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1.
AJNR Am J Neuroradiol ; 41(2): 293-299, 2020 02.
Article in English | MEDLINE | ID: mdl-31879333

ABSTRACT

Reversible vasoconstriction syndrome is a complex of clinical symptoms and angiographic findings, which, while having a mostly benign clinical course, has clinical and imaging overlap with more serious disorders such as vasculitis and aneurysmal SAH and itself includes a minority of patients with fulminant vasoconstriction resulting in severe intracranial complications. Endovascular options for patients with refractory reversible cerebral vasoconstriction syndrome include intra-arterial vasodilator infusion similar to therapy for patients with vasospasm after SAH. To date, only case reports and 1 small series have discussed the utility of intra-arterial vasodilators for the treatment of reversible cerebral vasoconstriction syndrome. We report an additional series of 11 medically refractory cases of presumed or proved reversible cerebral vasoconstriction syndrome successfully treated with intra-arterial verapamil infusion. Furthermore, we propose that the reversal of vasoconstriction, as seen on angiography, could fulfill a diagnostic criterion.


Subject(s)
Cerebrovascular Disorders/drug therapy , Vasoconstriction/drug effects , Vasodilator Agents/administration & dosage , Vasospasm, Intracranial/drug therapy , Verapamil/administration & dosage , Adult , Aged , Female , Humans , Infusions, Intra-Arterial , Male , Middle Aged
3.
J Neurointerv Surg ; 4(2): 87-93, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22278933

ABSTRACT

OBJECTIVE: To summarize and classify the evidence for the use of endovascular techniques in the treatment of patients with acute ischemic stroke. METHODS: Recommendations previously published by the American Heart Association (AHA) (Guidelines for the early management of adults with ischemic stroke (Circulation 2007) and Scientific statement indications for the performance of intracranial endovascular neurointerventional procedures (Circulation 2009)) were vetted and used as a foundation for the current process. Building on this foundation, a critical review of the literature was performed to evaluate evidence supporting the endovascular treatment of acute ischemic stroke. The assessment was based on guidelines for evidence based medicine proposed by the Stroke Council of the AHA and the University of Oxford, Centre for Evidence Based Medicine (CEBM). Procedural safety, technical efficacy and impact on patient outcomes were specifically examined.


Subject(s)
Brain Ischemia/therapy , Endovascular Procedures/standards , Stroke/therapy , Thrombolytic Therapy/standards , American Heart Association , Brain Ischemia/drug therapy , Brain Ischemia/surgery , Cerebral Angiography , Combined Modality Therapy , Endovascular Procedures/classification , Endovascular Procedures/instrumentation , Fibrinolytic Agents/therapeutic use , Humans , Practice Guidelines as Topic , Research Report , Societies, Medical/standards , Stroke/drug therapy , Stroke/surgery , Thrombolytic Therapy/classification , United States
4.
AJNR Am J Neuroradiol ; 31(1): E8-11, 2010 01.
Article in English | MEDLINE | ID: mdl-20075105

ABSTRACT

Stroke is the third leading cause of death in the USA, Canada, Europe, and Japan. According to the American Heart Association and the American Stroke Association, there are now 750,000 new strokes that occur each year, resulting in 200,000 deaths, or 1 of every 16 deaths, per year in the USA alone. Endovascular therapy for patients with acute ischemic stroke is an area of intense investigation. The American Stroke Association has given a qualified endorsement of intra-arterial thrombolysis in selected patients. Intra-arterial thrombolysis has been studied in two randomized trials and numerous case series. Although two devices have been granted FDA approval with an indication for mechanical stroke thrombectomy, none of these thrombectomy devices has demonstrated efficacy for the improvement of patient outcomes. The purpose of the present document is to define what constitutes adequate training to perform neuroendovascular procedures in patients with acute ischemic stroke and what performance standards should be adopted to assess outcomes. These guidelines have been written and approved by multiple neuroscience societies which historically have been directly involved in the medical, surgical and endovascular care of patients with acute stroke. The participating member organizations of the Neurovascular Coalition involved in the writing and endorsement of this document are the Society of NeuroInterventional Surgery, the American Academy of Neurology, the American Association of Neurological Surgeons/Congress of Neurological Surgeons Cerebrovascular Section, and the Society of Vascular & Interventional Neurology.

5.
J Neurointerv Surg ; 1(1): 10-2, 2009 Jul.
Article in English | MEDLINE | ID: mdl-21994099

ABSTRACT

Stroke is the third leading cause of death in the USA, Canada, Europe, and Japan. According to the American Heart Association and the American Stroke Association, there are now 750,000 new strokes that occur each year, resulting in 200,000 deaths, or 1 of every 16 deaths, per year in the USA alone. Endovascular therapy for patients with acute ischemic stroke is an area of intense investigation. The American Stroke Association has given a qualified endorsement of intra-arterial thrombolysis in selected patients. Intra-arterial thrombolysis has been studied in two randomized trials and numerous case series. Although two devices have been granted FDA approval with an indication for mechanical stroke thrombectomy, none of these thrombectomy devices has demonstrated efficacy for the improvement of patient outcomes. The purpose of the present document is to define what constitutes adequate training to perform neuroendovascular procedures in patients with acute ischemic stroke and what performance standards should be adopted to assess outcomes. These guidelines have been written and approved by multiple neuroscience societies which historically have been directly involved in the medical, surgical and endovascular care of patients with acute stroke. The participating member organizations of the Neurovascular Coalition involved in the writing and endorsement of this document are the Society of NeuroInterventional Surgery, the American Academy of Neurology, the American Association of Neurological Surgeons/Congress of Neurological Surgeons Cerebrovascular Section, and the Society of Vascular & Interventional Neurology.


Subject(s)
Brain Ischemia/therapy , Cerebral Revascularization/education , Cerebral Revascularization/standards , Neurosurgery/education , Neurosurgery/standards , Stroke/therapy , Accreditation/standards , Acute Disease , Humans
6.
Neuroradiology ; 47(1): 62-5, 2005 Jan.
Article in English | MEDLINE | ID: mdl-15633053

ABSTRACT

Isolated arteriovenous fistulas of the posterior orbit occur with exceptional rarity, and their evaluation and management are not well characterized. We describe the clinical presentation and treatment of a spontaneous arteriovenous fistula of the right posterior orbit via a superior ophthalmic vein approach for embolization using platinum detachable coils.


Subject(s)
Arteriovenous Fistula/therapy , Embolization, Therapeutic/instrumentation , Orbit/blood supply , Adult , Angiography, Digital Subtraction , Arteriovenous Fistula/diagnosis , Cavernous Sinus/pathology , Equipment Design , Follow-Up Studies , Humans , Magnetic Resonance Angiography , Male , Maxillary Artery/pathology , Ophthalmic Artery/pathology , Platinum , Veins
7.
Acad Radiol ; 5(3): 224-31, 1998 Mar.
Article in English | MEDLINE | ID: mdl-9522890

ABSTRACT

RATIONALE AND OBJECTIVES: The American Association of Academic Chief Residents in Radiology annually surveys residency programs on a variety of issues related to residency training. The survey results allow individual programs to compare features of their programs with national averages and to gauge trends in radiology residency training. MATERIALS AND METHODS: Questionnaires were mailed to the chief residents in 180 accredited radiology residency programs in the United States. A variety of demographic and common-interest questions were asked. The 1997 survey focused on American Board of Radiology (ABR) examination preparation, residency curriculum, and socioeconomic issues relevant to graduating radiology residents. RESULTS: Completed surveys from 73 programs (41%) were returned. Areas of curriculum concern among chief residents reflected primarily current turf issues. A higher than expected percentage of residents considered their training to be inadequate in nonneurologic magnetic resonance imaging and chest, musculoskeletal, and genitourinary radiology. Job security is a major emerging concern for radiology residents who are considering careers in private practice. The practice of remembering and transcribing questions from the ABR written examination is common, and these questions are a valued resource in preparing for the diagnostic section of the written examination. Most residents attend a commercial review course before the oral examination, and the majority of programs also provide internal review courses. CONCLUSION: A higher than expected percentage of chief residents expressed concern regarding training in subspecialties of radiology that are neither areas of turf dispute nor areas where certificate of additional qualification examinations are offered. Radiology programs and residents expend substantial resources on preparation for the ABR examinations in addition to the usual 4-year curriculum. The most valued resource for the diagnostic section of the examination is almost certainly not equally available. Radiology residents are increasingly concerned about future job security.


Subject(s)
Internship and Residency , Radiology/education , Attitude of Health Personnel , Data Collection , Employment , Humans , Salaries and Fringe Benefits , United States
8.
J Struct Biol ; 116(2): 264-9, 1996.
Article in English | MEDLINE | ID: mdl-8812982

ABSTRACT

We describe the helical structure of Bordetella pertussis fimbriae of serotype 3/6 as determined to a resolution of approximately 2.5 nm by three-dimensional reconstruction of negatively stained electron micrographs. The fimbria has a distinctly polar structure whose axial repeat of 13 nm contains five copies of the fim3 gene product (22 kDa) in two complete turns. These subunits are connected by interactions along the fimbrial backbone which, unlike other classes of bacterial fimbriae, has no axial channel. Its outer diameter is approximately 5.7 nm, and the most pronounced feature is a radially protruding domain that gives the fimbria its characteristic serrated appearance. Serotype 2 fimbriae, composed of the fim2 subunit which is 60% homologous with fim3, have essentially the same quaternary structure. These observations are discussed in relation to fimbrial phase variation and structure-based classification of fimbriae/pili.


Subject(s)
Antigens, Bacterial , Bordetella pertussis/ultrastructure , Fimbriae Proteins , Fimbriae, Bacterial/ultrastructure , Image Processing, Computer-Assisted/methods , Virulence Factors, Bordetella , Bacterial Proteins/chemistry , Bacterial Proteins/genetics , Bacterial Proteins/ultrastructure , Bordetella pertussis/genetics , Fimbriae, Bacterial/chemistry , Fimbriae, Bacterial/genetics , Microscopy, Electron , Negative Staining , Protein Conformation
9.
J Virol ; 67(4): 2402-7, 1993 Apr.
Article in English | MEDLINE | ID: mdl-8445736

ABSTRACT

The ability of the high-risk and low-risk human papillomavirus E7 oncoproteins to disrupt complexes of the retinoblastoma tumor suppressor protein pRB and the cellular transcription factor E2F was studied. The ability of E7 to disrupt this transcription factor complex correlated with the different pRB binding efficiencies of the high-risk and low-risk human papillomavirus-encoded E7 proteins. The pRB binding site was the sole determinant for these observed differences. The phosphorylation status of the casein kinase II site that is immediately adjacent to the pRB binding site in E7 had no marked effect on this biochemical property of E7. Peptides consisting of the pRB binding site of E7, however, were not able to disrupt the pRB/E2F complex. These data suggest that additional carboxy-terminal sequences in E7 are also required for the efficient disruption of the pRB/E2F complex and that E7 and E2F may interact with nonidentical sites of pRB.


Subject(s)
Carrier Proteins , Cell Cycle Proteins , DNA-Binding Proteins/metabolism , Neoplasm Proteins , Oncogene Proteins, Viral/metabolism , Retinoblastoma Protein/metabolism , Transcription Factors/metabolism , Base Sequence , Binding Sites , E2F Transcription Factors , In Vitro Techniques , Macromolecular Substances , Molecular Sequence Data , Oligodeoxyribonucleotides/chemistry , Oncogene Proteins, Viral/chemistry , Papillomavirus E7 Proteins , Protein Binding , Recombinant Fusion Proteins/metabolism , Retinoblastoma-Binding Protein 1 , Transcription Factor DP1
10.
Proc Natl Acad Sci U S A ; 89(10): 4442-6, 1992 May 15.
Article in English | MEDLINE | ID: mdl-1316608

ABSTRACT

The human papillomaviruses (HPVs) associated with genital tract lesions can be classified as either "high risk" or "low risk" based on their association with human anogenital cancer. The E7 proteins of the high-risk and the low-risk viruses are quite similar in their amino acid composition and structural organization yet differ in their transforming potential and in a number of biochemical properties. A series of chimeric proteins consisting of segments of the high-risk HPV-16 and the low-risk HPV-6 E7 proteins were constructed in order to define which domains within the amino-terminal half of E7 were responsible for the different biological and biochemical properties. The E7 oncogenic capacity, which was determined by assaying transformation of baby rat kidney cells in cooperation with an activated ras oncogene, segregated with the retinoblastoma tumor suppressor protein (pRB) binding domain of the HPV-16 E7 protein. A comparison of the pRB binding sites of the sequenced genital tract HPVs revealed a consistent amino acid difference (aspartic acid/glycine) between the high-risk and low-risk viruses. Single amino acid substitution mutations were generated at this position in the HPV-6 and HPV-16 E7 proteins, and this single amino acid residue was shown to be the principal determinant responsible for the differences in the apparent pRB binding affinity and transformation capacity distinguishing the HPV E7 proteins of the high-risk and low-risk HPVs.


Subject(s)
Cell Transformation, Neoplastic , Oncogene Proteins, Viral/genetics , Papillomaviridae/genetics , Retinoblastoma Protein/metabolism , Adenovirus Early Proteins , Adenoviruses, Human/genetics , Amino Acid Sequence , Animals , Binding Sites , Cell Line , Chloramphenicol O-Acetyltransferase/genetics , Chloramphenicol O-Acetyltransferase/metabolism , Cloning, Molecular , Escherichia coli/genetics , Genes, Viral , Genes, ras , Humans , Molecular Sequence Data , Oncogene Proteins, Viral/metabolism , Papillomavirus E7 Proteins , Protein Binding , Rats , Recombinant Fusion Proteins/metabolism , Sequence Homology, Nucleic Acid , Transfection
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