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1.
Semin Cancer Biol ; 77: 3-28, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-33607246

RESUMEN

Ovarian cancer typically presents at an advanced stage, and although the majority of cases initially respond well to platinum-based therapies, chemoresistance almost always occurs leading to a poor long-term prognosis. While various cellular autonomous mechanisms contribute to intrinsic or acquired platinum resistance, the tumour microenvironment (TME) plays a central role in resistance to therapy and disease progression by providing cancer stem cell niches, promoting tumour cell metabolic reprogramming, reducing chemotherapy drug perfusion and promoting an immunosuppressive environment. As such, the TME is an attractive therapeutic target which has been the focus of intense research in recent years. This review provides an overview of the unique ovarian cancer TME and its role in disease progression and therapy resistance, highlighting some of the latest preclinical and clinical data on TME-targeted therapies. In particular, it focuses on strategies targeting cancer-associated fibroblasts, tumour-associated macrophages, cancer stem cells and cancer cell metabolic vulnerabilities.


Asunto(s)
Carcinoma Epitelial de Ovario/patología , Resistencia a Antineoplásicos/fisiología , Microambiente Tumoral/fisiología , Animales , Carcinoma Epitelial de Ovario/inmunología , Femenino , Humanos
2.
Phys Rev Lett ; 129(19): 195002, 2022 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-36399755

RESUMEN

The application of an external 26 Tesla axial magnetic field to a D_{2} gas-filled capsule indirectly driven on the National Ignition Facility is observed to increase the ion temperature by 40% and the neutron yield by a factor of 3.2 in a hot spot with areal density and temperature approaching what is required for fusion ignition [1]. The improvements are determined from energy spectral measurements of the 2.45 MeV neutrons from the D(d,n)^{3}He reaction, and the compressed central core B field is estimated to be ∼4.9 kT using the 14.1 MeV secondary neutrons from the D(T,n)^{4}He reactions. The experiments use a 30 kV pulsed-power system to deliver a ∼3 µs current pulse to a solenoidal coil wrapped around a novel high-electrical-resistivity AuTa_{4} hohlraum. Radiation magnetohydrodynamic simulations are consistent with the experiment.

3.
Br J Cancer ; 113(2): 311-20, 2015 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-26079303

RESUMEN

BACKGROUND: Variations in systemic inflammatory response biomarker levels have been associated with adverse clinical outcome in various malignancies. This study determined the prognostic significance of preoperative neutrophil:lymphocyte (NLR), platelet:lymphocyte (PLR) and monocyte:lymphocyte (MLR) ratios in endometrial cancer. METHODS: Clinicopathological and 5-year follow-up data were obtained for a retrospective series of surgically treated endometrial cancer patients (n=605). Prognostic significance was determined for overall (OS) and cancer-specific survival (CSS) using Cox proportional hazards models and Kaplan-Meier analysis. Receiver-operator characteristic and log-rank functions were used to optimise cut-offs. NLR, PLR and MLR associations with clinicopathological variables were determined using non-parametric tests. RESULTS: Applying cut-offs of ⩾2.4 (NLR), ⩾240 (PLR) and ⩾0.19 (MLR), NLR and PLR (but not MLR) had independent prognostic significance. Combining NLR and PLR scores stratified patients into low (NLR-low and PLR-low), intermediate (NLR-high or PLR-high) and high risk (NLR-high and PLR-high) groups: multivariable hazard ratio (HR) 2.51; P<0.001 (OS); HR 2.26; P<0.01 (CSS) for high vs low risk patients. Increased NLR and PLR were most strongly associated with advanced stage (P<0.001), whereas increased MLR was strongly associated with older age (P<0.001). CONCLUSION: Both NLR and PLR are independent prognostic indicators for endometrial cancer, which can be combined to provide additional patient stratification.


Asunto(s)
Plaquetas , Neoplasias Endometriales/mortalidad , Linfocitos , Neutrófilos , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Neoplasias Endometriales/sangre , Neoplasias Endometriales/patología , Femenino , Humanos , Persona de Mediana Edad , Análisis Multivariante , Estadificación de Neoplasias , Pronóstico , Estudios Retrospectivos
4.
Reproduction ; 150(2): 127-38, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26015594

RESUMEN

The endometrium is a dynamic tissue, demonstrating cyclical growth/remodelling in preparation for implantation. In mice, seminal constituents trigger mechanisms to prepare the endometrium, a process dubbed 'seminal priming' that modifies immune system components and mediates endometrial remodelling in preparation for pregnancy. An array of cytokines has been reported to mediate this interaction, although much of the literature relates to in vitro studies on isolated endometrial epithelial cells. This study measured changes in immune-related gene expression in endometrial epithelial and stromal cells in vivo following natural mating. CD1 mice were naturally mated and sacrificed over the first 4 days post-coitum (n=3 each day). Endometrial epithelial and stromal compartments were isolated by laser capture microdissection. Labelled cRNA was generated and hybridised to genome-wide expression microarrays. Pathway analysis identified several immune-related pathways active within epithelial and stromal compartments, in particular relating to cytokine networks, matrix metalloproteinases and prostaglandin synthesis. Cluster analysis demonstrated that the expression of factors involved in immunomodulation/endometrial remodelling differed between the epithelial and stromal compartments in a temporal fashion. This study is the first to examine the disparate responses of the endometrial epithelial and stromal compartments to seminal plasma in vivo in mice, and demonstrates the complexity of the interactions between these two compartments needed to create a permissive environment for implantation.


Asunto(s)
Endometrio/inmunología , Epitelio/inmunología , Inmunidad/fisiología , Células del Estroma/inmunología , Animales , Citocinas/biosíntesis , Citocinas/genética , Implantación del Embrión/fisiología , Endometrio/citología , Femenino , Expresión Génica/inmunología , Estudio de Asociación del Genoma Completo , Inmunidad/genética , Masculino , Metaloproteinasas de la Matriz/biosíntesis , Metaloproteinasas de la Matriz/genética , Ratones , Análisis por Micromatrices , Microdisección , Embarazo , Prostaglandinas/biosíntesis , ARN Complementario/biosíntesis , ARN Complementario/genética , Semen/metabolismo , Transducción de Señal/genética , Transducción de Señal/inmunología , Útero/citología , Útero/metabolismo
5.
J Skin Cancer ; 2019: 1628247, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31139472

RESUMEN

BACKGROUND: In Blacks, malignant melanoma (MM) is associated with greater morbidity and mortality compared to Caucasians. MMs with BRAF V600E mutation as well as those with loss of p16 protein expression are associated with aggressive behavior and worse prognosis. OBJECTIVES: We determined BRAF (V600E) mutation status and loss of p16 expression in MM cases in Lagos, Nigeria, and correlated these with histopathologic parameters and patients' age. METHODS: Forty-five cases of MM received between January 2005 and December 2014 in the Anatomic and Molecular Pathology Department of Lagos University Teaching Hospital were subjected to immunohistochemical studies to determine BRAF V600E mutation and p16 protein expression. These included cutaneous (n=37), musosal (n=3), and ocular MM (n=2) as well as lymph node metastatases (n=3). RESULTS: BRAF (V600E) mutations were detected in 5/45 (11%) while 31/45 (69%) of the cases had loss of p16 expression. No statistically significant association was found between the BRAF (V600E) mutation, loss of p16 expression, and histologic parameters such as histologic variant, Clark level, Breslow thickness, and ulceration. CONCLUSION: BRAF (V600E) mutation was detected only in a small proportion of cases while loss of p16 expression occurred in most cases which also had high Clark level, high Breslow thickness, and ulceration.

6.
Br J Surg ; 95(1): 50-6, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18027383

RESUMEN

BACKGROUND: Perioperative renal dysfunction following abdominal aortic aneurysm (AAA) repair is multifactorial and may involve hypotension, hypoxia and ischaemia-reperfusion injury. Studies of cardiac and hepatic transplant surgery have demonstrated beneficial effects on renal function of high-dose methylprednisolone administered before surgery. METHODS: Twenty patients undergoing elective open AAA repair were randomized to receive either methylprednisolone 10 mg/kg or dextrose (control) before induction of anaesthesia. Blood was analysed for a panel of cytokines representative of T helper cell type 1 and 2 subsets. Urine was analysed for subclinical markers of renal dysfunction (albumin, alpha(1)-microglobulin and N-acetyl-beta-D-glucosaminidase). RESULTS: Data from 18 patients were analysed. Both groups demonstrated glomerular and proximal convoluted tubular dysfunction that was unaffected by steroid treatment. Steroid administration increased serum levels of urea and creatinine (both P < 0.001). The steroid group had increased interleukin 10 levels (P = 0.005 compared to controls). There were no differences between groups in overall surgical complications, length of intensive care unit (P = 0.821) and hospital (P = 0.719) stay, or 30-day mortality. CONCLUSION: Methylprednisolone administration altered the cytokine profile favourably but adversely affected postoperative renal function.


Asunto(s)
Antiinflamatorios/uso terapéutico , Aneurisma de la Aorta Abdominal/cirugía , Enfermedades Renales/prevención & control , Metilprednisolona/uso terapéutico , Complicaciones Posoperatorias/prevención & control , Cuidados Preoperatorios/métodos , Acetilglucosaminidasa/orina , Anciano , Albuminuria/etiología , alfa-Globulinas/orina , Constricción , Citocinas/metabolismo , Método Doble Ciego , Humanos , Enfermedades Renales/orina , Persona de Mediana Edad , Reoperación , Linfocitos T Colaboradores-Inductores/efectos de los fármacos , Linfocitos T Colaboradores-Inductores/metabolismo
7.
BJOG ; 115(8): 1052-6; discussion 1056, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18651887

RESUMEN

Functional single nucleotide polymorphisms (SNPs) of interleukin (IL)-4 -590 (C>T), toll-like receptor (TLR)-2 +2258 (G>A) and matrix metalloproteinase (MMP)-9 -1562 (C>T) were examined by polymerase chain reaction-restriction fragment length polymorphism to identify their merit as genetic markers for pre-eclampsia. One hundred and seventeen pre-eclamptic women and 146 control subjects with uncomplicated singleton pregnancies participated in this study, conducted at Leeds General Infirmary and St James's University Hospital. While the TLR-2 +2258 (G>A) and MMP-9 -1562 (C>T) SNPs failed to present any significant association with pre-eclampsia, there was a marked trend for an association between the IL-4 -590 (C>T) SNP and pre-eclampsia (chi(2)= 5.87, P = 0.055), with a prevalence of TT homozygous women in this group (OR 4.455, 95% CI 1.286-15.350).


Asunto(s)
Interleucina-4/genética , Metaloproteinasa 9 de la Matriz/genética , Polimorfismo Genético/genética , Preeclampsia/genética , Receptor Toll-Like 2/genética , Adolescente , Adulto , Estudios de Casos y Controles , Femenino , Marcadores Genéticos , Predisposición Genética a la Enfermedad/genética , Humanos , Embarazo
8.
Hypertens Pregnancy ; 27(1): 1-16, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18293200

RESUMEN

The pathophysiology of preeclampsia (PET) implicates an inflammatory dysfunction. This study profiled this host response by challenging whole blood with lipopolysaccharide. Multiplex immunoassays determined interleukin (IL)-1beta, IL-2, IL-4, IL-5, IL-6, IL-7, IL-8, IL-10, IL-12(p70), IL-13, IL-17, granulocyte/granulocyte macrophage-colony stimulating factors (G-CSF/GM-SCF), interferon(IFN)-gamma, monocyte chemotactic protein (MCP)-1, macrophage inflammatory protein-1beta and tumor necrosis factor (TNF)-alpha levels. Secretory capacity was expressed in pg/million white cells or monocytes (+/-SEM). PET featured significantly higher IL-1beta, IL-2, IL-10, IL-13, G-CSF, IFN-gamma, MCP-1 and TNF-alpha monocyte secretory capacities (p < 0.05). The PET group exhibited an inflammatory hyper-responsiveness (p < 0.01) which was poorly described by the traditional Th1:Th2 dichotomy.


Asunto(s)
Citocinas/sangre , Inflamación/sangre , Lipopolisacáridos/sangre , Preeclampsia/fisiopatología , Adolescente , Adulto , Femenino , Humanos , Técnicas In Vitro , Masculino , Modelos Biológicos , Preeclampsia/inmunología , Embarazo
9.
Ann Ig ; 20(1): 77-91, 2008.
Artículo en Italiano | MEDLINE | ID: mdl-18478679

RESUMEN

The Author describes the various phases of the teaching of microbiology in the Faculty of Medicine of the University, of Rome, from the unity of Italy to the end of the twentieth century. A regular course of Bacteriology was started only in the academic year 1905/1906 as separate teaching from that of Hygiene and the Institute of Bacteriology was created in 1924. It was centered in Piazza del Viminale in Rome, in the same building as the Institute of Hygiene. Prof Vittorio Puntoni was the first Director of the Institute, also in its new site of the Città Universitaria which was inaugurated in 1935. In the meantime the old name of Bacteriology was changed to Microbiology and prof Puntoni remained as Director until 1943. The bombing during the war produced heavy damage to the new Institute and with the appointment of prof Aldo Cimmino as a new Director in 1946 the Institute of Microbiology began a long period of reconstruction and development. An astonishing improvement was achieved in the availability of human and technical resources, many groups of research workers were created and several pupils became professor of Microbiology in different Italian Universities. In 1981 prof Cimmino definitely retired, leaving, the teaching of Microbiology in the Faculty of Medicine of the University of Rome "La Sapienza" to five of his pupils. One of them, prof Garaci, a few years later passed to the new University of Rome "Tor Vergata", becoming also Rector. The other four professor (Orsi, Filadoro, Pezzi, del Piano) continued their teaching in the successive years, with the collaboration of several associate professors, whose status was created by the law 382 in 1980. A later law on the short degree course required also the official participation of many researchers to the new teaching. Finally in 2001 the official activity of the Institute of Microbiology ceased and was incorporated in the Department of Public Health Sciences.


Asunto(s)
Academias e Institutos/historia , Microbiología/educación , Microbiología/historia , Facultades de Medicina/historia , Historia del Siglo XIX , Historia del Siglo XX , Ciudad de Roma
10.
Theriogenology ; 67(8): 1409-13, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17420039

RESUMEN

Superovulation is a fundamental procedure for generating transgenic rodents. While various methods exist, zygote yield/quality remain suboptimal, making these techniques open to refinement. All require a follicle stimulating and a luteinising effect. The former can be induced by pregnant mare serum gonadotrophin (PMSG) or other compounds like human menopausal gonadotrophin (HMG). While HMG can double zygote yield compared to PMSG, no study has compared their effects on embryo quality. Embryo yield could also be increased with PMSG: timing administration at estrus may further improve follicular recruitment. This study compared: (i) the efficacy of HMG/PMSG for producing viable embryos for microinjection; and (ii) the effect of HMG/PMSG administration at estrus on embryo yield. Whitten effect-induced estrous C57/Bl6xCBA F(1) hybrid mice were superovulated as follows: PMSG (day 1; 5 IU intraperitoneally) or HMG (days 1 and 2; 1 IU intramuscularly); all received human chorionic gonadotrophin (hCG) on day 3 (5 IU, intraperitoneally). Zygotes were retrieved following mating, morphologically assessed and microinjected with innocuous ZhAT1R construct (expressing LacZ reporter and human angiotensin II type 1 receptor) before transfer to pseudopregnant recipients. Pups were tested for the transgene by Southern blot. Neither HMG nor PMSG proved superior in improving embryo yield, morphology and short-term post-microinjection survival. However, HMG group micromanipulated embryos all failed to establish a pregnancy/generate transgenic pups, unlike their PMSG counterparts. While HMG can be used for superovulation, it appears to increase embryo vulnerability to the long-term effects of microinjection. Furthermore, the embryo yields associated with HMG can be replicated by timing PMSG injection to coincide with Whitten effect-induced estrus.


Asunto(s)
Técnicas de Transferencia de Gen/veterinaria , Gonadotropinas Equinas/administración & dosificación , Menotropinas/administración & dosificación , Ratones Transgénicos , Superovulación , Animales , Southern Blotting , Transferencia de Embrión/veterinaria , Femenino , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos CBA , Microinyecciones/veterinaria , Embarazo , Seudoembarazo/veterinaria , Receptor de Angiotensina Tipo 1/genética , Recolección de Tejidos y Órganos/veterinaria , Transgenes , Cigoto
11.
Anim Reprod Sci ; 96(1-2): 54-65, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16413151

RESUMEN

Cytokines are pleiotropic glycoproteins participating in many aspects of mammalian reproductive physiology. Although murine models have been established to study normal and pathological pregnancy, the small volume of retrievable sample has hampered investigations into the role of cytokines in these processes. These problems were overcome by using fluid-phase multiplex immunoassays to monitor the serum profiles of 18 cytokines in single animals throughout normal murine reproduction: estrus, diestrus, post coitum, preimplantation, implantation, mid-pregnancy, late pregnancy and post partum. Most cytokines were detectable throughout all stages studied. Modest changes in profile were associated with estrous cyclicity and early pregnancy while virtually all cytokine levels increased markedly in mid- to late pregnancy and either fell slightly or levelled off post partum. The functional interrelationships between the various cytokines and the hormonal milieu are discussed with respect to gestational stage. Although certain profiles supported the 'conventional' Th1:Th2 cytokine paradigm of pregnancy, many of the changes recorded were orchestrated around IL-12 (p40) and (p70). The present findings suggest that the traditional cytokine dichotomy poorly describes complex immunological processes like pregnancy.


Asunto(s)
Citocinas/sangre , Ciclo Estral/sangre , Periodo Posparto/sangre , Preñez/sangre , Animales , Quimiocina CXCL1 , Quimiocinas/sangre , Quimiocinas CXC , Femenino , Edad Gestacional , Factor Estimulante de Colonias de Granulocitos/sangre , Inmunoensayo , Interferón gamma/sangre , Interleucina-10/sangre , Interleucina-12/sangre , Interleucinas/sangre , Ratones , Embarazo , Factor de Necrosis Tumoral alfa/análisis
12.
Eur J Obstet Gynecol Reprod Biol ; 197: 130-5, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26745392

RESUMEN

OBJECTIVE: This study aimed to examine the use of digital technology in the three-dimensional reconstruction of human placentas. STUDY DESIGN: Placentas obtained at term elective caesarean section were sampled, formalin-fixed and embedded in paraffin. Two hundred 5 µm consecutive sections were cut from each specimen and the resultant slides stained with haematoxylin and eosin. Slides were then scanned and the digitised images reconstructed using customised software. RESULTS: Three-dimensional reconstructions were successfully achieved in placentas from normal pregnancies and those complicated by pre-eclampsia, growth restriction, and gestational diabetes. Marked morphological differences were readily identifiable, most clearly in the stem villus architecture. CONCLUSION: This method is an emerging research tool for examining placental histoarchitecture at high resolution and gaining clinically relevant insight into the placental pathology allied to pregnancy complications such as PET, IUGR and GD.


Asunto(s)
Vellosidades Coriónicas/patología , Diabetes Gestacional/patología , Retardo del Crecimiento Fetal/patología , Preeclampsia/patología , Estudios de Casos y Controles , Cesárea , Femenino , Humanos , Imagenología Tridimensional , Proyectos Piloto , Placenta/patología , Embarazo
13.
Antiviral Res ; 10(1-3): 117-27, 1988 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2852916

RESUMEN

The effect of newly synthesized halogenated isoflavans and isoflavenes on human rhinovirus 1B (HRV 1B) infection of HeLa cells has been examined. Both series of drugs inhibited virus plaque formation in cell cultures, isoflavans being more effective than isoflavenes. Cells pretreated with compounds before challenge with HRV 1B became resistant to the virus-induced cytopathic effect. The antiviral state induced by the most active compounds persisted for at least 10 h and did not appear to be mediated by interferon production. Experiments whereby the compounds were added at varying times indicated that the isoflavans and isoflavenes interfere with early events of virus replication without affecting virus binding to the cell membrane. In addition to their effects on virus multiplication, the isoflavans were also found to have a direct action on the virus. The inhibitory effect on virus infectivity required extraction with chloroform for reversal. Isoflavans also protected the virions against mild acid or heat inactivation.


Asunto(s)
Flavonoides/farmacología , Isoflavonas/farmacología , Rhinovirus/efectos de los fármacos , Replicación Viral/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células HeLa , Humanos , Rhinovirus/crecimiento & desarrollo , Rhinovirus/patogenicidad , Ensayo de Placa Viral
14.
Antiviral Res ; 11(5-6): 247-54, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2552913

RESUMEN

The effect of 6,4'-dichloroflavan and of isoflavan and isoflavene derivatives on hepatitis A virus (HAV) infection in a monkey cell line (Frp/3 cells) was studied. These compounds were not virucidal and had no measurable effect on the adsorption of virus to the cells at 0 degrees C, whereas they exerted an inhibitory effect on viral antigen synthesis when incubated with the infected cells during HAV multiplication. Among the substances tested, 6,4'-dichloroflavan and 6,4'-dichloroisoflavan showed the highest activity. These compounds are postulated to interact with an early stage (penetration and/or uncoating) of HAV infection.


Asunto(s)
Antivirales , Flavonoides/farmacología , Hepatovirus/efectos de los fármacos , Línea Celular , Relación Dosis-Respuesta a Droga , Técnica del Anticuerpo Fluorescente , Humanos , Estructura Molecular , Replicación Viral/efectos de los fármacos
15.
Antiviral Res ; 13(4): 201-8, 1990 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2116755

RESUMEN

In this study we investigated the activity of halogeno-, cyano- and amidino-isoflavenes, isoflavans and flavans on the multiplication of human astroviruses. These are naked small round viruses which have been recognized as causative agents of human gastroenteritis, and whose capsid proteins are similar to those of picornaviruses. Although all drugs tested caused a dose-dependent reduction of viral antigen synthesis as monitored by immunofluorescence, the chloro derivatives were the most effective.


Asunto(s)
Antivirales/farmacología , Flavonoides/farmacología , Isoflavonas/farmacología , Mamastrovirus/efectos de los fármacos , Virosis/tratamiento farmacológico , Virus no Clasificados/efectos de los fármacos , Animales , Antígenos Virales/inmunología , Línea Celular , Técnica del Anticuerpo Fluorescente , Mamastrovirus/crecimiento & desarrollo , Mamastrovirus/inmunología , Conejos
16.
FEMS Microbiol Lett ; 63(2-3): 225-31, 1991 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-1829423

RESUMEN

A total of 230 Salmonella strains were screened for enterobactin and aerobactin production, sensitivity to bacteriocins and resistance to antibiotics. All the isolates produced the phenolate siderophore enterobactin. Amongst these, 74 strains, most belonging to S. enteritidis, were sensitive to colicin B. Only 26 isolates, all belonging to S. wien, produced an additional iron chelator, i.e. the siderophore aerobactin, and 22 out of these were sensitive to cloacin DF13. Analysis of iron repressible outer membrane proteins and plasmid profiles in S. wien strains showed that the expression of a 74-kDa iron-repressible outer membrane protein and the presence of large plasmids were associated with multiple antibiotic resistance, aerobactin production and sensitivity to cloacin DF13. The incidence of aerobactin-producing strains among S. wien isolates was higher during years 1974-1985; the epidemiological implications of these results are discussed.


Asunto(s)
Enterobactina/metabolismo , Ácidos Hidroxámicos/metabolismo , Salmonella/metabolismo , Proteínas de la Membrana Bacteriana Externa/análisis , Bioensayo , Cloacina/farmacología , Colicinas/farmacología , Farmacorresistencia Microbiana , Electroforesis en Gel de Poliacrilamida , Heces/microbiología , Microbiología de Alimentos , Humanos , Italia , Plásmidos , Salmonella/clasificación , Salmonella/efectos de los fármacos , Salmonella/genética
17.
J Med Microbiol ; 34(2): 113-8, 1991 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-1824950

RESUMEN

The growth inhibiting activity of transferrins, citrate, 2-2' dipyridyl and desferrioxamine methanesulphonate towards Legionella spp. and their serogroups was investigated. The inhibitory activity of all these compounds depended upon the iron-free state of the molecules and was abolished by saturation with iron. No bactericidal effect by transferrins was observed at concentrations up to four times the minimal bacteriostatic concentration. No interaction of transferrins with the legionella cell surface was detected by direct or indirect fluorescence assay, or by dialysis culture experiments in which transferrin was separated from the bacterial cells. The demonstration of a siderophore-like activity in supernates of iron-deficient legionella cultures may account for the ability of Legionella spp. to multiply in conditions of iron restriction.


Asunto(s)
Quelantes/farmacología , Legionella/crecimiento & desarrollo , 2,2'-Dipiridil/farmacología , Citratos/farmacología , Ácido Cítrico , Medios de Cultivo , Deferoxamina/farmacología , Hierro/metabolismo , Quelantes del Hierro/metabolismo , Legionella/efectos de los fármacos , Sideróforos , Transferrina/farmacología
18.
J Med Microbiol ; 42(4): 269-75, 1995 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7707335

RESUMEN

The polyether antibiotic monensin exhibited bacteriostatic activity against a clinical isolate of Legionella pneumophila in vitro. Experiments designed to test the effect of the compound on the invasiveness and multiplication of L. pneumophila in HeLa cells showed that, in the presence of the antibiotic, legionellas that penetrated the cells did not multiply. However, monensin did not alter the characteristics of phagosomes that contained ingested legionellas. In the presence of monensin, infected cells exhibited extensive vacuolation and a noticeable reduction in the number of intracellular micro-organisms was evident a few hours after infection.


Asunto(s)
Legionella pneumophila/efectos de los fármacos , Monensina/farmacología , Células HeLa , Humanos , Legionella pneumophila/crecimiento & desarrollo , Legionella pneumophila/fisiología , Legionella pneumophila/ultraestructura , Microscopía Electrónica
19.
J Hosp Infect ; 19(3): 153-65, 1991 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1685503

RESUMEN

One hundred and twenty-one clinical isolates of Pseudomonas aeruginosa from patients with hospital-acquired urinary tract infections (UTIs) were studied to determine their major epidemiological markers, including API 20NE profile, O-serotype, pyocin type, phage type, lysogenic state and antibiotic susceptibility. Serotypes O4, O12, O11, O6 and O5 were found with a high frequency, accounting respectively for 23.9%, 23.1%, 12.3%, 8.2% and 5.7% of isolates. Pyocin type 10 was most common (32.2%) followed by types 1 (10.7%), 33 (7.5%) and 105 (4.1%); subtype h was predominant being characteristic of 34.7% of isolates. Most of the strains (69.4%) were either not phage typable or sensitive to phages 68 and 119x. Resistance to gentamicin, tobramycin, amikacin, imipenem and ciprofloxacin was more frequent among strains belonging to serotype O12. The O-serotypes were combined with API 20NE profiles, pyocin and phage types, lysogenic states and antibiotic resistance in order to identify epidemiologically related clones. Within predominant serotypes--O4 and O12--most strains displayed similar but not identical type characteristics, whereas other serotypes were less homogeneous. Our results support the concept that a combination of current typing techniques allows the identification of epidemiologically related P. aeruginosa isolates.


Asunto(s)
Técnicas de Tipificación Bacteriana , Pseudomonas aeruginosa/clasificación , Tipificación de Bacteriófagos , Infección Hospitalaria/microbiología , Humanos , Pruebas de Sensibilidad Microbiana , Infecciones por Pseudomonas/microbiología , Pseudomonas aeruginosa/aislamiento & purificación , Piocinas/clasificación , Piocinas/aislamiento & purificación , Serotipificación , Infecciones Urinarias/microbiología
20.
Int J Biol Markers ; 10(1): 11-6, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-7629421

RESUMEN

DNA content was determined by flow cytometry in a series of 51 paired fresh tissue samples of primary colorectal carcinomas and the respective non-neoplastic adjacent mucosa in order to assess the relationship between DNA ploidy and the most commonly used prognostic factors. Aneuploidy was observed in 70.6% of the tumors and more than one aneuploid peak was present in 3.9%. Aneuploid tumor frequency was higher in left (93.3%) and right colon (64.7%) cancers than in rectal carcinomas (60.0%), and multiple aneuploid clones were detected more frequently in men than in women and in patients with advanced disease (Dukes stage D). Non-neoplastic mucosa adjacent to aneuploid tumors showed aneuploidy in 4 out of 51 samples (7.8%). The mucosa adjacent to diploid cancers had only diploid characteristics. Ploidy did not correlate with histological abnormalities. These findings suggest that DNA content as determined by flow cytometry needs further study with adequate follow-up to evaluate possible correlations with relapse-free and overall survival. Furthermore the aneuploidy of non-neoplastic mucosa provides evidence for a field defect in mucosa adjacent to colorectal cancer and supports the concept that this alteration may be of influence on carcinogenesis.


Asunto(s)
Adenocarcinoma/genética , Aneuploidia , Neoplasias Colorrectales/genética , ADN de Neoplasias/análisis , Mucosa Intestinal/química , Adenocarcinoma/patología , Adenocarcinoma Mucinoso/genética , Adenocarcinoma Mucinoso/patología , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias Colorrectales/patología , Femenino , Citometría de Flujo , Humanos , Mucosa Intestinal/citología , Masculino , Persona de Mediana Edad , Pronóstico , Factores Sexuales
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