Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Notch”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,711 records · Page 95Linked to original sources
PubMed1990

Terminal notching of the QRS complex in V1 and V2 in seborrheic patients.

Widening of the QRS complex by terminal notching in leads V1 and V2 was observed in 6 seborrheic patients with adequate personal hygiene. This anomaly disappeared when the presternal skin was degreased thoroughly with cationic detergent before placing the conductive paste and electrodes. We attribute these electrocardiographic alterations to variations in the apocrine secretions in the presternal region, which modified the resistance of the skin to electrical potentials.

Acne Vulgaris↗
PubMed1995

Computer analysis of the early diastolic notch in Doppler sonograms of the uterine arteries.

This article describes a set of processing and analysis techniques for automated identification and quantification of the early diastolic notch (EDN), a feature of Doppler sonograms from the uterine arteries which has been associated with adverse pregnancy outcomes such as preeclampsia and intrauterine growth retardation. Examples covering different sonogram types are provided to illustrate the effectiveness and reproducibility of the processing/analysis tools. Also, a receiver-operating characteristic-based evaluation of the EDN quantification and pulsatility indexes is presented, which examines the ability to predict hypertension and/or intrauterine growth retardation, using a set of uterine Doppler sonograms from 92 patients acquired at 18 weeks of gestation. In summary, the ROC results confirm the link between the EDN and abnormal pregnancy outcomes, and suggest that EDN quantification has a higher diagnostic accuracy than the pulsatility index, which characterises the flow waveform in a global manner and therefore does not take explicitly into account the localised nature of the EDN. Quantification of the EDN at 18 weeks of gestation appears to best predict the most severely abnormal pregnancy outcomes.

Arteries↗
PubMed1996

"Crochetage" (notch) on R wave in inferior limb leads: a new independent electrocardiographic sign of atrial septal defect.

OBJECTIVES: This study sought to determine the clinical significance of a "crochetage" pattern--a notch near the apex of the R wave in electrocardiographic (ECG) inferior limb leads--in secundum atrial septal defect. BACKGROUND: Atrial septal defect is often overdiagnosed on the basis of classical clinical features. Thus, more specific signs on the ECG for screening are needed. Methods. We searched for a crochetage pattern in 1,560 older children and adults: 532 with secundum atrial septal defect, 266 with ventricular septal defect, 146 with pulmonary stenosis, 110 with mitral stenosis, 47 with cor pulmonale and 459 normal subjects. RESULTS: This pattern was observed respectively in 73.1%, 35.7%, 23.3%, 6.4%, 10.6% and 7.4% of these groups (p<0.001). In atrial septal defect, its incidence increased with larger anatomic defect (p<0.0001) or greater left-to-right shunt (p<0.0001), even in the presence of pulmonary hypertension. By multiple regression analysis, only shunt size (p<0.0006) and defect location (p<0.0001) were the determinants of its presence. In all groups, the specificity of this sign for the diagnosis was remarkably high when present in all three inferior limb leads (> or = to 92%), even when comparison was limited to patients with an incomplete right bundle branch block (> or = 95.2%). Early disappearance of this pattern was observed in 35.1% of the operated-on patients although the right bundle branch block pattern persisted. CONCLUSIONS: A crochetage pattern of the R wave in inferior limb leads is frequent in patients with atrial septal defect, correlates with shunt severity and is independent of the right bundle branch block pattern. Sensitivity and specificity of this sign are remarkably high when it is associated with an incomplete right bundle branch block or present in all inferior limb leads.

Adolescent↗
PubMed2004

Deltoid (triangular)-shaped anterior cruciate ligament that caused notch impingement: a report of two cases.

In this article, we present 2 previously unreported cases of anterior cruciate ligaments (ACL) that had a wide deltoid (triangular)-shaped tibial insertion in the coronal plane that caused impingement at the intercondylar notch, inferior parts of patellofemoral sulcus, and the posterior cruciate ligament (PCL). Ligamentoplasty was used in both cases. Inferomedial and inferolateral parts of the ACL that caused impingement were excised, and the normal width of the tibial insertion of the ACL was provided.

Adult↗
PubMed2006

A mouse homologue of Strawberry Notch is transcriptionally regulated by Reelin signal.

Reelin is a glycoprotein secreted by specific neuronal populations of the adult and developing nervous system of vertebrates. The morphological abnormalities in the brain of reeler, the Reelin deficient mutant mice, indicate that Reelin is essential for the brain morphogenesis. However, biochemical function of Reelin signal is not well understood. Here, we examined possible function of Reelin signal in regulation of gene expression by performing a microarray analysis. We found that expression level of a mouse homologue of Strawberry Notch (mSno1) is markedly reduced in the reeler embryos. In situ hybridization showed that mSno1 is expressed in the developing nervous system colocalizing with expression of ApoER2, a Reelin receptor. Treatment of P19 cells with Reelin protein enhanced mSno1 expression. Overexpression of ApoER2 with Reelin treatment gave a synergistic effect on mSno1 expression level. These observations suggest that Reelin signal is involved in embryonic expression of a novel vertebrate gene, mSno1.

Animals↗
PubMed2005

Phox2B mutations and the Delta-Notch pathway in neuroblastoma.

We recently identified six neuroblastoma patients with constitutional or tumor-specific mutations in the homeobox gene Phox2B. Phox2B controls part of the differentiation program of the sympathetic nervous system (SNS). Mice with a homozygous inactivation of Phox2B fail in the proper differentiation of the chromaffin lineage of the SNS. Phox2B regulates HASH1 which can control expression of genes of the Delta-Notch pathway. We previously showed that a subset of neuroblastoma cell lines highly expresses Delta-like 1 (Dlk1), which is a marker for the chromaffin lineage of the SNS. Notch3 is expressed in another subset of neuroblastoma cell lines and marks tumors from an alternative differentiation lineage. Phox2B is also related to the TrkA differentiation pathway in neuroblastoma. Here we will review the role of Phox2B in differentiation programs of the SNS and in neuroblastoma pathogenesis.

Animals↗
PubMed2006

Adverse outcome in women with thrombophilia and bilateral uterine artery notches.

Discrepancies about a possible relationship between prothrombotic mutations and a decreased uteroplacental blood flow are present in literature. We prospectively evaluated a cohort of pregnant women (n = 41) with bilateral uterine artery notches and found that women with inherited thrombophilia showed a sixfold higher risk to have an adverse outcome than women without.

Adult↗
PubMed2005

Distal radioulnar joint instability in distal radius fractures: the role of sigmoid notch and triangular fibrocartilage complex revisited.

The stabilising effects of various structures of the distal radioulnar joint (DRUJ) have been heavily debated. This biomechanical cadaveric study examined the effects of the volar and dorsal lips of the sigmoid notch and the volar and dorsal aspects of the triangular fibrocartilage complex (TFCC) on DRUJ stability. Sequential fractures of the distal radius and sectioning of the TFCC were performed followed by measurements of ulnar translation with the forearm in pronation, neutral and supination. A dorsal lunate facet fracture created instability in pronation. Lunate facet fractures alone did not create instability in other forearm positions. Sectioning of the volar TFCC after loss of the dorsal TFCC by a dorsal lunate facet fracture caused DRUJ instability with the forearm in neutral position. Sectioning of the dorsal TFCC after loss of the volar TFCC due to a volar lunate facet fracture created instability in neutral and pronated positions.

Biomechanical Phenomena↗
PubMed2006

Fracture toughness of manatee rib and bovine femur using a chevron-notched beam test.

Bone is an anisotropic material with a hierarchical structure consisting of organic matrix, minerals and water. Fracture toughness (K(C)) has been shown to be a good index to assess the mechanical performance of bone. A chevron-notched (CN) beam test, a standard fracture mechanics test successfully applied to many other materials, was used to determine the transverse-direction fracture toughness in manatee rib and bovine femur cortical bone. Although human and bovine bone has been well studied, there is virtually no information on the toughness of manatee rib bone. As a biological material, manatee rib is interesting for study in that it is a highly mineralized bone. Three major advantages of the CN specimen test are: (1) it is easier to reach plane strain condition; (2) there is no fatigue-precracking needed; and (3) it is relatively easy to produce stable crack propagation before catastrophic fracture. The fracture toughness values of manatee rib and bovine femur were measured to be 4.5 +/- 0.5 MPa m(1/2) and 5.8 +/- 0.5 MPa m(1/2), respectively. Based on the microstructures shown in SEM images, two features that contributed to the greater fracture toughness of bovine femur were identified as greater osteon density and lesser porosity.

Animals↗
PubMedDate not supplied

[Neglected fracture-dislocation of the elbow: surgical reduction with enlarging osteoplasty of the trochlear notch. Case report].

Elbow dislocations in the infant are not very frequent and are associated to the fractures. Their management must be urgent and rigorous if complications are to be avoided. We report the case of a child aged 12 who presented with a fracture-dislocation of the right elbow, after falling from a tree. The patient was treated in a standard manner for one month. Four months later, the patient presented again, this time complaining of stiffness of the elbow. Physical examination confirmed the reduced range of movement of the elbow (flexion 80 degrees, extension -30 degrees) without associated neurovascular complication. Radiography of the elbow showed a posterior dislocation with remodelling of the humeral contours. Surgical exploration revealed normal articular cartilage, a pseudoarthrosis of the epitrochlea, a dislocation of the radial head and the sigmoid fossa of small size in relation to the trochlea. A reduction was only possible after an "enlargement plasty" of the trochlear notch. The patient was seen after an interval of six months. The elbow was stable with no vasculo-nervous complication.and had flexion of 110 degrees with extension of -30 degrees.

Child↗
PubMed2006

Notch signaling plays a key role in cardiac cell differentiation.

Results from lineage tracing studies indicate that precursor cells in the ventricles give rise to both cardiac muscle and conduction cells. Cardiac conduction cells are specialized cells responsible for orchestrating the rhythmic contractions of the heart. Here, we show that Notch signaling plays an important role in the differentiation of cardiac muscle and conduction cell lineages in the ventricles. Notch1 expression coincides with a conduction marker, HNK-1, at early stages. Misexpression of constitutively active Notch1 (NIC) in early heart tubes in chick exhibited multiple effects on cardiac cell differentiation. Cells expressing NIC had a significant decrease in expression of cardiac muscle markers, but an increase in expression of conduction cell markers, HNK-1, and SNAP-25. However, the expression of the conduction marker connexin 40 was inhibited. Loss-of-function study, using a dominant-negative form of Suppressor-of-Hairless, further supports that Notch1 signaling is important for the differentiation of these cardiac cell types. Functional studies show that the expression of constitutively active Notch1 resulted in abnormalities in ventricular conduction pathway patterns.

Animals↗
PubMed2005

Hesr, a mediator of the Notch signaling, functions in heart and vessel development.

Hesr genes are members of the hairy and enhancer of split-related (hesr) gene family of basic helix-loop-helix-type transcriptional repressors. hesr genes have been implicated in cardiovascular development as the primary targets of Notch signaling. Functional analysis of hesr2 knockout mice revealed abnormal cardiac hemodynamics, such as atrioventricular valve regurgitation and reduced left ventricular systolic function, caused by hypoplastic AV valves and abnormal cardiomyocytes. Recent evidence demonstrates that hesr1 and hesr2 function redundantly in epithelial-to-mesenchymal transformation during atrioventricular valve formation and maintenance of trabecular cells in the heart ventricles, and in arterial-venous differentiation of blood vessels. This review highlights the many functions of the hesr gene family in heart and vessel development.

Animals↗
PubMed1997

Kernohan-Woltman notch phenomenon: an unusual cause of ipsilateral motor deficit.

Posttraumatic ipsilateral motor deficits are rare and raise etiologic and prognostic concerns for the rehabilitation team. We present two cases with an unusual central neurologic cause of ipsilateral weakness. The first patient was assaulted, with a resultant severe traumatic brain injury. Initial computed tomography showed a large right subdural hematoma (SDH) with significant mass effect. Following a craniotomy for evacuation of the SDH, the patient was noted to have paradoxical right-sided (ipsilateral) motor deficits. Postoperative magnetic resonance imaging (MRI) showed compression of the contralateral (left) cerebral peduncle against the tentorium, thus resulting in ipsilateral (right-sided) motor weakness (the Kernohan-Woltman notch phenomenon). Prior limited reports carried a grave prognosis for these patients. On discharge from inpatient rehabilitation, the patient was functioning at a Rancho Los Amigos Scale VI. The second patient was involved in a motor vehicle accident and was found to have a large left frontotemporal subdural hematoma with shift. A dense left hemiplegia was noted after hematoma evacuation. MRI also showed a right cerebral peduncle hypointensity. At discharge, the patient was rated a Rancho Los Amigos Scale VI. Physiatrists need to be aware of the causes of ipsilateral motor weakness as well as the limitations of prognostic data.

Adolescent↗
PubMed1980

The supinator notch sign in rheumatoid arthritis.

Erosion of the ulna, giving a notch-like appearance in the region of the supinator groove, is reported in 18% of 110 unselected outpatients attending a rheumatoid clinic. The characteristic radiological, arthrographic and scintigraphic findings are presented. The mechanism, significance and differential diagnosis is discussed.

Aged↗
PubMed2002

Carhart's notch: a finding in otitis media with effusion.

INTRODUCTION: Carhart's notch (CN) is a false depression of bone conduction (BC) thresholds at 2-4 kHz initially described in cases of stapes fixation. This study was designed to estimate the incidence and assess the clinical significance of CN in cases of otitis media with effusion (OME) in children. PATIENTS AND METHODS: Clinical records of 50 patients of OME that showed CN were analysed, retrospectively. First 24 were identified as seen in outpatients and 26 were found out of 100 consecutive cases of OME. The criteria of CN were a minimum 10 dB depression in BC at any frequency 500-4000 Hz. RESULTS: Fifty patients showed CN, with mean age of 8.8 years. All had myringotomies with or without insertion of grommets. The CN ranged from 10 to 20 dB in the majority and up to 30 dB in few cases. In 85 ears studied, the affected frequencies comprised of 2000 Hz in 80 (94%), 4000 Hz in 4 and 1000 Hz in one ear. Pre-operative tympanograms were of type B in 68 (80%), type C in 16 (18.8%) and type A in one ear. Middle ear fluid was thick glue in 57 (67%), serous in 5 (5.8%), and no fluid found in 23 (27%) cases. Oedematous, granular or polypoidal appearances of middle ear mucosa were noted in 57 (67%) of the ears. A normal mucosa was seen in 17 (20%), and no details were available in 11 (13%) ears. Post-operative audiograms showed improvements of BC thresholds in 72 (84.7%) of the ears. CONCLUSION: Our results show 26% incidence of CN in paediatric cases of OME, with evidence of thick fluid and abnormal middle ear mucosa in about two-thirds of cases. This suggests that CN may be of prognostic value for myringotomy outcomes. Statistically there is a significant correlation between presence of fluid on myringotomy and CN, and type of tympanogram and post-operative BC threshold improvement. There is no predictive value of CN in terms of character of the middle ear fluid. Studies with larger numbers may be required to determine this with more certainty. It can help clinically, however, in pre-operative assessment of these cases. It is our opinion that BC should be an essential part of routine audiometry in all cases of OME.

Audiometry, Pure-Tone↗
PubMed1999

The Alzheimer-related gene presenilin 1 facilitates notch 1 in primary mammalian neurons.

The normal functional neurobiology of the Alzheimer's disease (AD) related gene presenilin 1 (PS1) is unknown. One clue comes from a genetic screen of Caenorhabditis elegans, which reveals that the presenilin homologue sel-12 facilitates lin-12 function [D. Levitan, I. Greenwald, Facilitation of lin-12-mediated signalling by sel-12, a Caenorhabditis elegans S182 Alzheimer's disease gene, Nature 377 (1995) 351-355]. The mammalian homologue of lin-12, Notch1, is a transmembrane receptor that plays an important role in cell fate decisions during development, including neurogenesis, but does not have a known function in fully differentiated cells. To better understand the potential role of Notch1 in mammalian postmitotic neurons and to test the hypothesis that Notch and PS 1 interact, we studied the effect of Notch1 transfection on neurite outgrowth in primary cultures of hippocampal/cortical neurons. We demonstrate that Notch1 inhibits neurite extension, and thus has a function in postmitotic mature neurons in the mammalian CNS. Furthermore, we present evidence demonstrating that there is a functional interaction between PS1 and Notch1 in mammalian neurons, analogous to the sel-12/lin-12 interaction in vulval development in C. elegans [D. Levitan, T. Doyle, D. Brousseau, M. Lee, G. Thinakaran, H. Slunt, S. Sisodia, I. Greenwald, Assessment of normal and mutant human presenilin function in Caenorhabditis elegans, Proc. Natl. Acad. Sci. U.S.A. 93 (1996) 14940-14944; D. Levitan, I. Greenwald, Effect of Sel-12 presenilin on Lin-12 localization and function in Caenorhabditis elegans, Development, 125 (1998) 3599-3606]. The inhibitory effect of Notch1 on neurite outgrowth is markedly attenuated in neurons from PS1 knockout mice, and enhanced in neurons from transgenic mice overexpressing wild type PS1, but not mutant PS1. These data suggest that PS1 facilitates Notch1 function in mammalian neurons, and support the hypothesis that a functional interaction exists between PS1 and Notch1 in postmitotic mammalian neurons.

Alzheimer Disease↗
PubMed1999

Magnetic resonance imaging findings of Kernohan-Woltman notch in acute subdural hematoma.

OBJECTIVE AND IMPORTANCE: We report the case of a 73-year-old patient who presented a right motor deficit caused by an ipsilateral acute subdural hematoma. A magnetic resonance imaging (MRI) demonstration of Kernohan-Woltman notch phenomenon was obtained. CLINICAL PRESENTATION: The woman sustained a major head injury at home, followed by loss of consciousness. On admission to the emergency room, she was comatose, anisochoric (left > right), and showed a reaction to pain with decerebrating movements of left limbs (Glasgow Coma Scale (GCS) 4/15). A right severe hemiparesis was observed. Cerebral computed tomography scan showed a large right hemispheric subdural hematoma. INTERVENTION AND POST-OPERATIVE COURSE: A wide right craniotomy was performed and the subdural hematoma evacuated. During the post-operative period, the level of consciousness gradually improved. A MRI performed about 2 weeks after operation showed a small area of abnormal signal intensity in the left cerebral peduncle. On discharge, the woman was able to communicate with others, but her right hemiparesis was still severe.

Aged↗