Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 188
Filtrar
Más filtros

Banco de datos
Tipo del documento
Intervalo de año de publicación
1.
Epidemiol Infect ; 144(15): 3316-3325, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27488877

RESUMEN

This study was conducted to examine the incidence trend of campylobacteriosis in Michigan over a 10-year period and to investigate risk factors and clinical outcomes associated with infection. Campylobacter case data from 2004 to 2013 was obtained from the Michigan Disease Surveillance System. We conducted statistical and spatial analyses to examine trends and identify factors linked to campylobacteriosis as well as ecological associations using animal density data from the National Agricultural Statistics Service. An increasing trend of Campylobacter incidence and hospitalization was observed, which was linked to specific age groups and rural residence. Cases reporting ruminant contact and well water as the primary drinking source had a higher risk of campylobacteriosis, while higher cattle density was associated with an increased risk at the county level. Additional studies are needed to identify age-specific risk factors and examine prevalence and transmission dynamics in ruminants and the environment to aid in the development of more effective preventive strategies.


Asunto(s)
Infecciones por Campylobacter/epidemiología , Campylobacter/fisiología , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Infecciones por Campylobacter/microbiología , Niño , Preescolar , Femenino , Humanos , Incidencia , Lactante , Recién Nacido , Masculino , Michigan/epidemiología , Persona de Mediana Edad , Factores de Riesgo , Población Rural , Adulto Joven
2.
Epidemiol Infect ; 144(7): 1394-405, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-26584572

RESUMEN

Infection with Shiga toxin-producing Escherichia coli (STEC) by serotypes other than O157 (non-O157) have been increasingly reported in the United States. This increase in reporting is primarily due to the improvements in diagnostic tests. We analysed 1497 STEC cases reported in Michigan from 2001 to 2012. A significant increase in the number of non-O157 STEC cases was observed over time, and similar incidence rates were observed for O157 and non-O157 STEC cases in certain time periods. The odds of hospitalization was two times higher in O157 STEC cases relative to non-O157 STEC cases when adjusted for age and gender, suggesting that O157 STEC causes more severe clinical outcomes in all age groups. The use of population-based surveillance to better define trends and associations with disease severity are critical to enhance our understanding of STEC infections and improve upon current prevention and control efforts.


Asunto(s)
Infecciones por Escherichia coli/epidemiología , Síndrome Hemolítico-Urémico/epidemiología , Escherichia coli Shiga-Toxigénica/fisiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Infecciones por Escherichia coli/microbiología , Femenino , Síndrome Hemolítico-Urémico/microbiología , Humanos , Incidencia , Lactante , Recién Nacido , Masculino , Michigan/epidemiología , Persona de Mediana Edad , Adulto Joven
3.
Intern Med J ; 44(5): 512-4, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24816312

RESUMEN

The refeeding syndrome is increasingly recognised. It is a serious change in electrolytes when nutrition is reintroduced to malnourished patients. Alcohol dependence is a risk factor for the refeeding syndrome. We report a prospective cohort study of 36 alcoholics hospitalised for withdrawal management. We found no evidence of refeeding syndrome in any patient after 3 days of hospitalisation, despite hypomagnesaemia, a risk factor for the refeeding syndrome being prevalent (44% of subjects). Low thiamine levels were infrequent affecting 3/29 (10%). We recommend that in alcoholics admitted for managed withdrawal, risk of refeeding syndrome appears to be low, and routine testing of repeat electrolytes appears unnecessary.


Asunto(s)
Alcoholismo/rehabilitación , Unidades Hospitalarias , Síndrome de Realimentación/epidemiología , Adulto , Anciano , Alcoholismo/complicaciones , Análisis Químico de la Sangre/estadística & datos numéricos , Pruebas Diagnósticas de Rutina/estadística & datos numéricos , Dieta , Electrólitos/sangre , Femenino , Humanos , Masculino , Desnutrición/sangre , Desnutrición/dietoterapia , Desnutrición/etiología , Persona de Mediana Edad , Admisión del Paciente , Prevalencia , Estudios Prospectivos , Síndrome de Realimentación/sangre , Síndrome de Realimentación/etiología , Tiamina/sangre , Tiamina/uso terapéutico , Deficiencia de Tiamina/tratamiento farmacológico , Deficiencia de Tiamina/epidemiología , Deficiencia de Tiamina/etiología , Procedimientos Innecesarios , Victoria/epidemiología , Adulto Joven
4.
Nat Genet ; 27(4): 412-6, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11279523

RESUMEN

Fate-mapping experiments in the mouse have revealed that the primitive streak can be divided into three functional regions: the proximal region gives rise to germ cells and the extra-embryonic mesoderm of the yolk sac; the distal region generates cardiac mesoderm and node-derived axial mesendoderm; and the middle streak region produces the paraxial, intermediate and lateral plate mesoderm of the trunk. To gain insight into the mechanisms that mediate the assembly of the primitive streak into these functional regions, we have cloned and functionally identified the gene disrupted in the amnionless (amn) mouse, which has a recessive, embryonic lethal mutation that interferes specifically with the formation and/or specification of the middle primitive streak region during gastrulation. Here we report that the gene Amn encodes a novel type I transmembrane protein that is expressed exclusively in the extra-embryonic visceral endoderm layer during gastrulation. The extracellular region of the Amn protein contains a cysteine-rich domain with similarity to bone morphogenetic protein (BMP)-binding cysteine-rich domains in chordin, its Drosophila melanogaster homolog (Short gastrulation) and procollagen IIA (ref. 3). Our findings indicate that Amn may direct the production of trunk mesoderm derived from the middle streak by acting in the underlying visceral endoderm to modulate a BMP signaling pathway.


Asunto(s)
Cisteína/metabolismo , Endodermo/metabolismo , Gástrula/citología , Proteínas de la Membrana/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Cartilla de ADN , Inmunohistoquímica , Hibridación in Situ , Proteínas de la Membrana/química , Ratones , Datos de Secuencia Molecular , Homología de Secuencia de Aminoácido
5.
JDR Clin Trans Res ; 8(4): 394-401, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-35678084

RESUMEN

INTRODUCTION: Early childhood caries (ECC) is a complex oral disease that is prevalent in US children. OBJECTIVES: The purpose of this 2-y prospective cohort study was to examine baseline and time-dependent risk factors for ECC onset in initially caries-free preschool children. METHODS: A cohort of 189 initially caries-free children aged 1 to 3 y was recruited. At each 6-mo study visit, children were examined using the ICDAS index; salivary samples were collected to assess mutans streptococci (MS), lactobacilli, Candida species, salivary cortisol (prior and after a stressor), and salivary IgA. Diet and oral health behavior were assessed from parent report. Child and family stress exposure was assessed from measures of psychological symptoms, stressful life event exposure, family organization and violence exposure, and social support. Sociodemographic factors were also considered. A Kaplan-Meier estimator of survival function of time to ECC and a Cox proportional hazards model were used to identify predictors of ECC onset. RESULTS: Onset of ECC was associated with high salivary MS levels at baseline (log-rank test, P < 0.0001). Cox proportional hazards regression showed that the risk of dental caries significantly increased with salivary MS in log scale over the 6-mo period (hazard ratio, 1.08; P = 0.01). Other risk factors in the model did not reach statistical significance. CONCLUSION: Our results provide prospective evidence that an increase in salivary MS predicts ECC onset in young, initially caries-free children, confirming that a high salivary MS count likely plays a causal role in ECC onset, independent of covariates. KNOWLEDGE TRANSFER STATEMENT: These results suggest that we must focus on reducing salivary MS counts in young children and preventing or delaying MS colonization in infants and young children determined to be at risk for ECC.


Asunto(s)
Caries Dental , Lactante , Humanos , Preescolar , Estudios Prospectivos , Estudios Longitudinales , Caries Dental/epidemiología , Streptococcus mutans , Modelos de Riesgos Proporcionales
6.
Euro Surveill ; 15(3)2010 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-20122379

RESUMEN

This study aimed to measure rates of hand sanitiser use in a hospital entrance foyer four months after a baseline study during New Zealand s influenza pandemic. Of the 743 people observed over one (summer) day in December 2009, 8.2% used the hand sanitiser, which was significantly lower (p<0.0001) than the 18.0% reported in the August (winter) study. Health authorities may need to intensify promotion of hand hygiene to reduce the impact of future influenza pandemic waves.


Asunto(s)
Brotes de Enfermedades/prevención & control , Desinfección de las Manos , Subtipo H1N1 del Virus de la Influenza A , Gripe Humana/prevención & control , Adulto , Niño , Infección Hospitalaria/epidemiología , Infección Hospitalaria/prevención & control , Femenino , Estudios de Seguimiento , Humanos , Transmisión de Enfermedad Infecciosa de Profesional a Paciente/prevención & control , Subtipo H1N1 del Virus de la Influenza A/efectos de los fármacos , Gripe Humana/epidemiología , Masculino , Nueva Zelanda/epidemiología , Factores de Tiempo
7.
Science ; 294(5551): 2532-5, 2001 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-11743159

RESUMEN

We report an extensive program of high-precision radiocarbon dating to establish the best date for a floating 1599-year Anatolian tree ring chronology that spans the later third millennium B.C. through the earlier first millennium B.C. This chronology is directly associated with a number of key sites and ancient personages. A previously suggested dating is withdrawn and is replaced by a robust new date fix 22 (+4 or -7) years earlier. These new radiocarbon wiggle-matched dates offer a unique independent resource for establishing the precise chronology of the ancient Near East and Aegean and help resolve, among others, a long-standing debate in favor of the so-called Middle Mesopotamian chronology.


Asunto(s)
Arqueología , Radioisótopos de Carbono , Árboles , Atmósfera , Teorema de Bayes , Dióxido de Carbono , Alemania , Irlanda , Análisis de los Mínimos Cuadrados , Pinus/crecimiento & desarrollo , Quercus/crecimiento & desarrollo , Estaciones del Año , Programas Informáticos , Tiempo , Árboles/crecimiento & desarrollo , Turquía , Madera
8.
Science ; 294(5551): 2529-32, 2001 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-11743160

RESUMEN

Radiocarbon dating methods typically assume that there are no significant tropospheric (14)CO(2) gradients within the low- to mid-latitude zone of the Northern Hemisphere. Comparison of tree ring (14)C data from southern Germany and Anatolia supports this assumption in general but also documents episodes of significant short-term regional (14)CO(2) offsets. We suggest that the offset is caused by an enhanced seasonal (14)CO(2) cycle, with seasonally peaked flux of stratospheric (14)C into the troposphere during periods of low solar magnetic activity, coinciding with substantial atmospheric cooling. Short-term episodes of regional (14)CO(2) offsets are important to palaeoclimate studies and to high-resolution archaeological dating.


Asunto(s)
Arqueología , Atmósfera , Dióxido de Carbono , Radioisótopos de Carbono , Árboles , Calibración , Clima , Alemania , Región Mediterránea , Océanos y Mares , Estaciones del Año , Tiempo , Árboles/crecimiento & desarrollo , Turquía , Madera
9.
Mar Pollut Bull ; 1452019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31147084

RESUMEN

Shoreline discharge representing approximately 80% of sewage generated by Sydney (Australia) was replaced with three deepwater ocean outfalls between 1990 and 1991. Beachwatch bacterial monitoring data collected between 1989 and 2016 were analysed to assess the impact of commissioning on bathing water quality along 32 km of coastline. Bacterial contamination was reduced by 26-99% during the first 32 months post-commissioning and in the longer post-commissioning period, 1993 to 2016, bathing water quality improved for 31 beaches. Relatively stable bathing water quality was observed for five other beaches after the 2001 upgrade of another shoreline wastewater treatment plant. Bacterial contamination of bathing water in this 24-year post-commissioning period was most influenced by rainfall in the 24-h to 9 am on the day of sampling. Bacterial contamination from surfacing shore-blown wastewater plumes was not evident, whereas stormwater-delivered bacterial contamination was apparent and varied between beaches.


Asunto(s)
Agua de Mar/química , Aguas del Alcantarillado/análisis , Australia , Bacterias/genética , Bacterias/crecimiento & desarrollo , Bacterias/aislamiento & purificación , Playas , Ciudades , Monitoreo del Ambiente , Océanos y Mares , Agua de Mar/microbiología , Aguas del Alcantarillado/microbiología , Calidad del Agua
10.
Neuropathol Appl Neurobiol ; 34(4): 379-93, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18221261

RESUMEN

AIMS: Periventricular white matter injury in premature infants occurs following hypoxia/ischaemia and systemic infection, and results in hypomyelination, as well as neuromotor and cognitive deficits later in life. Inflammatory infiltrates are seen within human cerebral white matter from periventricular leucomalacia (PVL) cases. METHODS: In this study, we examine the time course of CD-68+ microglial cell responses relative to cell death within white matter following hypoxia/ischaemia in a rat model of PVL. We also tested the efficacy of the minocycline, an agent that suppresses microglial activation, in this model when administered as a post-insult treatment. RESULTS: We show that preoligodendrocyte injury in the post-natal day 6 begins within 24 h and continues for 48-96 h after hypoxia/ischaemia, and that microglial responses occur primarily over the first 96 h following hypoxia/ischaemia. Minocycline treatment over this 96 h time window following the insult resulted in significant protection against white matter injury, and this effect was concomitant with a reduction in CD-68+ microglial cell numbers. CONCLUSIONS: These results suggest that anti-inflammatory treatments may represent a useful strategy in the treatment of PVL, where clinical conditions would favour a post-insult treatment strategy.


Asunto(s)
Hipoxia-Isquemia Encefálica/prevención & control , Leucomalacia Periventricular/complicaciones , Leucomalacia Periventricular/fisiopatología , Microglía/patología , Minociclina/uso terapéutico , Tegmento Mesencefálico/lesiones , Animales , Animales Recién Nacidos , Muerte Celular , Modelos Animales de Enfermedad , Humanos , Hipoxia Encefálica/patología , Hipoxia-Isquemia Encefálica/etiología , Hipoxia-Isquemia Encefálica/patología , Recién Nacido , Leucomalacia Periventricular/patología , Microglía/efectos de los fármacos , Proteína Básica de Mielina/metabolismo , Ratas , Ratas Long-Evans , Tegmento Mesencefálico/patología
11.
Ann Epidemiol ; 17(11): 854-62, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17689259

RESUMEN

PURPOSE: Group B Streptococcus (GBS) is a common inhabitant of the bowel and vaginal flora, with known transmission routes including sexual contact and vertical transmission from mother to infant. Food-borne transmission is also possible, as GBS is a known fish and bovine pathogen. We conducted a prospective cohort study in order to identify risk factors for acquisition. METHODS: We identified risk factors for GBS acquisition among college women (n = 129) and men (n = 128) followed at 3-week intervals for 3 months. RESULTS: A doubling in sex acts significantly increased incidence of GBS capsular type V by 80% (95% confidence interval [CI]: 1.19, 2.58), and other non-Ia or -Ib types combined by 40% (95% CI: 1.00, 2.06; incidence of capsular type Ia (odds ratio [OR] = 1.2; 95% CI: 0.71, 1.88; p = 0.57) and Ib (OR = 1.5, 95% CI: 0.75, 2.86; p = 0.27) were elevated, although not significantly. After adjustment for sexual activity and sexual history, gender, and eating venue, fish consumption increased risk of acquiring capsular types Ia and Ib combined 7.3 fold (95% CI: 2.34, 19.50), but not of acquiring other capsular types. Beef and milk were not associated with GBS incidence. CONCLUSIONS: Different GBS capsular types may have different transmission routes.


Asunto(s)
Infecciones Estreptocócicas/transmisión , Streptococcus agalactiae/aislamiento & purificación , Adolescente , Adulto , Cápsulas Bacterianas , Dieta , Electroforesis en Gel de Campo Pulsado , Femenino , Desinfección de las Manos , Humanos , Incidencia , Masculino , Michigan/epidemiología , Polisacáridos Bacterianos/aislamiento & purificación , Estudios Prospectivos , Factores de Riesgo , Conducta Sexual , Infecciones Estreptocócicas/epidemiología , Streptococcus agalactiae/clasificación , Streptococcus agalactiae/patogenicidad , Estudiantes
12.
Mol Cell Biol ; 8(1): 10-6, 1988 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-3336353

RESUMEN

Several genes which are deactivated on the initiation of development of Dictyostelium discoideum were identified by differential screening of various cDNA libraries. These genes have in common a decrease in the steady-state levels of their corresponding mRNAs on the onset of development and as development proceeds. When development was carried out in the absence of protein synthesis by inhibition with cycloheximide, the decrease in mRNA levels for most genes (V genes) was normal or slightly accelerated. For about 5% of the genes (H genes), however, cycloheximide caused an apparent induction of expression, as revealed by a slight or dramatic increase in mRNA levels, instead of the normal decrease. This effect was due to inhibition of protein synthesis and not to cycloheximide per se. The induction was found to be due to an enhancement of the transcription rate; normal rates of transcription for the H genes were dependent on continued protein synthesis during vegetative growth and development. Thus, two general regulatory classes exist for deactivation of gene expression on initiation of development, one of which is dependent on and one of which is independent of protein synthesis. Analysis of expression of these genes in mutant strains which are aggregation deficient allowed the classes to be subdivided further. Taken together, these characterizations allow several distinct regulatory mechanisms to be identified that are involved in the deactivation of gene expression on the onset of development in D. discoideum.


Asunto(s)
Cicloheximida/farmacología , Dictyostelium/genética , Regulación de la Expresión Génica/efectos de los fármacos , Agregación Celular , Dictyostelium/crecimiento & desarrollo , Proteínas Fúngicas/biosíntesis , Proteínas Fúngicas/fisiología , Mutación , ARN de Hongos/genética , ARN Mensajero/genética , Factores de Tiempo , Transcripción Genética/efectos de los fármacos
13.
Clin Microbiol Infect ; 23(9): 673.e9-673.e16, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28274774

RESUMEN

OBJECTIVES: Because few studies have been conducted on group B Streptococcus (GBS) in Nigeria, we sought to estimate GBS colonization and transmission frequencies for 500 women and their newborns and identify risk factors for both outcomes. METHODS: GBS strains were characterized for antibiotic susceptibilities, capsule (cps) genotype, pilus island profile and multilocus sequence type (ST). RESULTS: In all, 171 (34.2%) mothers and 95 (19.0%) of their newborns were colonized with GBS; the vertical transmission rate was 48.5%. One newborn developed early-onset disease, yielding an incidence of 2.0 cases per 1000 live births (95% CI 0.50-7.30). Rectal maternal colonization (OR 26.6; 95% CI 13.69-51.58) and prolonged rupture of membranes (OR 4.2; 95% CI 1.03-17.17) were associated with neonatal colonization, whereas prolonged membrane rupture (OR 3.4; 95% CI 1.04-11.39) and young maternal age (OR 2.0; 95% CI 1.22-3.39) were associated with maternal colonization. Women reporting four or more intrapartum vaginal examinations (OR 6.1; 95% CI 3.41-10.93) and douching (OR 3.7; 95% CI 2.26-6.11) were also more likely to be colonized. Twelve STs were identified among 35 mother-baby pairs with evidence of transmission; strains of cpsV ST-19 (n = 9; 25.7%) and cpsIII ST-182 (n = 7; 20.0%) predominated. CONCLUSIONS: These data demonstrate high rates of colonization and transmission in a population that does not use antibiotics to prevent neonatal infections, a strategy that should be considered in the future.


Asunto(s)
Transmisión Vertical de Enfermedad Infecciosa/estadística & datos numéricos , Complicaciones Infecciosas del Embarazo/epidemiología , Infecciones Estreptocócicas/epidemiología , Streptococcus agalactiae , Adolescente , Adulto , Femenino , Humanos , Recién Nacido , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Estudios Longitudinales , Persona de Mediana Edad , Epidemiología Molecular , Nigeria/epidemiología , Embarazo , Complicaciones Infecciosas del Embarazo/prevención & control , Factores de Riesgo , Sepsis , Infecciones Estreptocócicas/prevención & control , Adulto Joven
14.
Cancer Res ; 61(2): 497-503, 2001 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-11212240

RESUMEN

15-Lipoxygenase (15-LOX)-2 is expressed in benign prostate secretory cells and benign prostate produces 15S-hydroxyeicosatetraenoic acid (15S-HETE) from exogenous arachidonic acid (AA). In contrast, 15S-LOX-2 and 15S-HETE formation are reduced in prostate carcinoma (Pca). The mechanisms whereby reduced 15-LOX-2 may contribute to Pca development or progression are not known. We investigated the expression of peroxisome proliferator-activated receptor (PPAR) gamma in benign and malignant prostate tissues and the ability of 15S-HETE to activate PPARgamma-dependent transcription and modulate proliferation of the Pca cell line PC3. In contrast to benign prostate and similar to most Pca tissues, 15-LOX-2 mRNA was not detected in PC3 cells, and they did not produce detectable 15-HETE from [14C]AA. By reverse transcription-PCR, PPARgamma mRNA was present in 18 of 18 benign and 9 of 9 tumor specimens. The PPARgamma ligand BRL 49653 and 15S-HETE caused a dose-dependent inhibition of PC3 proliferation in a 14-day soft agar colony-forming assay (IC50 of 3 and 30 microM, respectively). 15S-HETE (10 microM) caused greater inhibition than 10 microM 15R-HETE. At 3 days, BRL 49653 and 15S-HETE caused a slight increase in cells in G0-G1 and a corresponding decrease in cells in S phase. In PC3 cells transiently transfected with a luciferase reporter linked to a PPAR response element, 1 microM BRL 49653 and 10 microM 15S-HETE caused approximately threefold and greater than twofold induction of PPAR-dependent transcription, respectively. By quantitative real-time reverse transcription-PCR and Northern analysis, 3-day treatment with BRL 49653 and 15S-HETE caused a reduction of PPARgamma expression but a marked up-regulation of the PPAR response element containing adipocyte type fatty acid binding protein. These results support the hypothesis that 15-LOX-2-derived 15S-HETE may constitute an endogenous ligand for PPARgamma in the prostate and that loss of this pathway by reduced expression of 15-LOX-2 may contribute to increased proliferation and reduced differentiation in prostate carcinoma.


Asunto(s)
División Celular/efectos de los fármacos , Ácidos Hidroxieicosatetraenoicos/farmacología , Neoplasias de la Próstata/genética , Receptores Citoplasmáticos y Nucleares/genética , Tiazolidinedionas , Factores de Transcripción/genética , Agar/farmacología , Araquidonato 15-Lipooxigenasa/genética , Araquidonato 15-Lipooxigenasa/metabolismo , Northern Blotting , Catálisis , Medios de Cultivo/farmacología , Relación Dosis-Respuesta a Droga , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Ácidos Hidroxieicosatetraenoicos/metabolismo , Isoenzimas/genética , Isoenzimas/metabolismo , Luciferasas/efectos de los fármacos , Luciferasas/genética , Luciferasas/metabolismo , Masculino , Neoplasias de la Próstata/patología , ARN Mensajero/efectos de los fármacos , ARN Mensajero/genética , ARN Mensajero/metabolismo , Receptores Citoplasmáticos y Nucleares/metabolismo , Proteínas Recombinantes de Fusión/efectos de los fármacos , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Rosiglitazona , Tiazoles/farmacología , Factores de Transcripción/metabolismo , Transcripción Genética/efectos de los fármacos , Células Tumorales Cultivadas
15.
J Am Coll Cardiol ; 16(1): 200-6, 1990 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-2358594

RESUMEN

Currently there is no large animal model of dilated cardiomyopathy. The smaller animal models of cardiomyopathy, such as the Syrian hamster, cannot be studied with echocardiography and cardiac catheterization, and the relevance of these models to human dilated cardiomyopathy is open to question. On the basis of some initial observations in Doberman pinschers, it was speculated that these dogs could have occult left ventricular dysfunction. Accordingly, studies were performed in 46 apparently healthy Doberman pinschers and in 41 mongrel dogs: two-dimensional echocardiography (30 dogs in each group), cardiac catheterization (16 Doberman pinschers and 12 mongrels) and coronary blood flow studies (13 Doberman pinschers and 6 mongrels). In the awake, unsedated dogs studied with echocardiography, left ventricular wall thickening was significantly less in the Dobermans than in the mongrels (28% versus 36%, p = 0.0003). In the anesthetized dogs undergoing cardiac catheterization, left ventricular ejection fraction was significantly lower in the Dobermans than in the mongrels (0.38 versus 0.63, p = 0.0001). Rest coronary blood flow and coronary blood flow reserve were similar in the two groups. It is concluded that apparently healthy Doberman pinschers have occult left ventricular dysfunction. These dogs may serve as a large animal model of dilated cardiomyopathy and should not be used experimentally to study normal cardiac physiology.


Asunto(s)
Cardiomiopatía Dilatada/veterinaria , Modelos Animales de Enfermedad , Enfermedades de los Perros/fisiopatología , Animales , Cateterismo Cardíaco/veterinaria , Cardiomiopatía Dilatada/fisiopatología , Circulación Coronaria/fisiología , Perros , Ecocardiografía/veterinaria
16.
Mech Dev ; 57(2): 215-27, 1996 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8843398

RESUMEN

Reduction of wild-type activity of the polychaetoid (pyd) gene results in formation of extra mechanosensory bristles on the head and notum of adult Drosophila. Loss of pyd function results in decreased ability to restrict sensory organ precursor (SOP) formation to a single cell per proneural cluster. Although the initial proneural cluster pattern of achaete expression is not altered in pyd mutants, extra cells within proneural clusters express the high levels of achaete characteristic of SOPs. This observation suggests that pyd+ functions as a negative regulator of achaete-scute complex expression within the proneural cluster. Synergistic interactions between pyd and Notch, Delta and extramacrochaetae mutations support this model. We also demonstrate that pyd is required for normal eye development.


Asunto(s)
Drosophila/embriología , Regulación del Desarrollo de la Expresión Génica/fisiología , Genes de Insecto , Órganos de los Sentidos/embriología , Alelos , Animales , Embrión no Mamífero/embriología , Modelos Genéticos , Sistema Nervioso/embriología
17.
J Autism Dev Disord ; 35(4): 471-8, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16134032

RESUMEN

Recent evidence supports a role for genetics in autism, but other findings are difficult to reconcile with a purely genetic cause. Pathological changes in the cerebellum in autism are thought to correspond to an event before 30-32 weeks gestation. Our purpose was to determine whether there is an increased incidence of stressors in autism before this time period. Surveys regarding incidence and timing of prenatal stressors were distributed to specialized schools and clinics for autism and Down syndrome, and to mothers of children without neurodevelopmental diagnoses in walk-in clinics. Incidence of stressors during each 4-week block of pregnancy was recorded. Incidence of stressors in the blocks prior to and including the predicted time period (21-32 weeks gestation) in each group of surveys was compared to the other prenatal blocks. A higher incidence of prenatal stressors was found in autism at 21-32 weeks gestation, with a peak at 25-28 weeks. This does support the possibility of prenatal stressors as a potential contributor to autism, with the timing of stressors consistent with the embryological age suggested by neuroanatomical findings seen in the cerebellum in autism. Future prospective studies would be needed to confirm this finding.


Asunto(s)
Trastorno Autístico/epidemiología , Acontecimientos que Cambian la Vida , Estrés Psicológico/psicología , Trastorno Autístico/diagnóstico , Cerebelo/embriología , Niño , Síndrome de Down/epidemiología , Femenino , Enfermedades Fetales/epidemiología , Enfermedades Fetales/fisiopatología , Estudios de Seguimiento , Edad Gestacional , Humanos , Incidencia , Embarazo , Complicaciones del Embarazo/epidemiología , Prevalencia , Encuestas y Cuestionarios
18.
Int J Pediatr Otorhinolaryngol ; 69(2): 187-92, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15656951

RESUMEN

OBJECTIVES: The purpose of this study was to determine the best time to assess middle ear status with tympanometry for tympanometric instrument validation. The research question addressed three logical times for tympanometric reading prior to myringotomy. METHODS: Fifty-one children, ranging in age from nine months to 10 years, were recruited for this investigation. Participants underwent inhalant anesthesia for myringotomy and grommet placement with or without adenoidectomy and/or tonsillectomy. Tympanometry data was analyzed across three time periods. RESULTS: Findings indicated that tympanometric readings prior to anesthesia produced the most accurate results. CONCLUSIONS: Implicated in findings, in order to ensure that tympanometric instruments are reliable, typanometric measurements should be taken prior to the administration of any anesthesia.


Asunto(s)
Pruebas de Impedancia Acústica/métodos , Anestésicos por Inhalación/administración & dosificación , Halotano/administración & dosificación , Óxido Nitroso/administración & dosificación , Adenoidectomía , Niño , Preescolar , Reacciones Falso Negativas , Reacciones Falso Positivas , Femenino , Humanos , Lactante , Masculino , Ventilación del Oído Medio , Otitis Media/fisiopatología , Otitis Media/terapia , Otoscopía , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Tonsilectomía
19.
Toxicon ; 102: 74-80, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26079952

RESUMEN

A fluorometric assay was developed to semi-quantify co-purified polyketide prymnesins-1 and -2 (PPs) from Prymnesium parvum cultures. Evaluations performed throughout the growth cycle of 5 practical salinity unit (PSU) cultures detected relatively 8-10 × more PPs in the culture medium (exotoxins) than in cells (endotoxins). The [exotoxin] remained stable and relatively low until post-log growth, when they increased significantly. However, on a per-cell basis, [exotoxin] declined throughout log phase and subsequently increased dramatically during late- and post-log phases. The [endotoxin] remained stable until late- and post-log phases, when it achieved its highest level before declining sharply. Shaking cultures of strains from Texas, South Carolina and the United Kingdom displayed dramatically different [exotoxin] during post-log decline. Cultures adapted to 30 PSU had significantly lower [exotoxin] over the course of cultivation than those grown at 5 PSU. Phosphate limitation enhanced [exotoxin] on a per-cell basis, especially in late- and post-log cultures. Media containing streptomycin exhibited a ∼20% increase in [exotoxin] in post-log cultures vs. control treatments, but it had only negligible effects on endotoxin levels. Brefeldin A had minimal effects on [exotoxin], suggesting that the presence of PPs in the medium may be largely derived from cell lysis or some other passive means.


Asunto(s)
Células Cultivadas/química , Haptophyta/química , Lipoproteínas/análisis , Toxinas Marinas/análisis , Policétidos/análisis , Animales , Bioensayo , South Carolina , Texas , Reino Unido
20.
J Perinatol ; 35(10): 880-4, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26248131

RESUMEN

OBJECTIVE: The objective of this study was to compare the prevalence of home care practices in very to moderately preterm (VPT), late preterm (LPT) and term infants born in Massachusetts. STUDY DESIGN: Using 2007 to 2010 Massachusetts Pregnancy Risk Assessment Monitoring System data, births were categorized by gestational age (VPT: 23 to 33 weeks; LPT: 34 to 36 weeks; term: 37 to 42 weeks). Home care practices included breastfeeding initiation and continuation, and infant sleep practices (supine sleep position, sleeping in a crib, cosleeping in an adult bed). We developed multivariate models to examine the association of infant sleep practices and breastfeeding with preterm status, controlling for maternal sociodemographic characteristics. RESULTS: Supine sleep position was more prevalent among term infants compared with VPT and LPT infants (77.1%, 71.5%, 64.4%; P=0.02). In the adjusted model, LPT infants were less likely to be placed in supine sleep position compared with term infants (adjusted prevalence ratio=0.86; 95% confidence interval: 0.75 to 0.97). Breastfeeding initiation and continuation did not differ among preterm and term groups. Nearly 16% of VPT and 18% of LPT and term infants were not sleeping in cribs and 14% of LPT and term infants were cosleeping on an adult bed. CONCLUSION: Compared with term infants, LPT infants were less likely to be placed in supine sleep position after hospital discharge. A significant percent of preterm and term infants were cosleeping on an adult bed. Hospitals may consider improving their safe sleep education, particularly to mothers of LPT infants.


Asunto(s)
Servicios de Atención de Salud a Domicilio/tendencias , Madres/educación , Alta del Paciente , Adulto , Lactancia Materna , Estudios Transversales , Femenino , Edad Gestacional , Humanos , Lactante , Recien Nacido Extremadamente Prematuro , Recién Nacido , Masculino , Massachusetts , Análisis Multivariante , Embarazo , Estudios Retrospectivos , Sueño , Posición Supina , Nacimiento a Término
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA