Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 28
Filter
1.
MedEdPORTAL ; 19: 11322, 2023.
Article in English | MEDLINE | ID: mdl-37469525

ABSTRACT

Introduction: Exit surveys among our pediatric residency graduates found 50% were not confident performing required procedures. While procedural competency poses many curricular challenges, simulation is an effective educational modality many programs have adopted, though often only through onetime workshops limited to single procedures, clinical settings, or levels of training. We sought to develop a comprehensive, recurring, yearlong, simulation-based curriculum covering many important pediatric procedures. Methods: We created a longitudinal curriculum of recurring monthly workshops using both low- and high-fidelity simulators, highlighting 17 pediatric procedures. Comprehensive facilitator guides contained equipment lists, instructions, competency checklists, and quizzes for each workshop. Correlation between attendance and confidence was assessed for skills in which residents attended two or more workshops on the same skill. ACGME exit surveys compared graduates' confidence regarding procedural skills before and after curriculum implementation. Results: On exit surveys, graduates who agreed or strongly agreed to feeling comfortable with the procedures in our curriculum improved from 50% to 66% after 2 years, and those who disagreed or strongly disagreed decreased from 40% to 22%. A positive correlation existed between repeated workshop attendance and confidence in many procedures (R2 range, .60-.99). Discussion: Longitudinal simulation is an effective educational modality that increases learner confidence in performing procedures. Our curriculum addresses adult learners' need for repetition and can be adopted by other programs to improve graduates' confidence. The curriculum's sustainability is underscored by use of cost-reducing low-fidelity simulators and comprehensive guides that allow any instructor to conduct the workshop.


Subject(s)
Internship and Residency , Adult , Humans , Child , Curriculum , Education, Medical, Graduate/methods , Educational Measurement , Computer Simulation
2.
Curr Opin Cardiol ; 37(1): 22-29, 2022 01 01.
Article in English | MEDLINE | ID: mdl-34620737

ABSTRACT

PURPOSE OF REVIEW: Atrial fibrillation is a growing public health problem and is associated with an increased risk of comorbidities with enormous socioeconomic implications. This review article focuses on fiscal burden of atrial fibrillation on the healthcare system and economic value of atrial fibrillation ablations brought to the patient and the payers by improvement in outcomes and reduction in treatment costs. RECENT FINDINGS: This article summarizes the recently published studies evaluating the economic impact of atrial fibrillation treatment. Catheter ablation have shown to be the most successful strategy for treatment of defibrillation. However, repeat ablation is associated with higher costs, over and above any subsequent procedural costs, compared with a single ablation procedure for atrial fibrillation. Cryoballoon ablation has been shown to have fewer repeat ablations than radiofrequency ablations, which resulted in overall cost reduction. Improvement in laboratory efficiency, better utilization of laboratory resources and same-day discharge strategy can lead to further healthcare savings and increase in value to all stakeholders. SUMMARY: The value of healthcare delivery for patient with atrial fibrillation can be improved by advancement in technology that demonstrates cost reduction to the health system and outcomes improvements. Implementation of tactics that decrease cost and improve outcomes can alleviate some of the financial strain on healthcare systems, which is of extreme importance in the current climate.


Subject(s)
Atrial Fibrillation , Catheter Ablation , Cryosurgery , Atrial Fibrillation/therapy , Catheter Ablation/methods , Cryosurgery/adverse effects , Humans , Treatment Outcome
3.
J Cardiovasc Electrophysiol ; 32(2): 183-190, 2021 02.
Article in English | MEDLINE | ID: mdl-33345408

ABSTRACT

BACKGROUND: It is common practice to observe patients during an overnight stay (ONS) following a catheter ablation procedure for the treatment of atrial fibrillation (AF). OBJECTIVES: To investigate the safety and economic impact of a same-day discharge (SDD) protocol after cryoballoon ablation for treatment of AF in high-volume, geographically diverse US hospitals. METHODS: We retrospectively reviewed 2374 consecutive patients (1119 SDD and 1180 ONS) who underwent cryoballoon ablation for AF at three US centers. Baseline characteristics, acute procedure-related complications, and longer-term evaluations of safety were recorded during routine clinical follow-up. The mean cost of an ONS was used in a one-way sensitivity analysis to evaluate yearly cost savings as a function of the percentage of SDD cases per year. RESULTS: The SDD and ONS cohorts were predominately male (69% vs. 67%; p = .3), but SDD patients were younger (64 ± 11 vs. 66 ± 10; p < .0001) with lower body mass index (30 ± 6 vs. 31 ± 61; p < .0001) and CHA2 DS2 -VASc scores (1.4 ± 1.0 vs. 2.2 ± 1.4; p < .0002). There was no difference between SDD and ONS in the 30-day total complication rate (n = 15 [1.26%] versus n = 24 [2.03%]; p = .136, respectively). The most common complication was hematoma in both the SDD (n = 8; 0.67%) and ONS (n = 11; 0.93%) cohorts. Sensitivity analysis demonstrated that when 50% of every 100 patients treated were discharged the same day, hospital cost savings ranged from $45 825 to $83 813 per year across US hospitals. CONCLUSIONS: SDD following cryoballoon ablation for AF appears to be safe and is associated with cost savings across different US hospitals.


Subject(s)
Atrial Fibrillation , Catheter Ablation , Cryosurgery , Pulmonary Veins , Atrial Fibrillation/diagnosis , Atrial Fibrillation/surgery , Cryosurgery/adverse effects , Humans , Male , Patient Discharge , Pulmonary Veins/surgery , Retrospective Studies , Treatment Outcome
4.
Med Pharm Rep ; 93(3): 273-279, 2020 Jul.
Article in English | MEDLINE | ID: mdl-32832892

ABSTRACT

OBJECTIVES: Tobacco use is one of the most critical risk factors for different oral diseases. The aim of this study is to demonstrate the effect of tobacco on oral mucosa by cytomorphometric analysis of cells with the help of exfoliative cytology and to find out the improvement in diagnostic sensitivity of exfoliative cytology in the detection of dysplastic changes and early oral malignancy. METHODS: The nuclear area (NA) and cytoplasmic area (CA) of cells were measured within cytological smear obtained from leukoplakia lesions of buccal mucosa of 90 tobacco users, 30 smokers (TS), 30 chewers (TC) and 30 with combined habit of smoking and chewing (TSC) and from normal buccal mucosa of 30 non users (NU) of tobacco. Each habit group consisted of 30 tobacco users with oral leukoplakia lesion with mild epithelial dysplasia only. The 30 non-users of tobacco served as controls. The mean values of the CA and NA were obtained for each case, and the nuclear/cytoplasmic area (NA/CA) ratio was calculated. RESULTS: The results showed a statistically significant increase (P<0.001) in mean NA and a statistically significant decrease (P<0.001) in mean CA values of tobacco users with leukoplakia as compared to non-users, hence NA/CA ratio value was significantly higher in tobacco users with the lesion. CONCLUSION: The changes in cellular morphology caused by tobacco use can be visualized by use of exfoliative cytology with the help of cytomorphometric analysis. The evaluation of parameters (NA, CA and NA/CA ratio) may increase the sensitivity of exfoliative cytology for the early diagnosis of oral premalignant and malignant lesions.

5.
Acta Crystallogr E Crystallogr Commun ; 74(Pt 9): 1254-1258, 2018 Sep 01.
Article in English | MEDLINE | ID: mdl-30225111

ABSTRACT

The title compound, C16H15N5O2, adopts the shape of the letter L with the dihedral angle between the outer pyridyl rings being 78.37 (5)°; the dihedral angles between the central pyrazolyl ring (r.m.s. deviation = 0.0023 Å) and the methyl-ene-bound pyridyl and methyoxypyridyl rings are 77.68 (5) and 7.84 (10)°, respectively. Intra-molecular amide-N-H⋯N(pyrazol-yl) and pyridyl-C-H⋯O(amide) inter-actions are evident and these preclude the participation of the amide-N-H and O atoms in inter-molecular inter-actions. The most notable feature of the mol-ecular packing is the formation of linear supra-molecular chains aligned along the b-axis direction mediated by weak carbonyl-C=O⋯π(triazol-yl) inter-actions. An analysis of the calculated Hirshfeld surfaces point to the importance of H⋯H (46.4%), C⋯H (22.4%), O⋯H (11.9%) and N⋯H (11.1%) contacts in the crystal.

6.
Clin Pediatr (Phila) ; 51(3): 244-6, 2012 Mar.
Article in English | MEDLINE | ID: mdl-21890838

ABSTRACT

The American Academy of Pediatrics recommends renal ultrasound (RUS) and voiding cystourethrography (VCUG) for all infants after a first urinary tract infection (UTI). However, many congenital renal anomalies are identified by a prenatal US. At the present time, there are no data regarding the yield of post-UTI imaging among infants who have a documented normal prenatal US. We retrospectively reviewed the charts of all patients <1 year of age with a first UTI who had normal kidneys noted on prenatal US to determine the frequency of abnormal findings. Abnormal RUS and VCUG results were noted in 5.1% (24 of 471) and 20.4% (75 of 368) of infants, respectively. While the abnormal US rate is significantly less than what has been previously reported, the frequency of abnormal VCUGs is similar. These results suggest that a post-UTI RUS may not be needed if the prenatal US was normal. However, a VCUG continues to be indicated.


Subject(s)
Hydronephrosis/diagnostic imaging , Kidney/diagnostic imaging , Ultrasonography, Prenatal , Urinary Tract Infections/etiology , Vesico-Ureteral Reflux/diagnostic imaging , Female , Humans , Hydronephrosis/complications , Infant , Infant, Newborn , Kidney/abnormalities , Male , Pregnancy , Radiography , Retrospective Studies , Ureter/abnormalities , Ureter/diagnostic imaging , Urinary Tract Infections/diagnostic imaging , Vesico-Ureteral Reflux/complications
8.
J Clin Invest ; 120(7): 2474-85, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20530870

ABSTRACT

The majority of human skeletal dysplasias are caused by dysregulation of growth plate homeostasis. As TGF-beta signaling is a critical determinant of growth plate homeostasis, skeletal dysplasias are often associated with dysregulation of this pathway. The context-dependent action of TFG-beta signaling is tightly controlled by numerous mechanisms at the extracellular level and downstream of ligand-receptor interactions. However, TGF-beta is synthesized as an inactive precursor that is cleaved to become mature in the Golgi apparatus, and the regulation of this posttranslational intracellular processing and trafficking is much less defined. Here, we report that a cysteine-rich protein, E-selectin ligand-1 (ESL-1), acts as a negative regulator of TGF-beta production by binding TGF-beta precursors in the Golgi apparatus in a cell-autonomous fashion, inhibiting their maturation. Furthermore, ESL-1 inhibited the processing of proTGF-beta by a furin-like protease, leading to reduced secretion of mature TGF-beta by primary mouse chondrocytes and HEK293 cells. In vivo loss of Esl1 in mice led to increased TGF-beta/SMAD signaling in the growth plate that was associated with reduced chondrocyte proliferation and delayed terminal differentiation. Gain-of-function and rescue studies of the Xenopus ESL-1 ortholog in the context of early embryogenesis showed that this regulation of TGF-beta/Nodal signaling was evolutionarily conserved. This study identifies what we believe to be a novel intracellular mechanism for regulating TGF-beta during skeletal development and homeostasis.


Subject(s)
Chondrocytes/metabolism , Growth Plate/metabolism , Homeostasis , Transforming Growth Factor beta/metabolism , Transforming Growth Factor beta/physiology , Animals , Cell Differentiation/physiology , Chondrocytes/cytology , Cytoplasm/metabolism , E-Selectin/metabolism , Furin/metabolism , Growth Plate/cytology , Ligands , Mice , Mice, Knockout , Mice, Transgenic , Receptors, Fibroblast Growth Factor , Selectins/metabolism , Sialoglycoproteins , Signal Transduction/physiology , Xenopus laevis
9.
Int J Dev Biol ; 54(5): 919-24, 2010.
Article in English | MEDLINE | ID: mdl-20336609

ABSTRACT

FoxF genes are essential for visceral mesoderm development from Drosophila to human. However, part of the difficulty of studying the visceral mesoderm is its relative inaccessibility during early development. Owing to its external development Xenopus laevis presents considerable advantages for the study of visceral mesoderm formation, yet FoxF2 has not been identified in this system. Here, we describe the cloning and expression pattern of XFoxF2 during embryonic development, metamorphosis and adulthood, and compare and contrast it to the expression of FoxF1 in Xenopus laevis and FoxF2 in mouse.


Subject(s)
Forkhead Transcription Factors/genetics , Gastrointestinal Tract/metabolism , Gene Expression Profiling , Gene Expression Regulation, Developmental , Xenopus Proteins/genetics , Xenopus laevis/genetics , Amino Acid Sequence , Animals , Base Sequence , Cloning, Molecular , Embryo, Nonmammalian/embryology , Embryo, Nonmammalian/metabolism , Gastrointestinal Tract/embryology , Gastrointestinal Tract/growth & development , In Situ Hybridization , Metamorphosis, Biological/genetics , Molecular Sequence Data , Sequence Homology, Amino Acid , Time Factors , Xenopus laevis/embryology , Xenopus laevis/growth & development
10.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 3): o574, 2010 Feb 10.
Article in English | MEDLINE | ID: mdl-21580341

ABSTRACT

In the title compound, C(18)H(11)BrN(6), the phenyl ring is almost coplanar [dihedral angle 7.2 (1)°] with the planar (r.m.s. deviation 0.039 Å) tricyclic ring system while the 4-bromo-phenyl ring makes a dihedral angle of 33.98 (6)° with the ring system. Weak inter-molecular C-H⋯N and C-H⋯Br hydrogen-bonding inter-actions and π-π stacking [centroid-centroid distances = 3.7971 (17) and 3.5599 (16) Å] stabilize the crystal packing. A comparison of the structure to a MOPAC PM3 geometry optimization calculation in vacuo supports these observations.

11.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 3): o601-2, 2010 Feb 13.
Article in English | MEDLINE | ID: mdl-21580361

ABSTRACT

In the title compound, C(18)H(11)ClN(6), the pyrrole, pyrimidine and tetra-zole rings form a nearly planar fused trihetrocyclic system with an r.m.s. deviation of 0.0387 (13) Å, to which the 4-chloro-phenyl group and the phenyl group are substituted at the 7 and 9 positions, respectively. The dihedral angles between the pyrrole ring and the 4-chloro-phenyl and phenyl rings are 32.1 (4) and 7.87 (7)°, respectively. In the crystal, weak inter-molecular C-H⋯N and C-H⋯Cl hydrogen bonds link the mol-ecules into a layer parallel to the (001) plane. The layers are further connected by π-π stacking inter-actions [centroid-centroid distances: 3.8413 (8) and 3.5352 (8) Å]. Intra-molecular C-H⋯N hydrogen bonds are also present.

12.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 4): o805, 2010 Mar 13.
Article in English | MEDLINE | ID: mdl-21580640

ABSTRACT

In the title compound, C(19)H(14)N(6)O, the fused 12-membered tetra-zolo/pyrimidine/pyrrole ring system is almost planar (r.m.s. deviation = 0.013 Å). The 4-methoxy-phenyl and phenyl substituents on the pyrrole ring are both twisted with respect to the fused-ring system [dihedral angles = 25.39 (18) and 36.42 (18)°, respectively]. Intra-molecular C-H⋯N inter-actions occur. In the crystal, mol-ecules pack into layers in the ac plane and these are connected along the b axis via C-H⋯π and π-π [centroid-centroid separation = 3.608 (3) Å] inter-actions.

13.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 12): o3305, 2010 Nov 27.
Article in English | MEDLINE | ID: mdl-21589583

ABSTRACT

The 12 non-H atoms defining the triple-fused-ring system in the title compound, C(19)H(13)ClN(6), are almost coplanar (r.m.s. deviation = 0.023 Å). The chloro-substituted ring is almost effectively coplanar with the central atoms [dihedral angle = 6.74 (13)°], but the N-bound benzene ring is not [dihedral angle = 54.38 (13)°]. In the crystal, supra-molecular chains along the a axis sustained by C-H⋯π and π-π [centroid-centroid distance between N(4)C and C(4)N five-membered rings = 3.484 (2) Å] stacking occur. A very long C-Cl⋯π contact is also seen.

14.
Dev Dyn ; 238(9): 2193-201, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19334279

ABSTRACT

The transcription factor Pitx3 is critical for lens formation. Deletions in the promoter of this gene cause abnormal lens development in the aphakia (ak) mouse mutant, which has only rudimentary lenses. In this study, we investigated the role of Pitx3 in lens development and differentiation. We found that reduced expression of Pitx3 leads to changes in the proliferation, differentiation and survival of lens cells. The genetic interactions between Pitx3 and Foxe3 were investigated, as these two transcription factors are expressed at the same time in lens development and their absence has similar consequences for lens development. We found no evidence that these two genes genetically interact. In general, our study shows that the abnormal phenotype of the ak lenses is not due to just one molecular pathway, rather in the absence of Pitx3 expression multiple aspects of lens development are disrupted.


Subject(s)
Homeodomain Proteins/physiology , Lens, Crystalline/embryology , Lens, Crystalline/metabolism , Transcription Factors/physiology , Animals , Aphakia/embryology , Aphakia/metabolism , Forkhead Transcription Factors/genetics , Forkhead Transcription Factors/metabolism , Forkhead Transcription Factors/physiology , Homeodomain Proteins/genetics , Homeodomain Proteins/metabolism , Immunohistochemistry , In Situ Hybridization , Mice , Mice, Mutant Strains , Transcription Factors/genetics , Transcription Factors/metabolism
15.
PLoS One ; 4(2): e4513, 2009.
Article in English | MEDLINE | ID: mdl-19229337

ABSTRACT

Rx is a paired-like homeobox gene that is required for vertebrate eye formation. Mice lacking Rx function do not develop eyes or the posterior pituitary. To determine whether Rx is required cell autonomously in these tissues, we generated embryonic chimeras consisting of wild type and Rx-/- cells. We found that in the eye, Rx-deficient cells cannot participate in the formation of the neuroretina, retina pigment epithelium and the distal part of the optic stalk. In addition, in the ventral forebrain, Rx function is required cell autonomously for the formation of the posterior pituitary. Interestingly, Rx-/- and wild type cells segregate before the morphogenesis of these two tissues begins. Our observations suggest that Rx function is not only required for the morphogenesis of the retina and posterior pituitary, but also prior to morphogenesis, for the sorting out of cells to form distinct fields of retinal/pituitary cells.


Subject(s)
Eye Proteins/physiology , Homeodomain Proteins/physiology , Morphogenesis , Pituitary Gland, Posterior/growth & development , Retina/growth & development , Animals , Cell Movement , Chimera , Embryo, Mammalian , Mice , Mice, Knockout , Pituitary Gland, Posterior/embryology , Retina/embryology
16.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 1): o212-3, 2009 Dec 19.
Article in English | MEDLINE | ID: mdl-21580097

ABSTRACT

The title compound, C(20)H(16)N(6)O, is composed of a tetra-zolo ring and a 4-methoxy-phenyl and a benzene-substituted pyrrole ring at the 7 and 9 positions fused to a pyrimidine ring in a nearly planar fashion [maximum deviation of 0.018 (1) Šfor the fused ring system]. A methyl group at the 5 position is also in the plane of the hetero cyclic system. The dihedral angle between the mean planes of the benzene and 4-methoxy-phenyl rings is 40.4 (2)°. The dihedral angles between the mean planes of the pyrimidine and the benzene and 4-methoxy-phenyl rings are 15.6 (5)° and 52.6 (7)°, respectively. A weak intra-molecular C-H⋯N hydrogen bond inter-action, which forms an S(7) graph-set motif, helps to establish the relative conformations of the tetrazolo and benzene rings. In the crystal, weak inter-molecular C-H⋯O, C-H⋯π and π-π stacking inter-actions [centroid-centroid distances = 3.5270 (16), 3.5113 (16), 3.7275 (17) and 3.7866 (17) Å] link the mol-ecules into a two-dimensional array obliquely parallel to (101) and propagating along the b axis.

17.
Int J Dev Biol ; 52(8): 1123-33, 2008.
Article in English | MEDLINE | ID: mdl-18956346

ABSTRACT

The complement system is the central component of innate immunity and an important player in the adaptive immunity of vertebrates. We analyzed the expression patterns of several key members of the complement cascade during Xenopus development. We found extensive expression of these molecules already during gastrula/early neurula stage. Remarkably, several genes also showed an organ-specific expression pattern during early organogenesis. Early expression is notable for two different expression patterns in the neuroectoderm. In one group, there is early strong neural plate and neural precursor expression. This is the case of properdin, C1qA, C3 and C9. The second pattern, seen with C1qR and C6, is noteworthy for its expression at the periphery of the neural plate, in the presumptive neural crest. Two genes stand out for their predominantly mesodermal expression. C3aR, the message for the cognate receptor for C3 in the complement cascade, is expressed at the same time as C3, but in a complementary, reciprocal pattern in the mesoderm. C1qA expression also predominates in somites, pronephros, visceral mesoderm and ventral blood islands. Finally, several genes are characterized by later expression in developing organs. C1qR displays a reticular pattern consistent with expression in the developing vasculature. The late expression of C1qA and C3bC4b is strongest in the pronephros. Finally, the expression of properdin in the hindbrain and in the developing lens are novel findings. The expression patterns of these molecules suggest that these components of the complement system may have in Xenopus a so far undefined developmental role.


Subject(s)
Body Patterning/genetics , Body Patterning/immunology , Complement System Proteins/genetics , Xenopus laevis/embryology , Xenopus laevis/immunology , Animals , Blood Vessels/embryology , Blood Vessels/immunology , Complement C1q/genetics , Complement C3/genetics , Complement C9/genetics , Gene Expression Regulation, Developmental , In Situ Hybridization , Lens, Crystalline/embryology , Lens, Crystalline/immunology , Mesoderm/embryology , Mesoderm/immunology , Neural Tube/embryology , Neural Tube/immunology , Organogenesis/genetics , Organogenesis/immunology , Properdin/genetics , Xenopus Proteins/genetics , Xenopus Proteins/immunology , Xenopus laevis/genetics
18.
Dev Biol ; 322(1): 56-64, 2008 Oct 01.
Article in English | MEDLINE | ID: mdl-18675797

ABSTRACT

Eye development is a complex process that involves the formation of the retina and the lens, collectively called the eyeball, as well as the formation of auxiliary eye structures such as the eyelid, lacrimal gland, cornea and conjunctiva. The developmental requirements for the formation of each individual structure are only partially understood. We have shown previously that the homeobox-containing gene Rx is a key component in eye formation, as retinal structures do not develop and retina-specific gene expression is not observed in Rx-deficient mice. In addition, Rx-/- embryos do not develop any lens structure, despite the fact that Rx is not expressed in the lens. This demonstrates that during normal mammalian development, retina-specific gene expression is necessary for lens formation. In this paper we show that lens formation can be restored in Rx-deficient embryos experimentally, by the elimination of beta-catenin expression in the head surface ectoderm. This suggests that beta-catenin is involved in lens specification either through Wnt signaling or through its function in cell adhesion. In contrast to lens formation, we demonstrate that the development of auxiliary eye structures does not depend on retina-specific gene expression or retinal morphogenesis. These results point to the existence of two separate developmental processes involved in the formation of the eye and its associated structures. One involved in the formation of the eyeball and the second involved in the formation of the auxiliary eye structures.


Subject(s)
Eye Proteins/physiology , Eye/embryology , Homeodomain Proteins/physiology , Retina/embryology , beta Catenin/physiology , Animals , Conjunctiva/cytology , Conjunctiva/embryology , Eye/cytology , Eye Proteins/genetics , Eyelids/cytology , Eyelids/embryology , Gene Expression Regulation, Developmental , Genes, Reporter , Homeodomain Proteins/genetics , In Situ Hybridization , Lacrimal Apparatus/cytology , Lacrimal Apparatus/embryology , Lens, Crystalline/cytology , Lens, Crystalline/embryology , Mice , Mice, Knockout , Retina/cytology , beta Catenin/genetics
19.
J Biol Chem ; 283(32): 22157-65, 2008 Aug 08.
Article in English | MEDLINE | ID: mdl-18508765

ABSTRACT

Myocardial infarction (MI) is often followed by heart failure (HF), but the mechanisms precipitating the transition to HF remain largely unknown. A genomic profile was performed in a monkey model of MI, from the myocardium adjacent to chronic (2-month) MI followed by 3 weeks of pacing to develop HF. The transcript of the gene encoding the cell cycle-related kinase (CCRK) was down-regulated by 50% in HF heart compared with control (p<0.05), which was confirmed by quantitative PCR. The CCRK sequence cloned from a heart library showed a conservation of the N-terminal kinase domain when compared with the "generic" isoform cloned previously but a different C-terminal half due to alternative splicing with frameshift. The homology of the cardiac sequence was 100% between mice and humans. Expression of the corresponding protein, measured upon generation of a monoclonal antibody, was limited to heart, liver, and kidney. Upon overexpression in cardiac myocytes, both isoforms promote cell growth and reduce apoptosis by chelerythrine (p<0.05 versus control). Using a yeast two-hybrid screening, we found an interaction of the generic but not the cardiac CCRK with cyclin H and casein kinase 2. In addition, only the generic CCRK phosphorylates the cyclin-dependent kinase 2, which was accompanied by a doubling of myocytes in the S and G(2) phases of the cell cycle (p < 0.05 versus control). Therefore, the heart expresses a splice variant of CCRK, which promotes cardiac cell growth and survival; differs from the generic isoform in terms of protein-protein interactions, substrate specificity and regulation of the cell cycle; and is down-regulated significantly in HF.


Subject(s)
Cyclin-Dependent Kinases/metabolism , Heart Failure/enzymology , Myocardium/enzymology , Amino Acid Sequence , Animals , Base Sequence , Cell Proliferation , Cell Survival , Cells, Cultured , Cloning, Molecular , Cyclin-Dependent Kinases/chemistry , Cyclin-Dependent Kinases/genetics , Disease Models, Animal , Isoenzymes/chemistry , Isoenzymes/genetics , Isoenzymes/metabolism , Macaca fascicularis , Male , Mice , Molecular Sequence Data , Protein Binding , Rats , Rats, Wistar , Sequence Alignment , Substrate Specificity
20.
Genesis ; 46(3): 177-83, 2008 Mar.
Article in English | MEDLINE | ID: mdl-18327772

ABSTRACT

In this article, we investigate the expression, regulation, and function of the zebrafish forkhead gene foxe3. In wild type embryos, foxe3 is first expressed in a crescent-shaped area at the anterior end of the prechordal plate, corresponding to the polster. At later stages, the hatching gland, the lens, and the anterior pituitary express this gene. Using morpholinos against the zinc finger Kruppel-like factor 4 (KLF4) we show that foxe3 is regulated differently in the polster and in the lens. In the absence of KLF4, expression of foxe3 in the polster is not activated, whereas in the lens placode the expression of KLF4 is not required for the transcription of foxe3. The expression of foxe3 is also regulated by the hedgehog and nodal signaling pathways. foxe3 expression is altered in the hedgehog pathway mutants iguana and you-too and the nodal pathway mutant cyclops. foxe3 function is necessary for the execution of lens-specific gene expression and lens morphogenesis, as the knockdown of foxe3 results in a loss of platelet-derived growth factor receptor alpha (pdgfralpha) expression and in the vacuolization of the lens.


Subject(s)
Eye Proteins/genetics , Eye Proteins/physiology , Forkhead Transcription Factors/genetics , Forkhead Transcription Factors/physiology , Zebrafish Proteins/genetics , Zebrafish Proteins/physiology , Zebrafish/embryology , Zebrafish/genetics , Animals , Animals, Genetically Modified , Carrier Proteins/genetics , Carrier Proteins/metabolism , Embryo, Nonmammalian , Eye Proteins/metabolism , Forkhead Transcription Factors/metabolism , Gene Expression Regulation, Developmental , Lens, Crystalline/embryology , Lens, Crystalline/metabolism , Morphogenesis/genetics , Mutant Proteins/metabolism , Receptor, Platelet-Derived Growth Factor alpha/genetics , Receptor, Platelet-Derived Growth Factor alpha/metabolism , Time Factors , Transcription Factors/genetics , Transcription Factors/metabolism , Zebrafish Proteins/metabolism , Zinc Finger Protein Gli2
SELECTION OF CITATIONS
SEARCH DETAIL
...