Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 132
Filtrar
Más filtros

Tipo del documento
Intervalo de año de publicación
1.
Curr Psychiatry Rep ; 24(12): 889-896, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36422834

RESUMEN

PURPOSE OF REVIEW: As maternal mortality climbs in the USA with mental health conditions driving these preventable deaths, the field of reproductive psychiatry must shift towards identification of women and other birthing individuals at risk and facilitating access. This review brings together recent studies regarding risk of perinatal depression and highlights important comorbidities that place individuals at higher vulnerability to poor perinatal outcomes. RECENT FINDINGS: Recent research suggests that identifying risk for perinatal depression including historical diagnoses of depression, anxiety, trauma, and comorbid substance use and intimate partner violence may move the field to focus on preventive care in peripartum populations. Emerging data shows stark health inequities in racial and ethnic minority populations historically marginalized by the health system and in other vulnerable groups such as LGBTQ+ individuals and those with severe mental illness. Innovative models of care using systems-level approaches can provide opportunities for identification and risk analyses of vulnerable peripartum patients and facilitate access to therapeutic or preventive interventions. Utilizing intergenerational approaches and leveraging multidisciplinary teams that thoughtfully target high-risk women and other birthing individuals could promote significant changes to population-level care in maternal health.


Asunto(s)
Depresión Posparto , Embarazo , Femenino , Humanos , Depresión Posparto/diagnóstico , Depresión Posparto/terapia , Etnicidad , Grupos Minoritarios , Trastornos de Ansiedad , Ansiedad , Depresión/terapia , Periodo Posparto
2.
J Physiol ; 593(11): 2447-58, 2015 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-25809342

RESUMEN

KEY POINTS: Patients with transposition of the great arteries (TGA) and systemic right ventricles have premature congestive heart failure; there is also a growing concern that athletes who perform extraordinary endurance exercise may injure the right ventricle. Therefore we felt it essential to determine whether exercise training might injure a systemic right ventricle which is loaded with every heartbeat. Previous studies have shown that short term exercise training is feasible in TGA patients, but its effect on ventricular function is unclear. We demonstrate that systemic right ventricular function is preserved (and may be improved) in TGA patients with exercise training programmes that are typical of recreational and sports participation, with no evidence of injury on biomarker assessment. Stroke volume reserve during exercise correlates with exercise training response in our TGA patients, identifying this as a marker of a systemic right ventricle (SRV) that may most tolerate (and possibly even be improved by) exercise training. ABSTRACT: We aimed to assess the haemodynamic effects of exercise training in transposition of the great arteries (TGA) patients with systemic right ventricles (SRVs). TGA patients have limited exercise tolerance and early mortality due to systemic (right) ventricular failure. Whether exercise training enhances or injures the SRV is unclear. Fourteen asymptomatic patients (34 ± 10 years) with TGA and SRV were enrolled in a 12 week exercise training programme (moderate and high-intensity workouts). Controls were matched on age, gender, BMI and physical activity. Exercise testing pre- and post- training included: (a) submaximal and peak; (b) prolonged (60 min) submaximal endurance and (c) high-intensity intervals. Oxygen uptake (V̇O2; Douglas bag technique), cardiac output (Q̇c, foreign-gas rebreathing), ventricular function (echocardiography and cardiac MRI) and serum biomarkers were assessed. TGA patients had lower peak V̇O2, Q̇c, and stroke volume (SV), a blunted Q̇c/V̇O2 slope, and diminished SV response to exercise (SV increase from rest: TGA = 15.2%, controls = 68.9%, P < 0.001) compared with controls. After training, TGA patients increased peak V̇O2 by 6 ± 8.5%, similar to controls (interaction P = 0.24). The magnitude of SV reserve on initial testing correlated with Q̇c training response (r = 0.58, P = 0.047), though overall, no change in peak Q̇c was observed. High-sensitivity troponin T (hs-TnT) and N-terminal prohormone of brain naturetic peptide (NT pro-BNP) were low and did not change with acute exercise or after training. Our data show that TGA patients with SRVs in this study safely participated in exercise training and improved peak V̇O2. Neither prolonged submaximal exercise, nor high-intensity intervals, nor short-term exercise training seem to injure the systemic right ventricle.


Asunto(s)
Ejercicio Físico/fisiología , Ventrículos Cardíacos/fisiopatología , Transposición de los Grandes Vasos/fisiopatología , Función Ventricular Derecha/fisiología , Adulto , Gasto Cardíaco , Ecocardiografía , Prueba de Esfuerzo , Femenino , Humanos , Masculino , Volumen Sistólico
3.
Br J Sports Med ; 47 Suppl 1: i59-69, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24282209

RESUMEN

OBJECTIVES: To examine with a parallel group study design the performance and physiological responses to a 14-day off-season 'live high-train low in the heat' training camp in elite football players. METHODS: Seventeen professional Australian Rules Football players participated in outdoor football-specific skills (32 ± 1°C, 11.5 h) and indoor strength (23 ± 1°C, 9.3 h) sessions and slept (12 nights) and cycled indoors (4.3 h) in either normal air (NORM, n=8) or normobaric hypoxia (14 ± 1 h/day, FiO2 15.2-14.3%, corresponding to a simulated altitude of 2500-3000 m, hypoxic (HYP), n=9). They completed the Yo-Yo Intermittent Recovery level 2 (Yo-YoIR2) in temperate conditions (23 ± 1°C, normal air) precamp (Pre) and postcamp (Post). Plasma volume (PV) and haemoglobin mass (Hb(mass)) were measured at similar times and 4 weeks postcamp (4WPost). Sweat sodium concentration ((Na(+))(sweat)) was measured Pre and Post during a heat-response test (44°C). RESULTS: Both groups showed very large improvements in Yo-YoIR2 at Post (+44%; 90% CL 38, 50), with no between-group differences in the changes (-1%; -9, 9). Postcamp, large changes in PV (+5.6%; -1.8, 5.6) and (Na(+))sweat (-29%; -37, -19) were observed in both groups, while Hb(mass) only moderately increased in HYP (+2.6%; 0.5, 4.5). At 4WPost, there was a likely slightly greater increase in Hb(mass) (+4.6%; 0.0, 9.3) and PV (+6%; -5, 18, unclear) in HYP than in NORM. CONCLUSIONS: The combination of heat and hypoxic exposure during sleep/training might offer a promising 'conditioning cocktail' in team sports.


Asunto(s)
Altitud , Fútbol Americano/fisiología , Aclimatación/fisiología , Rendimiento Atlético/fisiología , Presión Atmosférica , Australia , Volumen Sanguíneo/fisiología , Ejercicio Físico/fisiología , Hemoglobinas/metabolismo , Calor , Humanos , Hipoxia/fisiopatología , Carrera/fisiología , Sueño/fisiología
4.
Plant Dis ; 96(3): 384-388, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30727135

RESUMEN

The identity of 172 isolates of Pythium spp. from cavity spot lesions on carrot produced in California and Michigan was determined, and their sensitivity to three fungicides was examined. Pythium violae accounted for 85% of California isolates, with P. irregulare, P. dissotocum (the first report as a carrot pathogen in the United States), P. ultimum, and P. sulcatum making the balance. P. sulcatum, P. sylvaticum, and P. intermedium were the most commonly recovered (85%) species in Michigan; others from Michigan included P. intermedium, P. irregulare, and an unclassified strain, M2-05. On fungicide-amended media, 93% of isolates were sensitive to mefenoxam (inhibition of mycelial growth was >60% at 10 µg active ingredient [a.i.]/ml); however, two of five isolates of P. irregulare from California were highly resistant (≤60% inhibition at 100 µg a.i./ml); about half of the isolates of P. intermedium and P. sylvaticum and a single isolate of P. violae were highly or intermediately resistant to mefenoxam (>60% inhibition at 100 µg a.i./ml, or ≤60% inhibition at 10 µg a.i./ml). P. dissotocum, P. irregulare, P. sulcatum, M2-05, and three of seven isolates of P. intermedium were insensitive to fluopicolide (effective concentrations for 50% growth inhibition [EC50] were >50 µg a.i./ml), while P. sylvaticum, P. ultimum, P. violae, and some isolates in P. intermedium were sensitive (EC50 < 1 µg a.i./ml). All isolates were sensitive to zoxamide (EC50 < 1 µg a.i./ml). Sensitivity baselines of P. violae to zoxamide and fluopicolide were established.

6.
Appl Environ Microbiol ; 74(12): 3652-7, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18456854

RESUMEN

Xylella fastidiosa is a gram-negative plant pathogenic bacterium that causes almond leaf scorch disease (ALSD) and Pierce's disease (PD) of grape in many regions of North America and Mexico. Of the two 16S rRNA gene genotypes described in California, A genotype strains cause ALSD only and G genotype strains cause both PD and ALSD. While G genotype strains cause two different diseases, little is known about their genetic variation. In this study, we identified a putative protease locus, PD0218 (pspB), in the genome of X. fastidiosa and evaluated the variation at this locus in X. fastidiosa populations. PD0218 contains tandem repeats of ACDCCA, translated to threonine and proline (TP), upstream of the putative protease conserved domain. Among 116 X. fastidiosa ALSD and PD strains isolated from seven locations in California, tandem repeat numbers (TRNs) varied from 9 to 47, with a total of 30 TRN genotypes, indicating that X. fastidiosa possesses an active mechanism for contracting and expanding tandem repeats at this locus. Significant TRN variation was found among PD strains (mean = 29.9), which could be further divided into two TRN groups: PD-G(small) (mean = 17.3) and PD-G(large) (mean = 44.3). Less variation was found in ALSD strains (mean = 21.7). The variation was even smaller after ALSD strains were subdivided into the A and G genotypes (mean = 13.3, for the G genotype; mean = 27.1, for the A genotype). Genetic variation at the PD0218 locus is potentially useful for sensitive discrimination of X. fastidiosa strains. However, TRN stability, variation range, and correlation to phenotypes should be evaluated in epidemiological applications such as pathotype identification and delineation of pathogen origin.


Asunto(s)
Péptido Hidrolasas/genética , Polimorfismo Genético , Xylella/enzimología , Xylella/genética , Secuencia de Aminoácidos , California , ADN Bacteriano/genética , Genotipo , Datos de Secuencia Molecular , Enfermedades de las Plantas/microbiología , Reacción en Cadena de la Polimerasa , Prunus/microbiología , Alineación de Secuencia , Análisis de Secuencia de ADN , Secuencias Repetidas en Tándem , Vitis/microbiología , Xylella/clasificación , Xylella/aislamiento & purificación
7.
West Indian Med J ; 56(3): 213-22, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18072399

RESUMEN

Given that the health of many immigrants declines after increasing years in their host countries and that there may be gender differences in these experiences, this exploratory study's main objective was twofold: a) assess the relationship between acculturative stress and negative health (ie both mental and physical) and b) determine if there were any gender differences in these stress-health relationships. Gender-stratified analyses were conducted on a sample of 418 (males = 158, females = 260) English-speaking immigrants (the majority of whom were Jamaicans--males = 81%, females = 86%) that lived in the District of Columbia, Virginia, and Maryland (DC Metropolitan Area, United States of America (USA). Mail-order surveys were used to collect the data over a six-month period in 2002. Data for the main independent variable, acculturative stress, were collected using five indices (ie personal problems, group affiliations, adjustment to life in the USA, lonely feelings and feeling socially satisfied). Data for the major dependent variable, health, were collected using four indices (ie symptoms of depression, physical health conditions, the rating of one's health and the feeling of control one had over one's health). After controlling for selected covariates, both males (r = 0.42, p < 0.001) and females (r = 0.19, p < 0.05) reported a positive relationship between personal problems and depression. In other cases, female immigrants, with increasing personal problems, reported more physical health problems (r = 0.20, p < 0.05). Male immigrants who had more group affiliations (r = 0.22, p < 0.05), and who reported more loneliness (r = .26, p < 0.05) had less symptoms of depression. These exploratory results suggest the potential importance of selected variables (eg personal problems and depression) in efforts at improving the health of Caribbean immigrants.


Asunto(s)
Aculturación , Adaptación Psicológica , Emigración e Inmigración , Identidad de Género , Estado de Salud , Estrés Psicológico , Adulto , Región del Caribe , Estudios Transversales , Escolaridad , Femenino , Encuestas Epidemiológicas , Humanos , Jamaica , Masculino , Pruebas Psicológicas , Psicometría , Clase Social , Aislamiento Social , Encuestas y Cuestionarios , Estados Unidos
8.
Knee ; 24(6): 1442-1447, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28970126

RESUMEN

BACKGROUND: The aim of this study was to compare the medium term functional outcome and patient satisfaction of gap balanced (GB) with measured resection (MR) total knee arthroplasty (TKA) using computer navigation. METHODS: A cohort of 144 consecutive computer navigated TKA were retrospectively identified from an arthroplasty database. Functional assessment using the Oxford Knee Score (OKS) and patient satisfaction were obtained from 113 patients at a mean follow-up of 5.4 (range four to seven) years. There were 44 patients in the GB group and 69 patients in the MR group. RESULTS: The mean OKS for the GB group was 36.9 (SD 9.2) and for the MR was 33.6 (SD 9.8), with a difference of 3.3 (95% CI 0.3 to 6.3) points, which was statistically significant (p=0.01). Linear regression analysis confirmed the independent effect of surgical technique when adjusting for confounding factors and surgeon, with the GB group achieving a greater post-operative OKS (R2=0.39, 3.0 points, 95% CI 1.2 to 4.8, p=0.001). There was a greater rate of patient satisfaction in the GB group (88.6%, n=39/44) compared to the MR group (81.1%, n=56/69), but this was not statistically significant (odds ratio 1.8, 95% CI 0.6 to 5.5, p=0.31). CONCLUSION: Computer navigated Columbus® TKA using a GB technique results in a statistically significantly greater functional outcome but no significant difference in patient satisfaction in the medium term compared to patients undergoing a MR technique.


Asunto(s)
Artroplastia de Reemplazo de Rodilla/métodos , Cirugía Asistida por Computador/métodos , Anciano , Fenómenos Biomecánicos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Satisfacción del Paciente/estadística & datos numéricos , Estudios Retrospectivos , Resultado del Tratamiento
9.
Plant Dis ; 90(6): 826, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30781249

RESUMEN

Maize (Zea mays L.) is an important annual forage crop cultivated in the Sultanate of Oman, especially during the summer months. It is used for green fodder and grains and often intercropped in fruit orchards, especially under date palms. In April of 2005, leaf samples showing rust symptoms were collected from Samail, 100 km south of Muscat. Oval-shaped, red-brown pustules covered both sides of the leaves and yielded urediniospores typical of Puccinia sorghi Schwein. Urediniospores were roughly subglobose, measured 23 to 28 × 20 to 25 µm, echinulate, with three or four equitorial germ pores (2). Teliospores (38 to 42 × 16 to 19 µm) were observed, but few in numbers, most probably because of the time of year of collection. Pathogen identity was confirmed by nuclear ribosomal large subunit (28S) and internal transcribed spacer region 2 (ITS-2) DNA analysis (voucher sequence deposited in GenBank, Accession No. DQ345724, voucher specimen deposited in the U.S. National Fungus Collections, BPI 871134). P. sorghi has previously been reported from Yemen and Saudi Arabia (1) but not from Oman. Maize is grown throughout the year in Oman, and pathogen survival probably does not require the presence of the alternate host, nonetheless, Oxalis species are present and current research is attempting to locate and confirm the presence of the aecial stage in Oman. References: (1) CMI Distribution Maps of Plant Diseases. Map No. 279. Ed. 4. CABI, Wallingford, UK, 1978. (2) D. G. White, ed. Compendium of Corn Diseases. The American Phytopathological Society, St Paul, MN, 1999.

10.
Plant Dis ; 90(2): 248, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30786432

RESUMEN

Polygala mascatense Boiss. (family Polygalaceae) is a common weed found in neglected farms, under date palm trees, and in stony locations throughout the Sultanate of Oman (1). It is a perennial herb approximately 30 to 40 cm tall, has slender branches, is woody at the base, and has linear leaves with purple flowers. Recently (November 2004), in the interior region of Oman (210 km south of Muscat), some polygala plants were found stunted with small leaves, bushy growth, and the floral parts were showing phyllody symptoms. Total genomic DNA extracted from asymptomatic and symptomatic plants with modified cetyltrimethylammoniumbromide (CTAB) buffer method (4) was used as a template for direct polymerase chain reaction (PCR) amplification of phytoplasma 16S rDNA with P1/P7 primers. Direct PCR product was used as template DNA for nested PCR with primers R16F2n/R16R2. DNA from plants infected with alfalfa and lime witches'-broom phytoplasma was used as positive controls, and DNA from healthy plants and water was used as negative controls. Products from nested PCR (1.2 kb) were analyzed by using single endonuclease enzyme digestion (restriction fragment length polymorphism [RFLP]) with Tru9I, HaeIII, HhaI, TaqI, AluI, and RsaI (3). The results showed the presence of a 1.8-kb product amplified with direct PCR and a 1.2-kb product of the nested PCR from infected polygala and the positive controls, whereas no PCR products were observed in the negative controls. The PCR assay confirmed the presence of phytoplasma causing witches'-broom disease in polygala. The RFLP results showed the polygala phyto-plasma to be most similar to the alfalfa phytoplasma, a member of 16SrII group (2). Infected polygala weeds may serve as a reservoir for alfalfa witches'-broom phytoplasma that causes annual losses over $25 million to alfalfa cultivation in Oman (2). A detailed investigation needs to be carried out to establish transmission of phytoplasma from polygala to alfalfa. To our knowledge, this is the first report of phytoplasma infecting polygala weeds in Oman. References: (1) S. A. Ghazanfar. Pages 95-96 in: An Annotated Catalogue of the Vascular Plants in Oman. Scripta Botanica Belgica Meise, National Botanic Garden of Belgium, 1992. (2) A. J. Khan et al. Phytopathology 92:1038, 2002. (3) I. M. Lee et al. Int. J. Syst. Bacteriol. 1153, 1998. (4) M. A. Saghai-Maroof et al. Proc. Natl. Acad. Sci. USA 81:8014, 1984.

11.
Clin Cancer Res ; 7(6): 1618-26, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11410498

RESUMEN

PURPOSE: Transforming growth factor beta (TGF-beta) regulates cell growth and differentiation, in normal squamous epithelium, via specific TGF-beta receptors and intracellular signaling molecules (Smads). We have previously observed that TGF-beta type II receptor (TbetaR-II) expression decreases in squamous cell carcinomas as tumors become less differentiated and more biologically aggressive. However, a small fraction of tumors remain TbetaR-II positive. In this article, we examine the integrity of the other members of the TGF-beta-signaling machinery, the Smad proteins. EXPERIMENTAL DESIGN: Thirteen archived head and neck squamous cell carcinomas were selected from the files of the Pathology Department of the H. Lee Moffitt Cancer Center. Protein immunoexpression was quantitated by image analysis in the context of histopathological parameters. Mutation analysis of the MADR2/Smad2 gene was also performed. RESULTS: In both TbetaR-II-positive and TbetaR-II-negative tumors, expression of the non-TGF-beta-specific Smads (4, 6, and 7) was variable, whereas expression of the pathway-specific Smad2 was lost in 38% of the tumors. Expression of the activated, phosphorylated form of this molecule, Smad2-P, was lost in approximately 70% of the tumors. No abnormal mRNA expression and no mutations in the MADR2/Smad2 gene were observed. CONCLUSIONS: These results suggest that multiple defects in TGF-beta signaling, both at the receptor and postreceptor level, may play a role in the oncogenesis of head and neck squamous cell carcinoma.


Asunto(s)
Carcinoma de Células Escamosas/metabolismo , Proteínas de Unión al ADN/metabolismo , Neoplasias de Cabeza y Cuello/metabolismo , Transducción de Señal , Transactivadores/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Anciano , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patología , Diferenciación Celular , División Celular , Núcleo Celular/metabolismo , Análisis Mutacional de ADN , Proteínas de Unión al ADN/genética , Activación Enzimática , Epitelio/metabolismo , Femenino , Neoplasias de Cabeza y Cuello/genética , Neoplasias de Cabeza y Cuello/patología , Humanos , Procesamiento de Imagen Asistido por Computador , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Mutación , Fosforilación , Reacción en Cadena de la Polimerasa , ARN Mensajero/metabolismo , Receptores de Factores de Crecimiento Transformadores beta/genética , Receptores de Factores de Crecimiento Transformadores beta/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Proteína Smad2 , Proteína smad6 , Proteína smad7 , Transactivadores/genética
12.
J Environ Qual ; 34(5): 1682-6, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16091621

RESUMEN

Applications of animal manures have increased soil test P values in many parts of the USA and thus increased the risk that soil P will be transferred to surface water and decrease water quality. To continue farming these areas, landowners need tools to reduce the risk of P losses. A field experiment was conducted near Kurten, TX, on a Zulch fine sandy loam (thermic Udertic Paleustalfs) with Bray-1 P values exceeding 3000 mg P kg(-1) soil (dry wt.) in the A(p) horizon to evaluate the effectiveness of soil amendments for reducing soil test P values. Soils were amended annually from 1999 to 2001 with 1.5 and 5.0 Mg gypsum ha(-1), 1.4 Mg alum ha(-1), or 24.4 Mg ha(-1) of waste paper product high in Al alone or in combination with 1.5 Mg gypsum ha(-1) and/or 1.4 Mg alum ha(-1). These treatments supplied a maximum of 225 and 1163 kg ha(-1) yr(-1) of Al and Ca, respectively. Soil Bray-1 P and dissolved reactive P levels were monitored from 1999 to 2004. None of the soil amendment treatments affected Bray-1 P values. Only annual additions of 5.0 Mg gypsum ha(-1) from 1999 to 2001 significantly reduced soil dissolved reactive P. Dissolved reactive P levels reached minimal levels after two applications of 5.0 Mg gypsum ha(-1) but increased in 2003 and 2004. These results indicate that soil dissolved reactive P levels can be reduced if sufficient amounts of gypsum were added to supply Ca in amounts similar to the soil test P values.


Asunto(s)
Contaminantes Ambientales/análisis , Estiércol , Fósforo/análisis , Suelo/análisis , Agricultura/métodos , Compuestos de Alumbre/química , Sulfato de Calcio/química , Fósforo/química , Texas
13.
Gene ; 101(1): 33-44, 1991 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-1676385

RESUMEN

Type-4 fimbriae (pili) are associated with a phenomenon known as twitching motility, which appears to be involved with bacterial translocation across solid surfaces. Pseudomonas aeruginosa mutants which produce fimbriae, but which have lost the twitching motility function, display altered colony morphology and resistance to fimbrial-specific bacteriophage. We have used phenotypic complementation of such mutants to isolate a region of DNA involved in twitching motility. This region was physically mapped to a SpeI fragment around 20 min on the P. aeruginosa PAO chromosome, remote from the major fimbrial locus (around 75 min) where the structural subunit-encoding gene (fimA/pilA) and ancillary genes required for fimbrial assembly (pilB, C and D) are found. A gene, pilT, within the twitching motility region is predicted to encode a 344-amino acid protein which has strong homology to a variety of other bacterial proteins. These include the P. aeruginosa PilB protein, the ComG ORF-1 protein from the Bacillus subtilis comG operon (necessary for competence), the PulE protein from the Klebsiella oxytoca (formerly K. pneumoniae) pulC-O operon (involved in pullulanase export), and the VirB-11 protein from the virB operon (involved in virulence) which is located on the Agrobacterium tumefaciens Ti plasmid. We have also identified other sets of homologies between P. aeruginosa fimbrial assembly (Pil) proteins and B. subtilis Com and K. oxytoca Pul proteins, which suggest that these are all related members of a specialised protein export pathway which is widespread in the eubacteria.


Asunto(s)
Fimbrias Bacterianas , Genes Bacterianos , Pseudomonas aeruginosa/genética , Secuencia de Aminoácidos , Secuencia de Bases , Transporte Biológico Activo/genética , Datos de Secuencia Molecular , Sistemas de Lectura Abierta/genética , Mapeo Restrictivo , Homología de Secuencia de Ácido Nucleico
14.
Cancer Lett ; 171(2): 209-14, 2001 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-11520605

RESUMEN

Retinoblastoma gene (Rb) defects occur frequently in human tumors. Studies of Rb-defective human tumor cell lines and Rb-/- murine embryonic fibroblasts demonstrate that Rb is required for interferon-gamma (IFN-gamma) induced major histocompatibility complex (MHC) class II expression. MHC class II expressing tumors generate anti-tumor immune responses associated with tumor-specific infiltrating lymphocytes. The role of Rb in IFN-gamma induced MHC class II expression on an endogenous tumor was examined by immunohistochemical staining for IAbeta and Rb on tissues from Rb+/- mice. MHC class II IAbeta is not induced by IFN-gamma in Rb-deficient neoplastic cells, but remains inducible in related normal tissue.


Asunto(s)
Genes de Retinoblastoma/genética , Antígenos de Histocompatibilidad Clase II/biosíntesis , Lesiones Precancerosas/genética , Proteína de Retinoblastoma/deficiencia , Animales , Femenino , Regulación de la Expresión Génica , Genes MHC Clase II , Antígenos de Histocompatibilidad Clase II/genética , Hiperplasia/inmunología , Hiperplasia/metabolismo , Inmunohistoquímica , Interferón gamma/farmacología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Lesiones Precancerosas/inmunología , Lesiones Precancerosas/metabolismo , Proteína de Retinoblastoma/fisiología
15.
Hum Pathol ; 31(1): 58-62, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10665914

RESUMEN

The distinction between metastatic small cell lung carcinoma (SCLC) and Merkel cell tumor is difficult by routine histology, prompting the search for specific markers that could separate these neoplasms. Thyroid transcription factor 1 (TFF-1) is a homeodomain containing transcription factor expressed in the normal airway epithelium. The expression of TTF-1 has also been shown in adenocarcinomas and small cell carcinomas of the lung. However, the utility of TTF-1 to differentiate between SCLC and Merkel cell tumor has not yet been investigated. In this study, paraffin sections of 36 SCLCs and 21 Merkel cell tumors were analyzed for the presence of immunoreactive TTF-1 and cytokeratin 20 (CK20), a marker previously demonstrated in Merkel cell tumors. Monoclonal TTF-1 and CK20 antibodies were used with a biotin-streptavidin detection system. Immunostaining for TTF-1 was observed in 97% of SCLCs and in no Merkel cell tumors. Immunoreactivity for CK20 was demonstrated in 76% of Merkel cell tumors and 3% of SCLCs. These data indicate that TTF-1 is a sensitive (97%) and specific (100%) marker for SCLCs and can be used to differentiate SCLCs from Merkel cell tumors.


Asunto(s)
Carcinoma de Células de Merkel/metabolismo , Carcinoma de Células Pequeñas/metabolismo , Neoplasias Pulmonares/metabolismo , Proteínas Nucleares/metabolismo , Neoplasias Cutáneas/metabolismo , Factores de Transcripción/metabolismo , Carcinoma de Células de Merkel/patología , Carcinoma de Células Pequeñas/patología , Humanos , Inmunohistoquímica , Proteínas de Filamentos Intermediarios/metabolismo , Queratina-20 , Neoplasias Pulmonares/patología , Neoplasias Cutáneas/patología , Factor Nuclear Tiroideo 1
16.
Psychopharmacology (Berl) ; 94(4): 540-4, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-3131801

RESUMEN

The effects of 60 min pretreatment with the enkephalinase inhibitor acetorphan were assessed on naloxone-precipitated (2.5 mg/kg IP) abstinence in chronically morphinized rats. In addition, the antinociceptive activity of the compound was investigated in mice. Intraperitoneal injection (50 mg/kg) in rats attenuated some aspects of the opioid withdrawal syndrome such as burrowing, wet dog shakes, squeal on touch hostility, tachypnoea, ptosis and rough hair, whereas jumping and escape behaviour were significantly increased in acetorphan-treated animals. No effect was observed on withdrawal hypothermia or acute weight loss. Similarly, chronic dosing with acetorphan after withdrawal produced no significant effect on body weight. Acetorphan (50 mg/kg IP) failed to produce any antinociceptive activity in the mouse tail immersion test, but potentiated the antinociceptive effect of D-Ala2-D-Leu5-enkephalin. These results are discussed in terms of acetorphan crossing the blood-brain barrier before being hydrolysed to thiorphan, thus yielding opioid withdrawal relieving effects.


Asunto(s)
Aminoácidos Sulfúricos/uso terapéutico , Analgésicos/uso terapéutico , Morfina/efectos adversos , Naloxona/farmacología , Síndrome de Abstinencia a Sustancias/tratamiento farmacológico , Tiorfan/análogos & derivados , Tiopronina/uso terapéutico , Animales , Temperatura Corporal/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Masculino , Metaloendopeptidasas/antagonistas & inhibidores , Ratones , Ratones Endogámicos , Dependencia de Morfina , Neprilisina , Ratas , Ratas Endogámicas , Tiopronina/análogos & derivados
17.
Mutat Res ; 361(1): 1-9, 1996 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-8816936

RESUMEN

Cigarette smokers have been reported to void urine which is more mutagenic, as measured in the Ames assay, than urine voided by non-smokers. Condensate from the mainstream smoke of a cigarette which primarily heats tobacco (test cigarette) has shown significantly reduced mutagenicity in a battery of in vitro genotoxicity assays compared with tobacco-burning cigarettes. The objective of this study was to determine whether the reduction in mutagenic activity observed in the in vitro assays would be reflected in the urine of smokers of the test cigarette. Twenty smokers were enrolled in a 4-week crossover study, with each smoker consuming test cigarettes ad libitum for a week and their usual brand of tobacco-burning cigarettes the other 3 weeks. Diet was strictly controlled throughout the study, and broiled and pan-fried meat was not served to minimize ingestion of mutagenic protein pyrolysis products. There was no statistically significant difference (p = 0.06) in consumption of tobacco-heating and tobacco-burning cigarettes. There were no statistically significant differences (p = 0.22) in salivary cotinine concentrations for smokers when smoking either tobacco-burning or tobacco-heating cigarettes. Urinary nicotine (ng/mg creatinine) was not different (p = 0.31) for smokers when smoking either tobacco-burning or tobacco-heating cigarettes. Urinary cotinine (ng/mg creatinine) was 32% lower (p = 0.0004) when smoking tobacco-heating cigarettes as compared with smoking tobacco-burning cigarettes. Twenty-four-hour urine samples were collected twice weekly, concentrated using XAD-2 resin and tested in Ames strains TA98 and YG1024 with metabolic activation. Tobacco-burning cigarette smokers experienced a 79% reduction in urinary mutagenicity as measured in strain YG1024 and a 72% reduction as measured in strain TA98 during the week that they smoked the tobacco-heating cigarette while maintaining a fixed dietary regimen. The results of this study indicate that smokers of tobacco-heating cigarettes void urine which is significantly less mutagenic than urine voided by smokers of tobacco-burning cigarettes.


Asunto(s)
Mutágenos/metabolismo , Fumar/orina , Cotinina/orina , Estudios Cruzados , Dieta , Femenino , Calor , Humanos , Masculino , Pruebas de Mutagenicidad , Nicotina/orina , Plantas Tóxicas , Saliva/metabolismo , Nicotiana
18.
Arch Otolaryngol Head Neck Surg ; 125(1): 76-81, 1999 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9932593

RESUMEN

OBJECTIVE: To investigate the role of cell cycle regulators in the pathogenesis of papillary carcinoma of the thyroid. DESIGN: Resistance to transforming growth factor beta-mediated inhibition is a well-known pathogenic mechanism in epithelial neoplasias. In a retrospective study, the expression of transforming growth factor beta receptors types I and II, cyclin D1, and the cyclin-dependent inhibitor p27kip, was analyzed by immunohistochemistry. Results were interpreted in the context of clinicopathological data. Patient follow-up ranged from 1 to 18 years, with a mean of 4 years. MATERIALS: Twenty conventional primary papillary carcinomas and their metastases were selected according to current pathologic criteria. Nonconventional papillary carcinomas (eg, tall-cell, columnar) were excluded from the analysis. RESULTS: Cyclin D1 was expressed more intensely in the tumor than in adjacent nonneoplastic parenchyma. Within a given tumor, however, there was significant heterogeneity in expression intensity and percentage of positive cells, particularly in metastases. Type I receptors were strongly expressed in 90% of tumors, while 80% of the tumors revealed low to no expression of type II receptors. In 10% of tumors, type I receptors were absent and type II receptors expressed. Simultaneous absence of both receptors was not observed. While p27kip was strongly expressed in nonneoplastic thyroid, it was not detected in any of the primary tumors or their metastases. CONCLUSIONS: The results strongly suggest that functional abnormalities in type II receptors result in increased levels of cyclin D1 and down-regulation of p27kip. This would maintain cells in a proliferative state and would promote tumor progression.


Asunto(s)
Biomarcadores de Tumor/análisis , Carcinoma Papilar/patología , Proteínas de Ciclo Celular , Proteínas Asociadas a Microtúbulos/análisis , Receptores de Factores de Crecimiento Transformadores beta/análisis , Neoplasias de la Tiroides/patología , Proteínas Supresoras de Tumor , Adulto , Ciclo Celular/fisiología , Ciclina D1/análisis , Inhibidor p27 de las Quinasas Dependientes de la Ciclina , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Glándula Tiroides/patología
19.
Arch Otolaryngol Head Neck Surg ; 125(8): 849-54, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10448730

RESUMEN

OBJECTIVES: To study the intracellular location of transforming growth factor beta type II receptors (TbetaR-II) in verrucous carcinoma (VC) and squamous cell carcinoma (SqCC), and to evaluate their role in the biological behavior of both neoplasias. DESIGN: Ten VC and 10 well-differentiated SqCC specimens were analyzed by immunohistochemistry and in situ hybridization for the expression and intracellular location of TbetaR-II. Receptor expression was evaluated in areas of invasion and in areas of transformation of VC into SqCC. TbetaR-II expression was compared with expression of the type I receptor (TbetaR-I). SUBJECTS: Formalin-fixed, paraffin-embedded tissue sections from VCs and well-differentiated SqCCs, operated on at the H. L. Moffitt Cancer Center and Research Institute from May 1987 to January 1998, were selected for the study. INTERVENTIONS: None. RESULTS: While in all VCs TbetaR-II was found to be located along the membrane of the neoplastic keratinocytes, TbetaR-II expression in SqCC was observed predominantly in a cytoplasmic location. This cytoplasmic location of TbetaR-II was also seen in areas of transition from VC to SqCC. Expression of TbetaR-I was found in a cytoplasmic location in both tumor types. CONCLUSIONS: The membranous location of TbetaR-II in VC exposes the receptor to the growth inhibitory control of TGF-beta and may explain why VC tumors are less aggressive clinically. The marked reduction of membranous TbetaR-II and their predominant cytoplasmic location diminishes TGF-beta growth inhibition and may contribute to the transformation of VC into the more aggressive SqCC.


Asunto(s)
Receptores de Activinas Tipo I , Carcinoma de Células Escamosas/metabolismo , Carcinoma Verrugoso/metabolismo , Neoplasias de Cabeza y Cuello/metabolismo , Receptores de Factores de Crecimiento Transformadores beta/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Adulto , Anciano , Carcinoma de Células Escamosas/patología , Carcinoma Verrugoso/patología , Sondas de ADN/química , Femenino , Neoplasias de Cabeza y Cuello/patología , Humanos , Técnicas para Inmunoenzimas , Hibridación in Situ , Masculino , Persona de Mediana Edad , Proteínas Serina-Treonina Quinasas/metabolismo , ARN Mensajero/metabolismo , Receptor Tipo I de Factor de Crecimiento Transformador beta , Receptor Tipo II de Factor de Crecimiento Transformador beta , Receptores de Factores de Crecimiento Transformadores beta/genética , Factor de Crecimiento Transformador beta/genética
20.
Am Surg ; 54(6): 386-9, 1988 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3377333

RESUMEN

A retrospective analysis of the medical records of 17 consecutive patients undergoing lower extremity amputation and Immediate Postoperative Prosthesis (IPOP) placement for infectious complications of unreconstructable arterial insufficiency was performed. Significant soft tissue infection was present in 13 patients and osteomyelitis in four. The mean patient age was 59.4 years and 13 of 17 patients were diabetic. Fourteen patients underwent below knee and three underwent above knee amputations. Seven patients had undergone previous arterial reconstruction. Thirteen patients had previous ipsilateral amputations, five of which were open guillotine amputations performed between 3 and 7 days prior to definitive surgery. Four individuals (24%) required early removal of the IPOP, two due to patient noncompliance and two due to stump healing complications. Thirteen patients (76%) were successfully treated with IPOP and went on to achieve independent gait within 3 weeks of their definitive amputation.


Asunto(s)
Miembros Artificiales , Celulitis (Flemón)/cirugía , Osteomielitis/cirugía , Insuficiencia Venosa/cirugía , Adulto , Anciano , Humanos , Pierna , Masculino , Persona de Mediana Edad , Cuidados Posoperatorios , Estudios Retrospectivos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA