19 resultados para Aneurysm dissecting
Resumo:
Part 1: 1898-1899 On Chronic Symmetrical Enlargement of the Salivary and Lachrymal Glands, 1898 Leprosy in the United States, with the Report of a Case, 1898 An Acute Myxaedematous Condition, with Tachycardia, Glycosuria, Melaena, Mania and Death, 1898 On some of the Intestinal Features of Typhoid Fever, 1898 Cerebro-Spinal Fever, 1898 The Arthritis of Cerebro-Spinal Fever, 1898 In Memoriam, William Pepper, 1899 After Twenty-Five Years, 1899 The Diagnosis of Typhoid Fever, 1899 Interstitial Processes in the Central Nervous System, 1899 Part 2: 1900 The Home Treatment of Consumption, 1900 On Splenic Anaemia, 1900 The Chronic Intermittent Fever of Endocarditis, 1900 A Case of Multiple Gangrene in Malarial Fever, 1900 Latent Cancer of the Stomach, 1900 On the Study of Tuberculosis, 1900 Fatal Angina Pectoris without Lesions of the Coronary Arteries of a Young Man, 1900 On the Advantages of a Trace of Albumin and a Few Casts in the Urine of Certain Men above Fifty Years of Age, 1900 Part 3: 1901-1902 Congenital Absence of the Abdominal Muscles with Distended Hypertrophied Urinary Bladder, 1901 Intermittent Claudication, 1902 On the Diagnosis of Bilateral Cystic Kidney, 1902 On Amebic Abscess of the Liver, 1902 Note on the Occurrence of Ascites in Solid Abdominal Tumors, 1902 Amebic Dysentery, 1902 Notes on Aneurism, 1902 William Beaumont; a Pioneer American Physiologist, 1902 Part 4: 1903 On the Educational Value of the Medical Society, 1903 On obliteration of the Superior Vena Cava,1903 Chronic Cyanosis, with Polycythemia and Enlarged Spleen: A New Clinical Entity, 1903 The Home and its Relation to the Tuberculosis Problem, 1903 Unity, Peace, and Concord, 1903 Typhoid Fever and Tuberculosis, 1903 Part 5: 1904-1906 Ochronosis, 1904 The “Phthisiologia” of Richard Morton, M.D., 1904 On the Surgical Importance of the Visceral Crises In the Erythema Group of Skin Diseases, 1904 Aneurysm of the Abdominal Aorta, 1905 Back Notes
Resumo:
Part 1: 1907-1908 The Royal Medical Society of Edinburg, 1907 On the Library of a Medical School, 1907 On Telangiectasis Circumscripta Universalis, 1907 A Clinical Lecture on Abdominal Tumours Associated with Disease of the Testicle, 1907 A Clinical Lecture on Erythraemia, 1908 Vienna after Thirty-Four Years, 1908 Endocardites Infectieuses Chroniques, 1908 Part 2: 1909 Chronic Infectious Endocarditis, 1909 What the Public Can Do in the Fight Against Tuberculosis, 1909 Annual Oration on the Occasion of the Opening of the New Building of the Medical and Chirurgical Faculty of the State of Maryland, May 13, 1909 The Medical Library in Post-Graduate Work, 1909 The Treatment of Disease, 1909 Part 3: 1910-1911 The Pupil Symptoms in Thoracic Aneurysm, 1910 The Lumleian Lectures on Angina Pectoris, 1910 Certain Vasomotor, Sensory, and Muscular Phenomena Associated with Cervical Rib, 1910 An Address on the Hospital Unit in University Work, 1911 Sulle Telangiectasie Emorragiche Ereditarie, 1911 Transient Attacks of Aphasia and Paralyses in States of High Blood Pressure and Arterio-Sclerosis, 1911 The Pathological Institute of a General Hospital, 1911 Part 4: 1912-1914 An Address on High Blood Pressure: its Associations, Advantages, and Disadvantages, 1912 Specialism in the General Hospital, 1913 Syphilis of the Liver with the Picture of Banti’s Disease, 1913 An Introductory Address on Examinations, Examiners, and Examinees, 1913 The Medical Clinic: a retrospect and a Forecast, 1914 Part 5: 1915-1919 Remarks on the Diagnosis of Polycystic Kidney, 1915 The War and Typhoid Fever, 1914/15 The Cerebro-Spinal Fever in Camps and Barracks, 1915 Remarks on Arterio-Venous Aneurysm, 1915 Nerve & “Nerves”, 1915 Intensive Work in Science at the Public Schools in Relation to the Curriculum, 1916 Creators, Transmuters, and Transmitters, 1916 Annual Oration on the Campaign Against Syphilis, 1917 The First Printed Documents relating to Modern Surgical Anaesthesia, 1918 Observations on the Severe Anaemias of Pregnancy and the Post-Partum State, 1919 Typhoid Spine, 1919
Resumo:
Thoracic aortic aneurysms and dissections (TAAD) are the primary disease affecting the thoracic ascending aorta, with an incidence rate of 10.4/100,000. Although about 20% of patients carry a mutation in a single gene that causes their disease, the remaining 80% of patients may also have genetic factors that increase their risk for developing TAAD. Many of the genes that predispose to TAAD encode proteins involved in smooth muscle cell (SMC) contraction and the disease-causing mutations are predicted to disrupt contractile function. SMCs are the predominant cell type in the ascending aortic wall. Mutations in MYH11, encoding the smooth muscle specific myosin heavy chain, are a rare cause of inherited TAAD. However, rare but recurrent non-synonymous variants in MYH11 are present in the general population but do not cause inherited TAAD. The goal of this study was to assess the potential role of these rare variants in vascular diseases. Two distinct variants were selected: the most commonly seen rare variant, MYH11 R247C, and a duplication of the chromosomal region spanning the MYH11 locus at 16p13.1. Genetic analyses indicated that both of these variants were significantly enriched in patients with TAAD compared with controls. A knock-in mouse model of the Myh11 R247C rare variant was generated, and these mice survive and reproduce normally. They have no structural abnormalities of the aorta or signs of aortic disease, but do have decreased aortic contractility. Myh11R247C/R247C mice also have increased proliferative response to vascular injury in vivo and increased proliferation of SMCs in vitro. Myh11R247C/R247C SMCs have decreased contractile gene and protein expression and are dedifferentiated. In fibroblasts, myosin force generation is required for maturation of focal adhesions, and enhancers of RhoA activity replace enhancers of Rac1 activity as maturation occurs. Consistent with these previous findings, focal adhesions are smaller in Myh11R247C/R247C SMCs, and there is decreased RhoA activation. A RhoA activator (CN03) rescues the dedifferentiated phenotype of Myh11R247C/R247C SMCs. Myh11R247C/R247C mice were bred with an existing murine model of aneurysm formation, the Acta2-/- mouse. Over time, mice carrying the R247C allele in conjunction with heterozygous or homozygous loss of Acta2 had significantly increased aortic diameter, and a more rapid accumulation of pathologic markers. These results suggest that the Myh11 R247C rare variant acts as a modifier gene increasing the risk for and severity of TAAD in mice. In patients with 16p13.1 duplications, aortic MYH11 expression is increased, but there is no corresponding increase in smooth muscle myosin heavy chain protein. Using SMCs that overexpress Myh11, we identified alterations in SMC phenotype leading to excessive protein turnover. All contractile proteins, not just myosin, are affected, and the proteins are turned over by autophagic degradation. Surprisingly, these cells are also more contractile compared with wild-type SMCs. The results described in this dissertation firmly establish that rare variants in MYH11 significantly affect the phenotype of SMCs. Further, the data suggests that these rare variants do increase the risk of TAAD via pathways involving altered SMC phenotype and contraction. Therefore, this study validates that these rare genetic variants alter vascular SMCs and provides model systems to explore the contribution of rare variants to disease.
Resumo:
The neuropeptide somatostatin is a widely distributed general inhibitor of endocrine, exocrine, gastrointestinal and neural functions. The biological actions of somatostatin are initiated by interaction with high affinity, plasma membrane somatostatin receptors (sst receptors). Five sst receptor subtypes have been cloned and sequence analysis shows they are all members of the G protein coupled receptor superfamily. The G proteins play a pivotal role in sst receptor signal transduction and the specificity of somatostatin receptor-G protein coupling defines the possible range of cellular responses. However, the data for endogenous sst receptor and G protein coupling is very limited, and even when it is available, the sst receptor subtypes involved in G protein coupling and signal transduction are unknown due to the expression of multiple sst receptor subtypes in target cell lines or tissues of somatostatin.^ In an effort to characterize each individual sst receptor subtypes, antisera against unique C-terminal regions of different sst receptor subtypes have been developed in our lab. In this report, antisera made against the sst1, sst2A and sst4 receptors are characterized. They are highly specific to their corresponding receptors and efficiently immunoprecipitate the sst receptors. Using these antibodies, the cell lines expressing these sst receptor subtypes were identified with both immunoprecipitation and Western blot methods. The development of sst receptor subtype specific antibodies make it possible to determine the specificity of the sst receptor subtype and G protein coupling in target cells or tissues expressing multiple sst receptors, two questions were addressed by this thesis: (1) whether different cellular environments affect receptor subtype and G protein coupling; (2) whether different sst receptors couple to different G proteins in similar cellular environments.^ Taken together our findings, both sst1 and sst2A receptors couple with G$\alpha\sb{\rm i1},$ G$\alpha\sb{\rm i2}$ and G$\alpha\sb{\rm i3}$ in CHO cells, G$\alpha\sb{\rm i2}$ and G$\alpha\sb{\rm i3}$ in GH$\sb4$C$\sb1$ cells. Further, sst2A receptors couple with G$\alpha\sb{\rm i1},$ G$\alpha\sb{\rm i2}$ and G$\alpha\sb{\rm i3}$ in AR4-2J cells while sst4 receptors couple with G$\alpha\sb{\rm i2}$ and G$\alpha\sb{\rm i3}$ in CHO cells. Therefore, the G protein coupling of the same sst receptors in different cell lines is basically similar in that they all couple with multiple $\alpha$-subunits of the G$\rm \sb{i}$ proteins, suggesting cellular environment has little effect on receptor and G protein coupling. Moreover, different sst receptors have similar G protein coupling specificities in the same cell line, suggesting components other than receptor and G$\alpha$ subunits in the signal transduction pathways may contribute to specific functions of each sst receptor subtype. This series of experiments represent a novel approach in dissecting signal transduction pathways and may have general application in the field. Furthermore, this is the first systematic study of sst receptor subtype and G protein $\alpha$-subunit interaction in both transfected cells and in normal cell lines. The information generated will be very useful in our understanding of sst receptor signal transduction pathways and in directing future sst receptor research. ^