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1.
Mucosal Immunol ; 11(3): 846-860, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29186109

RESUMEN

CD44 is a transmembrane molecule appearing in numerous isoforms generated by insertions of alternatively spliced variant exons (CD44v) and having various binding partners. CD44v7 on T cells was proposed to promote colitis by preventing T-cell apoptosis. Here we demonstrate that Cd44v7-deficient T cells - like Cd44 wild-type (Cd44WT) T cells - provoked disease in two different colitis models: the model induced by CD4+CD45RBhigh T-cell transfer into Rag2-deficient mice and a new model based on ovalbumin (OVA)-specific T-cell transfer into Rag-sufficient, OVA-challenged mice. In contrast, CD44v7 absence on macrophages in recipient mice prevented colitis. Prevention was associated with the downregulation of signal transducer and activator of transcription 3 (STAT3)-activating and Foxp3-counteracting interleukin-6 (IL-6), lower numbers of phospho-STAT3-containing lymphocytes, and higher Foxp3+ T-cell counts in the colon. Consequently, the protected colons showed lower IL-12, IL-1ß expression, and decreased interferon-γ levels. Importantly, stimulation of T cells by Cd44v7-deficient macrophages induced upregulation of Foxp3 in vitro, while cotransfer of Cd44WT macrophages into Cd44v7-deficient mice reduced Foxp3+ T-cell counts and caused colitis. Accordingly, the CD44v7 ligand osteopontin, whose levels were elevated in Crohn's disease, specifically induced IL-6 in human monocytes, a cytokine also increased in these patients. We suggest macrophage-specific targeting of the CD44v7 pathway as a novel therapeutic option for Crohn's disease.


Asunto(s)
Colitis/inmunología , Enfermedad de Crohn/inmunología , Receptores de Hialuranos/metabolismo , Macrófagos/fisiología , Subgrupos de Linfocitos T/fisiología , Linfocitos T Reguladores/fisiología , Adulto , Empalme Alternativo , Animales , Células Cultivadas , Técnicas de Cocultivo , Citocinas/metabolismo , Modelos Animales de Enfermedad , Exones/genética , Femenino , Factores de Transcripción Forkhead/metabolismo , Humanos , Receptores de Hialuranos/genética , Mediadores de Inflamación/metabolismo , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Noqueados , Ratones Transgénicos , Osteopontina/metabolismo
2.
Oncogene ; 36(46): 6446-6461, 2017 11 16.
Artículo en Inglés | MEDLINE | ID: mdl-28759043

RESUMEN

The majority of long noncoding RNAs (lncRNAs) is still poorly characterized with respect to function, interactions with protein-coding genes, and mechanisms that regulate their expression. As for protein-coding RNAs, epigenetic deregulation of lncRNA expression by alterations in DNA methylation might contribute to carcinogenesis. To provide genome-wide information on lncRNAs aberrantly methylated in breast cancer we profiled tumors of the C3(1) SV40TAg mouse model by MCIp-seq (Methylated CpG Immunoprecipitation followed by sequencing). This approach detected 69 lncRNAs differentially methylated between tumor tissue and normal mammary glands, with 26 located in antisense orientation of a protein-coding gene. One of the hypomethylated lncRNAs, 1810019D21Rik (now called Esrp2-antisense (as)) was identified in proximity to the epithelial splicing regulatory protein 2 (Esrp2) that is significantly elevated in C3(1) tumors. ESRPs were shown previously to have a dual role in carcinogenesis. Both gain and loss have been associated with poor prognosis in human cancers, but the mechanisms regulating expression are not known. In-depth analyses indicate that coordinate overexpression of Esrp2 and Esrp2-as inversely correlates with DNA methylation. Luciferase reporter gene assays support co-expression of Esrp2 and the major short Esrp2-as variant from a bidirectional promoter, and transcriptional regulation by methylation of a proximal enhancer. Ultimately, this enhancer-based regulatory mechanism provides a novel explanation for tissue-specific expression differences and upregulation of Esrp2 during carcinogenesis. Knockdown of Esrp2-as reduced Esrp2 protein levels without affecting mRNA expression and resulted in an altered transcriptional profile associated with extracellular matrix (ECM), cell motility and reduced proliferation, whereas overexpression enhanced proliferation. Our findings not only hold true for the murine tumor model, but led to the identification of an unannotated human homolog of Esrp2-as which is significantly upregulated in human breast cancer and associated with poor prognosis.


Asunto(s)
Metilación de ADN , Estudio de Asociación del Genoma Completo/métodos , Neoplasias Mamarias Experimentales/genética , ARN Largo no Codificante/genética , Células 3T3-L1 , Animales , Antígenos Virales de Tumores/genética , Western Blotting , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/genética , Línea Celular Tumoral , Modelos Animales de Enfermedad , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Mamarias Experimentales/diagnóstico , Ratones , Ratones Transgénicos , Pronóstico , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo , Análisis de Supervivencia
4.
J Clin Microbiol ; 54(3): 812-4, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26763960

RESUMEN

Using blaZ PCR as the "gold standard," the sensitivities of CLSI penicillin zone edge and nitrocefin-based tests for ß-lactamase production in Staphylococcus aureus were 64.5% and 35.5%, respectively, with specificity of 99.8% for both methods. In 2013, 13.5% of 3,083 S. aureus isolates from 31 U.S. centers were penicillin susceptible.


Asunto(s)
Resistencia a las Penicilinas , Penicilinas/farmacología , Infecciones Estafilocócicas/epidemiología , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/efectos de los fármacos , Genes Bacterianos , Humanos , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Prevalencia , Estados Unidos/epidemiología
5.
Fortschr Neurol Psychiatr ; 83(7): 381-91, 2015 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-26200043

RESUMEN

Late life depression is associated with severe health consequences, e.g. elevated risk of medical comorbidity and decreased quality of life. This paper summarizes the recommendations of the international guidelines on evidence-based pharmacological treatment of depression in late life in a systematic review. Pharmacological treatments for depression recommended by most of the guidelines, however, hardly address the issue of the possible side effects of antidepressants and other factors of multi-medication on the elderly. Different guidelines pay different degrees of attention to the specific group of geriatric patients. There is a lack of evidence-based treatment recommendation that takes into consideration the specific age-related issues of sensitivity to adverse effects or pharmacokinetic interaction. Further research is required to provide a database for more refined recommendations in guidelines.


Asunto(s)
Antidepresivos/uso terapéutico , Depresión/tratamiento farmacológico , Psiquiatría Geriátrica/tendencias , Anciano , Anciano de 80 o más Años , Guías como Asunto , Humanos
6.
Eur J Microbiol Immunol (Bp) ; 2(3): 192-200, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24688765

RESUMEN

In experimental models of and humans with intestinal inflammation, increased levels of the matrix-degrading gelatinases MMP-2 and -9 in inflamed tissues can be detected. The synthetic collagen analogue (Gly-Pro-Hyp)10, (GPO)10, has been identified as a relevant binding structure for proMMP-2/-9 and promotes enzymatic activity of proMMP-2. Since targeted MMP strategies might offer promising anti-inflammatory treatment options, we for the first time studied in vivo actions exerted by (GPO)10 applying an acute dextrane sulfate sodium (DSS) induced colitis model. Seven-day intraperitoneal (GPO)10 treatment ameliorated clinical symptoms and histopathological colonic changes as compared to placebo controls with severe colitis. (GPO)10-treated mice displayed a diminished influx of neutrophils, and T- and B-lymphocytes into their colonic mucosa whereas numbers of regulatory T-cells and regenerative cells were higher as compared to placebo controls. Furthermore, IL-6 secretion was down-regulated in ex vivo colonic biopsies derived from (GPO)10-treated mice whereas higher concentrations of the anti-inflammatory cytokine IL-10 in extra-intestinal compartments such as MLN and spleen could be detected. Strikingly, influx of inflammatory cells into lungs was abolished following (GPO)10 application. We therefore propose (GPO)10 as a promising effective and safe treatment option of intestinal and extra-intestinal inflammatory conditions in humans.

7.
Eur J Microbiol Immunol (Bp) ; 2(3): 231-8, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24688770

RESUMEN

Viral proteins are highly antigenic and known as potent stimulators of adaptive immune responses. This mechanism is often used for biotechnological applications in monoclonal antibody production resulting in high-affinity IgG antibodies in most cases. The aim of this study was to increase antigen-specific IgA antibody levels in mice in order to generate monoclonal IgA antibodies by hybridoma technology. For this purpose, hamster polyomavirus (HaPyV) major capsid protein VP1 was used to immunize mice by different routes in order to induce VP1-specific IgA titers. Recombinant HaPyV-VP1 was generated in Escherichia coli and administered intraperitoneally, orally, and intrarectally. VP1-specific antibodies were determined by ELISA in sera and organ culture supernatants. We found a significant increase of HaPyV-VP1-specific IgAs in spleen organ cultures after rectal immunization of mice but not in cultures of mesenteric lymph nodes, colon, or Peyer's patches. In contrast, oral and intraperitoneal immunization did not provide an appropriate specific IgA induction at all. These results show that specific IgA antibodies can be induced by intrarectal immunization in the spleen. The generation of monoclonal IgA antibodies with well-defined properties is a useful tool for the investigation of mucosal immune responses or autoimmune diseases and extends the spectrum of antibodies with specific effector functions.

8.
J Clin Microbiol ; 49(8): 2884-6, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21697321

RESUMEN

Constitutive or inducible clindamycin resistance can occur in beta-hemolytic streptococci due to the presence of an erm gene. The Clinical and Laboratory Standards Institute (CLSI) has recommended a disk approximation test (D-zone test) with erythromycin and clindamycin disks and a single-well broth test combining erythromycin and clindamycin for detection of inducible clindamycin resistance in staphylococci, but only a disk approximation test for the beta-hemolytic streptococci. This collaborative study assessed two different erythromycin and clindamycin concentration combinations in single wells (1 µg/ml + 0.25 µg/ml [erythromycin plus clindamycin] and 1 µg/ml + 0.5 µg/ml) with three different brands of Mueller-Hinton broth supplemented with 3% lysed horse blood for testing of frozen panels prepared for this study. All labs performed the D-zone test as described by the CLSI. A total of 155 nonduplicate streptococcal isolates (50 group A, 48 group B, 28 group C, and 29 group G isolates) were tested; 99 isolates showed inducible resistance by the D-zone test. There were some differences noted based upon the test medium. The sensitivity of the erythromycin plus clindamycin combination of 1 µg/ml + 0.25 µg/ml was 91 to 100%, while the sensitivity of the combination of 1 µg/ml + 0.5 µg/ml was 95 to 100%. Specificity overall was 98%. The slightly higher sensitivity of the combination of 1 µg/ml + 0.5 µg/ml is recommended. This study has demonstrated that a single-well microdilution test incorporating erythromycin and clindamycin in combination is a sensitive and specific indicator of inducible clindamycin resistance and could be included in routine test panels.


Asunto(s)
Antibacterianos/farmacología , Clindamicina/farmacología , Farmacorresistencia Bacteriana , Eritromicina/farmacología , Streptococcus/efectos de los fármacos , Activación Transcripcional , Antibacterianos/metabolismo , Clindamicina/metabolismo , Medios de Cultivo/química , Eritromicina/metabolismo , Pruebas de Sensibilidad Microbiana/métodos , Sensibilidad y Especificidad
9.
Eur J Clin Microbiol Infect Dis ; 26(7): 485-90, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17551759

RESUMEN

The study presented here determined the relationship between antimicrobial resistance in Streptococcus pneumoniae and the use of antimicrobial agents in 15 different European countries. Pneumococcal isolates (n = 1974) recovered from patients with community-acquired respiratory tract infections during the winter of 2004-2005 in 15 European countries were characterized. The overall percentages of isolates demonstrating intermediate or complete resistance to penicillin, erythromycin, tetracycline, trimethoprim-sulfamethoxazole (TMP-SMX) and ciprofloxacin were 24, 24.6, 19.8, 26.7 and 2%, respectively, as determined using the broth microdilution MIC method recommended by the Clinical and Laboratory Standards Institute. The overall and mean antimicrobial consumption levels (ACL)--i.e., the defined daily doses per 1,000 inhabitants per day--were obtained from the European Surveillance of Antimicrobial Consumption project for each of the 15 countries for the years 1998-2004. Using linear regression analysis, the mean annual ACL for beta-lactams, macrolides, tetracyclines, TMP-SMX and fluoroquinolones in each country was compared to the country-specific resistance rates determined in 2004-2005. The rate of overall antimicrobial use in all 15 European countries was significantly associated with antimicrobial resistance in S. pneumoniae. There was variation among the different antimicrobial classes as drivers of resistance, with beta-lactams having the strongest association.


Asunto(s)
Antibacterianos/uso terapéutico , Farmacorresistencia Bacteriana Múltiple , Pautas de la Práctica en Medicina/estadística & datos numéricos , Streptococcus pneumoniae/efectos de los fármacos , Europa (Continente)/epidemiología , Humanos , Infecciones Estafilocócicas/tratamiento farmacológico
10.
Cell Death Differ ; 14(8): 1542-51, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17479111

RESUMEN

Deletion of exon CD44v7 abrogates experimental colitis by apoptosis induction in intestinal mononuclear cells. Here we show that CD44v7 expression was upregulated upon CD40 ligation in human mononuclear cells, and examined whether ligation of CD44v7 also affects activation and apoptosis in lamina propria mononuclear cells (LPMC) from Crohn's disease (CD) patients. Thirty five patients with chronic inflammatory bowel disease (IBD), fourteen controls and four patients with diverticulitis were evaluated. CD44v7 was upregulated predominantly in the inflamed mucosa of CD patients. Furthermore, incubation with an anti-CD44v7 antibody induced apoptosis in LPMC isolated from inflamed mucosa of CD patients, but not from non-inflamed mucosa, from patients with ulcerative colitis (UC) or from normal controls. CD40 ligation and simultaneous incubation with anti-CD44v7 significantly downregulated CD80 in dendritic cells, thus inhibiting a critical second signal for naive T-cell activation. The apoptotic signal was mediated via the intrinsic mitochondrial pathway with decreased Bcl-2 and increased 7A6 (a mitochondrial membrane protein) expression. It was Fas independent and required caspases-3 and -9 activation. The process is highly specific for macrophage activation via CD40. These findings point to a novel mechanism of apoptosis induction in CD patients mediated by CD44v7 ligation.


Asunto(s)
Apoptosis/inmunología , Enfermedad de Crohn/inmunología , Enfermedad de Crohn/patología , Receptores de Hialuranos/metabolismo , Adolescente , Adulto , Animales , Antígenos CD40/metabolismo , Estudios de Casos y Controles , Enfermedad de Crohn/genética , Femenino , Humanos , Receptores de Hialuranos/genética , Leucocitos Mononucleares/inmunología , Leucocitos Mononucleares/patología , Activación de Linfocitos , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos MRL lpr , Ratones Noqueados , Persona de Mediana Edad , Mitocondrias/inmunología , Membrana Mucosa/inmunología , Membrana Mucosa/patología , Transducción de Señal , Linfocitos T/inmunología , Regulación hacia Arriba
11.
Eur J Clin Microbiol Infect Dis ; 25(5): 335-9, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16612609

RESUMEN

The objective of the case-control study presented here was to examine the risk factors for macrolide-resistant Streptococcus pneumoniae. As part of a 44-center U.S. surveillance study, 1,817 unique isolates of S. pneumoniae were collected from November 2002 through April 2003. Seventy-five randomly selected macrolide-resistant isolates (cases) were each matched with one susceptible control. Macrolide use in the 6 weeks prior to sample collection was reported for seven cases and one control. The final conditional logistic regression model identified two statistically significant variables: a history of alcohol abuse was protective, while macrolide use in the 6 weeks prior to sample collection was a significant risk factor for macrolide-resistant S. pneumoniae. Macrolide resistance was associated with use of any antibiotic during the prior 6 weeks, and was most strongly associated with previous macrolide use.


Asunto(s)
Antibacterianos/uso terapéutico , Macrólidos/uso terapéutico , Infecciones Neumocócicas/tratamiento farmacológico , Streptococcus pneumoniae/efectos de los fármacos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antibacterianos/efectos adversos , Estudios de Casos y Controles , Niño , Preescolar , Farmacorresistencia Bacteriana , Eritromicina/farmacología , Femenino , Humanos , Lactante , Recién Nacido , Macrólidos/efectos adversos , Masculino , Persona de Mediana Edad , Infecciones Neumocócicas/microbiología , Streptococcus pneumoniae/aislamiento & purificación
12.
J Biotechnol ; 115(3): 291-301, 2005 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-15639091

RESUMEN

The multiplication and antibody production of murine hybridoma cells cultured on five different polymer membranes were tested and compared with conventional tissue culture polystyrene (TCPS). Membranes were prepared from polyacrylonitrile (PAN) and acrylonitrile copolymerized with N-vinylpyrrolidone (NVP20, NVP30), Na-methallylsulfonate (NaMAS) and N-(3-amino-propyl-methacrylamide-hydrochloride) (APMA). Cell number and antibody concentration were quantified as criteria for viability and productivity. Adhesion of hybridoma cells was characterized by vital and scanning electron microscopy. The results suggest that a strong adhesion of cells, observed on APMA and TCPS, increased cell growth but reduced monoclonal antibody production. In contrast membranes with lowered adhesivity such as NVP20 provided favourable conditions for monoclonal antibody production. In addition it was shown that this membrane also possessed a minor fouling as indicated by the low decrease of water flux across the membrane after protein adsorption. It was concluded that NVP20 could be a suitable material for the development of hollow fibre membranes for bioreactors.


Asunto(s)
Anticuerpos Monoclonales/biosíntesis , Reactores Biológicos , Técnicas de Cultivo de Célula/métodos , Medios de Cultivo/metabolismo , Hibridomas/citología , Hibridomas/fisiología , Animales , Anticuerpos Monoclonales/inmunología , Línea Celular , Proliferación Celular , Inmunoglobulina G/inmunología , Membranas Artificiales , Ratones
13.
Clin Infect Dis ; 40(2): 225-35, 2005 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-15655739

RESUMEN

BACKGROUND: The purpose of this study was to determine the prevalence of fluoroquinolone resistance and quinolone resistance-determining region (QRDR) mutations among Streptococcus pneumoniae isolates in the United States during the period of 2001-2002. A second objective was to examine the genetic relatedness of pneumococcal isolates with parC and/or gyrA mutations during the period of 1994-2002. METHODS: Susceptibility testing was performed for 1902 S. pneumoniae isolates collected in the United States during the period of 2001-2002. On the basis of the minimum inhibitory concentration (MIC) of ciprofloxacin, 146 isolates were selected from the 2001-2002 study for QRDR analysis of parC, parE, gyrA, and gyrB genes. The genetic relatedness of isolates with parC and/or gyrA mutations from 2001-2002 (n=55) and from 3 US surveillance studies conducted during 1994-2000 (n=56) was determined by pulsed-field gel electrophoresis (PFGE). RESULTS: Between 1999-2000 and 2001-2002, there was a 2-fold increase in the rate of ciprofloxacin resistance (MIC, >or=4 micro g/mL), from 1.2% to 2.7%, and in the rate of levofloxacin nonsusceptibility (MIC, >or=4 micro g/mL), from 0.6% to 1.3%. The 111 isolates with parC and/or gyrA mutations were assigned to 48 different PFGE types. Forty-four isolates (40%) belonged to 8 PFGE types that were closely related to widespread clones. Fifteen of the 43 levofloxacin-nonsusceptible pneumococci (LNSP) belonged to 4 PFGE types that were closely related to major clones (Spain(23F)-1 [n=6]; Spain(6B)-2 [n=5], Taiwan(19F)-14 [n=2], and Tennessee(23F)-4 [n=2]). CONCLUSION: The population of fluoroquinolone-resistant S. pneumoniae in the United States has increased but remains genetically diverse. However, 35% of LNSP were related to widespread pneumococcal clones, increasing the potential for the rapid spread of quinolone resistance in this species.


Asunto(s)
Ciprofloxacina/farmacología , Farmacorresistencia Bacteriana , Levofloxacino , Ofloxacino/farmacología , Infecciones Neumocócicas/microbiología , Streptococcus pneumoniae/efectos de los fármacos , Antibacterianos/farmacología , Girasa de ADN/genética , Topoisomerasa de ADN IV/genética , Humanos , Pruebas de Sensibilidad Microbiana , Mutación , Infecciones Neumocócicas/tratamiento farmacológico , Infecciones Neumocócicas/epidemiología , Vigilancia de la Población , Serotipificación , Streptococcus pneumoniae/genética , Factores de Tiempo , Estados Unidos
14.
J Antimicrob Chemother ; 52(1): 123-7, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12805265

RESUMEN

OBJECTIVE: The purpose of this study was to examine the in vitro activity of daptomycin using an optimal calcium (Ca2+) concentration (50 mg/L) against a diverse collection of enterococcal and Staphylococcus aureus clinical isolates, including glycopeptide-resistant enterococci (GRE) and methicillin-resistant S. aureus (MRSA). METHODS: The activity of daptomycin was compared with the activities of seven other agents against 1483 enterococcal and S. aureus clinical isolates, including 303 GRE and 193 methicillin-resistant S. aureus (MRSA) strains. Susceptibility testing was performed by the NCCLS broth microdilution method, with one exception: Mueller-Hinton (MH) broth was supplemented to a physiological level of 50 mg/L Ca2+ when testing daptomycin. Daptomycin zone diameters were determined by disc diffusion with MH agar plates containing Ca2+ 50 mg/L. RESULTS: All staphylococcal isolates tested, and the majority of enterococcal isolates (96.5%), would be considered susceptible to daptomycin if the breakpoint previously proposed of or = 20 mm, and all of the enterococcal isolates had daptomycin zone diameters > or = 17 mm. CONCLUSIONS: Overall, daptomycin showed potent activity against S. aureus and enterococcal isolates, comparable to quinupristin-dalfopristin and linezolid.


Asunto(s)
Antibacterianos/farmacología , Daptomicina/farmacología , Enterococcus faecium/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Calcio/farmacología , Medios de Cultivo , Farmacorresistencia Bacteriana Múltiple , Resistencia a la Meticilina , Pruebas de Sensibilidad Microbiana
15.
Clin Infect Dis ; 34(3): 330-9, 2002 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-11774080

RESUMEN

The genetic relatedness of 672 penicillin-resistant isolates of Streptococcus pneumoniae (PRSP) recovered during national surveillance studies conducted in the United States during the periods of 1994-1995, 1997-1998, and 1999-2000 was determined by use of pulsed-field gel electrophoresis (PFGE). Overall, 104 different PFGE types were elucidated. For all study periods combined, the 12 most prevalent PFGE types included >75% of all isolates, and 5 types were closely related to widespread clones (Spain(23F)-1, France(9V)-3, Spain(6B)-2, Tennessee(23F)-4, and Taiwan(19F)-14). From 1994-1995 to 1999-2000, 3 major PFGE types (not closely related to 16 recognized clones) increased in prevalence. Multidrug resistance was identified among 96%-100% of the isolates in 9 of 12 predominant PFGE types. The prevalence of erythromycin resistance increased within 4 major PFGE types. These observations support the hypothesis that the dominant factor in the emergence of PRSP in the United States during the 1990s has been human-to-human spread of relatively few clonal groups that harbor resistance determinants to multiple classes of antibiotics.


Asunto(s)
Resistencia a las Penicilinas/genética , Streptococcus pneumoniae/genética , Adolescente , Adulto , Antibacterianos/farmacología , Niño , Electroforesis en Gel de Campo Pulsado , Eritromicina/farmacología , Frecuencia de los Genes , Humanos , Pruebas de Sensibilidad Microbiana , Neumonía Neumocócica/epidemiología , Neumonía Neumocócica/microbiología , Estaciones del Año , Serotipificación , Streptococcus pneumoniae/efectos de los fármacos , Estados Unidos/epidemiología
16.
Antimicrob Agents Chemother ; 45(6): 1721-9, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11353617

RESUMEN

A total of 1,531 recent clinical isolates of Streptococcus pneumoniae were collected from 33 medical centers nationwide during the winter of 1999--2000 and characterized at a central laboratory. Of these isolates, 34.2% were penicillin nonsusceptible (MIC > or = 0.12 microg/ml) and 21.5% were high-level resistant (MIC > or = 2 microg/ml). MICs to all beta-lactam antimicrobials increased as penicillin MICs increased. Resistance rates among non-beta-lactam agents were the following: macrolides, 25.2 to 25.7%; clindamycin, 8.9%; tetracycline, 16.3%; chloramphenicol, 8.3%; and trimethoprim-sulfamethoxazole (TMP-SMX), 30.3%. Resistance to non-beta-lactam agents was higher among penicillin-resistant strains than penicillin-susceptible strains; 22.4% of S. pneumoniae were multiresistant. Resistance to vancomycin and quinupristin-dalfopristin was not detected. Resistance to rifampin was 0.1%. Testing of seven fluoroquinolones resulted in the following rank order of in vitro activity: gemifloxacin > sitafloxacin > moxifloxacin > gatifloxacin > levofloxacin = ciprofloxacin > ofloxacin. For 1.4% of strains, ciprofloxacin MICs were > or = 4 microg/ml. The MIC(90)s (MICs at which 90% of isolates were inhibited) of two ketolides were 0.06 microg/ml (ABT773) and 0.12 microg/ml (telithromycin). The MIC(90) of linezolid was 2 microg/ml. Overall, antimicrobial resistance was highest among middle ear fluid and sinus isolates of S. pneumoniae; lowest resistance rates were noted with isolates from cerebrospinal fluid and blood. Resistant isolates were most often recovered from children 0 to 5 years of age and from patients in the southeastern United States. This study represents a continuation of two previous national studies, one in 1994--1995 and the other in 1997--1998. Resistance rates with S. pneumoniae have increased markedly in the United States during the past 5 years. Increases in resistance from 1994--1995 to 1999--2000 for selected antimicrobial agents were as follows: penicillin, 10.6%; erythromycin, 16.1%; tetracycline, 9.0%; TMP-SMX, 9.1%; and chloramphenicol, 4.0%, the increase in multiresistance was 13.3%. Despite awareness and prevention efforts, antimicrobial resistance with S. pneumoniae continues to increase in the United States.


Asunto(s)
Resistencia a Múltiples Medicamentos , Pruebas de Sensibilidad Microbiana , Resistencia a las Penicilinas , Streptococcus pneumoniae/efectos de los fármacos , Adulto , Anciano , Niño , Humanos , Lactante , Vigilancia de Guardia , Streptococcus pneumoniae/aislamiento & purificación , Estados Unidos
17.
Pathologe ; 18(3): 228-32, 1997 May.
Artículo en Alemán | MEDLINE | ID: mdl-9273540

RESUMEN

A total of 334 hyperplastic polyps of the colon of 266 patients were examined under epidemiologically, morphometrically and histochemically. Of these, 62 cases (23%) were associated with adenomas, 18 cases (7%) with carcinomas. Hyperplastic polyps are not entirely homogeneous, pathologically and -anatomically: Carcinoma-associated hyperplastic polyps are larger in diameter, the size and width of their crypts is greater, and they have a higher percentage of goblet cells with a higher amount of sialomucins as shown by HID/AB stain.


Asunto(s)
Pólipos del Colon/patología , Pólipos Adenomatosos/patología , Adulto , Anciano , Transformación Celular Neoplásica/patología , Neoplasias del Colon/patología , Femenino , Humanos , Hiperplasia , Mucosa Intestinal/patología , Masculino , Persona de Mediana Edad , Mucinas/metabolismo , Factores de Riesgo , Sialomucinas
18.
Gut ; 32(2): 137-40, 1991 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-1864530

RESUMEN

An intensive histological search for Helicobacter pylori in gastric biopsy specimens has led to the detection of other spiral shaped bacteria in the human gastric mucosa. The clinical and morphological findings of 39 cases (0.25% of all gastric biopsies performed in the observation period) are reported for 34 patients (87.2%) complaining of upper abdominal discomfort. Five patients (12.8%) had chronic gastritis and 34 (87.2%) chronic active gastritis. The organisms were seen by light microscopy deep in the gastric foveolae and intracellularly. The scanning and transmission electron microscopic findings show bacteria which invade and damage gastric mucosal cells. These organisms are similar to the spiral shaped bacteria found in the stomachs of cats and dogs and non-human primates. In eight patients organisms were not detected after four weeks of treatment with bismuth salts. The disappearance of the organisms coincided with resolution of the chronic active gastritis and the symptoms.


Asunto(s)
Gastritis/microbiología , Bacterias Gramnegativas/ultraestructura , Adulto , Anciano , Femenino , Helicobacter pylori/ultraestructura , Humanos , Masculino , Microscopía Electrónica , Microscopía Electrónica de Rastreo , Persona de Mediana Edad , Antro Pilórico/microbiología , Estudios Retrospectivos
20.
Leber Magen Darm ; 20(4): 180, 183-6, 1990 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-2398773

RESUMEN

The endemic behaviour of Helicobacter pylori (H.p., formerly known as Campylobacter pylori) among the population of the town (57,000 inhabitants) and rural district (116,000 inhabitants) of Landshut was investigated with consideration being given to nationality, socio-economic status, housing and the local supply of drinking water. The study involved 894 patients, whose consecutive gastric biopsies were sent to the pathological institute of the Municipal Hospital in Landshut. The overall H.p. incidence was 51.1%, the average age of those infected being 56.9 years. No difference was found in the rate of infection between the municipal and rural populations (54.5%, average age 57.4 years/48.3%, average age 56.4 years). The population of foreigners revealed a significantly higher H.p.-positive rate (72.3%, average age 41.7 years) as compared with the native population (49.9%, average age 57.7 years). In the case of parts of the town whose inhabitants generally lived in smaller apartments with a lower standard of hygiene a considerable greater incidence of H.p. (up to 73.6%, average age 54.2 years) was observed as compared with areas with a low population density and detached houses (38.5%, average age 59.2 years). Considerable differences in rates of infection were established in the individual small towns and marketplaces of the rural district (between 40 and 71.4%, average age 58.6-59.1 years). No correlation was found to the supply of drinking water. Overall, the results of this study indicate a person-to-person transmission of H.p., possibly favoured by more frequent physical contact under more cramped living conditions in socio-economically disadvantaged strata of the population and by ethnological factors.


Asunto(s)
Infecciones por Campylobacter/epidemiología , Gastritis/epidemiología , Población Rural , Población Urbana , Adulto , Anciano , Anciano de 80 o más Años , Infecciones por Campylobacter/transmisión , Estudios Transversales , Femenino , Gastritis/microbiología , Alemania Occidental/epidemiología , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Factores de Riesgo , Factores Socioeconómicos
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