729 resultados para Atrophy
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PURPOSE: To report the first documented case of HLA-A29-positive birdshot chorioretinopathy in an African American patient. METHODS: A 51-year-old African American woman presented with a 10-year history of photopsia, progressive decrease in visual acuity, metamorphopsia, and new nyctalopia. Both fundi showed evidence of periphlebitis, arterial attenuation, macular edema, and diffuse chorioretinal atrophy. RESULTS: Fluorescein angiography revealed diffuse vascular leakage, and indocyanine green showed evenly distributed and symmetrical hypofluorescent spots, which were difficult to appreciate on fundoscopy. Workup revealed a positive HLA-A29 and was negative for sarcoid, tuberculosis, and syphilis. CONCLUSION: Birdshot chorioretinopathy overwhelmingly affects non-Hispanic Caucasians, but there have been rare reported cases in other ethnicities including Hispanics and African Americans. This patient's ethnicity may have contributed to the 10-year delay in diagnosis. To our knowledge, this is the first documented HLA-A29 positive case of birdshot chorioretinopathy in an African American. HLA-A29 may be a useful supportive test in cases with classic clinical presentation in non-Caucasian patients to enable the correct diagnose in a timely manner.
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INTRODUCTION: To describe the clinical outcomes of intravitreal ranibizumab treatment for subfoveal choroidal neovascularisation (CNV) associated with Stargardt disease. METHODS: Prospective, interventional, case series. All patients underwent intravitreal ranibizumab injections following a pro re nata regimen with monthly examination, over a 24-month follow-up. RESULTS: Three eyes were included in the study. Best corrected visual acuity changed from 0.47±0.06 (mean±SD) at baseline to 0.90±0.17 LogMAR at the end of the 24-month follow-up. Overall, a mean number of 11 ranibizumab injections were administered in 24 months. Significant atrophic growth was detected in all cases, with the mean atrophy area increasing from 2.34±2.60 mm(2) (mean±SD) at baseline to 4.23±3.31 mm(2) at the end of the follow-up. CONCLUSIONS: Ranibizumab treatment can stop the CNV progression, but cannot ensure a significant visual improvement. Macular atrophy tends to significantly enlarge under ranibizumab treatment over the follow-up. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
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Human lipocalin 2 is described as the neutrophil gelatinase-associated lipocalin (NGAL). The lipocalin 2 gene encodes a small, secreted glycoprotein that possesses a variety of functions, of which the best characterized function is organic iron binding activity. Elevated NGAL expression has been observed in many human cancers including breast, colorectal, pancreatic and ovarian cancers. I focused on the characterization of NGAL function in chronic myelogenous leukemia (CML) and breast cancer. Using the leukemic xenograft mouse model, we demonstrated that over-expression of NGAL in K562 cells, a leukemic cell line, led to a higher apoptotic rate and an atrophy phenotype in the spleen of inoculated mice compared to K562 cells alone. These results indicate that NGAL plays a primary role in suppressing hematopoiesis by inducing apoptosis within normal hematopoietic cells. In the breast cancer project, we analyzed two microarray data sets of breast cancer cell lines ( n = 54) and primary breast cancer samples (n = 318), and demonstrated that high NGAL expression is significantly correlated with several tumor characteristics, including negative estrogen receptor (ER) status, positive HER2 status, high tumor grade, and lymph node metastasis. Ectopic NGAL expression in non-aggressive (ZR75.1 and MCF7) cells led to aggressive tumor phenotypes in vitro and in vivo. Conversely, knockdown of NGAL expression in various breast cancer cell lines by shRNA lentiviral infection significantly decreased migration, invasion, and metastasis activities of tumor cells both in vitro and in vivo . It has been previously reported that transgenic mice with a mutation in the region of trans-membrane domain (V664E) of HER2 develop mammary tumors that progress to lung metastasis. However, we observed that genetic deletion of the 24p3 gene, a mouse homolog of NGAL, in HER2 transgenic mice by breeding with 24p3-null mice resulted in a significant delay of mammary tumor formation and reduction of lung metastasis. Strikingly, we also found that treatment with affinity purified 24p3 antibodies in the 4T1 breast cancer mice strongly reduced lung metastasis. Our studies provide evidence that NGAL plays a critical role in breast cancer development and progression, and thus NGAL has potential as a new therapeutic target in breast cancer.^
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Part 1: 1881-1888 On Some Points in the Etiology and Pathology of Ulcerative Endocarditis, 1881 On Certain Parasites in the Blood of the Frog, 1883 The Third Corpuscle of the Blood, 1883 On the Use of Arsenic in Certain Forms of Anaemia, 1886 Antifebrin, 1887 Case of Arterio-Venous Aneurism of the Axillary Artery and Vein of Fourteen Year's Duration, 1887 Typhilitis and Appendicitis, 1888 Part 2: 1889-1892 Annual Address - License to Practice 1889 Case of Syphiloma of the Cord of the Cauda Equina-Death From Diffuse Central Myelitis, 1889 On a Case of Simple Idiopathic Muscular Atrophy, Involving the Face and the Scapulo-Humeral Muscles, 1889 Note on Intra-Thoracic Growths Developing from the Thyroid Gland, 1889 On the Value of Laveran's Organisms in the Diagnosis of Malaria, 1889 On the Form of Convulsive Tic Associated with Corprolalia, Etc., 1890 A Case of Sensory Aphasia Word-blindness with Hemianopsia, 1891 Rudolf Virchow: The Man and the Student, 1891 The Healing of Tuberculosis, 1892 The Cold-Bath Treatment of Typhoid Fever, 1892 Part 3: 1893 Remarks on the Varieties of Chronic Chorea, and a Report Upon Two Families of the Hereditary Form, With One Autopsy, 1893 Note on Arsenical Neuritis Following the use of Fowler's Solution, 1893 Note on a Remarkable House Epidemic of Typhoid Fever, 1893 Cases of Sub-Phrenic Abscess, 1893 On Sporadic Cretinism in America, 1893 Notes on Tuberculosis in Children, 1893 Part 4: 1849-1895 Parotitis in Pneumonia, Case of Pericarditis Treated by Incision and Drainage, 1894 The Army Surgeon, 1894 Introductory Remarks to Course of Clinical Demonstrations on Typhoid Fever, 1894 Cancer of the Stomach with Very Rapid Course, 1895 Case of Sporadic Cretinism (Infantile Myxcedema) Treated Successfully with Thyroid Extract, 1895 Visible Contractile Tumour of the Pylorus Following Ulcer of the Stomach, 1895 On the Association of Enormous Heart Hypertrophy, Chronic Proliferative Peritonitis, and Recurring Ascites, with Adherent Pericardium, 1895 Teaching and Thinking the Two Functions of a Medical School, 1895 The Practical Value of Laveran's Discoveries, 1895 Part 5 1896 Addison's Disease, 1896 On Six Cases of Addison's Disease, 1896 Hemiplegia in Typhoid Fever Thomas Dover (of Dover's Powder) Physician and Buccaneer, 1896 John Keats The Apothecary Poet, 1896 On The Classification of the Tics or Habit Movements, 1896 The Cerebral Complication of Raynaud's Disease, 1896 Part 6: 1897 On Certain Features in the Prognosis of Pneumonia, 1897 Clinical Lecture on Mitral Stenosis - Sudden Death - Ball Thrombus in the Left Auricle, 1897 The Diagnosis of Malarial Fever, 1897 The Functions of a State Faculty (President's Address), 1897 A Clinical Lecture on The Ball-Valve Gall-Stone in the Common Duct, 1897 Pneumonia (Review of Cases studied), 1897 Internal Medicine as a Vocation, 1897 Back Notes
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La neurotoxina botulínica es producida por la bacteria anaerobia Clostridium botulinum (NTBo). Bloquea la transmisión neuromuscular por lo cual es utilizada para el tratamiento de enfermedades con hiperactividad muscular, bloqueando la liberación de acetilcolina y así la transmisión sináptica en la unión neuromuscular, lo que lleva al debilitamiento y atrofia de los músculos. Este mecanismo de acción motivó el uso de la toxina botulínica en las enfermedades con elevado tono muscular, como la distonía y la espasticidad, por lo cual también ha revolucionado la opción de tratamiento de los trastornos autónomos de hipersecreción. La sialorrea es un síntoma común en diversas enfermedades neurológicas. Las inyecciones de toxina botulínica, guiadas por ultrasonidos en las glándulas salivales, produce una disminución de la salivación excesiva en niños con deficiencias neurológicas como parálisis cerebral. La utilización de la toxina botulínica tipo A ha sido sugerida como tratamiento de la sialorrea en pacientes con parálisis cerebral (PC). Esta recomendación ha sido hecha por el efecto anticolinérgico de esta sustancia, principalmente por su capacidad para bloquear la liberación de acetilcolina a nivel de las membranas pre-sinápticas Aunque la respuesta al tratamrento es distinta en cada niño, en general se ha observado que cuanto más a menudo se utiliza la toxlna botulínica y más alta es la dosis utilizada, los resultados son mejores. Los expertos consideran conveniente el procedimiento porque muchos de estos pacientes están utilizando la toxina botulínica para sus problemas musculares y las distrntas condiciones pueden ser tratadas al mismo tiempo Se reporta la descripción de la aplicación de toxina botulínica en una paciente niña que concurre al Instituto de Rehabilitación Infantil TELETON de la ciudad de Valparaíso, Chile, con un trastorno motor severo y con salivación incontrolada persistente que provoca enfermedades respiratorias a repetición
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PURPOSE: To describe scleral changes in chronic VKH. METHODS: Medical records of patients with chronic VKH were retrospectively reviewed. Change of scleral architecture was defined as progressive posterior bowing on OCT, axial length elongation, and/or increased myopia more than -1.0 D, not explicable by other etiologies. RESULTS: In total, 28 eyes (16 patients) with mean age of disease onset 32.5 ± 14.0 years were included in the study. Disease duration was 15.1 ± 10.2 years. Eight eyes (28.6%) showed progressive scleral architectural changes. Five eyes (18%) developed scleral changes on OCT, not seen on prior imaging (2-12 years earlier). One eye had posterior bowing on OCT with increased axial length, both eyes of a bilateral pseudophake developed increased myopia with increased axial length. Well-circumscribed chorioretinal atrophy within the arcade was associated with progressive scleral change. CONCLUSIONS: Progressive scleral change may develop as a late complication of VKH. The association with well-circumscribed chorioretinal atrophy suggests that chronic choroidal inflammation may be responsible.
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PURPOSE To report acute/subacute vision loss and paracentral scotomata in patients with idiopathic multifocal choroiditis/punctate inner choroidopathy due to large zones of acute photoreceptor attenuation surrounding the chorioretinal lesions. METHODS Multimodal imaging case series. RESULTS Six women and 2 men were included (mean age, 31.5 ± 5.8 years). Vision ranged from 20/20-1 to hand motion (mean, 20/364). Spectral domain optical coherence tomography demonstrated extensive attenuation of the external limiting membrane, ellipsoid and interdigitation zones, adjacent to the visible multifocal choroiditis/punctate inner choroidopathy lesions. The corresponding areas were hyperautofluorescent on fundus autofluorescence and were associated with corresponding visual field defects. Full-field electroretinogram (available in three cases) showed markedly decreased cone/rod response, and multifocal electroretinogram revealed reduced amplitudes and increased implicit times in two cases. Three patients received no treatment, the remaining were treated with oral corticosteroids (n = 4), oral acyclovir/valacyclovir (n = 2), intravitreal/posterior subtenon triamcinolone acetate (n = 3), and anti-vascular endothelial growth factor (n = 2). Visual recovery occurred in only three cases of whom two were treated. Varying morphological recovery was found in six cases, associated with decrease in hyperautofluorescence on fundus autofluorescence. CONCLUSION Multifocal choroiditis/punctate inner choroidopathy can present with transient or permanent central photoreceptor attenuation/loss. This presentation is likely a variant of multifocal choroiditis/punctate inner choroidopathy with chorioretinal atrophy. Associated changes are best evaluated using multimodal imaging.
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Early weaning is a stressful event characterized by a transient period of intestinal atrophy that may be mediated by reduced secretion of glucagon-like peptide (GLP) 2. We tested whether enterally fed bile acids or plant sterols could increase nutrient-dependent GLP-2 secretion and improve intestinal adaptation in weanling pigs. During the first 6 d after weaning, piglets were intragastrically infused once daily with either deionized water -control-, chenodeoxycholic acid -CDC; 60mg/kg body weight-, or b-sitoesterol -BSE; 100 mg/kg body weight-. Infusing CDC increased plasma GLP-2 -P menor que 0.05- but did not affect plasma GLP-1 and feed intake. The intestinal expression of Glp2r -glucagon-like peptide 2 receptor-, Asbt -sodium-dependent bile acid transporter-, Fxr -farnesoid X receptor-, and Tgr5 -guanosine protein?coupled bile acid receptor- genes were not affected by CDC treatment. The intragastric administration of CDC did not alter the weight and length of the intestine, yet increased the activation of caspase-3 in ileal villi -P menor que 0.02- and the expression of Il6 -interleukin 6; P menor que 0.002- in the jejunum. In contrast, infusing BSE did not affect any of the variables that were measured. Our results show that the enteral administration of the bile acid CDC potentiates the nutrient-induced secretion of endogenous GLP-2 in early-weaned pigs. Bile acid?enhanced release of GLP-2, however, did not result in improved intestinal growth, morphology, or inflammation during the postweaning degenerative phase.
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Many proteins contain reiterated glutamine residues, but polyglutamine of excessive length may result in human disease by conferring new properties on the protein containing it. One established property of a glutamine residue, depending on the nature of the flanking residues, is its ability to act as an amine acceptor in a transglutaminase-catalyzed reaction and to make a glutamyl–lysine cross-link with a neighboring polypeptide. To learn whether glutamine repeats can act as amine acceptors, we have made peptides with variable lengths of polyglutamine flanked by the adjacent amino acid residues in the proteins associated with spinocerebellar ataxia type 1 (SCA1), Machado–Joseph disease (SCA3), or dentato-rubral pallido-luysian atrophy (DRPLA) or those residues adjacent to the preferred cross-linking site of involucrin, or solely by arginine residues. The polyglutamine was found to confer excellent substrate properties on any soluble peptide; under optimal conditions, virtually all the glutamine residues acted as amine acceptors in the reaction with glycine ethyl-ester, and lengthening the sequence of polyglutamine increased the reactivity of each glutamine residue. In the presence of transglutaminase, peptides containing polyglutamine formed insoluble aggregates with the proteins of brain extracts and these aggregates contained glutamyl–lysine cross-links. Repeated glutamine residues exposed on the surface of a neuronal protein should form cross-linked aggregates in the presence of any transglutaminase activated by the presence of Ca2+.
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Streptozotocin (STZ), a glucose analogue known to induce diabetes in experimental animals, causes DNA strand breaks and subsequent activation of poly(ADPribose) polymerase (Parp). Because Parp uses NAD as a substrate, extensive DNA damage will result in reduction of cellular NAD level. In fact, STZ induces NAD depletion and cell death in isolated pancreatic islets in vitro. Activation of Parp therefore is thought to play an important role in STZ-induced diabetes. In the present study, we established Parp-deficient (Parp−/−) mice by disrupting Parp exon 1 by using the homologous recombination technique. These mice were used to examine the possible involvement of Parp in STZ-induced β-cell damage in vivo. The wild-type (Parp+/+) mice showed significant increases in blood glucose concentration from 129 mg/dl to 218, 370, 477, and 452 mg/dl on experimental days 1, 7, 21, and 60, respectively, after a single injection of 180 mg STZ/kg body weight. In contrast, the concentration of blood glucose in Parp−/− mice remained normal up to day 7, slightly increased on day 21, but returned to normal levels on day 60. STZ injection caused extensive necrosis in the islets of Parp+/+ mice on day 1, with subsequent progressive islet atrophy and loss of functional β cells from day 7. In contrast, the extent of islet β-cell death and dysfunction was markedly less in Parp−/− mice. Our findings clearly implicate Parp activation in islet β-cell damage and glucose intolerance induced by STZ in vivo.
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Accurate and automated methods for measuring the thickness of human cerebral cortex could provide powerful tools for diagnosing and studying a variety of neurodegenerative and psychiatric disorders. Manual methods for estimating cortical thickness from neuroimaging data are labor intensive, requiring several days of effort by a trained anatomist. Furthermore, the highly folded nature of the cortex is problematic for manual techniques, frequently resulting in measurement errors in regions in which the cortical surface is not perpendicular to any of the cardinal axes. As a consequence, it has been impractical to obtain accurate thickness estimates for the entire cortex in individual subjects, or group statistics for patient or control populations. Here, we present an automated method for accurately measuring the thickness of the cerebral cortex across the entire brain and for generating cross-subject statistics in a coordinate system based on cortical anatomy. The intersubject standard deviation of the thickness measures is shown to be less than 0.5 mm, implying the ability to detect focal atrophy in small populations or even individual subjects. The reliability and accuracy of this new method are assessed by within-subject test–retest studies, as well as by comparison of cross-subject regional thickness measures with published values.
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We report that 9 d of uncontrolled experimental diabetes induced by streptozotocin (STZ) in rats is an endogenous chronic stressor that produces retraction and simplification of apical dendrites of hippocampal CA3 pyramidal neurons, an effect also observed in nondiabetic rats after 21 d of repeated restraint stress or chronic corticosterone (Cort) treatment. Diabetes also induces morphological changes in the presynaptic mossy fiber terminals (MFT) that form excitatory synaptic contacts with the proximal CA3 apical dendrites. One effect, synaptic vesicle depletion, occurs in diabetes as well as after repeated stress and Cort treatment. However, diabetes produced other MFT structural changes that differ qualitatively and quantitatively from other treatments. Furthermore, whereas 7 d of repeated stress was insufficient to produce dendritic or synaptic remodeling in nondiabetic rats, it potentiated both dendritic atrophy and MFT synaptic vesicle depletion in STZ rats. These changes occurred in concert with adrenal hypertrophy and elevated basal Cort release as well as hypersensitivity and defective shutoff of Cort secretion after stress. Thus, as an endogenous stressor, STZ diabetes not only accelerates the effects of exogenous stress to alter hippocampal morphology; it also produces structural changes that overlap only partially with those produced by stress and Cort in the nondiabetic state.
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Spinal muscular atrophy (SMA) is attributed to mutations in the SMN1 gene, leading to loss of spinal cord motor neurons. The neurotropic Sindbis virus vector system was used to investigate a role for the survival motor neuron (SMN) protein in regulating neuronal apoptosis. Here we show that SMN protects primary neurons and differentiated neuron-like stem cells, but not cultured cell lines from virus-induced apoptotic death. SMN also protects neurons in vivo and increases survival of virus-infected mice. SMN mutants (SMNΔ7 and SMN-Y272C) found in patients with SMA not only lack antiapoptotic activity but also are potently proapoptotic, causing increased neuronal apoptosis and animal mortality. Full-length SMN is proteolytically processed in brains undergoing apoptosis or after ischemic injury. Mutation of an Asp-252 of SMN abolished cleavage of SMN and increased the antiapoptotic function of full-length SMN in neurons. Taken together, deletions or mutations of the C terminus of SMN that result from proteolysis, splicing (SMNΔ7), or germ-line mutations (e.g., Y272C), produce a proapoptotic form of SMN that may contribute to neuronal death in SMA and perhaps other neurodegenerative disorders.
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Opiates are potent analgesic and addictive compounds. They also act on immune responses, and morphine, the prototypic opiate, has been repeatedly described as an immunosuppressive drug. Pharmacological studies have suggested that the inhibitory action of opiates on immunity is mediated by multiple opioid receptor sites but molecular evidence has remained elusive. Recently, three genes encoding μ- (MOR), δ-, and κ-opioid receptors have been cloned. To investigate whether the μ-opioid receptor is functionally implicated in morphine immunosuppression in vivo, we have examined immune responses of mice with a genetic disruption of the MOR gene. In the absence of drug, there was no difference between wild-type and mutant mice with regard to a large number of immunological endpoints, suggesting that the lack of MOR-encoded protein has little consequence on immune status. Chronic morphine administration induced lymphoid organ atrophy, diminished the ratio of CD4+CD8+ cells in the thymus and strongly reduced natural killer activity in wild-type mice. None of these effects was observed in MOR-deficient mice after morphine treatment. This demonstrates that the MOR gene product represents a major molecular target for morphine action on the immune system. Because our previous studies of MOR-deficient mice have shown that this receptor protein is also responsible for morphine analgesia, reward, and physical dependence, the present results imply that MOR-targeted therapeutic drugs that are developed for the treatment of pain or opiate addiction may concomitantly influence immune responses.
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Spinal muscular atrophy is caused by defects in the survival motor neuron (SMN) gene. To better understand the patterns of expression of SMN in neuronal cells and tissues, we raised a polyclonal antibody (abSMN) against a synthetic oligopeptide from SMN exon 2. AbSMN immunostaining in neuroblastoma cells and mouse and human central nervous system (CNS) showed intense labeling of nuclear “gems,” along with prominent nucleolar immunoreactivity in mouse and human CNS tissues. Strong cytoplasmic labeling was observed in the perikarya and proximal dendrites of human spinal motor neurons but not in their axons. Immunoblot analysis revealed a 34-kDa species in the insoluble protein fractions from human SY5Y neuroblastoma cells, embryonic mouse spinal cord cultures, and human CNS tissue. By contrast, a 38-kDa species was detected in the cytosolic fraction of SY5Y cells. We conclude that SMN protein is expressed prominently in both the cytoplasm and nucleus in multiple types of neurons in brain and spinal cord, a finding consistent with a role for SMN as a determinant of neuronal viability.