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1.
Cereb Cortex ; 30(2): 587-596, 2020 03 21.
Artículo en Inglés | MEDLINE | ID: mdl-31216015

RESUMEN

Turner syndrome (TS) is a genetic disorder affecting approximately 1:2000 live-born females. It results from partial or complete X monosomy and is associated with a range of clinical issues including a unique cognitive profile and increased risk for certain behavioral problems. Structural neuroimaging studies in adolescents, adults, and older children with TS have revealed altered neuroanatomy but are unable to identify when in development differences arise. In addition, older children and adults have often been exposed to years of growth hormone and/or exogenous estrogen therapy with potential implications for neurodevelopment. The study presented here is the first to test whether brain structure is altered in infants with TS. Twenty-six infants with TS received high-resolution structural MRI scans of the brain at 1 year of age and were compared to 47 typically developing female and 39 typically developing male infants. Results indicate that the typical neuroanatomical profile seen in older individuals with TS, characterized by decreased gray matter volumes in premotor, somatosensory, and parietal-occipital cortex, is already present at 1 year of age, suggesting a stable phenotype with origins in the prenatal or early postnatal period.


Asunto(s)
Encéfalo/patología , Síndrome de Turner/patología , Encéfalo/diagnóstico por imagen , Femenino , Humanos , Lactante , Imagen por Resonancia Magnética , Tamaño de los Órganos , Síndrome de Turner/diagnóstico por imagen
2.
Nature ; 505(7485): 654-6, 2014 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-24476888

RESUMEN

Brown dwarfs--substellar bodies more massive than planets but not massive enough to initiate the sustained hydrogen fusion that powers self-luminous stars--are born hot and slowly cool as they age. As they cool below about 2,300 kelvin, liquid or crystalline particles composed of calcium aluminates, silicates and iron condense into atmospheric 'dust', which disappears at still cooler temperatures (around 1,300 kelvin). Models to explain this dust dispersal include both an abrupt sinking of the entire cloud deck into the deep, unobservable atmosphere and breakup of the cloud into scattered patches (as seen on Jupiter and Saturn). However, hitherto observations of brown dwarfs have been limited to globally integrated measurements, which can reveal surface inhomogeneities but cannot unambiguously resolve surface features. Here we report a two-dimensional map of a brown dwarf's surface that allows identification of large-scale bright and dark features, indicative of patchy clouds. Monitoring suggests that the characteristic timescale for the evolution of global weather patterns is approximately one day.

3.
Haemophilia ; 22(4): 507-13, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26936227

RESUMEN

BACKGROUND: The paradigm(™) 2 and 4 phase 3 clinical trials investigated the safety and efficacy of nonacog beta pegol, a recombinant glycoPEGylated factor IX (FIX) with extended half-life, in previously treated haemophilia B patients. AIM: These post hoc analyses investigated the bleeding patterns in target joints. METHODS: Patients randomized to 40 or 10 IU kg(-1) once weekly prophylaxis who had at least one target joint were included. Baseline demographics and disease-specific data were collected. Bleeding patterns were assessed, and an International Society on Thrombosis and Haemostasis (ISTH) definition of target joints was used. RESULTS: A total of 67% and 8% of patients in the 40 and 10 IU kg(-1) arm, respectively, did not experience target joint bleeds during the paradigm(™) 2 trial. Twenty-four target joints were recorded in each prophylaxis arm at baseline. During the paradigm(™) 2 trial, no bleeds were reported in 17 (71%) and 7 (29%) target joints in the 40 and 10 IU kg(-1) arms respectively. All target joint bleeds in the 40 IU kg(-1) once weekly prophylaxis arm were controlled with a single injection of 40 IU kg(-1) nonacog beta pegol. By the latest ISTH definition, 90% and 58% of target joints in the 40 and 10 IU kg(-1) arms, respectively, were no longer considered target joints at the end of the paradigm(™) 2 trial. At the end of the paradigm(™) 4 extension trial, all target joints in the 40 IU kg(-1) arm were no longer considered target joints. CONCLUSION: Routine prophylaxis with 40 IU kg(-1) once weekly nonacog beta pegol has the potential for effective management of target joint bleeds in haemophilia B patients.


Asunto(s)
Coagulantes/uso terapéutico , Factor IX/uso terapéutico , Hemofilia B/tratamiento farmacológico , Artropatías/fisiopatología , Polietilenglicoles/uso terapéutico , Adolescente , Adulto , Niño , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Semivida , Hemorragia/prevención & control , Humanos , Artropatías/epidemiología , Masculino , Persona de Mediana Edad , Proteínas Recombinantes/uso terapéutico , Resultado del Tratamiento , Adulto Joven
4.
Evol Comput ; 23(3): 451-79, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25781724

RESUMEN

The parameter-less population pyramid (P3) is a recently introduced method for performing evolutionary optimization without requiring any user-specified parameters. P3's primary innovation is to replace the generational model with a pyramid of multiple populations that are iteratively created and expanded. In combination with local search and advanced crossover, P3 scales to problem difficulty, exploiting previously learned information before adding more diversity. Across seven problems, each tested using on average 18 problem sizes, P3 outperformed all five advanced comparison algorithms. This improvement includes requiring fewer evaluations to find the global optimum and better fitness when using the same number of evaluations. Using both algorithm analysis and comparison, we find P3's effectiveness is due to its ability to properly maintain, add, and exploit diversity. Unlike the best comparison algorithms, P3 was able to achieve this quality without any problem-specific tuning. Thus, unlike previous parameter-less methods, P3 does not sacrifice quality for applicability. Therefore we conclude that P3 is an efficient, general, parameter-less approach to black box optimization which is more effective than existing state-of-the-art techniques.


Asunto(s)
Algoritmos , Modelos Teóricos , Teorema de Bayes , Ligamiento Genético
5.
Nat Genet ; 23(1): 52-7, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10471498

RESUMEN

Cystinuria (MIM 220100) is a common recessive disorder of renal reabsorption of cystine and dibasic amino acids. Mutations in SLC3A1, encoding rBAT, cause cystinuria type I (ref. 1), but not other types of cystinuria (ref. 2). A gene whose mutation causes non-type I cystinuria has been mapped by linkage analysis to 19q12-13.1 (Refs 3,4). We have identified a new transcript, encoding a protein (bo, +AT, for bo,+ amino acid transporter) belonging to a family of light subunits of amino acid transporters, expressed in kidney, liver, small intestine and placenta, and localized its gene (SLC7A9) to the non-type I cystinuria 19q locus. Co-transfection of bo,+AT and rBAT brings the latter to the plasma membrane, and results in the uptake of L-arginine in COS cells. We have found SLC7A9 mutations in Libyan-Jews, North American, Italian and Spanish non-type I cystinuria patients. The Libyan Jewish patients are homozygous for a founder missense mutation (V170M) that abolishes b o,+AT amino-acid uptake activity when co-transfected with rBAT in COS cells. We identified four missense mutations (G105R, A182T, G195R and G295R) and two frameshift (520insT and 596delTG) mutations in other patients. Our data establish that mutations in SLC7A9 cause non-type I cystinuria, and suggest that bo,+AT is the light subunit of rBAT.


Asunto(s)
Sistemas de Transporte de Aminoácidos Básicos , Proteínas Portadoras/genética , Cistinuria/genética , Mutación del Sistema de Lectura , Glicoproteínas de Membrana/genética , Mutación Missense , Secuencia de Aminoácidos , Animales , Células COS , Cromosomas Humanos Par 19 , Cistinuria/etnología , ADN Complementario/análisis , Femenino , Humanos , Italia , Judíos , Libia , Masculino , Modelos Biológicos , Datos de Secuencia Molecular , América del Norte , Linaje , Homología de Secuencia de Aminoácido , España , Distribución Tisular
6.
Respiration ; 84(4): 306-11, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22846608

RESUMEN

BACKGROUND: The forced vital capacity (FVC) is an established measure in amyotrophic lateral sclerosis (ALS) clinical trials. Recently the sniff nasal inspiratory pressure (SNIP) test has been increasingly used as a respiratory measure. OBJECTIVES: It was the aim of this study to assess the feasibility of SNIP as an outcome measure in a phase III clinical trial with a lead-in design. METHODS: Twenty patients were enrolled in a randomized clinical trial. FVC, SNIP in sitting (SNIPsitt) and supine (SNIPsup) positions, and the ALS functional rating scale score (ALSFRS-R) were measured every 4 weeks. RESULTS: Complete data were available for 19 patients over 5 months. Baseline values were normal for FVC (101 ± 14%) but abnormal for SNIPsitt and SNIPsup (84 ± 34% and 82 ± 33%). While FVC and ALSFRS-R declined in parallel, SNIPsitt measures declined significantly less compared to ALSFRS-R (p < 0.05) and FVC (p < 0.001) up to 4 months after enrollment. Over 50% of patients still had values equal to or above baseline SNIPsitt measures after 3 months despite abnormal baseline values. CONCLUSIONS: The delayed decline in SNIP measurements suggests a learning effect over time. The optimal number of SNIPs in ALS clinical trials has yet to be determined. SNIP measures should be used with caution in trials with a lead-in design.


Asunto(s)
Esclerosis Amiotrófica Lateral/fisiopatología , Inhalación , Nariz/fisiopatología , Presión , Adulto , Anciano , Estudios de Factibilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud , Postura , Capacidad Vital
7.
Ann Oncol ; 22(12): 2610-2615, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21415234

RESUMEN

BACKGROUND: Lapatinib (GW572016) is a dual tyrosine kinase inhibitor of epidermal growth factor receptor (EGFR) and human epidermal growth factor receptor 2 (HER2/ErbB2), which are reported as overexpressed in 15%-45% of gastric cancers, making them potential targets. PATIENTS AND METHODS: The primary objective of this study was to assess response rate. Secondary objectives included overall survival (OS), toxicity, and the relationship of EGFR, ErbB2, and markers of angiogenesis with clinical outcome. Lapatinib was administered to chemonaive metastatic gastric cancer patients at a dose of 1500 mg orally daily for 28 days. RESULTS: The study enrolled 47 patients from February 2005 until May 2006. Four patients (9%) had a confirmed partial response (PR), 1 (2%) had an unconfirmed PR, and 10 (23%) had stable disease. Median (95% confidence interval) time to treatment failure was 1.9 (1.6-3.1) months and OS was 4.8 (3.2-7.4) months. Significant adverse events: one grade 4 cardiac ischemia/infarction, one grade 4 fatigue, and one grade 4 emesis. One treatment-related death was due to central nervous system ischemia. An exploratory analysis of markers revealed gene expression of HER2, interleukin (IL)-8 and genomic polymorphisms IL-8, and vascular endothelial growth factor correlated with OS. CONCLUSIONS: Lapatinib is well tolerated, with modest single-agent activity in advanced/metastatic gastric cancer patients. Potential molecular correlatives were identified which warrant further validation.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Antineoplásicos/uso terapéutico , Biomarcadores de Tumor/genética , Quinazolinas/uso terapéutico , Neoplasias Gástricas/tratamiento farmacológico , Adenocarcinoma/genética , Adenocarcinoma/mortalidad , Adenocarcinoma/secundario , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/metabolismo , Femenino , Expresión Génica , Humanos , Estimación de Kaplan-Meier , Lapatinib , Masculino , Persona de Mediana Edad , Polimorfismo Genético , Neoplasias Gástricas/genética , Neoplasias Gástricas/mortalidad , Neoplasias Gástricas/patología , Resultado del Tratamiento
8.
Vet Pathol ; 48(4): 896-902, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20724516

RESUMEN

Damaraland mole rats (Cryptomys damarensis) are among the longest-living rodents, with a maximum longevity of approximately 16 years. As one of the few mammals termed eusocial, these animals have been used in behavioral, genetic, metabolic, and physiologic research at the University of Connecticut since 1997. For individual identification at 3 to 4 months of age, mole rats were subcutaneously implanted with microchip transponders (11 mm in length) in the dorsal cervical region. In 2007, 2 of the 90 implanted adults, 10-year-old and 9-year-old females, developed subcutaneous masses at the site of the implant. Histopathological and immunohistochemical examinations revealed amelanotic melanoma and fibrosarcoma, respectively, with metastasis of the amelanotic melanoma. In 2008, a total of 3 adult males were castrated as part of a sex behavior study; 3 months later, all 3 castrated males developed subcutaneous masses around their implants, whereas none of the noncastrated males had masses. After an additional 9 months, these masses were found to be granulomas. To the authors' knowledge, this is the first report of neoplasia in this species. Both the tumors and the granulomas surrounded the microchip transponder.


Asunto(s)
Sistemas de Identificación Animal/veterinaria , Granuloma/veterinaria , Ratas Topo , Neoplasias/veterinaria , Prótesis e Implantes/efectos adversos , Enfermedades de los Roedores/etiología , Sistemas de Identificación Animal/instrumentación , Animales , Femenino , Granuloma/etiología , Granuloma/patología , Masculino , Neoplasias/etiología , Neoplasias/patología , Enfermedades de los Roedores/patología
9.
Ann Oncol ; 21(6): 1196-1202, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19875761

RESUMEN

BACKGROUND: The purpose was to examine the prognostic impact of features of tumor cells and immune microenvironment in patients with follicular lymphoma treated with and without anti-CD20 monoclonal antibody therapy. PATIENTS AND METHODS: Tissue microarrays were constructed from archived tissue obtained from patients on three sequential Southwest Oncology Group (SWOG) trials for FL. All three trials included anthracycline-based chemotherapy. Anti-CD20 monoclonal antibodies were included for patients in the latter two trials. Immunohistochemistry was used to study the number and distribution of cells staining for forkhead box protein P3 (FOXP3) and lymphoma-associated macrophages (LAMs) and the number of lymphoma cells staining for myeloma-associated antigen-1 (MUM-1). Cox proportional hazards regression was used to evaluate the association between marker expression and overall survival (OS). RESULTS: The number or pattern of infiltrating FOXP3 cells and LAMs did not correlate with OS in sequential SWOG studies for FL. The presence of MUM-1 correlated with lower OS for patients who received monoclonal antibody but not for those treated with chemotherapy alone. CONCLUSIONS: Immune cell composition of lymph nodes did not correlate with OS in this analysis of trials in FL. The mechanism of the observed correlation between MUM-1 expression and adverse prognosis in patients receiving monoclonal antibody therapy requires confirmation.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Factores Reguladores del Interferón/metabolismo , Linfoma Folicular/diagnóstico , Linfoma Folicular/terapia , Macrófagos/patología , Linfocitos T Reguladores/patología , Adulto , Anciano , Recuento de Células Sanguíneas , Ensayos Clínicos Fase II como Asunto , Terapia Combinada , Femenino , Humanos , Inmunoterapia/métodos , Linfoma Folicular/inmunología , Linfoma Folicular/metabolismo , Macrófagos/metabolismo , Masculino , Oncología Médica/métodos , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico , Ensayos Clínicos Controlados Aleatorios como Asunto , Sudoeste de Estados Unidos , Linfocitos T Reguladores/efectos de los fármacos , Linfocitos T Reguladores/metabolismo
10.
J Neurol Neurosurg Psychiatry ; 81(10): 1135-40, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20498181

RESUMEN

BACKGROUND: Many patients with amyotrophic lateral sclerosis (ALS) experience cramps during the course of the disease but so far, none of the medications used has been of proven benefit. The objective was to determine the effect of orally administered tetrahydrocannabinol (THC) on cramps in ALS patients. METHODS: The authors conducted a randomised, double-blind, placebo-controlled crossover trial in 27 ALS patients suffering from moderate to severe (visual analogue scale (VAS); VAS≥4) daily cramps. There were 7 women and 20 men with a mean age of 57 years and a mean functional ALS score (ALSFRS-R) of 38.4. Patients were randomly assigned to receive 5 mg THC twice daily followed by placebo or vice versa. Each treatment period lasted for 2 weeks and was preceded by a 2-week drug-free observation period (run-in, wash-out period respectively). The primary outcome measure was change in cramp intensity as assessed by a VAS. Secondary outcome measures included the number of cramps per day, number of cramps during daytime and bedtime, intensity of fasciculations (VAS) as well as validated measures of quality of life (ALSAQ-40), quality of sleep (SDQ), appetite (FAACT) and depression (HADS). RESULTS: Complete data were available from 22 patients. THC was well tolerated. There was no evidence for a treatment effect on cramp intensity, number of cramps, fasciculation intensity or any of the other secondary outcome measures. CONCLUSIONS: This interventional study with orally administered THC 5 mg twice daily did not demonstrate subjective improvement of cramp intensity in ALS patients.


Asunto(s)
Esclerosis Amiotrófica Lateral/tratamiento farmacológico , Dronabinol/uso terapéutico , Calambre Muscular/tratamiento farmacológico , Adulto , Anciano , Esclerosis Amiotrófica Lateral/complicaciones , Apetito/efectos de los fármacos , Estudios Cruzados , Depresión/tratamiento farmacológico , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Calambre Muscular/complicaciones , Calidad de Vida , Índice de Severidad de la Enfermedad , Trastornos del Sueño-Vigilia/complicaciones , Trastornos del Sueño-Vigilia/tratamiento farmacológico
11.
J Cell Biol ; 90(1): 236-42, 1981 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-6454695

RESUMEN

A membrane-integrated , core-glycosylated form of bovine opsin was synthesized in vitro when bovine retina mRNA was translated in a wheat germ cell-free system supplemented with dog pancreas microsomal vesicles; glycosylation and integration of opsin into membranes were coupled to translation. Proteolysis with themolysin was used to probe the orientation of opsin within the dog pancreas microsomal membrane, and to compare it with that of opsin in rod cell disk membranes isolated from bovine retina. Intact microsomal or disk vesicles were required for production of discrete, membrane-associated thermolysin fragments of opsin; no discrete opsin fragments were detected when membranes were incubated with thermolysin in the presence of the nonionic detergent, Triton X-100. The major opsin fragments produced by themosylin treatment of intact microsomal vesicles resembled those from disk vesicles in their size, oligosaccharide content, and order of appearance. In each case, the first cleavage of opsin took place at the COOH-terminus, generating a glycosylated fragment, O', which was only slightly smaller than intact opsin. Both the microsomal and disk membrane forms of O' were next cleaved internally; glycosylated fragments of similar sizes in both cases were detected which were derived from the NH(2)-terminal portion of O'. Several smaller NH(2)-terminal fragments of opsin were detected only in thermolysin-treated microsomal membranes, and not in disk membranes. The data suggest that the topology of opsin integrated into dog pancreas microsomal vesicles is similar to that in rod cell disk vesicles, although not identical. In each case, the glycosylated NH(2)-terminal region of opsin is located within the lumen of the vesicle, while discrete COOH-terminal and internal segments of opsin apparently emerge at the outer, cytoplasmic face of the membrane. Thus, opsin in the heterologous microsomal membrane, like its counterpart in the native disk membrane, may cross the bilayer at least three times. The internal domain of the polypeptide that emerges at the outer membrane surface is apparently more highly exposed in the case of opsin in microsomal membranes, evidenced by the additional internal thermolysin cleavage sites detected.


Asunto(s)
Proteínas del Ojo/metabolismo , Membranas Intracelulares/metabolismo , Pigmentos Retinianos/metabolismo , Animales , Metabolismo de los Hidratos de Carbono , Bovinos , Sistema Libre de Células , Perros , Retículo Endoplásmico/metabolismo , Proteínas del Ojo/análisis , Membranas Intracelulares/análisis , Microsomas/metabolismo , Biosíntesis de Proteínas , Pigmentos Retinianos/análisis , Segmento Externo de la Célula en Bastón/análisis , Opsinas de Bastones , Termolisina/farmacología
12.
J Cell Biol ; 108(3): 1067-78, 1989 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2522096

RESUMEN

A cell culture model for human cardiac myogenesis is introduced. Human fetal myocardial cells were dissociated enzymatically, and cultured in a mitogen-rich medium that promoted the growth of presumptive cardiac myoblasts. Strains of human cardiac myoblasts were generated from different anatomical regions of the fetal heart. The cells could be cultured for at least 30 generations, or frozen and recovered for later use. Differentiation was induced by culturing the cardiac myoblasts in a mitogen-poor medium. Differentiation of cardiac myoblasts was marked primarily by transcriptional activation of the atrial natriuretic factor (ANF) gene. Evidence is presented that posttranscriptional processing of ANF transcripts is affected by the anatomical origin of the cardiac myoblasts and the presence of cocultured neuronal cells. Cardiac myoblasts induced to differentiate in culture synthesized only low levels of sarcomeric myosin and cardiac alpha-actin, suggesting that differentiation of these cells progresses through two phases: an initial, noncontractile phase that is represented by the differentiating cultured cells; and a later contractile phase, in which myofibrillar assembly is accentuated and modulated by secondary signals from the cardiac milieu.


Asunto(s)
Corazón Fetal/citología , Miocardio/citología , Actinas/biosíntesis , Actinas/genética , Factor Natriurético Atrial/biosíntesis , Factor Natriurético Atrial/genética , Diferenciación Celular , División Celular , Células Cultivadas , Medios de Cultivo , Corazón Fetal/metabolismo , Regulación de la Expresión Génica , Atrios Cardíacos/citología , Atrios Cardíacos/embriología , Atrios Cardíacos/metabolismo , Ventrículos Cardíacos/citología , Ventrículos Cardíacos/embriología , Ventrículos Cardíacos/metabolismo , Histonas/biosíntesis , Histonas/genética , Humanos , Miocardio/metabolismo , Miosinas/biosíntesis , Miosinas/genética , Neuronas/fisiología , Procesamiento Postranscripcional del ARN , ARN Mensajero/genética , Transcripción Genética
13.
Science ; 223(4638): 833-5, 1984 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-6546454

RESUMEN

The suprachiasmatic nucleus has been identified tentatively as a circadian pacemaker. To examine the functional role of peptides found within suprachiasmatic neurons, avian pancreatic polypeptide and vasopressin were microinjected into the suprachiasmatic region. Avian pancreatic polypeptide, but not vasopressin, shifted the phase of the wheelrunning rhythm as a function of the time of its injection within the circadian cycle. Avian pancreatic polypeptide or a similar peptide may be one component of the neurochemical processes underlying entrainment to the light-dark cycle.


Asunto(s)
Ritmo Circadiano , Polipéptido Pancreático/farmacología , Núcleo Supraquiasmático/efectos de los fármacos , Animales , Aves , Ventrículos Cerebrales/efectos de los fármacos , Cricetinae , Actividad Motora/efectos de los fármacos , Proteínas del Tejido Nervioso/farmacología , Neuropéptido Y , Especificidad de la Especie , Vasopresinas/farmacología
14.
Science ; 198(4320): 953-5, 1977 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-563102

RESUMEN

Pinealectomized Syrian hamsters were injected thrice daily with 25 micrograms of melatonin per injection. The injections were administered at 3-hour intervals either during the day or during the night of a photoperiodic cycle of 14 hours of light and 10 hours of darkness. After 6 weeks of treatment with melatonin during the night, both pinealectomized and intact hamsters had reduced testis weight, and pinealectomized hamsters showed decreased levels of serum gonadotropins. Injection of melatonin during the day for 7 weeks either once (75 micrograms) a day or thrice (25 micrograms per injection) daily caused a reduction in testis weight in pinealectomized hamsters. Both pinealectomized and intact females injected with melatonin thrice daily during the day became anovulatory by week 7 of treatment. These results are similar to those observed when hamsters are exposed to a short photoperiod, suggesting that melatonin may be acting as a hormone in mediating the effects of photoperiod on the reproductive system of the Syrian hamster.


Asunto(s)
Estro/efectos de los fármacos , Melatonina/farmacología , Glándula Pineal/fisiología , Testículo/anatomía & histología , Animales , Cricetinae , Femenino , Hormona Folículo Estimulante/sangre , Luz , Hormona Luteinizante/sangre , Masculino , Mesocricetus , Tamaño de los Órganos/efectos de los fármacos , Embarazo , Factores de Tiempo
15.
Science ; 224(4648): 521-3, 1984 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-6538700

RESUMEN

Microinjection of arginine vasopressin into the medial preoptic area of the hypothalamus of male and female golden hamsters triggered a complex, stereotypic behavior--flank marking--a type of scent marking used in olfactory communication. The flank marking was not elicited by saline, oxytocin, neurotensin, or angiotensin II. Vasopressin was ineffective when injected into other areas of the hypothalamus or into the lateral cerebroventricle.


Asunto(s)
Arginina Vasopresina/farmacología , Área Preóptica/efectos de los fármacos , Conducta Estereotipada/efectos de los fármacos , Angiotensina II/farmacología , Animales , Castración , Ventrículos Cerebrales/efectos de los fármacos , Cricetinae , Femenino , Aseo Animal/efectos de los fármacos , Humanos , Hipotálamo/efectos de los fármacos , Hipotálamo Medio/efectos de los fármacos , Luz , Masculino , Mesocricetus , Microinyecciones , Neurotensina/farmacología , Oxitocina/farmacología
16.
Science ; 294(5550): 2323-8, 2001 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-11743194

RESUMEN

Agrobacterium tumefaciens is a plant pathogen capable of transferring a defined segment of DNA to a host plant, generating a gall tumor. Replacing the transferred tumor-inducing genes with exogenous DNA allows the introduction of any desired gene into the plant. Thus, A. tumefaciens has been critical for the development of modern plant genetics and agricultural biotechnology. Here we describe the genome of A. tumefaciens strain C58, which has an unusual structure consisting of one circular and one linear chromosome. We discuss genome architecture and evolution and additional genes potentially involved in virulence and metabolic parasitism of host plants.


Asunto(s)
Agrobacterium tumefaciens/genética , Genoma Bacteriano , Análisis de Secuencia de ADN , Agrobacterium tumefaciens/clasificación , Agrobacterium tumefaciens/patogenicidad , Agrobacterium tumefaciens/fisiología , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Proteínas Portadoras/química , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Ciclo Celular , Cromosomas Bacterianos/genética , Replicación del ADN , Genes Bacterianos , Datos de Secuencia Molecular , Filogenia , Tumores de Planta/microbiología , Plantas/microbiología , Plásmidos , Replicón , Rhizobiaceae/genética , Transducción de Señal , Sinorhizobium meliloti/genética , Sintenía , Telómero , Virulencia/genética
17.
Clin Nephrol ; 71(1): 59-62, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19203551

RESUMEN

Membranous glomerulonephritis and minimal change disease are the most common forms of glomerular diseases noted in patients with graft versus host disease after hematopoietic stem cell transplantation. Herein, we report a patient who developed anti-neutrophil cytoplasmic antibody associated crescentic IgA nephropathy within 3 months after autologous hematopoietic stem cell transplantation. He was treated with intravenous pulse steroids and monthly intravenous cyclophosphamide for 6 months followed by cyclophosphamide every 3 months and tapering dose of steroids. His proteinuria resolved and renal function remained stable. Two cases of crescentic IgA nephropathy have been reported in patients who underwent allogenic hematopoietic stem cell transplantation. The etiology of IgA nephropathy developing after hematopoietic stem cell transplantation is unclear and larger registry-based studies are needed to further explore this condition.


Asunto(s)
Anticuerpos Anticitoplasma de Neutrófilos/fisiología , Glomerulonefritis por IGA/diagnóstico , Glomerulonefritis por IGA/etiología , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Enfermedad de Hodgkin/terapia , Glomerulonefritis por IGA/terapia , Humanos , Masculino , Persona de Mediana Edad
18.
Neuroscience ; 155(3): 809-17, 2008 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-18582538

RESUMEN

Naked mole-rats are highly social rodents that live in large colonies characterized by a rigid social and reproductive hierarchy. Only one female, the queen, breeds. Most colony members are non-reproductive subordinates that work cooperatively to rear the young and maintain an underground burrow system. Little is known about the neurobiological basis of the complex sociality exhibited by this species. The neuropeptide oxytocin (Oxt) modulates social bonding and other social behaviors in many vertebrates. Here we examined the distribution of Oxt immunoreactivity in the brains of male and female naked mole-rats. As in other species, the majority of Oxt-immunoreactive (Oxt-ir) cells were found in the paraventricular and supraoptic nuclei, with additional labeled cells scattered throughout the preoptic and anterior hypothalamic areas. Oxt-ir fibers were found traveling toward and through the median eminence, as well as in the tenia tecta, septum, and nucleus of the diagonal band of Broca. A moderate network of fibers covered the bed nucleus of the stria terminalis and preoptic area, and a particularly dense fiber innervation of the nucleus accumbens and substantia innominata was observed. In the brainstem, Oxt-ir fibers were found in the periaqueductal gray, locus coeruleus, parabrachial nucleus, nucleus of the solitary tract, and nucleus ambiguus. The high levels of Oxt immunoreactivity in the nucleus accumbens and preoptic area are intriguing, given the link in other rodents between Oxt signaling in these regions and maternal behavior. Although only the queen gives birth or nurses pups in a naked mole-rat colony, most individuals actively participate in pup care.


Asunto(s)
Encéfalo/metabolismo , Oxitocina/metabolismo , Animales , Encéfalo/anatomía & histología , Mapeo Encefálico , Ratas Topo/anatomía & histología , Ratas Topo/metabolismo
19.
J Med Genet ; 44(2): e56, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17407838

RESUMEN

BACKGROUND: Despite advances in the characterisation of mutations in the MECP2-coding region, a small proportion of classic RTT cases remain without recognisable mutations. OBJECTIVE AND METHODS: To identify previously unknown mutations, a quantitative assay was established, providing estimates of MECP2_e1 and MECP2_e2 expression levels in peripheral blood. A systematic analysis of an Israeli cohort of 82 patients with classic and atypical RTT is presented, including sequence analysis of the MECP2-coding region, MLPA, XCI and quantitative expression assays. RESULTS AND CONCLUSION: A novel mis-sense mutation at ca 453C-->T (pD151E), resulting in a change of a conserved residue at the methyl-binding domain, and a rare GT deletion of intron 1 donor splice site are reported. It is shown that various MECP2 mutations had distinct effects on MECP2 expression levels in peripheral blood. The most significant (p<0.001) reduction in the expression of both MECP2 isoforms was related to the presence of the intron 1 donor splice-site mutation. Using quantitative expression assays, it was shown that several patients with classic and atypical RTT with no mutation findings had significantly lower MECP2 expression levels. Further research on these patients may disclose still elusive non-coding regulatory MECP2 mutations.


Asunto(s)
Proteína 2 de Unión a Metil-CpG/genética , Síndrome de Rett/genética , Cromosomas Humanos X , Estudios de Cohortes , Secuencia Conservada , ADN/genética , ADN/aislamiento & purificación , Femenino , Regulación de la Expresión Génica , Humanos , Israel , Masculino , Mutación Missense , Polimorfismo de Nucleótido Simple , Isoformas de Proteínas/genética , ARN/genética , ARN/aislamiento & purificación
20.
Mol Cell Biol ; 7(4): 1311-9, 1987 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-3037311

RESUMEN

Mutations in six genes that eliminate responsiveness of Saccharomyces cerevisiae a cells to alpha-factor were examined by assaying the binding of radioactively labeled alpha-factor to determine whether their lack of responsiveness was due to the absence of alpha-factor receptors. The ste2 mutants, known to be defective in the structural gene for the receptor, were found to lack receptors when grown at the restrictive temperature; these mutations probably affect the assembly of active receptors. Mutations in STE12 known to block STE2 mRNA accumulation also resulted in an absence of receptors. Mutations in STE4, 5, 7, and 11 partially reduced the number of binding sites, but this reduction was not sufficient to explain the loss of responsiveness; the products of these genes appear to affect postreceptor steps of the response pathway. As a second method of distinguishing the roles of the various STE genes, we examined the sterile mutants for suppression. Mating of the ste2-3 mutant was apparently limited by its sensitivity to alpha-factor, as its sterility was suppressed by mutation sst2-1, which leads to enhanced alpha-factor sensitivity. Sterility resulting from each of four ste4 mutations was suppressed partially by mutation sst2-1 or by mutation bar1-1 when one of three other mutations (ros1-1, ros2-1, or ros3-1) was also present. Sterility of the ste5-3 mutant was suppressed by mutation ros1-1 but not by sst2-1. The ste7, 11, and 12 mutations were not suppressed by ros1 or sst2. Our working model is that STE genes control the response to alpha-factor at two distinct steps. Defects at one step (requiring the STE2 gene are suppressed (directly or indirectly) by mutation sst2-1, whereas defects at the other step (requiring the STE5 gene) are suppressed by the ros1-1 mutation. The ste4 mutants are defective for both steps. Mutation ros1-1 was found to be allelic to cdc39-1. Map positions for genes STE2, STE12, ROS3, and FUR1 were determined.


Asunto(s)
Genes Fúngicos , Genes , Mutación , Péptidos/fisiología , Feromonas/fisiología , Receptores de Superficie Celular/genética , Receptores de Péptidos , Saccharomyces cerevisiae/genética , Factores de Transcripción , Alelos , Cruzamientos Genéticos , Genotipo , Factor de Apareamiento , Receptores de Superficie Celular/fisiología , Receptores del Factor de Conjugación , Saccharomyces cerevisiae/fisiología , Supresión Genética
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