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2.
J Clin Microbiol ; 62(2): e0114023, 2024 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-38265207

RESUMEN

Candida glabrata is one of the most common causes of systemic candidiasis, often resistant to antifungal medications. To describe the genomic context of emerging resistance, we conducted a retrospective analysis of 82 serially collected isolates from 33 patients from population-based candidemia surveillance in the United States. We used whole-genome sequencing to determine the genetic relationships between isolates obtained from the same patient. Phylogenetic analysis demonstrated that isolates from 29 patients were clustered by patient. The median SNPs between isolates from the same patient was 30 (range: 7-96 SNPs), while unrelated strains infected four patients. Twenty-one isolates were resistant to echinocandins, and 24 were resistant to fluconazole. All echinocandin-resistant isolates carried a mutation either in the FKS1 or FKS2 HS1 region. Of the 24 fluconazole-resistant isolates, 17 (71%) had non-synonymous polymorphisms in the PDR1 gene, which were absent in susceptible isolates. In 11 patients, a genetically related resistant isolate was collected after recovering susceptible isolates, indicating in vivo acquisition of resistance. These findings allowed us to estimate the intra-host diversity of C. glabrata and propose an upper boundary of 96 SNPs for defining genetically related isolates, which can be used to assess donor-to-host transmission, nosocomial transmission, or acquired resistance. IMPORTANCE In our study, mutations associated to azole resistance and echinocandin resistance were detected in Candida glabrata isolates using a whole-genome sequence. C. glabrata is the second most common cause of candidemia in the United States, which rapidly acquires resistance to antifungals, in vitro and in vivo.


Asunto(s)
Candidemia , Equinocandinas , Humanos , Equinocandinas/farmacología , Equinocandinas/uso terapéutico , Fluconazol/farmacología , Fluconazol/uso terapéutico , Candida glabrata , Candidemia/microbiología , Estudios Retrospectivos , Filogenia , Pruebas de Sensibilidad Microbiana , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Mutación , Genómica , Farmacorresistencia Fúngica/genética
3.
Epidemiol Infect ; 146(4): 508-514, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29429421

RESUMEN

To understand increasing rates of hepatitis C virus (HCV) infection in Tennessee, we conducted testing, risk factor analysis and a nested case-control study among persons who use drugs. During June-October 2016, HCV testing with risk factor assessment was conducted in sexually transmitted disease clinics, family planning clinics and an addiction treatment facility in eastern Tennessee; data were analysed by using multivariable logistic regression. A nested case-control study was conducted to assess drug-using risks and behaviours among persons who reported intranasal or injection drug use (IDU). Of 4753 persons tested, 397 (8.4%) were HCV-antibody positive. HCV infection was significantly associated with a history of both intranasal and IDU (adjusted odds ratio (aOR) 35.4, 95% confidence interval (CI) 24.1-51.9), IDU alone (aOR 52.7, CI 25.3-109.9), intranasal drug use alone (aOR 2.6, CI 1.8-3.9) and incarceration (aOR 2.7, CI 2.0-3.8). By 4 October 2016, 574 persons with a reported history of drug use; 63 (11%) were interviewed further. Of 31 persons who used both intranasal and injection drugs, 26 (84%) reported previous intranasal drug use, occurring 1-18 years (median 5.5 years) before their first IDU. Our findings provide evidence that reported IDU, intranasal drug use and incarceration are independent indicators of risk for past or present HCV infection in the study population.


Asunto(s)
Hepatitis C/epidemiología , Enfermedades de Transmisión Sexual/epidemiología , Adolescente , Adulto , Anciano , Estudios de Casos y Controles , Demografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Factores de Riesgo , Tennessee/epidemiología
4.
Infection ; 42(1): 165-70, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24243481

RESUMEN

We examined heavy alcohol use as a risk factor for severe influenza (intensive care admission or death) among hospitalized adults. In <65- and ≥65-year-olds, heavy alcohol use increased disease severity [relative risk (RR) 1.34; 95 % confidence interval (CI): 1.04-1.74, and RR 2.47; 95 % CI: 1.69-3.60, respectively]. Influenza vaccination and early, empiric antiviral treatment should be emphasized in this population.


Asunto(s)
Alcoholismo/complicaciones , Gripe Humana/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Hospitalización , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Adulto Joven
6.
J Clin Microbiol ; 49(4): 1583-7, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21325555

RESUMEN

We describe clinical and laboratory characteristics of invasive methicillin-resistant Staphylococcus aureus (MRSA) infections with vancomycin MICs of 2 µg/ml and compare heteroresistant-intermediate S. aureus (hVISA) to non-hVISA. Health care-associated community-onset infections were the most common and resulted in frequent complications and relapses. hVISA-infected patients were more likely to have been hospitalized in the year prior to MRSA culture.


Asunto(s)
Antibacterianos/farmacología , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Infecciones Estafilocócicas/microbiología , Infecciones Estafilocócicas/patología , Resistencia a la Vancomicina , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antibacterianos/uso terapéutico , Niño , Preescolar , Infecciones Comunitarias Adquiridas/microbiología , Infecciones Comunitarias Adquiridas/patología , Femenino , Hospitalización/estadística & datos numéricos , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Recurrencia , Resultado del Tratamiento , Adulto Joven
7.
Epidemiol Infect ; 135(6): 951-8, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17156502

RESUMEN

During the 2004-2005 influenza season two independent influenza surveillance systems operated simultaneously in three United States counties. The New Vaccine Surveillance Network (NVSN) prospectively enrolled children hospitalized for respiratory symptoms/fever and tested them using culture and RT-PCR. The Emerging Infections Program (EIP) and a similar clinical-laboratory surveillance system identified hospitalized children who had positive influenza tests obtained as part of their usual medical care. Using data from these systems, we applied capture-recapture analyses to estimate the burden of influenza related-hospitalizations in children aged<5 years. During the 2004-2005 influenza season the influenza-related hospitalization rate estimated by capture-recapture analysis was 8.6/10,000 children aged<5 years. When compared to this estimate, the sensitivity of the prospective surveillance system was 69% and the sensitivity of the clinical-laboratory based system was 39%. In the face of limited resources and an increasing need for influenza surveillance, capture-recapture analysis provides better estimates than either system alone.


Asunto(s)
Gripe Humana/epidemiología , Vigilancia de la Población/métodos , Preescolar , Hospitalización/estadística & datos numéricos , Humanos , Lactante , Recién Nacido , Estados Unidos/epidemiología
8.
Pediatrics ; 117(2): e157-63, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16452325

RESUMEN

OBJECTIVE: We sought to evaluate the impact of intense influenza media coverage during the 2003-2004 influenza season on the influenza vaccination status of children 6 to 59 months of age. METHODS: Children 6 to 59 months of age who presented to a large, academic pediatric continuity clinic or affiliated acute care clinic in the summer of 2004 were enrolled. A parental survey ascertained the influenza vaccination status of the child and family members during the 2003-2004 influenza season and factors that influenced their vaccination status. For children vaccinated in the clinic or health department, influenza vaccination dates were confirmed in a computerized medical chart or state immunization registry. RESULTS: Of 256 enrolled children, 98 (38%) parents reported that their child had received the 2003-2004 influenza vaccine, and 64 (65%) had confirmed influenza vaccination dates. Unlike the previous influenza season in which confirmed influenza vaccination dates from a similar study population were distributed more evenly from October through December, most children (75%) with confirmed vaccination dates received the vaccine after the media coverage in mid-November. Influenza vaccinations per week increased dramatically after the media coverage began (2.4 vs 8.6 per week; t test: P < .001). In late November and December 2003, the influenza-related media coverage, which focused primarily on an early, severe influenza season, increased dramatically and explained 85% of the variation in influenza vaccinations. Multivariate analysis showed that recalling a physician recommendation (odds ratio [OR]: 6.8; 95% confidence interval [CI]: 2.3-19.7), having a family member who had received the influenza vaccine (OR: 9.5; 95% CI: 4.3-21.3), having a continuity clinic visit between October and January (OR: 4.5; 95% CI: 2.0-10.1), and having a high-risk medical condition (OR: 2.9; 95% CI: 1.1-7.8) strongly predicted the influenza vaccination status in the children. CONCLUSION: Media coverage in conjunction with explicit physician recommendation for children and their contacts are key factors that are associated with influenza vaccination rates in children.


Asunto(s)
Gripe Humana/prevención & control , Medios de Comunicación de Masas , Vacunación/estadística & datos numéricos , Preescolar , Humanos , Lactante
9.
Planta Med ; 71(10): 910-6, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16254821

RESUMEN

Extracts of Vitex agnus-castus fruits (VACF) are described to have beneficial effects on disorders related to hyperprolactinemia (cycle disorders, premenstrual syndrome). A VACF extract has recently been shown to exhibit antitumor activities in different human cancer cell lines. In the present study, we explored the antiproliferative effects of a VACF extract with a particular focus on apoptosis-inducing and potential cytotoxic effects. Three different human prostate epithelial cell lines (BPH-1, LNCaP, PC-3) representing different disease stages and androgen responsiveness were chosen. The action of VACF on cell viability was assessed using the WST-8-tetrazolium assay. Cell proliferation in cells receiving VACF alone or in combination with a pan-caspase inhibitor (Z-VAD-fmk) was quantified using a Crystal Violet assay. Flow cytometric cell cycle analysis and measurement of DNA fragmentation using an ELISA method were used for studying the induction of apoptosis. Lactate dehydrogenase (LDH) activity was determined as a marker of cytotoxicity. The extract inhibited proliferation of all three cell lines in a concentration-dependent manner with IC (50) values below 10 microg/mL after treatment for 48 h. Cell cycle analysis and DNA fragmentation assays suggest that part of the cells were undergoing apoptosis. The VACF-induced decrease in cell number was partially inhibited by Z-VAD-fmk, indicating a caspase-dependent apoptotic cell death. However, the concentration-dependent LDH activity of VACF treated cells indicated cytotoxic effects as well. These data suggest that VACF contains components that inhibit proliferation and induce apoptosis in human prostate epithelial cell lines. The extract may be useful for the prevention and/or treatment not only of benign prostatic hyperplasia but also of human prostate cancer.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Apoptosis/efectos de los fármacos , Fitoterapia , Extractos Vegetales/farmacología , Vitex , Antineoplásicos Fitogénicos/administración & dosificación , Antineoplásicos Fitogénicos/uso terapéutico , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Células Epiteliales/efectos de los fármacos , Citometría de Flujo , Frutas , Humanos , Masculino , Extractos Vegetales/administración & dosificación , Extractos Vegetales/uso terapéutico , Próstata/citología , Hiperplasia Prostática/tratamiento farmacológico
10.
Med Mycol ; 43(3): 219-25, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-16010848

RESUMEN

This is a cohort study of pediatric outpatients receiving total parenteral nutrition (TPN) and follow-up care in a Tennessee hospital between January and June 1999. The study was conducted following an increase in the incidence of candidemia. Of 13 children receiving home TPN, five had candidemia; three were due to Candida parapsilosis. Case patients were more likely to have an underlying hematologic disease (P = 0.02) as well as previous history of fungemia (P = 0.02). Two case patients had successive candidemia episodes 3 months apart; karyotypes and RAPD profiles of each patient's successive C. parapsilosis isolates were similar. Candida spp. were frequently detected in hand cultures from cohort members (four of 10) and family member caregivers (nine of 11); C parapsilosis was isolated from five caregivers. Our findings underscore the challenges of maintaining stringent infection control practices in the home health care setting and suggest the need for more intensive follow-up and coordination of home TPN therapy among pediatric patients.


Asunto(s)
Atención Ambulatoria , Candidiasis/etiología , Infección Hospitalaria/etiología , Fungemia/etiología , Nutrición Parenteral Total/efectos adversos , Adolescente , Candida/aislamiento & purificación , Candidiasis/epidemiología , Cuidadores , Niño , Estudios de Cohortes , Infección Hospitalaria/epidemiología , Femenino , Fungemia/epidemiología , Mano/microbiología , Hospitales Pediátricos , Humanos , Incidencia , Lactante , Masculino , Factores de Riesgo , Especificidad de la Especie , Tennessee/epidemiología
11.
Maturitas ; 51(4): 397-404, 2005 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-16039414

RESUMEN

OBJECTIVES: To compare the efficacy and safety of the black cohosh root extract Cr 99 with placebo in women with climacteric complaints. METHODS: A multicenter, randomized, placebo-controlled, double-blind, parallel group study was conducted in 122 menopausal women (intention-to-treat population) with > or =3 hot flashes a day, treated over 12 weeks. Two main efficacy measures - weekly weighted score of hot flashes and Kupperman Index - and secondary efficacy variables, e.g. Menopause Rating Scale, were defined. Routine safety laboratory parameters and adverse events were documented. RESULTS: The primary efficacy analysis showed no superiority of the tested black cohosh extract compared to placebo. However, in the subgroup of patients with a Kupperman Index> or =20 a significant superiority regarding this index could be demonstrated (P<0.018). A decrease of 47% and 21% was observed in the black cohosh and placebo group, respectively. The weekly weighted scores of hot flashes (P<0.052) and the Menopause Rating Scale (P<0.009) showed similar results. Prevalence and intensity of the adverse events did not differ in the two treatment groups. CONCLUSIONS: The results indicate a superiority of the tested Cimicifuga racemosa extract compared to placebo in patients with menopausal disorders of at least moderate intensity according to a Kupperman Index > or =20, but not in the intention-to-treat population as a whole.


Asunto(s)
Cimicifuga , Sofocos/tratamiento farmacológico , Menopausia/efectos de los fármacos , Fitoterapia , Extractos Vegetales/uso terapéutico , Método Doble Ciego , Femenino , Humanos , Persona de Mediana Edad , Placebos , Extractos Vegetales/administración & dosificación , Resultado del Tratamiento
12.
Gene Ther ; 10(7): 530-9, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12646858

RESUMEN

To generate a replication-competent adenovirus (Ad) with specificity for melanoma, we constructed a tissue-specific promoter restricting E1A expression to melanoma cells. The combination of four copies of a mouse tyrosinase enhancer element (TE) fused to the human tyrosinase promoter (TP) yielded up to 2000-fold higher luciferase reporter activity in tyrosinase-expressing melanoma cells than in nonmelanoma cells. Insertion of the composite TETP construct upstream of the E1A gene was combined with deleting as far as possible the intertwined endogenous Ad enhancer/promoter (EP). The resulting AdDeltaEP-TETP vector, also deleted for the E3 region, was found to replicate in tyrosinase-positive melanoma cells, such as SK-Mel23 as efficiently as wild-type Ad5, but at a more than 50-fold reduced level in nonmelanoma tumour cells and primary human cells. Injection of AdDeltaEP-TETP into xenotransplanted melanomas, but not into HeLa-derived tumours led to long-lasting tumour regression in nude mice. This AdDeltaEP-TETP virus might be useful for the treatment of accessible lesions in advanced melanoma patients.


Asunto(s)
Adenoviridae/genética , Terapia Genética/métodos , Vectores Genéticos/administración & dosificación , Melanoma/terapia , Neoplasias Experimentales/terapia , Transducción Genética/métodos , Proteínas E1A de Adenovirus/genética , Animales , Expresión Génica , Ingeniería Genética , Células HeLa , Humanos , Melanoma/enzimología , Ratones , Ratones Desnudos , Monofenol Monooxigenasa/genética , Neoplasias Experimentales/enzimología , Proteínas Recombinantes de Fusión/genética , Secuencias Reguladoras de Ácidos Nucleicos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Células Tumorales Cultivadas , Replicación Viral
13.
Planta Med ; 68(9): 804-7, 2002 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12357391

RESUMEN

The biflavone amentoflavone is an ingredient of Hypericum perforatum L. (Clusiaceae), a plant which is widely used for the treatment of mild to moderate depression. Amentoflavone inhibits the binding of flumazenil to the benzodiazepine binding site of the GABA A -receptor (IC(50) = 14.9 nM). Since it has to pass the blood-brain barrier (BBB) before reaching this receptor, the penetration of [(3)H]-amentoflavone through BBB was studied in an in vitro model consisting of primary cell cultures of porcine brain capillary endothelial cells (BCEC). Concentration-dependent uptake (37-2000 nM) was neither saturable nor temperature-sensitive indicating passive diffusion as the major uptake mechanism. This finding was confirmed by transport experiments through BCEC monolayers (> 2 % of applied dose was transported after 30 min). Co-administration of Hypericum extract increased amentoflavone transport significantly (amentoflavone alone: permeability coefficient P(app) = 4.59.10(-6) cm/s; co-administrated sucrose: P(app) = 3.22.10(-6)cm/s; amentoflavone together with hypericum: P(app) = 6.74.10(-6)cm/s, co-administrated sucrose P(app) = 5.49.10(-6)cm/s) indicating that Hypericum constituents enhance amentoflavone transport possibly by modulating paracellular permeability. Experiments with the P-glycoprotein (P-gp) overexpressing cell line P388-MDR showed that amentoflavone uptake was significantly enhanced by addition of the P-gp inhibitor verapamil, suggesting a P-gp mediated back-transport out of the cells. In conclusion, our findings show, that amentoflavone is able to pass the blood-brain barrier in vitro by passive diffusion.


Asunto(s)
Biflavonoides , Barrera Hematoencefálica/efectos de los fármacos , Flavonoides/farmacología , Hypericum , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Animales , Transporte Biológico/efectos de los fármacos , Células Cultivadas , Relación Dosis-Respuesta a Droga , Endotelio Vascular/efectos de los fármacos , Extractos Vegetales/farmacología , Porcinos , Tritio/metabolismo , Células Tumorales Cultivadas , Verapamilo/farmacología
14.
Bioessays ; 23(11): 1010-7, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11746217

RESUMEN

It has been suggested that metallothioneins, discovered about 45 years ago, play a central role in heavy metal metabolism and detoxification, and in the management of various forms of stress. The metal-regulatory transcription factor-1 (MTF-1) was shown to be essential for basal and heavy metal-induced transcription of the stress-responsive metallothionein-I and metallothionein-II. Recently it has become obvious that MTF-1 has further roles in the transcriptional regulation of genes induced by various stressors and might even contribute to some aspects of malignant cell growth. Furthermore, MTF-1 is an essential gene, as mice null-mutant for MTF-1 die in utero due to liver degeneration. We describe here the state of knowledge on the complex activation of MTF-1, and propose a model with MTF-1 as an interconnected cellular stress-sensor protein involved in heavy metal metabolism, hepatocyte differentiation and detoxification of toxic agents.


Asunto(s)
Transactivadores/metabolismo , Factores de Transcripción/metabolismo , Animales , Proteínas de Unión al ADN , Humanos , Metales Pesados/metabolismo , Ratones , Ratones Noqueados , Regiones Promotoras Genéticas , Transactivadores/genética , Transactivadores/fisiología , Factores de Transcripción/genética , Factores de Transcripción/fisiología , Factor de Transcripción MTF-1
16.
Am J Epidemiol ; 154(11): 1000-5, 2001 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-11724715

RESUMEN

To monitor disease incidence and antibiotic resistance, effective, practical surveillance strategies are needed at the local level for drug-resistant Streptococcus pneumoniae (DRSP). Knox County, Tennessee, participates in three forms of DRSP surveillance: an active system sponsored by the Centers for Disease Control and Prevention (CDC; Atlanta, Georgia); a novel county-sponsored system; and conventional state-mandated reporting. Ascertainment of invasive S. pneumoniae infection cases by each system in 1998 was evaluated, and completeness of reporting, antibiotic resistance patterns, costs, and other attributes were compared. The county-sponsored system collects patient identifiers and drug susceptibility data directly from hospital laboratories, whereas the CDC-sponsored system performs medical chart abstractions and reference laboratory susceptibility testing. Similar numbers of invasive S. pneumoniae cases were detected by the county-sponsored (n = 127) and CDC-sponsored (n = 123) systems; these systems held >75% of all cases in common, and each system achieved >85% sensitivity. Conventional reporting contained 88% and 76% of the DRSP cases identified by the county- and CDC-sponsored systems, respectively, but did not capture infections produced by susceptible isolates. Both the county- and CDC-sponsored systems indicated that large proportions of isolates were resistant to penicillin and extended-spectrum cephalosporins. The county-sponsored DRSP surveillance system was inexpensive, simple to execute, and relevant to local needs.


Asunto(s)
Infecciones Comunitarias Adquiridas/microbiología , Infecciones Neumocócicas/epidemiología , Vigilancia de la Población/métodos , Streptococcus pneumoniae/efectos de los fármacos , Streptococcus pneumoniae/aislamiento & purificación , Infecciones Comunitarias Adquiridas/epidemiología , Farmacorresistencia Microbiana , Humanos , Laboratorios de Hospital , Pruebas de Sensibilidad Microbiana/economía , Pruebas de Sensibilidad Microbiana/métodos , Infecciones Neumocócicas/microbiología , Tennessee/epidemiología
17.
JAMA ; 286(15): 1857-62, 2001 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-11597287

RESUMEN

CONTEXT: Macrolide antibiotics, including erythromycin, clarithromycin, and azithromycin, are the mainstays of empirical pneumonia therapy. Macrolide resistance among Streptococcus pneumoniae, the most common cause of community-acquired pneumonia, is increasing in the United States. Whether resistance is a significant problem or whether macrolides remain useful for treatment of most resistant strains is unknown. OBJECTIVE: To examine the epidemiology of macrolide-resistant pneumococci in the United States. DESIGN AND SETTING: Analysis of 15 481 invasive isolates from 1995 to 1999 collected by the Centers for Disease Control and Prevention's Active Bacterial Core surveillance system in 8 states. MAIN OUTCOME MEASURES: Trends in macrolide use (1993-1999) and resistance and factors associated with resistance, including examination of 2 subtypes, the M phenotype, associated with moderate minimum inhibitory concentrations (MICs), and the MLS(B) phenotype, associated with high MICs and clindamycin resistance. RESULTS: From 1993 to 1999, macrolide use increased 13%; macrolide use increased 320% among children younger than 5 years. Macrolide resistance increased from 10.6% in 1995 to 20.4% in 1999. M phenotype isolates increased from 7.4% to 16.5% (P<.001), while the proportion with the MLS(B) phenotype was stable (3%-4%). The median erythromycin MIC (MIC(50)) of M phenotype isolates increased from 4 microg/mL to 8 microg/mL. In 1999, M phenotype strains were more often from children than persons 5 years or older (25.2% vs 12.6%; P<.001) and from whites than blacks (19.3% vs 11.2%; P<.001). CONCLUSIONS: In the setting of increasing macrolide use, pneumococcal resistance has become common. Most resistant strains have MICs in the range in which treatment failures have been reported. Further study and surveillance are critical to understanding the clinical implications of our findings.


Asunto(s)
Antibacterianos/farmacología , Infecciones Neumocócicas/tratamiento farmacológico , Streptococcus pneumoniae/efectos de los fármacos , Adolescente , Adulto , Antibacterianos/uso terapéutico , Niño , Preescolar , Farmacorresistencia Microbiana , Utilización de Medicamentos/estadística & datos numéricos , Humanos , Lactante , Modelos Logísticos , Macrólidos , Pruebas de Sensibilidad Microbiana , Análisis Multivariante , Fenotipo , Infecciones Neumocócicas/epidemiología , Serotipificación , Streptococcus pneumoniae/clasificación , Estados Unidos/epidemiología
18.
Pharmacopsychiatry ; 34 Suppl 1: S137-42, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11518063

RESUMEN

The effect of extracts and constituents of St. John's wort, Hypericum perforatum, at various CNS receptors were studied by radioligand binding techniques in order to determine a profile of pharmacological activity in vitro. Binding inhibition was examined for the G-protein coupled opioid, serotonin (5-HT), histamine, neurokinin and corticotropin releasing factor (CRF) receptors, for the steroid estrogen-alpha receptor and for the ligand-gated ionchannel GABA(A) receptor. Hypericin showed the most potent binding inhibiton of all tested constituents to human CRF1 receptor with an IC50 value of 300 nM. Preliminary GTPgamma35S binding studies to CRF1 coupled G-protein indicated an antagonistic action for hypericin. The acylphloroglucinole hyperforin failed to inhibit 125I-astressin binding to hCRF, receptor up to 10 microM. Hyperforin inhibited binding to opioid and serotonin (5-HT) receptors at IC50 values between 0.4 and 3 microM, while hypericin and pseudohypericin inhibited with weaker potency. The biflavonoid I3,II8-biapigenin inhibited 3H-estradiol binding to the estrogen-alpha receptor with an IC50 value of 1 microM. The inhibition of 3H-muscimol binding to the GABA(A) receptor is likely to be exclusively due to GABA present in the extract. We therefore hypothesize that additive or synergistic actions of several ditsinct compounds may be responsible for the beneficial antidepressant effect of St. John's wort.


Asunto(s)
Cerebelo/química , Cerebelo/efectos de los fármacos , Hypericum , Extractos Vegetales/farmacología , Animales , Cerebelo/metabolismo , Femenino , Proteínas de Unión al GTP/metabolismo , Técnicas In Vitro , Masculino , Ensayo de Unión Radioligante , Ratas , Ratas Wistar , Receptores de Hormona Liberadora de Corticotropina/metabolismo , Receptores de Estrógenos/metabolismo , Receptores de GABA-A/metabolismo , Receptores Histamínicos/metabolismo , Receptores de Glutamato Metabotrópico/metabolismo , Receptores de Neuroquinina-1/metabolismo , Receptores de Serotonina/metabolismo
19.
Clin Infect Dis ; 33(5): 662-75, 2001 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-11486289

RESUMEN

Streptococcus pneumoniae remains a major cause of disease worldwide; the emergence of antibiotic-resistant strains emphasizes the importance of disease prevention by use of vaccines. Recent studies have provided information that is useful for the evaluation of current vaccine recommendations. Recommendations target most people who are at high risk for invasive pneumococcal disease. However, higher risk has also been identified for African Americans and smokers, but these groups are not specifically targeted by current recommendations. The vaccine is effective against invasive disease in immunocompetent people, although studies in immunocompromised subjects have found few subgroups in which the vaccine appears to be effective. Questions with regard to optimal timing and indications for revaccination remain a challenge, because the duration of protection and effectiveness of revaccination remain unknown. New pneumococcal vaccines appear promising but will need to be tested against the performance of the polysaccharide vaccine. Improving delivery of the currently available pneumococcal polysaccharide vaccine to adults who will benefit should be a high priority.


Asunto(s)
Infecciones Neumocócicas/epidemiología , Infecciones Neumocócicas/prevención & control , Vacunas Neumococicas/uso terapéutico , Adolescente , Adulto , Anciano , Enfermedad Crónica , Humanos , Programas de Inmunización , Incidencia , Persona de Mediana Edad , Infecciones Neumocócicas/etiología , Vacunas Neumococicas/administración & dosificación , Vacunas Neumococicas/farmacología , Polisacáridos , Guías de Práctica Clínica como Asunto/normas , Ensayos Clínicos Controlados Aleatorios como Asunto , Factores de Riesgo , Resultado del Tratamiento , Estados Unidos/epidemiología
20.
Am J Respir Crit Care Med ; 164(1): 77-81, 2001 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-11435242

RESUMEN

Jails are an important reservoir of tuberculosis infection in the United States. Screening for active disease in these high-risk settings is difficult. We used decision analysis to assess the cost effectiveness of routine miniature chest radiography for screening for tuberculosis on admission to jail. Infection rates, probabilities, and costs associated with detecting and treating tuberculosis were derived from published studies. We calculated an average total cost of $6.60 per inmate for routine radiograph screening on admission to jail. The cost of screening for active tuberculosis with miniature chest radiography was estimated to be $9,600 per case identified, compared with $32,100 per case with tuberculin skin testing and $54,100 per case with symptom screening. Chest radiography would also identify substantially more cases than other methods of screening. Screening for tuberculosis with miniature chest radiography is cost effective even under a wide range of assumptions regarding risk factors and prevalence of disease. Miniature chest radiography should be strongly considered as an important tool in the fight to eliminate tuberculosis from the high-risk populations that may be reached through screening in jails.


Asunto(s)
Análisis Costo-Beneficio , Tamizaje Masivo/economía , Prisiones , Prueba de Tuberculina/economía , Tuberculosis/diagnóstico , Técnicas de Apoyo para la Decisión , Humanos , Incidencia , Radiografía , Sensibilidad y Especificidad , Tuberculosis/diagnóstico por imagen , Tuberculosis/economía , Tuberculosis/epidemiología , Estados Unidos/epidemiología
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