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1.
BMC Surg ; 22(1): 436, 2022 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-36544128

RESUMEN

BACKGROUND: In locally advanced breast cancer, axillary lymph node dissection remains a pivotal component of surgical therapy. Apart from this, it has been mostly replaced by sentinel node biopsy. Complications after axillary dissection include wound infection, neuropathy, lymphedema and-most frequently-seroma. In this retrospective multi-centre study, we compared the use of LigaSureTM with monopolar electrocautery regarding perioperative outcome. METHODS: A retrospective data analysis from female breast cancer patients who underwent axillary dissection at two breast centres in Austria that are using two different surgical techniques was performed for this study. We compared the rate of complications and re-operations, length of hospital stay, time to drain removal, total drain fluid, seroma formation after drain removal, number of seroma aspirations and total seroma fluid. RESULTS: Seventy one female patients with a median age of 63 (30-83) were included in this study. In 35 patients LigaSureTM and in 36 monopolar cautery was used for axillary dissection. There was no significant difference regarding intraoperative complications and rate of re-operations between the two groups (2.9 vs. 5.6%; p = 1 and 2.9 vs. 13.9%; p = 0.199). The time to drain removal and the length of hospital stay was similar in both groups. A significant difference in the occurence of postoperative wound infection could also not be shown. However, we found a significantly smaller total drain fluid in the LigaSureTM-group compared to the cautery-group (364.6 ml vs. 643.4 ml; p = 0.004). Seroma formation after drain removal was more frequent in the LigaSureTM-group (68.6 vs. 41.7%; p = 0.032) with a higher number of outpatient seroma aspirations (2.0 vs. 0.9; p = 0.005). CONCLUSION: LigaSureTM and monopolar cautery provide equivalent techniques in axillary lymph node dissection with comparable postoperative outcomes.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/patología , Estudios Retrospectivos , Seroma/epidemiología , Seroma/etiología , Escisión del Ganglio Linfático/métodos , Drenaje/métodos , Axila/cirugía , Axila/patología
2.
J La State Med Soc ; 169(2): 51, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28414672

RESUMEN

CASE: A 48 year-old man with no past medical history was sent to our emergency department (ED); from a primary care clinic for hypertensive urgency of 200/130. The man reported an intermittent non-productive cough of approximately one year's duration and worsening dyspnea on exertion and orthopnea over the last month with lower extremity swelling. Of note, he emigrated from Honduras twenty years ago. Blood pressure normalized with administration of Lasix in the ED. Physical exam revealed rales in lung bases bilaterally, jugular venous distension, lower extremity pitting edema with serpiginous patches of erythema and excoriation, and a cardiac gallop. Labs showed peripheral eosinophilia, thrombocytopenia, elevated creatinine, hyperbilirubinemia, hyperglycemia, and mild transaminitis. Transthoracic echocardiogram revealed a dilated left ventricle with global hypokinesis and severely depressed systolic function with an ejection fraction less than 15 percent . The patient was diuresed, and subsequent left and right heart catheterizations were normal. CT chest showed a small nodule in the right upper lobe. Tests for Coccidiosis, Trypanosoma cruzi, and Mycobacterium tuberculosis were negative; however the acid fast bacilli culture grew Mycobacterium fortuitum. A Strongyloides stercoralis antibody test was positive, and the patient was treated with two doses of oral ivermectin with one dose of intravenous ceftriaxone, and discharged. Two months later, his eosinophilia resolved, but he remained symptomatic with productive cough and weight loss, and was started on an outpatient course of oral ciprofloxacin and trimethoprim-sulfamethozole for M. fortuitum. DISSCUSION: Strongyloides-infected patients may carry the parasite for years without prominent symptoms. Endemic throughout South America, Strongyloides persists in its hosts through a lifecycle of autoinfection, which, over time, increases parasite burden and can lead to a hyperinfection syndrome whereby filiariform larvae penetrate organ tissue, most commonly: heart, central nervous system, lungs and liver. We suspect chronic eosinophilia and disseminated filiaria to be the etiology of the non-ischemic dilated cardiomyopathy in this patient. Standard treatment of strongyloidiasis is ivermectin, however, mortality owing to transient bacteremia in the setting of hyperinfection syndrome is high. Therefore, bacteremia prophylaxis with gram negative rod coverage should be considered before antiparasitic agent initiation.

3.
Phys Rev Lett ; 117(9): 095501, 2016 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-27610863

RESUMEN

We report on the first observation of an approximant structure to the recently discovered two-dimensional oxide quasicrystal. Using scanning tunneling microscopy, low-energy electron diffraction, and surface x-ray diffraction in combination with ab initio calculations, the atomic structure and the bonding scheme are determined. The oxide approximant follows a 3^{2}.4.3.4 Archimedean tiling. Ti atoms reside at the corners of each tiling element and are threefold coordinated to oxygen atoms. Ba atoms separate the TiO_{3} clusters, leading to a fundamental edge length of the tiling 6.7 Å.

4.
Ultraschall Med ; 36(1): 40-6, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25255236

RESUMEN

PURPOSE: To examine combined first trimester screening (FTS), noninvasive prenatal testing (NIPT) and a two-step policy that combines FTS and NIPT in screening for aneuploidy. MATERIALS AND METHODS: Retrospective study involving 21,052 pregnancies where FTS was performed at the Praxis Praenatal.de in Duesseldorf, Germany. In each case, the sum risk of trisomy 21, 18 and 13 was computed. We assumed that NIPT detects 99 %, 98 %, 90 % and 99 % of cases with trisomy 21, 18, 13 and sex chromosomal abnormalities and that the false-positive rate is 0.5 %. The following screening policies were examined: NIPT or FTS with sum risk cut-offs of 1 in 50 and 1 in 250 in all patients or a two-step-policy with FTS in all patients followed by NIPT in the intermediate sum risk group. For the intermediate risk group, sum risk cut-offs of 1 in 50 and 1 in 1000 and 1 in 150 and 1 in 500 were used. RESULTS: There were 127, 34, 13 and 15 pregnancies with trisomy 21, 18, 13 and sex chromosomal abnormalities. 23 fetuses had other chromosomal abnormalities with an increased risk for adverse outcome that are not detectable by NIPT. 20,840 pregnancies were classified as normal as ante- and postnatal examinations did not show any signs of clinically significant chromosomal abnormalities. FTS with a sum risk cut-off of 1 in 50 and 1 in 250 detects 81 % and 91 % for all aneuploidies. NIPT detects 88 % of the respective pregnancies. The 2-step approach with sum risk cut-offs of 1 in 50 and 1 in 1000 detects 94 % of all aneuploidies. With sum risk cut-offs of 1 in 150 and 1 in 500, the detection rate is 93 %. CONCLUSION: A 2-step policy with FTS for all patients and NIPT in the intermediate risk group results in the highest detection rate of all aneuploidies.


Asunto(s)
Aberraciones Cromosómicas , Primer Trimestre del Embarazo , Diagnóstico Prenatal , Ultrasonografía Prenatal , Adulto , Trastornos de los Cromosomas/diagnóstico por imagen , Trastornos de los Cromosomas/embriología , Cromosomas Humanos Par 13/diagnóstico por imagen , Cromosomas Humanos Par 18/diagnóstico por imagen , Síndrome de Down/diagnóstico por imagen , Síndrome de Down/embriología , Femenino , Alemania , Humanos , Valor Predictivo de las Pruebas , Embarazo , Resultado del Embarazo , Estudios Retrospectivos , Aberraciones Cromosómicas Sexuales/embriología , Trisomía , Síndrome de la Trisomía 13 , Síndrome de la Trisomía 18
5.
Ultraschall Med ; 34(2): 157-61, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22161619

RESUMEN

PURPOSE: To compare various gestational ages and thresholds for diagnosing bowel dilatation in fetuses with gastroschisis and to evaluate the prognostic value of bowel dilatation for predicting postnatal bowel atresia and neonatal outcomes. MATERIALS AND METHODS: This was a retrospective observational study conducted from March 1997 to September 2009 that included 78 pregnancies with fetal gastroschisis. The predictive value of prenatal bowel dilatation for neonatal bowel atresia and postnatal complications was investigated in three subgroups: those with bowel dilatations ≥ 10 mm at a gestational age < 27 + 0 weeks, ≥ 10 mm at a gestational age < 30 + 0 weeks and ≥ 18 mm at a gestational age ≥ 30 weeks. RESULTS: Prenatally, 6 %, 81 % and 13 % of the bowel malformations were identified in the first, second and third trimesters, respectively. There were three stillbirths and three neonatal deaths, and the mean gestational age at delivery was 35.4 weeks (range 31 + 4 to 41 + 6). Bowel atresia was significantly correlated with prenatal bowel dilatation in all three subgroups. Bowel dilatations of ≥ 10 mm before 30 + 0 gestational weeks achieved the best performance in predicting bowel atresia, with a sensitivity of 89 % (8 / 9) and a specificity of 79 % (30 / 38). A prenatal bowel diameter ≥ 10 mm through 30 completed weeks was also the best predictor of a prolonged neonatal hospital stay ≥ 8 weeks (sensitivity = 61.1, 11 / 18, p = 0.002). CONCLUSION: Fetuses with isolated gastroschisis successfully underwent postnatal surgery in most cases (93.2 %), except for one termination, one intrauterine death and 3 cases of neonatal death. A fetal bowel dilatation > 10 mm before 30 + 0 weeks had the highest predictive value for postnatal bowel complications.


Asunto(s)
Gastrosquisis/diagnóstico por imagen , Atresia Intestinal/diagnóstico por imagen , Intestinos/diagnóstico por imagen , Primer Trimestre del Embarazo , Segundo Trimestre del Embarazo , Ultrasonografía Prenatal/métodos , Dilatación Patológica , Femenino , Muerte Fetal , Gastrosquisis/cirugía , Humanos , Recién Nacido , Unidades de Cuidado Intensivo Neonatal , Atresia Intestinal/cirugía , Intestinos/patología , Tiempo de Internación , Masculino , Embarazo , Pronóstico , Sensibilidad y Especificidad , Estadística como Asunto , Mortinato , Adulto Joven
6.
Rev Med Suisse ; 9(383): 895-7, 2013 Apr 24.
Artículo en Francés | MEDLINE | ID: mdl-23697085

RESUMEN

In the literature, uses of the internet by patients are interpreted either as a resource supporting their autonomy, or as a source of perturbation in the doctor-patient relationship. Analysing 50 interviews with pregnant women, this article aims at describing the different uses made during pregnancy. Some women mostly aim at sharing their experience in their use of internet. Others are looking for specialised information, by curiosity, to complement the information received in medical visits or, more rarely, as a result of a lack of information in their exchanges with professionals. Uses of internet by patients will develop in the future and it is important that professionals take into account these different forms of internet use in their practices.


Asunto(s)
Educación en Salud , Conducta en la Búsqueda de Información , Internet , Mujeres Embarazadas , Adulto , Femenino , Humanos , Embarazo
7.
Int J Cancer ; 129(7): 1611-23, 2011 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-21484797

RESUMEN

Pancreatic ductal adenocarcinomas are invariably lethal, and developing effective treatments that have minimal side effects is a challenge. Previous studies from our laboratory have shown that conjugates of cell membrane disrupting lytic peptides and luteinizing hormone releasing hormone (LHRH) target and destroy human prostate and breast cancer cells in xenografts in the nude mouse model (Hansel et al., Mol Cell Endocrinol 2007;260-262:183-9; Hansel et al., Mol Cell Endocrinol 2007;269:26-33), which express LHRH receptors. The objectives of our study were to synthesize a bioconjugate of LHRH analog ([DLys(6)]-LHRH) and a dietary microchemical (curcumin) and test the hypothesis that [DLys(6)]-LHRH-curcumin targets and inhibits pancreatic cancer cell growth in vitro and in vivo. In in vitro studies, we determined by confocal microscopy, flow cytometry analysis and reverse transcriptase-polymerase chain reaction that MIAPaCa-2, Panc-1 and BxPC-3 pancreatic cancer cell lines express LHRH receptors. [DLys(6)]-LHRH-curcumin inhibited cell proliferation of pancreatic cancer cell lines and induced apoptotic cell death (p < 0.05). Apoptosis was induced by cleavage of polyadenosine-5'-diphosphate-ribose-polymerase and caspase-3. The activity of [DLys(6)]-LHRH-curcumin was equal to free curcumin at equimolar concentrations in vitro. Unlike curcumin itself, the [DLys(6)]-LHRH-curcumin conjugate is water soluble which allows its intravenous administration. In two in vivo studies, [DLys(6)]-LHRH-curcumin given intravenously caused a significant (p < 0.01) reduction in tumor weights and volumes, and free curcumin given by gavage at an equal dose failed to cause a significant reduction in tumor weights and volumes in the nude mouse pancreatic cancer model. [DLys(6)]-LHRH-curcumin treatment enhanced apoptosis compared to [DLys(6)]-LHRH and vehicle-treated controls in tumor tissue. In conclusion, [DLys(6)]-LHRH-curcumin may be useful in treating pancreatic cancer.


Asunto(s)
Antineoplásicos/farmacología , Curcumina/administración & dosificación , Curcumina/farmacología , Hormona Liberadora de Gonadotropina/administración & dosificación , Hormona Liberadora de Gonadotropina/farmacología , Neoplasias Pancreáticas/patología , Animales , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Humanos , Masculino , Ratones , Ratones Desnudos , Trasplante de Neoplasias , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/metabolismo , Receptores LHRH/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto
8.
Ultrasound Obstet Gynecol ; 37(4): 444-9, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20645398

RESUMEN

OBJECTIVE: To examine the prevalence of reversed a-wave in the ductus venosus, tricuspid regurgitation and absent nasal bone, in a second-trimester population undergoing amniocentesis, after exclusion of major fetal defects and to estimate the performance in screening for trisomy 21 based on maternal age and these markers in a general population. METHODS: This was a retrospective study involving pregnancies undergoing amniocentesis due to increased risk for trisomy 21, mainly because of advanced maternal age. Before the invasive procedure, an ultrasound examination was carried out to exclude major fetal defects and to examine the ductus venosus, tricuspid blood flow and the presence of the fetal nasal bone. Modeling techniques were used based on 20 000 euploid pregnancies and 20 000 pregnancies with trisomy 21 to assess the screening performance in a general population. RESULTS: The study population consisted of 3613 euploid pregnancies and 35 cases with trisomy 21. In the euploid group, reversed flow in the ductus venosus, tricuspid regurgitation and an absent nasal bone was observed in 1.7%, 1.5% and 0.1% of cases, respectively. In the trisomic group, these markers were found in 14.3%, 11.4% and 14.3% of cases, respectively. For a 5% false-positive rate, the detection rate in screening for trisomy 21, based on maternal age and either ductus venosus, tricuspid blood flow or nasal bone would be 33.8%, 32.4% or 31.4%, respectively. Screening by maternal age alone would detect 29.0% of the fetuses with trisomy 21. Receiver-operating characteristics curve analysis showed a slight but significant improvement in screening performance for trisomy 21 based on the inclusion of these markers. CONCLUSION: Second-trimester ultrasound screening for trisomy 21 based on maternal age with additional assessment of the ductus venosus, tricuspid blood flow and the fetal nasal bone in otherwise normal-appearing fetuses is only marginally better than is screening by maternal age alone.


Asunto(s)
Síndrome de Down/diagnóstico por imagen , Hueso Nasal/diagnóstico por imagen , Venas Umbilicales/diagnóstico por imagen , Vena Cava Inferior/diagnóstico por imagen , Adulto , Amniocentesis , Biomarcadores/análisis , Gonadotropina Coriónica Humana de Subunidad beta/análisis , Femenino , Humanos , Edad Materna , Hueso Nasal/anomalías , Hueso Nasal/embriología , Medida de Translucencia Nucal , Embarazo , Segundo Trimestre del Embarazo , Proteína Plasmática A Asociada al Embarazo/análisis , Flujo Sanguíneo Regional/fisiología , Estudios Retrospectivos , Insuficiencia de la Válvula Tricúspide/diagnóstico por imagen , Insuficiencia de la Válvula Tricúspide/fisiopatología , Ultrasonografía Prenatal , Venas Umbilicales/fisiopatología , Vena Cava Inferior/fisiopatología
9.
Ultraschall Med ; 32 Suppl 2: E108-14, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21877317

RESUMEN

PURPOSE: The purpose of this study was to compare the prenatal detection of four congenital heart defects (CHDs) and the image quality of five corresponding ultrasound planes among obese, overweight and normal-weight women. MATERIALS AND METHODS: This was a retrospective cohort study of 54,846 pregnancies undergoing fetal echocardiography between 18 and 37 weeks of gestation in the years from 2000 to 2007. The women were categorized according to pre-pregnancy body mass index (BMI) as normal-weight (BMI < 25), overweight (BMI 25 - 29.9) and obese (BMI ≥ 30). Image quality and prenatal detection of atrioventricular septal defect (AVSD), double outlet right ventricle (DORV), tetralogy of fallot (TOF) and dextro transposition of the great arteries (D-TGA) were evaluated in the BMI strata. RESULTS: 108 cases with one of the considered CHDs were identified. The prevalence was significantly higher (relative risk = 2.04) in overweight or obese women (57/19,404 vs. 51/35,442, p < 0.0002) than in normal-weight women. In total 86.1% of CHDs were correctly identified prenatally (93/108, CI: 79.6%-92.6%), 84.3% (43/51) in the normal weight group, 88.6% (39/44) in the overweight group and 84.6% (11/13) in the obese group. The rate of insufficient ultrasound images increased from 6.4% in normal-weight patients to 17.4% in obese women within the 108 CHD cases. CONCLUSION: The prenatal detection of fetal AVSD, DORV, TOF and D-TGA was also satisfactory in overweight and obese patients, but image quality substantially decreases with an increasing maternal BMI. If there is a BMI-associated difference in the detection rate, it probably will not exceed 20%.


Asunto(s)
Ecocardiografía/métodos , Cardiopatías Congénitas/diagnóstico por imagen , Aumento de la Imagen , Obesidad/diagnóstico por imagen , Obesidad/fisiopatología , Sobrepeso/diagnóstico por imagen , Sobrepeso/fisiopatología , Complicaciones del Embarazo/diagnóstico por imagen , Complicaciones del Embarazo/fisiopatología , Ultrasonografía Prenatal/métodos , Adulto , Índice de Masa Corporal , Estudios de Cohortes , Ventrículo Derecho con Doble Salida/diagnóstico por imagen , Femenino , Defectos de los Tabiques Cardíacos/diagnóstico por imagen , Humanos , Embarazo , Estudios Retrospectivos , Sensibilidad y Especificidad , Tetralogía de Fallot/diagnóstico por imagen , Transposición de los Grandes Vasos/diagnóstico por imagen
10.
J Exp Med ; 178(5): 1607-16, 1993 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-8228809

RESUMEN

We have previously produced lines of rats transgenic for HLA-B27 and human beta 2-microglobulin (h beta 2m) that develop a progressive inflammatory disease sharing many clinical and histologic features with the B27-associated human spondyloarthropathies, including gut and male genital inflammation, arthritis, and psoriasiform skin lesions. Other transgenic lines that express lower levels of B27 and h beta 2m remain healthy. To investigate the cellular basis for the multisystem inflammatory disease in these rats, we transferred lymphoid cell populations from disease-prone transgenic lines to irradiated disease-resistant transgenic and nontransgenic recipients. In recipients of cells from two different disease-prone lines, successful transfer required engraftment of bone marrow cells. Transfer of disease with fetal liver cells suggested that neither mature effector cells nor active disease in the donors was necessary for induction of disease in the recipients. Remission of the spontaneous disease in irradiated transgenic rats was induced by engraftment of nontransgenic bone marrow. These results suggest that the expression of HLA-B27 in bone marrow-derived cells alone is sufficient for the development of B27-associated disease, and that disease transfer requires engraftment of a bone marrow precursor cell for which mature cells in spleen or in lymph node cannot substitute.


Asunto(s)
Trasplante de Médula Ósea , Antígeno HLA-B27/genética , Inflamación/genética , Microglobulina beta-2/genética , Animales , Animales Modificados Genéticamente , Médula Ósea/inmunología , Médula Ósea/patología , Trasplante de Médula Ósea/inmunología , Citometría de Flujo , Antígeno HLA-B27/biosíntesis , Humanos , Inflamación/inmunología , Inflamación/patología , Complejo Mayor de Histocompatibilidad , Masculino , Ratas , Ratas Endogámicas Lew , Bazo/inmunología , Microglobulina beta-2/biosíntesis
11.
J Exp Med ; 180(6): 2359-64, 1994 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-7964509

RESUMEN

A number of inflammatory disease states occur with greatly increased frequency in individuals inheriting the human major histocompatibility complex class I allele HLA-B27. In a minority of cases, namely those with B27-associated reactive arthritis, there is good evidence that the disease state is triggered by infection with an enteric or genitourinary bacterial pathogen. For the majority of B27-associated disease, no definite pathogenetic role for bacteria has been established. However, in these latter cases intestinal inflammation can often be demonstrated, and it sometimes occupies a major part of the clinical picture. Rats transgenic for B27 are known to develop a disorder resembling B27-associated human disease, with prominent intestinal, joint, skin, and male genital inflammatory lesions. We report here that B27 transgenic rats raised in a germfree environment do not develop inflammatory intestinal or peripheral joint disease, whereas the skin and genital inflammatory lesions are unaffected by the germfree state. These findings support the concept that gut and joint inflammation are pathogenetically closely related, and they provide direct evidence that the commensal gut flora play an important role in the pathogenesis of B27-associated gut and joint inflammation.


Asunto(s)
Vida Libre de Gérmenes , Antígeno HLA-B27/biosíntesis , Inflamación/prevención & control , Enfermedades Intestinales/prevención & control , Artropatías/prevención & control , Animales , Animales Modificados Genéticamente , Northern Blotting , Colon/inmunología , Colon/patología , Antígeno HLA-B27/genética , Humanos , Inflamación/inmunología , Enfermedades Intestinales/inmunología , Artropatías/inmunología , Hígado/metabolismo , Masculino , Orosomucoide/biosíntesis , ARN Mensajero/análisis , Ratas , Ratas Endogámicas F344 , Ratas Endogámicas Lew , Piel/inmunología , Piel/patología , Microglobulina beta-2/biosíntesis
12.
J Exp Med ; 188(5): 877-86, 1998 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-9730889

RESUMEN

Human histocompatibility leukocyte antigen B27 is highly associated with the rheumatic diseases termed spondyloarthropathies, but the mechanism is not known. B27 transgenic rats develop a spontaneous disease resembling the human spondyloarthropathies that includes arthritis and colitis. To investigate whether this disease requires the binding of specific peptides to B27, we made a minigene construct in which a peptide from influenza nucleoprotein, NP383-391 (SRYWAIRTR), which binds B27 with high affinity, is targeted directly to the ER by the signal peptide of the adenovirus E3/gp19 protein. Rats transgenic for this minigene, NP1, were made and bred with B27 rats. The production of the NP383-391 peptide in B27(+)NP1(+) rats was confirmed immunologically and by mass spectrometry. The NP1 product displaced approximately 90% of the 3H-Arg-labeled endogenous peptide fraction in B27(+)NP1(+) spleen cells. Male B27(+)NP1(+) rats had a significantly reduced prevalence of arthritis, compared with B27(+)NP- males or B27(+) males with a control construct, NP2, whereas colitis was not significantly affected by the NP1 transgene. These findings support the hypothesis that B27-related arthritis requires binding of a specific peptide or set of peptides to B27, and they demonstrate a method for efficient transgenic targeting of peptides to the ER.


Asunto(s)
Artritis/genética , Artritis/inmunología , Antígeno HLA-B27/genética , Antígeno HLA-B27/metabolismo , Fragmentos de Péptidos/inmunología , Fragmentos de Péptidos/metabolismo , Proteínas de Unión al ARN , Secuencia de Aminoácidos , Animales , Animales Modificados Genéticamente , Artritis/epidemiología , Secuencia de Bases , Cromatografía Líquida de Alta Presión , Citotoxicidad Inmunológica/genética , Femenino , Regulación de la Expresión Génica/inmunología , Humanos , Virus de la Influenza A/genética , Masculino , Espectrometría de Masas , Datos de Secuencia Molecular , Proteínas de la Nucleocápside , Nucleoproteínas/biosíntesis , Nucleoproteínas/genética , Nucleoproteínas/inmunología , Fragmentos de Péptidos/genética , Prevalencia , Unión Proteica/genética , Unión Proteica/inmunología , Ratas , Ratas Endogámicas Lew , Ratas Sprague-Dawley , Linfocitos T Citotóxicos/inmunología , Transgenes/inmunología , Proteínas del Núcleo Viral/biosíntesis , Proteínas del Núcleo Viral/genética , Proteínas del Núcleo Viral/inmunología
13.
J Cell Biol ; 111(2): 347-59, 1990 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-2199454

RESUMEN

The distribution of human low density lipoprotein (LDL) receptors was studied by immunofluorescence and immunoelectron microscopy in epithelial cells of transgenic mice that express high levels of receptors under control of the metallothionein-I promoter. In hepatocytes and intestinal epithelial cells, the receptors were confined to the basal and basolateral surfaces, respectively. Very few LDL receptors were present in coated pits or intracellular vesicles. In striking contrast, in the epithelium of the renal tubule the receptors were present on the apical (lumenal) surface where they appeared to be concentrated at the base of microvilli and were abundant in vesicles of the endocytic recycling pathway. Intravenously administered LDL colloidal gold conjugates bound to the receptors on hepatocyte microvilli and were slowly internalized, apparently through slow migration into coated pits. We conclude that (a) sorting of LDL receptors to the surface of different epithelial cells varies with each tissue; and (b) in addition to a signal for clustering in coated pits, the LDL receptor may contain a signal for retention in noncoated membrane that is manifest in hepatocytes and intestinal epithelial cells, but not in renal epithelial cells or cultured human fibroblasts.


Asunto(s)
Receptores de LDL/genética , Animales , Epitelio/metabolismo , Epitelio/ultraestructura , Técnica del Anticuerpo Fluorescente , Humanos , Yeyuno/metabolismo , Yeyuno/ultraestructura , Riñón/metabolismo , Riñón/ultraestructura , Lipoproteínas LDL/metabolismo , Hígado/metabolismo , Hígado/ultraestructura , Metalotioneína/genética , Ratones , Ratones Transgénicos , Músculo Liso/metabolismo , Músculo Liso/ultraestructura , Plásmidos , Regiones Promotoras Genéticas , Receptores de LDL/análisis , Receptores de LDL/ultraestructura , Transcripción Genética
14.
J Cell Biol ; 117(1): 39-46, 1992 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1556156

RESUMEN

When expressed in livers of transgenic mice, the human low density lipoprotein (LDL) receptor is specifically targeted to the basolateral (sinusoidal) surface of hepatocytes as determined by immunofluorescence and immunoelectron microscopy. The COOH-terminal cytoplasmic domain of the receptor (residues 790-839) contains a signal for this targeting. A mutant receptor truncated at residue 812 was localized exclusively to the apical (bile canalicular) surface. A mutant receptor terminating at residue 829 showed the normal basolateral distribution, as did a receptor in which alanine was substituted for serine 833, which was previously shown to be a site for phosphorylation in vitro. These data localize the basolateral targeting signal to the 17-residue segment between residues 812 and 828. A 10-amino acid stretch within this segment shows a 4/10 match with a sequence within a previously identified basolateral sorting motif for the receptor for polymeric IgA/IgM in MDCK cells. The four shared residues are spaced at intervals of three, raising the possibility that they all face the same side of an alpha-helix. We conclude that this 10-amino acid stretch may contain a signal that directs certain proteins, including the LDL receptor and the polymeric IgG/IgM receptor, to the basolateral surface of polarized epithelia.


Asunto(s)
Membrana Celular/metabolismo , Hígado/metabolismo , Receptores de LDL/metabolismo , Secuencia de Aminoácidos , Animales , Membrana Celular/ultraestructura , Citoplasma/metabolismo , Femenino , Técnica del Anticuerpo Fluorescente , Humanos , Cinética , Lipoproteínas/metabolismo , Hígado/citología , Hígado/ultraestructura , Metionina/genética , Ratones , Ratones Transgénicos , Microscopía Inmunoelectrónica , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Regiones Promotoras Genéticas , Señales de Clasificación de Proteína/análisis , Señales de Clasificación de Proteína/metabolismo , Receptores de LDL/análisis , Receptores de LDL/genética , Homología de Secuencia de Ácido Nucleico
15.
Science ; 250(4985): 1273-5, 1990 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-2244210

RESUMEN

The current studies were designed to determine whether chronic overexpression of low density lipoprotein (LDL) receptors in the liver would protect mice from the increase in plasma LDL-cholesterol that is induced by high-fat diets. A line of transgenic mice was studied that express the human LDL receptor gene in the liver under control of the transferrin promoter. When fed a diet containing cholesterol, saturated fat, and bile acids for 3 weeks, the transgenic mice, in contrast to normal mice, did not develop a detectable increase in plasma LDL. The current data indicate that unregulated overexpression of LDL receptors can protect against diet-induced hypercholesterolemia in mice.


Asunto(s)
LDL-Colesterol/sangre , Grasas de la Dieta/efectos adversos , Expresión Génica , Hipercolesterolemia/prevención & control , Receptores de LDL/genética , Animales , Colesterol en la Dieta/efectos adversos , Exones , Humanos , Hipercolesterolemia/etiología , Intrones , Lipoproteínas/sangre , Lipoproteínas HDL/sangre , Lipoproteínas IDL , Lipoproteínas VLDL/sangre , Hígado/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Hibridación de Ácido Nucleico , Regiones Promotoras Genéticas/genética , ARN Mensajero/genética , Transferrina/genética
16.
Science ; 235(4784): 53-8, 1987 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-2432657

RESUMEN

The 5' flanking region of the mouse alpha-fetoprotein (AFP) gene contains a tissue-specific promoter and three upstream regulatory elements that behave as classical enhancers. At least one of these enhancers is now shown to be required for the tissue-specific expression of the AFP gene when it is introduced into the mouse genome by microinjection of cloned DNA fragments into fertilized eggs. Each enhancer can direct expression in the appropriate tissues, the visceral endoderm of the yolk sac, the fetal liver, and the gastrointestinal tract, but each exerts different influence in these three tissues. These differences may explain the tissue-specific diversity in the levels of expression characteristic of the AFP gene. The postnatal repression of transcription of the AFP gene in both liver and gut, as well as the reinitiation of its transcription during liver regeneration, is mimicked by the introduced gene when it is linked to the enhancer domains together or singly. Thus, the DNA sequence elements responsible for directing the activation of AFP transcription, its repression, and reinduction are contained in a limited segment of DNA within or 5' to the gene (or both) and are operative in the absence of the closely linked albumin gene.


Asunto(s)
Elementos de Facilitación Genéticos , Genes Reguladores , alfa-Fetoproteínas/genética , Animales , Clonación Molecular , Regulación de la Expresión Génica , Genes , Intestinos/fisiología , Hígado/fisiología , Ratones , Regiones Promotoras Genéticas , ARN Mensajero/genética , Distribución Tisular , Transcripción Genética , Transfección , Saco Vitelino/fisiología
17.
Science ; 222(4625): 809-14, 1983 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-6356363

RESUMEN

The promoter or regulatory region of the mouse gene for metallothionein-I was fused to the structural gene coding for human growth hormone. These fusion genes were introduced into mice by microinjection of fertilized eggs. Twenty-three (70 percent) of the mice that stably incorporated the fusion genes showed high concentrations of human growth hormone in their serum and grew significantly larger than control mice. Synthesis of human growth hormone was induced further by cadmium or zinc, which normally induce metallothionein gene expression. Transgenic mice that expressed human growth hormone also showed increased concentrations of insulin-like growth factor I in their serum. Histology of their pituitaries suggests dysfunction of the cells that normally synthesize growth hormone. The fusion genes were expressed in all tissues examined, but the ratio of human growth hormone messenger RNA to endogenous metallothionein-I messenger RNA varied among different tissues and different animals, suggesting that expression of the foreign genes is influenced by site of integration and tissue environment.


Asunto(s)
Hormona del Crecimiento/genética , Metalotioneína/genética , Ratones/crecimiento & desarrollo , Animales , Cadmio/farmacología , ADN Recombinante , Regulación de la Expresión Génica/efectos de los fármacos , Ingeniería Genética , Operón , ARN Mensajero/genética , Distribución Tisular , Transcripción Genética , Zinc/farmacología
18.
Science ; 238(4824): 188-93, 1987 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-2821617

RESUMEN

Three lines of transgenic mice were produced that develop pancreatic neoplasms as a consequence of expression of an elastase I-SV40 T-antigen fusion gene in the acinar cells. A developmental analysis suggests at least a two-stage process in the ontogeny of this disease. The first stage is a T antigen-induced, preneoplastic state characterized by a progression from hyperplasia to dysplasia of the exocrine pancreas, by an increased percentage of tetraploid cells, and by an arrest in acinar cell differentiation. The second stage is characterized by the formation of tumor nodules that appear to be monoclonal, because they have discrete aneuploid DNA contents. The cells within the nodules as compared to normal pancreatic tissue have less total RNA by a factor of 5, less pancreas-specific messenger RNA by a factor of about 50, and increased levels of T-antigen messenger RNA. A tumor cell line has been derived that retains both pancreatic and neoplastic properties.


Asunto(s)
Antígenos Transformadores de Poliomavirus/genética , Transformación Celular Neoplásica , Neoplasias Pancreáticas/microbiología , Proteínas Quinasas/genética , Virus 40 de los Simios/genética , Animales , Enzimas de Restricción del ADN , Genes , Genes Virales , Ratones , Ratones Transgénicos , Elastasa Pancreática/genética , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patología , ARN Mensajero/genética
19.
Science ; 239(4845): 1277-81, 1988 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-3344433

RESUMEN

A complementary DNA encoding the human low density lipoprotein (LDL) receptor under control of the mouse metallothionein-I promoter was injected into fertilized mouse eggs, and a strain of mice expressing high levels of LDL receptors was established. After administration of cadmium, these mice cleared intravenously injected 125I-labeled LDL from blood eight to ten times more rapidly than did normal mice. The plasma concentrations of apoproteins B-100 and E, the two ligands for the LDL receptor, declined by more than 90 percent after cadmium treatment, but the concentration of another apoprotein, A-I, was unaffected. Therefore, overexpression of an endocytotic receptor can dramatically lower the ambient concentration of its ligand in vivo.


Asunto(s)
Genes , Lipoproteínas LDL/sangre , Receptores de LDL/genética , Animales , Clonación Molecular , ADN/genética , Femenino , Humanos , Cinética , Ratones , Ratones Transgénicos , Plásmidos , Receptores de LDL/metabolismo , Valores de Referencia , Transcripción Genética
20.
Science ; 293(5537): 2084-7, 2001 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-11557891

RESUMEN

Transcription factor TFIID, composed of TBP and TAFII subunits, is a central component of the RNA polymerase II machinery. Here, we report that the tissue-selective TAFII105 subunit of TFIID is essential for proper development and function of the mouse ovary. Female mice lacking TAFII105 are viable but infertile because of a defect in folliculogenesis correlating with restricted expression of TAFII105 in the granulosa cells of the ovarian follicle. Gene expression profiling has uncovered a defective inhibin-activin signaling pathway in TAFII105-deficient ovaries. Together, these studies suggest that TAFII105 mediates the transcription of a subset of genes required for proper folliculogenesis in the ovary and establishes TAFII105 as a cell type-specific component of the mammalian transcriptional machinery.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Células de la Granulosa/fisiología , Folículo Ovárico/crecimiento & desarrollo , Ovario/fisiología , Factores Asociados con la Proteína de Unión a TATA , Factores de Transcripción/metabolismo , Transcripción Genética , Animales , Proteínas de Unión al ADN/genética , Regulación hacia Abajo , Femenino , Perfilación de la Expresión Génica , Regulación del Desarrollo de la Expresión Génica , Células de la Granulosa/metabolismo , Hibridación in Situ , Infertilidad Femenina , Masculino , Ratones , Ratones Noqueados , Análisis de Secuencia por Matrices de Oligonucleótidos , Tamaño de los Órganos , Especificidad de Órganos , Ovario/citología , Ovario/crecimiento & desarrollo , Ovario/metabolismo , Ovulación , Subunidades de Proteína , Transducción de Señal , Factor de Transcripción TFIID , Factores de Transcripción/genética , Factores de Transcripción TFII/metabolismo
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