plantar morphology did not induce a significant increase of venous blood velocity resulting from PVP stimulation.


Asunto(s)
Pie , Extremidad Inferior , Humanos , Pie/irrigación sanguínea , Hemodinámica/fisiología , Vena Femoral/fisiología , Ultrasonografía
10.
ACS Med Chem Lett ; 14(11): 1544-1550, 2023 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-37970587

RESUMEN

The mTOR kinase regulates a variety of critical cellular processes and has become a target for the treatment of various cancers. Using a combination of property-based drug design and Free-Wilson analysis, we further optimized a series of selective mTOR inhibitors based on the (S)-6a-methyl-6a,7,9,10-tetrahydro[1,4]oxazino[3,4-h]pteridin-6(5H)-one scaffold. Our efforts resulted in 14c, which showed similar in vivo efficacy compared to previous lead 1 at 1/15 the dose, a result of its improved drug-like properties.

11.
Anim Reprod Sci ; 245: 107065, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36115090

RESUMEN

There is considerable interest in breeding programs to "rescue" semen with poor post-thaw fertility from bulls known as "bad freezers". We hypothesized that there may be an interaction between the post-thaw recovery of sperm and the efficacy of antioxidant addition to extenders. The current study assesses the effects of antioxidant additives hydroxytyrosol (HT) and resveratrol (RSV) on the post-thaw semen parameters in two groups of bulls classified as either high or low cryotolerant (i.e., "good" and "bad" freezers). Semen samples were collected from 40 bulls and processed in the extenders containing different concentrations of HT (experiment 1; 0, 25 and 50 µM) and RSV (experiment 2; 0.0, 0.01, 0.1 and 1 mM). In experiment 1, bulls in the low cryotolerance group had a significant improvement in post-thaw recovery at 25 µM and 50 µM (P < 0.05). These improvements were observed in motility and several cellular parameters. However, post-thaw semen quality in the high cryotolerance group was not significantly affected by the HT addition. In experiment 2, although RSV did not have any positive impact in high cryotolerance group, post-thaw recovery in the low cryotolerance bulls was significantly improved in 0.1 mM RSV. Oxidative stress markers in either high or low cryotolerance groups were not significantly changed by RSV addition (P > 0.05). It can be concluded that addition of optimized concentrations of HT and RSV to the extender could be a strategy for improving the post-thaw semen, especially in bulls with high genetic merit but low initial cryotolerance.


Asunto(s)
Preservación de Semen , Semen , Animales , Antioxidantes/farmacología , Búfalos , Bovinos , Criopreservación/veterinaria , Crioprotectores/farmacología , Masculino , Alcohol Feniletílico/análogos & derivados , Resveratrol/farmacología , Análisis de Semen/veterinaria , Preservación de Semen/veterinaria , Motilidad Espermática , Espermatozoides
12.
Sci Rep ; 12(1): 22328, 2022 12 25.
Artículo en Inglés | MEDLINE | ID: mdl-36567337

RESUMEN

Cryopreservation provides a critical tool for dairy herd genetics management. Due to widely varying inter- and within-bull post thaw fertility, recent research on cryoprotectant extender medium has not dramatically improved suboptimal post-thaw recovery in industry. This progress is stymied by the interactions between samples and the many components of extender media and is often compounded by industry irrelevant sample sizes. To address these challenges, here we demonstrate blank-slate optimization of bull sperm cryopreservation media by supervised machine learning. We considered two supervised learning models: artificial neural networks and Gaussian process regression (GPR). Eleven media components and initial concentrations were identified from publications in bull semen cryopreservation, and an initial 200 extender-post-thaw motility pairs were used to train and 32 extender-post-thaw motility pairs to test the machine learning algorithms. The median post-thaw motility after coupling differential evolution with GPR the increased from 52.6 ± 6.9% to 68.3 ± 6.0% at generations 7 and 17 respectively, with several media performing dramatically better than control media counterparts. This is the first study in which machine learning was used to determine the best combination of constituents to optimize bull sperm cryopreservation media, and provides a template for optimization in other cell types.


Asunto(s)
Preservación de Semen , Semen , Masculino , Animales , Bovinos , Análisis de Semen/veterinaria , Motilidad Espermática , Preservación de Semen/veterinaria , Espermatozoides , Criopreservación/veterinaria , Crioprotectores , Aprendizaje Automático
13.
Biol Reprod ; 84(6): 1128-38, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21325692

RESUMEN

Despite recent advances in the derivation of rat embryonic stem cells, clear comprehension of the timing and mechanisms underlying rat early embryo lineage selection is lacking. We have previously shown the in vivo contribution of rat embryonic stem-like cells exclusively to developing extraembryonic tissues. To elucidate possible mechanisms governing the in vitro and in vivo behaviors of these rat blastocyst-derived stem cells, we evaluated their developmental capacity by using several approaches. Molecular marker analysis demonstrated the expression profile of genes characterizing not only pluripotency but also extraembryonic endoderm and trophoblast. In vitro differentiation through embryoid body formation showed in vitro pluripotent capacity through differentiation into derivatives of all three embryonic germ layers. Following either blastocyst injection, diploid or tetraploid aggregation, and embryo transfer, these rat blastocyst-derived stem cells also demonstrated in vivo multipotency through contribution to multiple developmentally distinct extraembryonic lineages. Features of phenotypic heterogeneity were revealed following examination of cell line morphology and culture behavior, as well as quantitative analysis of marker expression in discrete undifferentiated and differentiated populations of cells by flow cytometry. We demonstrate for the first time that stem cells derived from the rat blastocyst have the ability to contribute to the embryonic and extraembryonic lineages. Together, these results provide a valuable new model for rat stem cell biology and for the elucidation of early lineage selection in the embryo.


Asunto(s)
Blastocisto/citología , Células Madre Embrionarias/fisiología , Membranas Extraembrionarias/citología , Células Madre Pluripotentes/citología , Animales , Técnicas de Cultivo de Célula , Diferenciación Celular , Células Cultivadas , Femenino , Perfilación de la Expresión Génica , Regulación del Desarrollo de la Expresión Génica/fisiología , Células Madre Pluripotentes/fisiología , Embarazo , Ratas
14.
Reproduction ; 141(3): 321-32, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21209071

RESUMEN

Although putative horse embryonic stem (ES)-like cell lines have been obtained recently from in vivo-derived embryos, it is currently not known whether it is possible to obtain ES cell (ESC) lines from somatic cell nuclear transfer (SCNT) and parthenogenetic (PA) embryos. Our aim is to establish culture conditions for the derivation of autologous ESC lines for cell therapy studies in an equine model. Our results indicate that both the use of early-stage blastocysts with a clearly visible inner cell mass (ICM) and the use of pronase to dissect the ICM allow the derivation of a higher proportion of primary ICM outgrowths from PA and SCNT embryos. Primary ICM outgrowths express the molecular markers of pluripotency POU class 5 homeobox 1 (POU5F1) and (sex determining region-Y)-box2 (SOX2), and in some cases, NANOG. Cells obtained after the passages of PA primary ICM outgrowths display alkaline phosphatase (AP) activity and POU5F1, SOX2, caudal-related homeobox-2 (CDX2) and eomesodermin (EOMES) expression, but may lose NANOG. Cystic embryoid body-like structures expressing POU5F1, CDX2 and EOMES were produced from these cells. Immunohistochemical analysis of equine embryos reveals the presence of POU5F1 in trophectoderm, primitive endoderm and ICM. These results suggest that cells obtained after passages of primary ICM outgrowths are positive for trophoblast stem cell markers while expressing POU5F1 and displaying AP activity. Therefore, these cells most likely represent trophoblast cells rather than true ESCs. This study represents an important first step towards the production of autologous equine ESCs for pre-clinical cell therapy studies on large animal models.


Asunto(s)
Biomarcadores/metabolismo , Masa Celular Interna del Blastocisto/metabolismo , Caballos , Partenogénesis/genética , Células Madre/metabolismo , Trofoblastos/metabolismo , Animales , Biomarcadores/análisis , Masa Celular Interna del Blastocisto/citología , Masa Celular Interna del Blastocisto/fisiología , Bovinos , Técnicas de Cultivo de Célula , Procesos de Crecimiento Celular/fisiología , Forma de la Célula , Células Cultivadas , Embrión de Mamíferos , Factor de Transcripción GATA6/genética , Factor de Transcripción GATA6/metabolismo , Expresión Génica , Caballos/genética , Caballos/metabolismo , Caballos/fisiología , Técnicas de Transferencia Nuclear , Factor 3 de Transcripción de Unión a Octámeros/genética , Factor 3 de Transcripción de Unión a Octámeros/metabolismo , Partenogénesis/fisiología , Células Madre/citología , Trofoblastos/citología
15.
J Cell Biol ; 168(5): 801-12, 2005 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-15728190

RESUMEN

Phosphatidylinositol (PtdIns) transfer proteins (PITPs) regulate signaling interfaces between lipid metabolism and membrane trafficking. Herein, we demonstrate that AtSfh1p, a member of a large and uncharacterized Arabidopsis thaliana Sec14p-nodulin domain family, is a PITP that regulates a specific stage in root hair development. AtSfh1p localizes along the root hair plasma membrane and is enriched in discrete plasma membrane domains and in the root hair tip cytoplasm. This localization pattern recapitulates that visualized for PtdIns(4,5)P2 in developing root hairs. Gene ablation experiments show AtSfh1p nullizygosity compromises polarized root hair expansion in a manner that coincides with loss of tip-directed PtdIns(4,5)P2, dispersal of secretory vesicles from the tip cytoplasm, loss of the tip f-actin network, and manifest disorganization of the root hair microtubule cytoskeleton. Derangement of tip-directed Ca2+ gradients is also apparent and results from isotropic influx of Ca2+ from the extracellular milieu. We propose AtSfh1p regulates intracellular and plasma membrane phosphoinositide polarity landmarks that focus membrane trafficking, Ca2+ signaling, and cytoskeleton functions to the growing root hair apex. We further suggest that Sec14p-nodulin domain proteins represent a family of regulators of polarized membrane growth in plants.


Asunto(s)
Arabidopsis/crecimiento & desarrollo , Membrana Celular/metabolismo , Proteínas de Transferencia de Fosfolípidos/metabolismo , Raíces de Plantas/crecimiento & desarrollo , Actinas/metabolismo , Secuencia de Aminoácidos , Calcio/metabolismo , Citoplasma/ultraestructura , Citoesqueleto/metabolismo , Genes Reporteros , Microscopía Electrónica , Datos de Secuencia Molecular , Raíces de Plantas/ultraestructura , Estructura Terciaria de Proteína
16.
Mol Cancer Ther ; 7(7): 1880-9, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18606718

RESUMEN

Signaling through the erbB receptor family of tyrosine kinases contributes to the proliferation, differentiation, migration, and survival of a variety of cell types. Abnormalities in members of this receptor family have been shown to play a role in oncogenesis, thus making them attractive targets for anticancer treatments. PF-00299804 is a second-generation irreversible pan-erbB receptor tyrosine kinase inhibitor currently in phase I clinical trials. PF-00299804 is believed to irreversibly inhibit erbB tyrosine kinase activity through binding at the ATP site and covalent modification of nucleophilic cysteine residues in the catalytic domains of erbB family members. Oral administration of PF-00299804 causes significant antitumor activity, including marked tumor regressions in a variety of human tumor xenograft models that express and/or overexpress erbB family members or contain the double mutation (L858R/T790M) in erbB1 (EGFR) associated with resistance to gefitinib and erlotinib. Furthermore, PF-00299804 shows exceptional distribution to human tumor xenografts and excellent pharmacokinetic properties across species.


Asunto(s)
Antineoplásicos/farmacología , Antineoplásicos/farmacocinética , Quinazolinonas/farmacología , Quinazolinonas/farmacocinética , Proteínas Tirosina Quinasas Receptoras/antagonistas & inhibidores , Ensayos Antitumor por Modelo de Xenoinjerto , Sustitución de Aminoácidos , Animales , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Receptores ErbB/metabolismo , Femenino , Humanos , Ratones , Ratones SCID , Mutación/genética , Fosforilación/efectos de los fármacos , Especificidad de la Especie
17.
J Nucl Med ; 49(1): 129-134, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18077531

RESUMEN

UNLABELLED: The purpose of this study was to evaluate the efficacy of CE-355621, a novel antibody against c-Met, in a subcutaneous U87 MG xenograft mouse model using (18)F-FDG small-animal PET. METHODS: CE-355621 or control vehicle was administered intraperitoneally into nude mice (drug-treated group, n = 12; control group, n = 14) with U87 MG subcutaneous tumor xenografts. Drug efficacy was evaluated over 2 wk using (18)F-FDG small-animal PET and compared with tumor volume growth curves. RESULTS: The maximum %ID/g (percentage injected dose per gram of tissue) of (18)F-FDG accumulation in mice treated with CE-355621 remained essentially unchanged over 2 wk, whereas the %ID/g of the control tumors increased 66% compared with the baseline. Significant inhibition of (18)F-FDG accumulation was seen 3 d after drug treatment, which was earlier than the inhibition of tumor volume growth seen at 7 d after drug treatment. CONCLUSION: CE-355621 is an efficacious novel antineoplastic chemotherapeutic agent that inhibits (18)F-FDG accumulation earlier than tumor volume changes in a mouse xenograft model. These results support the use of (18)F-FDG PET to assess early tumor response for CE-355621.


Asunto(s)
Anticuerpos Monoclonales/farmacología , Antineoplásicos/farmacología , Fluorodesoxiglucosa F18/farmacocinética , Proteínas Proto-Oncogénicas c-met/antagonistas & inhibidores , Radiofármacos/farmacocinética , Animales , Línea Celular Tumoral , Antagonismo de Drogas , Glioblastoma , Humanos , Ratones , Ratones Desnudos , Trasplante de Neoplasias , Tomografía de Emisión de Positrones/métodos , Trasplante Heterólogo
18.
Bioorg Med Chem Lett ; 18(11): 3359-63, 2008 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-18456494

RESUMEN

Based on a high throughput screening hit, pyrrolopyrimidine inhibitors of the Akt kinase are explored. X-ray co-crystal structures of two lead series results in the understanding of key binding interactions, the design of new lead series, and enhanced potency. The syntheses of these series and their biological activities are described. Spiroindoline 13j is found to have an Akt1 kinase IC(50) of 2.4+/-0.6 nM, Akt cell potency of 50+/-19 nM, and provides 68% inhibition of tumor growth in a mouse xenograft model (50 mg/kg, qd, po).


Asunto(s)
Antineoplásicos/síntesis química , Antineoplásicos/farmacología , Proteínas Proto-Oncogénicas c-akt/antagonistas & inhibidores , Pirimidinas/síntesis química , Pirimidinas/farmacología , Pirroles/síntesis química , Pirroles/farmacología , Compuestos de Espiro/síntesis química , Compuestos de Espiro/farmacología , Animales , Antineoplásicos/química , Técnicas Químicas Combinatorias , Cristalografía por Rayos X , Modelos Animales de Enfermedad , Diseño de Fármacos , Concentración 50 Inhibidora , Ratones , Conformación Molecular , Estructura Molecular , Pirimidinas/química , Pirroles/química , Compuestos de Espiro/química , Relación Estructura-Actividad
19.
Opt Express ; 15(15): 9817-30, 2007 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-19547332

RESUMEN

The expression of optical forces provoked by an incident light illuminating particles can be deduced from the Lorentz law. It is shown that these forces derive from a scalar potential in the 2D problem and s-polarization, with light propagating in the cross-section plane of the particles, a fact which shows that the separation between gradient and scattering forces could be questioned. This property does not extend to the p-polarization and 3D problem. In the general case, it is shown that one of the components of the optical force is intimately linked with the reactive energy inside the particle. A possible application is given.

20.
Cancer Chemother Pharmacol ; 59(2): 183-95, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16724239

RESUMEN

PURPOSE: Sorafenib tosylate (sorafenib, BAY 43-9006, Nexavar) is a multi-kinase inhibitor that targets tumor cell proliferation and angiogenesis. These studies evaluated the efficacy and tolerability of combinations of sorafenib plus agents used to treat non-small cell lung cancer (NSCLC) using preclinical models of that disease. METHODS: Intravenous (iv) vinorelbine and interperitoneal (ip) cisplatin were administered intermittently (q4d x 3) in combination with sorafenib administered orally (po) once daily for 9 days starting on the same day as the standard agent. In studies with sorafenib and gefitinib, both agents were administered po daily for 10 days starting on the same day. Treatment in all studies was initiated against established sc tumors, and each study was conducted in duplicate. Efficacy was assessed as the delay in tumor growth to a specified size (TGD). RESULTS: Vinorelbine (6.7 mg/kg) and sorafenib (40 mg/kg) produced TGDs of 2.4 and 7.8 days, respectively, in the NCI-H460 NSCLC model. Combination therapy produced a 10.0-day TGD with no increase in toxicity. Combination therapy in the NCI-H23 NSCLC model with the highest evaluated dose levels of sorafenib plus cisplatin was well tolerated and produced TGDs equivalent to those produced by cisplatin alone. Lower dose levels of each agent produced approximately additive TGD's. Combination therapy in the A549 NSCLC model with sorafenib and gefitinib produced TGDs equivalent to that produced by sorafenib alone with no toxicity. Tumor growth in the MDA-MB-231 mammary tumor model, that contains mutations in signal transduction proteins downstream of the EGF receptor (the target of gefitinib) was also inhibited by sorafenib, but not by gefitinib. CONCLUSION: Concurrent administration of sorafenib and vinorelbine, cisplatin or gefitinib was at least as efficacious as the individual agents alone and was well tolerated. These results support the inclusion of sorafenib in clinical trials in NSCLC employing combinations of both cytotoxic and cytostatic agents.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Neoplasias Pulmonares/tratamiento farmacológico , Ensayos Antitumor por Modelo de Xenoinjerto/métodos , Administración Oral , Animales , Antineoplásicos/administración & dosificación , Bencenosulfonatos/administración & dosificación , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Cisplatino/farmacología , Citotoxinas/administración & dosificación , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Femenino , Gefitinib , Humanos , Neoplasias Pulmonares/patología , Ratones , Ratones Desnudos , Niacinamida/análogos & derivados , Compuestos de Fenilurea , Piridinas/administración & dosificación , Quinazolinas/farmacología , Sorafenib , Vinblastina/análogos & derivados , Vinblastina/farmacología , Vinblastina/uso terapéutico , Vinorelbina , Pérdida de Peso/efectos de los fármacos
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