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2.
Vasc Cell ; 8: 1, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26855770

RESUMEN

BACKGROUND: Biological evidence reported in the literature supports the role of CELSR1 as being essential for valvular function in murine lymphatics. Yet thus far, there have been no variants in CELSR1 associated with lymphatic dysfunction in humans. CASE PRESENTATION: In this report, a rare early inactivating mutation in CELSR1 is found to be causal for non-syndromic, lower extremity lymphedema in a family across three generations. Near-infrared fluorescence lymphatic imaging shows that instead of being propelled within the lumen of well-defined lymphatic vessels, lymph moved in regions of both legs in an unusual fashion and within sheet-like structures. CONCLUSION: CELSRI may be responsible for primary, non-syndromic lymphedema in humans.

4.
Lymphat Res Biol ; 10(1): 20-4, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22416911

RESUMEN

BACKGROUND: Absorbance of near-infrared (600-800 nm) light by the tissue components water, melanin, and hemoglobin is minimal. This property allows the use of near-infrared-emitting fluorophores for noninvasive, in vivo, real-time imaging of tissue, without the interference of autofluorescence experienced with imaging in other wavelength ranges. Near-infrared (NIR) fluorescence imaging has been used to noninvasively image lymphatic architecture and pumping function in animals, as well as in humans. The effects of different doses of a NIR dye, indocyanine green (ICG), on lymphatic function have been questioned. This study aims to address these concerns in the context of a mouse inguinal-to-axillary lymphatic imaging model. METHODS AND RESULTS: We measured lymph propulsive velocity and frequency using an imaging system composed of a laser diode for excitation of the dye, an image intensifier, and an intensified charge-coupled device (ICCD) camera to capture real-time images. At 0.32, 0.645, and 1.3 mM ICG, no significant differences in lymphatic propulsive velocity or frequency were observed. Additionally, the use of other NIR imaging agents did not result in significant differences. CONCLUSIONS: The use of different concentrations of ICG and the use of other near-infrared fluorophores for optical imaging of lymphatics does not significantly affect lymphatic propulsive velocity or frequency.


Asunto(s)
Colorantes/farmacocinética , Colorantes Fluorescentes/farmacocinética , Verde de Indocianina/farmacocinética , Sistema Linfático/metabolismo , Animales , Femenino , Procesamiento de Imagen Asistido por Computador , Linfografía , Ratones , Ratones Endogámicos C57BL , Espectroscopía Infrarroja Corta , Distribución Tisular
5.
Vaccine ; 25(47): 8021-35, 2007 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-17935840

RESUMEN

Oral, replication-competent Ad-HIV vaccines are advancing to human trials. Previous evaluation of protective efficacy in non-human primates has primarily followed upper respiratory tract administrations. Here we compared sequential oral (O/O) versus intranasal/oral (I/O) priming of rhesus macaques with Ad5 host range mutant-SIV recombinants expressing SIV env/rev, gag, and nef genes followed by boosting with SIV gp120 protein. Cellular immune responses in PBMC were stronger and more frequent after I/O administration. Both groups developed mucosal immunity, including memory cells in bronchial alveolar lavage, and gut-homing receptors on PBMC. Following intrarectal SIV(mac251) challenge, both groups exhibited equivalent, significant protection and robust post-challenge cellular immunity. Our results illustrate the promise of oral replication-competent Ad-recombinant vaccines. Pre-challenge PBMC ELISPOT and proliferative responses did not predict protection in the O/O group, highlighting the need for simple, non-invasive methods to reliably assess mucosal immunity.


Asunto(s)
Adenoviridae/genética , Replicación del ADN/genética , Vacunas contra el SIDAS/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/prevención & control , Virus de la Inmunodeficiencia de los Simios/genética , Virus de la Inmunodeficiencia de los Simios/inmunología , Administración Intranasal , Administración Oral , Animales , Células Cultivadas , Heces/virología , Humanos , Memoria Inmunológica/inmunología , Integrinas/metabolismo , Interferón gamma/metabolismo , Leucocitos/citología , Leucocitos/inmunología , Leucocitos/metabolismo , Macaca mulatta , Masculino , Mutación/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/inmunología , Proteínas Recombinantes/metabolismo , Vacunas contra el SIDAS/administración & dosificación , Comprimidos , Vacunas Sintéticas
6.
Heredity (Edinb) ; 98(1): 53-60, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17006531

RESUMEN

Several recent studies have shown that amphibian populations may exhibit high genetic subdivision in areas with recent fragmentation and urban development. Less is known about the potential for genetic differentiation in continuous habitats. We studied genetic differentiation of red-backed salamanders (Plethodon cinereus) across a 2-km transect through continuous forest in Virginia, USA. Mark-recapture studies suggest very little dispersal for this species, whereas homing experiments and post-Pleistocene range expansion both suggest greater dispersal abilities. We used six microsatellite loci to examine genetic population structure and differentiation between eight subpopulations of red-backed salamanders at distances from 200 m to 2 km. We also used several methods to extrapolate dispersal frequencies and test for sex-biased dispersal. We found small, but detectable differentiation among populations, even at distances as small as 200 m. Differentiation was closely correlated with distance and both Mantel tests and assignment tests were consistent with an isolation-by-distance model for the population. Extrapolations of intergenerational variance in spatial position (sigma(2)<15 m(2)) and pair-wise dispersal frequencies (4 Nm < 25 for plots separated by 300 m) both suggest limited gene flow. Additionally, tests for sex-biased dispersal imply that dispersal frequency is similarly low for both sexes. We suggest that these low levels of gene flow and the infrequent dispersal observed in mark-recapture studies may be reconciled with homing ability and range expansion if dispersing animals rarely succeed in breeding in saturated habitats, if dispersal is flexible depending on the availability of habitat, or if dispersal frequency varies across the geographic range of red-backed salamanders.


Asunto(s)
Ecosistema , Flujo Génico/genética , Salamandridae/genética , Animales , Variación Genética , Repeticiones de Microsatélite/genética , Movimiento , Dinámica Poblacional , Selección Genética , Factores Sexuales
7.
Sci Total Environ ; 379(2-3): 249-55, 2007 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-17055035

RESUMEN

This study describes the effects of Arsenic(III) and (V) on the growth and their uptake by the desert plant mesquite (Prosopis spp.). Seedlings were sown in agar-based medium containing a modified Hoagland's nutrient solution. After 1 week, the seedlings were transplanted to arsenic (As) treated agar media that contained 5 mgL(-1) of As either As(III) (As(2)O(3)) or As(V) (As(2)O(5)). The plants were harvested after 14 days of growth and sectioned into roots, stems, and leaves. After digestion, As concentrations in the roots, stems, and leaves were determined using inductively coupled plasma-optical emission spectroscopy (ICP-OES). Our results showed that the As concentrations from As(V) were significantly higher than the As concentrations from As(III) in all portions of the plant. Plants exposed to As(V) concentrated (mg As kg(-1) d wt) about 770+/-191, 326+/-94, and 119+/-18 in roots, stems, and leaves, respectively. X-ray absorption spectroscopy (XAS) showed that As(V) was reduced to As(III) inside the mesquite plant. In addition, greater than 90% of the As(III) found in the mesquite plants was bound to sulfur ligands in the roots, stems and leaves.


Asunto(s)
Arsénico/metabolismo , Prosopis/metabolismo , Contaminantes del Suelo/metabolismo , Biodegradación Ambiental , Hojas de la Planta/metabolismo , Raíces de Plantas/metabolismo , Tallos de la Planta/metabolismo , Análisis Espectral , Rayos X
8.
Virology ; 353(1): 83-98, 2006 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-16814356

RESUMEN

Previously, priming with replication-competent adenovirus-SIV multigenic vaccines and boosting with envelope subunits strongly protected 39% of rhesus macaques against rectal SIV(mac251) challenge. To evaluate protection durability, eleven of the protected and two SIV-infected unimmunized macaques that controlled viremia were re-challenged rectally with SIV(mac251). Strong protection was observed in 8/11 vaccinees, including two exhibiting <50 SIV RNA copies. Decreased viremia compared to naïve controls was observed in the other three. The SIV-infected unimmunized macaques modestly controlled viremia but exhibited CD4 counts < or =200, unlike the protected macaques. Durable protection was associated with significantly increased SIV-specific ELISPOT responses and lymphoproliferative responses to p27 at re-challenge. After CD8 depletion, 2 of 8 re-challenged, protected vaccinees maintained <50 SIV RNA copies; SIV RNA emerged in 6. Re-appearance of CD8 cells and restoration of SIV-specific cellular immunity coincided with viremia suppression. Overall, cellular immunity induced by vaccination and/or low-level, inapparent viremia post-first SIV(mac251) challenge, was associated with durable protection against re-challenge.


Asunto(s)
Adenoviridae/genética , Linfocitos T CD8-positivos/inmunología , Vacunas contra el SIDAS/administración & dosificación , Síndrome de Inmunodeficiencia Adquirida del Simio/prevención & control , Virus de la Inmunodeficiencia de los Simios/inmunología , Adenoviridae/inmunología , Administración Rectal , Animales , Inmunidad Celular , Inmunización Secundaria , Macaca mulatta , ARN Viral/análisis , Proteínas Recombinantes de Fusión/inmunología , Vacunas contra el SIDAS/genética , Vacunas contra el SIDAS/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/virología , Virus de la Inmunodeficiencia de los Simios/aislamiento & purificación , Factores de Tiempo , Vacunación , Vacunas Sintéticas/administración & dosificación , Viremia , Replicación Viral
9.
Int J Phytoremediation ; 6(3): 195-207, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15554473

RESUMEN

Experimental results have shown that the desert plant species mesquite (Prosopis spp.) is capable of accumulating high levels of lead in the roots, translocating it to the aerial portion of the plant. One-week-old mesquite seedlings were treated for 7 d in a hydroponic culture using a modified Hoagland solution. Six treatments were used; three treatments contained only Pb [as Pb(NO3)2] at 25-, 50-, and 75-mg L(-1) levels and three treatments contained the same levels of Pb, but with equimolar concentrations of disodium ethylenediamine tetraacetic acid (EDTA). Our results showed that the plants exposed to 25-, 50-, and 75-mg Pb L(-1) treatments without EDTA concentrated in stems 524, 3726, and 1417 mg kg(-1), respectively. However, the plants treated with Pb-EDTA concentrated in stems 480-, 607-, and 1247-mg Pb kg(-1) for the 25-, 50-, and 75-mg Pb L(-1) treatments, respectively. Results for the roots followed a similar trend; without EDTA the Pb levels ranged from 16,055, 89,935, and 63,396 for the 25-, 50-, and 75-mg Pb L(-1) treatments, respectively, and with EDTA these levels were 9,562, 49,902, and 39,181 mg kg(-1) for the three treatments. However, the addition of EDTA increased lead movement to the leaves. The levels of Pb without EDTA were 20, 35, and 51 mg kg(-1) for the 25-, 50-, and 75-mg Pb L(-1) levels, respectively. Treatments with EDTA showed uptake levels of 105, 124, and 313 for the 25-, 50-, and 75-mg Pb L(-1) treatments. Further, the percent Pb in dry leaf tissues for all EDTA treatments were greater than 0.1%. However, only the 25-mg Pb L(-1) treatment was greater than 0.1%, compared to 0.04 and 0.08% for the 50- and 75-mg Pb L(-1) treatments, respectively. Preliminary transmission and scanning electron microscopy corroborate the presence of lead.


Asunto(s)
Quelantes/farmacología , Ácido Edético/farmacología , Sustancias Peligrosas/farmacocinética , Plomo/farmacocinética , Prosopis/metabolismo , Biodegradación Ambiental , Quelantes/administración & dosificación , Clima Desértico , Relación Dosis-Respuesta a Droga , Ácido Edético/administración & dosificación , Sustancias Peligrosas/administración & dosificación , Humanos , Plomo/administración & dosificación , Componentes Aéreos de las Plantas/metabolismo , Raíces de Plantas/metabolismo , Prosopis/ultraestructura , Plantones/metabolismo
10.
Environ Sci Technol ; 37(9): 1859-64, 2003 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-12775058

RESUMEN

Chromium (Cr) is a well-established carcinogen that is a contaminant at half of the EPA Superfund sites in the United States. Two separate studies were performed to investigate the possibility that mesquite (Prosopis spp.), which is an indigenous desert plant species, can remove Cr from the environment via active transport systems to the aerial portions of the plant. The first study was performed by growing mesquite on solid media (agar) at Cr(VI) concentrations of 75 and 125 ppm. The accumulation found in the leaves under the present conditions indicated that mesquite could be classified as a hyperaccumulator of chromium. The second study was conducted to investigate the differences between the type of Cr ligand involved in Cr uptake with agar and hydroponic cultures. We used X-ray absorption spectroscopy (XAS) to determine the mechanisms involved in the uptake and binding of Cr(VI) in live mesquite tissue. The XAS results for this study showed that some of the supplied Cr(VI) was uptaken by the mesquite roots; however, the data analyses of the plant tissues demonstrated that it was fully reduced to Cr(III) in the leaf tissues. Experiments are currently being performed to evaluate the behavior of the Mesquite plant using lower Cr concentrations.


Asunto(s)
Carcinógenos Ambientales/farmacocinética , Cromo/farmacocinética , Prosopis/fisiología , Contaminantes del Suelo/farmacocinética , Biodegradación Ambiental , Carcinógenos Ambientales/química , Cromo/química , Oxidación-Reducción , Raíces de Plantas , Prosopis/química , Análisis Espectral
11.
J Food Prot ; 64(6): 807-12, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11403130

RESUMEN

The objective of this study was to determine the effectiveness of the combined use of an inside-outside-bird-washer for the removal of visible contamination and an online acidified sodium chlorite (ASC) spray system in reducing microbial levels on contaminated poultry carcasses. Specifically, we attempted to determine if this technique (referred to as continuous online processing [COP]) would (i) eliminate the need for offline reprocessing of contaminated carcasses, (ii) meet Zero Fecal Tolerance standards, and (iii) attain significant reductions in titers of some of the commonly found bacterial species. Carcasses were sampled for Ercherichia coli, Salmonella, and Campylobacter at five stations along the processing lines in a series of five commercial plant studies to compare the efficacy of the COP system to that of offline processing. The microbiological quality of fecally contaminated carcasses was found to be significantly better following COP treatment (E. coli, 0.59 log10 CFU/ml; Salmonella, 10.0% incidence) than after standard offline reprocessing (E. coli, 2.37 log10 CFU/ml; Salmonella, 31.6% incidence). Zero Fecal Tolerance requirements were met by all but 2 (0.2%) of the 1.127 carcasses following COP. COP also significantly reduced the titers of Campylobacter; residual titers were 1.14 log10 CFU/ml (49.1% incidence) following COP, compared to 2.89 log10 CFU/ml (73.2% incidence) in carcasses that underwent offline reprocessing. These results support the combined use of an inside-outside-bird-washer for the removal of visible contamination and an online ASC spray system to reduce microbial levels in commercially processed poultry.


Asunto(s)
Pollos/microbiología , Cloruros/farmacología , Heces/microbiología , Contaminación de Alimentos/prevención & control , Manipulación de Alimentos/métodos , Animales , Campylobacter/aislamiento & purificación , Recuento de Colonia Microbiana , Desinfectantes , Escherichia coli/aislamiento & purificación , Concentración de Iones de Hidrógeno , Salmonella/aislamiento & purificación , Resultado del Tratamiento
12.
Sleep ; 24(4): 385-91, 2001 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-11403522

RESUMEN

STUDY OBJECTIVE: To determine if the combination of scheduled sleep periods and stimulant medications were more effective than stimulant medications alone in controlling the excessive daytime sleepiness experienced by narcoleptic patients. DESIGN: Twenty-nine treated narcoleptic subjects were randomly assigned to one of three treatment groups: 1) two 15-minute naps per day; 2) a regular schedule for nocturnal sleep; or 3) a combination of scheduled naps and regular bedtimes. Measures of symptom severity and unscheduled daytime were obtained at baseline and at the end of the two-week treatment period, using the Narcolepsy Symptom Status Questionnaire (NSSQ) and 24-hour ambulatory polysomnographic monitoring. No alterations were made in stimulant medications during the study period. SETTING: N/A. PATIENTS OR PARTICIPANTS: N/A. INTERVENTIONS: N/A. MEASUREMENTS AND RESULTS: The addition of two-15 minute naps did not alter either symptom severity or the duration of unscheduled daytime sleep. Regular times for nocturnal sleep reduced perceived symptom severity, but did not reduce the amount of unscheduled daytime sleep. Only the combination of scheduled naps and regular nocturnal sleep times, significantly reduced both symptom severity and the amount of unscheduled daytime sleep in treated narcoleptic subjects. The type of sleep schedule prescribed, however, was less important than the severity of the patients' pre-treatment daytime sleepiness. Subjects with severe daytime sleepiness benefited from the addition of scheduled sleep periods, while those who were only moderately sleepy or able to maintain alertness did not benefit from scheduled sleep periods. CONCLUSIONS: Scheduled sleep periods are helpful for only those patients who remain profoundly sleepy despite stimulant medications and should not be prescribed for all patients with narcolepsy.


Asunto(s)
Ritmo Circadiano/fisiología , Trastornos de Somnolencia Excesiva/prevención & control , Narcolepsia/prevención & control , Sueño/fisiología , Adulto , Trastornos de Somnolencia Excesiva/complicaciones , Femenino , Humanos , Masculino , Narcolepsia/complicaciones , Polisomnografía , Encuestas y Cuestionarios
13.
Bull Hist Med ; 75(2): 254-89, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11423683

RESUMEN

From their beginning American railroads developed medical arrangements to care for the large number of workers and passengers they killed or injured. After the Civil War, both labor unrest and liability concerns led them to expand and formalize these arrangements, and three forms of organization arose. Western roads, facing an almost complete lack of medical facilities, developed employee-funded hospital organizations. In the east, companies created medical organizations under a salaried chief surgeon and contracted with local physicians to provide care. A third model, pioneered by the Baltimore & Ohio Railroad in the 1880s, devised a beneficial society that provided medical care and compensation for injured workers. Although these organizations involved both contract practice and group hospitalization, the AMA seems to have ignored them. In the 1880s railroad physicians developed their own organizations, including the National Association of Railway Surgeons, in which they discussed problems of professionalization and such medical matters as "railway spine." Concern with costs and labor turnover also led the carriers into preventive medicine. Some roads provided smallpox and typhoid vaccinations, campaigned against malaria, improved passenger-car sanitation, required physical examinations of their employees, and trained them in first aid. By World War I, railroad medical organizations provided care to nearly two million employees and employment to about 10 percent of all physicians.


Asunto(s)
Vías Férreas/historia , Sociedades Médicas/historia , Accidentes , Historia del Siglo XIX , Historia del Siglo XX , Hospitales/historia , Humanos , Fiebre Tifoidea/historia , Estados Unidos
14.
Sleep Med ; 2(3): 185-194, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11311681

RESUMEN

Background/objective: Since reports of the effects of cerebral hemispheric stroke on sleep architecture are rare and contradictory, we prospectively studied 24 patients with first acute supratentorial, extra-thalamic stroke.Methods: We assessed stroke severity, topography, and volume (on brain MRI). Sleep electroencephalogram recordings were performed a mean of 12 days after stroke onset, and scored for sleep stages over the healthy hemisphere. Sleep spindles and sawtooth waves were analyzed over both hemispheres. Data were compared with those of 17 age and gender-matched patients with normal brain imaging.Results: Compared to controls, stroke patients had lower total sleep time (P<0.01), lower sleep efficiency (P=0.02), and reduced amounts of NREM sleep stages 2-4 (P=0.02). Sleep spindles and sawtooth waves were often bilaterally reduced in patients with stroke volumes >25 ml. Abnormalities of REM sleep were more common in sleep studies performed within 3 days after stroke onset. Compared to patients with poor outcome, those with good outcome had higher sleep efficiency (P<0.01), more sleep time (P=0.02), and more NREM sleep stage 2 (P<0.01).Conclusion: Acute hemispheric stroke is accompanied by sleep EEG changes over the healthy hemisphere that correlate with stroke severity. These findings support the hypothesis that the cerebral hemispheres participate in the control of sleep.

15.
Am J Psychiatry ; 158(3): 399-404, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11229980

RESUMEN

OBJECTIVE: This study was an investigation of the frequencies of insomnia and its self-medication with alcohol in a group of alcoholic patients, as well as the relationship of these variables to alcoholic relapse. METHOD: The subjects were 172 men and women receiving treatment for alcohol dependence. They completed a sleep questionnaire, measures of alcohol problem severity and depression severity, and polysomnography after at least 2 weeks of abstinence. RESULTS: On the basis of eight items from the Sleep Disorders Questionnaire, 61% of the subjects were classified as having symptomatic insomnia during the 6 months before treatment entry. Compared to patients without insomnia, patients with insomnia were more likely to report frequent alcohol use for sleep (55% versus 28%), had significantly worse polysomnographic measures of sleep continuity, and had more severe alcohol dependence and depression. Among 74 alcoholics who were followed a mean of 5 months after treatment, 60% with baseline insomnia versus 30% without baseline insomnia relapsed to any use of alcohol, a significant difference. Insomnia remained a robust predictor of relapse after application of logistic regression analysis to control for other variables. A history of self-medicating insomnia with alcohol did not significantly predict subsequent relapse. CONCLUSIONS: The majority of alcoholic patients entering treatment reported insomnia symptoms. Given the potential link between insomnia and relapse, routine questions about sleep in clinical and research settings are warranted.


Asunto(s)
Consumo de Bebidas Alcohólicas/epidemiología , Alcoholismo/epidemiología , Etanol/administración & dosificación , Automedicación , Trastornos del Inicio y del Mantenimiento del Sueño/tratamiento farmacológico , Adulto , Alcoholismo/diagnóstico , Alcoholismo/psicología , Enfermedad Crónica , Comorbilidad , Trastorno Depresivo/diagnóstico , Trastorno Depresivo/tratamiento farmacológico , Trastorno Depresivo/epidemiología , Etanol/uso terapéutico , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Polisomnografía/estadística & datos numéricos , Escalas de Valoración Psiquiátrica/estadística & datos numéricos , Recurrencia , Análisis de Regresión , Índice de Severidad de la Enfermedad , Trastornos del Inicio y del Mantenimiento del Sueño/diagnóstico , Trastornos del Inicio y del Mantenimiento del Sueño/epidemiología , Encuestas y Cuestionarios , Resultado del Tratamiento
16.
Neurology ; 55(9): 1410-2, 2000 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-11087796

RESUMEN

REM sleep behavior disorder (RBD) is a possible herald of neurodegenerative disorders with parkinsonism. The authors determined the density of striatal dopaminergic terminals with [11C]dihydrotetrabenazine PET in six elderly subjects with chronic idiopathic RBD and 19 age-appropriate controls. In subjects with RBD, there were significant reductions in striatal [11C]dihydrotetrabenazine binding, particularly in the posterior putamen.


Asunto(s)
Cuerpo Estriado/diagnóstico por imagen , Dopamina/análisis , Trastorno de la Conducta del Sueño REM/diagnóstico por imagen , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tomografía Computarizada de Emisión
17.
Am J Physiol Lung Cell Mol Physiol ; 279(6): L1047-57, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11076794

RESUMEN

Tumor necrosis factor-alpha (TNF) is implicated as an important proinflammatory cytokine in asthma. We evaluated mice deficient in TNF receptor 1 (TNFR1) and TNFR2 [TNFR(-/-) mice] in a murine model of allergic inflammation and found that TNFR(-/-) mice had comparable or accentuated responses compared with wild-type [TNFR(+/+)] mice. The responses were consistent among multiple end points. Airway responsiveness after methacholine challenge and bronchoalveolar lavage (BAL) fluid leukocyte and eosinophil numbers in TNFR(-/-) mice were equivalent or greater than those observed in TNFR(+/+) mice. Likewise, serum and BAL fluid IgE; lung interleukin (IL)-2, IL-4, and IL-5 levels; and lung histological lesion scores were comparable or greater in TNFR(-/-) mice compared with those in TNFR(+/+) mice. TNFR(+/+) mice chronically treated with anti-murine TNF antibody had BAL fluid leukocyte numbers and lung lesion scores comparable to control antibody-treated mice. These results suggest that, by itself, TNF does not have a critical proinflammatory role in the development of allergic inflammation in this mouse model and that the production of other cytokines associated with allergic disease may compensate for the loss of TNF bioactivity in the TNFR(-/-) mouse.


Asunto(s)
Asma/inmunología , Neumonía/inmunología , Receptores del Factor de Necrosis Tumoral/genética , Receptores del Factor de Necrosis Tumoral/inmunología , Aerosoles , Animales , Líquido del Lavado Bronquioalveolar/química , Líquido del Lavado Bronquioalveolar/inmunología , Modelos Animales de Enfermedad , Inmunoglobulina E/sangre , Inmunoglobulina G/sangre , Interferón gamma/análisis , Interleucina-2/análisis , Interleucina-4/análisis , Interleucina-5/análisis , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ovalbúmina/inmunología , Ovalbúmina/farmacología , Hipersensibilidad Respiratoria/inmunología , Transducción de Señal/inmunología , Subgrupos de Linfocitos T/inmunología , Factor de Necrosis Tumoral alfa/análisis
18.
Neuron ; 27(3): 469-74, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11055430

RESUMEN

Murine and canine narcolepsy can be caused by mutations of the hypocretin (Hcrt) (orexin) precursor or Hcrt receptor genes. In contrast to these animal models, most human narcolepsy is not familial, is discordant in identical twins, and has not been linked to mutations of the Hcrt system. Thus, the cause of human narcolepsy remains unknown. Here we show that human narcoleptics have an 85%-95% reduction in the number of Hcrt neurons. Melanin-concentrating hormone (MCH) neurons, which are intermixed with Hcrt cells in the normal brain, are not reduced in number, indicating that cell loss is relatively specific for Hcrt neurons. The presence of gliosis in the hypocretin cell region is consistent with a degenerative process being the cause of the Hcrt cell loss in narcolepsy.


Asunto(s)
Encéfalo/patología , Proteínas Portadoras , Péptidos y Proteínas de Señalización Intracelular , Narcolepsia/patología , Neuronas/patología , Neuropéptidos , Neurotransmisores/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Astrocitos/metabolismo , Astrocitos/patología , Encéfalo/metabolismo , Recuento de Células , Femenino , Proteína Ácida Fibrilar de la Glía/metabolismo , Gliosis/patología , Humanos , Hormonas Hipotalámicas/metabolismo , Hipotálamo/metabolismo , Hipotálamo/patología , Inmunohistoquímica , Masculino , Melaninas/metabolismo , Persona de Mediana Edad , Narcolepsia/etiología , Neuronas/metabolismo , Orexinas , Hormonas Hipofisarias/metabolismo
19.
Nat Med ; 6(9): 991-7, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10973318

RESUMEN

We explored the role of hypocretins in human narcolepsy through histopathology of six narcolepsy brains and mutation screening of Hcrt, Hcrtr1 and Hcrtr2 in 74 patients of various human leukocyte antigen and family history status. One Hcrt mutation, impairing peptide trafficking and processing, was found in a single case with early onset narcolepsy. In situ hybridization of the perifornical area and peptide radioimmunoassays indicated global loss of hypocretins, without gliosis or signs of inflammation in all human cases examined. Although hypocretin loci do not contribute significantly to genetic predisposition, most cases of human narcolepsy are associated with a deficient hypocretin system.


Asunto(s)
Química Encefálica/genética , Proteínas Portadoras , Péptidos y Proteínas de Señalización Intracelular , Mutación , Narcolepsia/genética , Neuropéptidos/genética , Receptores de Neuropéptido/genética , Adulto , Edad de Inicio , Anciano , Anciano de 80 o más Años , Corteza Cerebral/química , Femenino , Pruebas Genéticas , Humanos , Hipotálamo/química , Hipotálamo/citología , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Neuropéptidos/análisis , Neurotransmisores/genética , Receptores de Orexina , Orexinas , Puente/química , Procesamiento Proteico-Postraduccional , Receptores Acoplados a Proteínas G , Distribución Tisular , Población Blanca
20.
J Food Prot ; 63(8): 1087-92, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10945585

RESUMEN

An acidified sodium chlorite (ASC) solution was investigated for its antimicrobial effects on broiler carcasses processed under conditions similar to those used in U.S. commercial poultry facilities. Of particular interest was the ability of the ASC solution to reduce natural bioburden in a prechill procedure. A number of parameters such as pretreatment washing of carcasses with water (no wash versus water wash), ASC concentration (500, 850, and 1,200 ppm), method of application (spray versus dip), and method of acid activation (phosphoric acid versus citric acid) were explored to evaluate disinfection conditions. ASC dip solutions (18.9 liters) were freshly prepared for groups of five prechill eviscerated carcasses per treatment (n = 10 carcasses). ASC treatment was shown to be an effective method for significantly reducing naturally occurring microbial contamination on carcasses. Reductions following immersion dipping were demonstrated at all disinfectant concentrations for total aerobes (82.9 to 90.7%), Escherichia coli (99.4 to 99.6%), and total coliforms (86.1 to 98.5%). Additionally, testing showed that ASC solutions maintained stable pH and minimal chlorite ion concentration deviations throughout each treatment. The results of the parameter evaluations indicated that maximal antimicrobial activity was achieved in carcasses that were prewashed and then exposed to a 5-s dip in a solution containing phosphoric acid- or citric acid-activated ASC. At 1,200 ppm ASC, a mild but transitory whitening of the skin was noted on dipped carcasses. The results support the methods currently approved by the U.S. Department of Agriculture for the use of ASC solutions as a prechill antimicrobial intervention in U.S. poultry processing plants.


Asunto(s)
Bacterias Aerobias/efectos de los fármacos , Pollos/microbiología , Cloruros/farmacología , Desinfección/métodos , Enterobacteriaceae/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Animales , Bacterias Aerobias/crecimiento & desarrollo , Bacterias Aerobias/aislamiento & purificación , Recuento de Colonia Microbiana , Enterobacteriaceae/crecimiento & desarrollo , Enterobacteriaceae/aislamiento & purificación , Escherichia coli/crecimiento & desarrollo , Escherichia coli/aislamiento & purificación , Manipulación de Alimentos , Microbiología de Alimentos , Concentración de Iones de Hidrógeno
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