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1.
Eplasty ; 22: ic7, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35706823

RESUMEN

What is rhinophyma? Why might an individual seek treatment of rhinophyma? Are surgical or nonsurgical methods preferred when treating rhinophyma? What are the advantages and disadvantages to common surgical techniques in the treatment of rhinophyma?

2.
Am J Physiol Heart Circ Physiol ; 319(5): H1059-H1068, 2020 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-33036546

RESUMEN

The prevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) quickly reached pandemic proportions, and knowledge about this virus and coronavirus disease 2019 (COVID-19) has expanded rapidly. This review focuses primarily on mechanisms that contribute to acute cardiac injury and dysfunction, which are common in patients with severe disease. The etiology of cardiac injury is multifactorial, and the extent is likely enhanced by preexisting cardiovascular disease. Disruption of homeostatic mechanisms secondary to pulmonary pathology ranks high on the list, and there is growing evidence that direct infection of cardiac cells can occur. Angiotensin-converting enzyme 2 (ACE2) plays a central role in COVID-19 and is a necessary receptor for viral entry into human cells. ACE2 normally not only eliminates angiotensin II (Ang II) by converting it to Ang-(1-7) but also elicits a beneficial response profile counteracting that of Ang II. Molecular analyses of single nuclei from human hearts have shown that ACE2 is most highly expressed by pericytes. Given the important roles that pericytes have in the microvasculature, infection of these cells could compromise myocardial supply to meet metabolic demand. Furthermore, ACE2 activity is crucial for opposing adverse effects of locally generated Ang II, so virus-mediated internalization of ACE2 could exacerbate pathology by this mechanism. While the role of cardiac pericytes in acute heart injury by SARS-CoV-2 requires investigation, expression of ACE2 by these cells has broader implications for cardiac pathophysiology.


Asunto(s)
Betacoronavirus/patogenicidad , Infecciones por Coronavirus/enzimología , Cardiopatías/enzimología , Peptidil-Dipeptidasa A/metabolismo , Pericitos/enzimología , Neumonía Viral/enzimología , Internalización del Virus , Enzima Convertidora de Angiotensina 2 , Animales , COVID-19 , Infecciones por Coronavirus/virología , Cardiopatías/fisiopatología , Cardiopatías/virología , Interacciones Huésped-Patógeno , Humanos , Pandemias , Pericitos/virología , Neumonía Viral/virología , SARS-CoV-2
3.
Nat Med ; 26(2): 289-299, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31988461

RESUMEN

Young-onset Parkinson's disease (YOPD), defined by onset at <50 years, accounts for approximately 10% of all Parkinson's disease cases and, while some cases are associated with known genetic mutations, most are not. Here induced pluripotent stem cells were generated from control individuals and from patients with YOPD with no known mutations. Following differentiation into cultures containing dopamine neurons, induced pluripotent stem cells from patients with YOPD showed increased accumulation of soluble α-synuclein protein and phosphorylated protein kinase Cα, as well as reduced abundance of lysosomal membrane proteins such as LAMP1. Testing activators of lysosomal function showed that specific phorbol esters, such as PEP005, reduced α-synuclein and phosphorylated protein kinase Cα levels while increasing LAMP1 abundance. Interestingly, the reduction in α-synuclein occurred through proteasomal degradation. PEP005 delivery to mouse striatum also decreased α-synuclein production in vivo. Induced pluripotent stem cell-derived dopaminergic cultures reveal a signature in patients with YOPD who have no known Parkinson's disease-related mutations, suggesting that there might be other genetic contributions to this disorder. This signature was normalized by specific phorbol esters, making them promising therapeutic candidates.


Asunto(s)
Células Madre Pluripotentes Inducidas/metabolismo , Mutación , Enfermedad de Parkinson/genética , Enfermedad de Parkinson/metabolismo , Enfermedad de Parkinson/terapia , Adulto , Edad de Inicio , Animales , Diferenciación Celular/genética , Dopamina/metabolismo , Neuronas Dopaminérgicas/metabolismo , Humanos , Leucocitos Mononucleares/citología , Lisosomas/metabolismo , Proteínas de la Membrana/metabolismo , Ratones , Ratones Endogámicos C57BL , Técnicas de Placa-Clamp , Fenotipo , Ésteres del Forbol , Fosforilación , Proteómica , Transcriptoma , alfa-Sinucleína/metabolismo
4.
Methods Mol Biol ; 1799: 11-26, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29956140

RESUMEN

Helminth parasites infect over 2 billion people worldwide resulting in huge global health and economic burden. Helminths typically stimulate Type 2 immune responses and excel at manipulating or suppressing host-immune responses resulting in chronic infections that can last for years to decades. Alongside the importance for the development of helminth treatments and vaccines, studying helminth immunity has unraveled many fundamental aspects of Type 2 immunity and immune regulation with implications for the treatment of autoimmunity and Type 2-mediated diseases, such as allergies. Here we describe the maintenance and use of Litomosoides sigmodontis, a murine model for studying host-parasite interactions, Type 2 immunity, and vaccines to tissue-dwelling filarial nematodes, which in humans cause lymphatic filariasis (e.g., Brugia malayi) and onchocerciasis (Onchocerca volvulus).


Asunto(s)
Filariasis/inmunología , Filariasis/parasitología , Filarioidea , Interacciones Huésped-Parásitos/inmunología , Inmunidad , Animales , Antígenos Helmínticos/inmunología , Modelos Animales de Enfermedad , Femenino , Ratones , Ácaros/parasitología
5.
J Vet Intern Med ; 31(3): 734-742, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28425145

RESUMEN

BACKGROUND: Gastroesophageal reflux (GER) is poorly characterized in anesthetized cats, but can cause aspiration pneumonia, esophagitis, and esophageal stricture formation. OBJECTIVE: To determine whether pre-anesthetic orally administered omeprazole increases gastric and esophageal pH and increases serum gastrin concentrations in anesthetized cats, and to determine the prevalence of GER using combined multichannel impedance and pH monitoring. ANIMALS: Twenty-seven healthy cats undergoing elective dental procedures. METHODS: Prospective, double-masked, placebo-controlled, randomized clinical trial. Cats were randomized to receive 2 PO doses of omeprazole (1.45-2.20 mg/kg) or an empty gelatin capsule placebo 18-24 hours and 4 hours before anesthetic induction. Blood for measurement of serum gastrin concentration was collected during anesthetic induction. An esophageal pH/impedance catheter was utilized to continuously measure esophageal pH and detect GER throughout anesthesia. RESULTS: Mean gastric pH in the cats that received omeprazole was 7.2 ± 0.4 (range, 6.6-7.8) and was significantly higher than the pH in cats that received the placebo 2.8 ± 1.0 (range, 1.3-4.1; P < .001). Omeprazole administration was not associated with a significant increase in serum gastrin concentration (P = .616). Nine of 27 cats (33.3%) had ≥1 episode of GER during anesthesia. CONCLUSIONS AND CLINICAL RELEVANCE: Pre-anesthetic administration of 2 PO doses of omeprazole at a dosage of 1.45-2.20 mg/kg in cats was associated with a significant increase in gastric and esophageal pH within 24 hours, but was not associated with a significant increase in serum gastrin concentration. Prevalence of reflux events in cats during anesthesia was similar to that of dogs during anesthesia.


Asunto(s)
Antiulcerosos/uso terapéutico , Enfermedades de los Gatos/prevención & control , Reflujo Gastroesofágico/veterinaria , Omeprazol/uso terapéutico , Administración Oral , Anestesia/veterinaria , Animales , Antiulcerosos/administración & dosificación , Antiulcerosos/farmacología , Gatos , Esófago/efectos de los fármacos , Femenino , Reflujo Gastroesofágico/prevención & control , Concentración de Iones de Hidrógeno/efectos de los fármacos , Masculino , Omeprazol/administración & dosificación , Omeprazol/farmacología , Estudios Prospectivos , Resultado del Tratamiento
6.
Case Reports Immunol ; 2015: 619867, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26491579

RESUMEN

Sarcoidosis is a multisystem granulomatous disorder. Neurological manifestations as a presenting symptom are relatively rare. A 26-year-old male presented with a five-week history of headache suggestive of raised intracranial pressure. He subsequently developed transient episodes of mild right-sided hemiparesis and numbness. Magnetic resonance imaging (MRI) of brain revealed widespread inflammatory white matter lesions, an ischaemic focus in the left corona radiata, and widespread microhaemorrhages consistent with a more diffuse vasculopathy. Serum angiotensin-converting enzyme (ACE) level was normal. Lumbar puncture revealed an elevated opening pressure (36 cmH2O) and inflammatory cerebrospinal fluid (CSF). Computerised tomography (CT) of chest, abdomen, and pelvis revealed widespread lymphadenopathy and biopsy of axillary lymph nodes revealed the presence of noncaseating granulomata in keeping with systemic sarcoidosis. The patient responded well to corticosteroids. This case highlights the importance of considering sarcoidosis to be a rare but potentially treatable cause of stroke in younger patients.

7.
Vet Comp Oncol ; 12(4): 258-65, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22985095

RESUMEN

Oral squamous cell carcinoma (OSCC) and canine acanthomatous ameloblastoma (CAA) represent two epithelium-derived neoplasms that affect the oral cavity of dogs. The expression of cytokeratins (CKs) and calretinin has been previously established in the canine tooth bud and odontogenic tumours. The aim of this study was to characterize the CK and calretinin expression profile of OSCC in comparison to CAA and canine tooth bud tissues. Samples from 15 OSCC and 15 CAA cases, as well as 6 tooth buds and 2 normal gingival tissues were examined. OSCC CK expression was consistent with the CK expression profile of CAA and canine tooth bud tissue. Calretinin was positively expressed in 10 of 15 OSCC cases, with 5 cases demonstrating high staining intensity. Only 2 of 15 CAA cases demonstrated mild-moderate staining intensity. The statistically significant difference in staining pattern and intensity of calretinin in OSCC and CAA can help distinguish between these two tumour types.


Asunto(s)
Ameloblastoma/veterinaria , Calbindina 2/metabolismo , Carcinoma de Células Escamosas/veterinaria , Enfermedades de los Perros/metabolismo , Neoplasias Maxilomandibulares/veterinaria , Queratinas/metabolismo , Neoplasias de la Boca/veterinaria , Ameloblastoma/metabolismo , Ameloblastoma/patología , Animales , Anticuerpos Monoclonales , California , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patología , Enfermedades de los Perros/patología , Perros , Inmunohistoquímica/veterinaria , Neoplasias Maxilomandibulares/metabolismo , Neoplasias Maxilomandibulares/patología , Neoplasias de la Boca/metabolismo , Neoplasias de la Boca/patología , Diente/patología , Universidades
8.
Tree Physiol ; 32(7): 880-93, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22684354

RESUMEN

Hydraulic traits were studied for six Nothofagus species from South America (Argentina and Chile), and for three of these species two populations were studied. The main goal was to determine if properties of the water conductive pathway in stems and leaves are functionally coordinated and to assess if leaves are more vulnerable to cavitation than stems, consistent with the theory of hydraulic segmentation along the vascular system of trees in ecosystems subject to seasonal drought. Vulnerability to cavitation, hydraulic conductivity of stems and leaves, leaf water potential, wood density and leaf water relations were examined. Large variations in vulnerability to cavitation of stems and leaves were observed across populations and species, but leaves were consistently more vulnerable than stems. Water potential at 50% loss of maximum hydraulic efficiency (P(50)) ranged from -0.94 to -2.44 MPa in leaves and from -2.6 to -5.3 MPa in stems across species and populations. Populations in the driest sites had sapwood and leaves more vulnerable to cavitation than those grown in the wettest sites. Stronger diurnal down-regulation in leaf hydraulic conductance compared with stem hydraulic conductivity apparently has the function to slow down potential water loss in stems and protect stem hydraulics from cavitation. Species-specific differences in wood density and leaf hydraulic conductance (K(Leaf)) were observed. Both traits were functionally related: species with higher wood density had lower K(Leaf). Other stem and leaf hydraulic traits were functionally coordinated, resulting in Nothofagus species with an efficient delivery of water to the leaves. The integrity of the more expensive woody portion of the water transport pathway can thus be maintained at the expense of the replaceable portion (leaves) of the stem-leaf continuum under prolonged drought. Compensatory adjustments between hydraulic traits may help to decrease the rate of embolism formation in the trees more vulnerable to cavitation.


Asunto(s)
Magnoliopsida/fisiología , Hojas de la Planta/fisiología , Tallos de la Planta/fisiología , Agua/metabolismo , Altitud , Transporte Biológico , Humedad , Lluvia , Suelo , América del Sur , Especificidad de la Especie , Temperatura , Madera/fisiología
9.
J Perinatol ; 32(6): 418-24, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21760585

RESUMEN

OBJECTIVE: Dietary carotenoids (lutein, lycopene and ß-carotene) may be important in preventing or ameliorating prematurity complications. Little is known about carotenoid status or effects of supplementation. STUDY DESIGN: This randomized controlled multicenter trial compared plasma carotenoid levels among preterm infants (n=203, <33 weeks gestational age) fed diets with and without added lutein, lycopene and ß-carotene with human milk (HM)-fed term infants. We assessed safety and health. RESULT: Plasma carotenoid levels were higher in the supplemented group at all time points (P<0.0001) and were similar to those of term HM-fed infants. Supplemented infants had lower plasma C-reactive protein (P<0.001). Plasma lutein levels correlated with the full field electroretinogram-saturated response amplitude in rod photoreceptors (r=0.361, P=0.05). The supplemented group also showed greater rod photoreceptor sensitivity (least squares means 6.1 vs 4.1; P<0.05). CONCLUSION: Carotenoid supplementation for preterm infants raises plasma concentrations to those observed in HM-fed term infants. Carotenoid supplementation may decrease inflammation. Our results point to protective effects of lutein on preterm retina health and maturation.


Asunto(s)
Carotenoides/uso terapéutico , Suplementos Dietéticos/efectos adversos , Enfermedades del Prematuro/tratamiento farmacológico , Inflamación/tratamiento farmacológico , Retina/efectos de los fármacos , Visión Ocular/efectos de los fármacos , Proteína C-Reactiva/análisis , Carotenoides/efectos adversos , Carotenoides/sangre , Método Doble Ciego , Electrorretinografía , Femenino , Humanos , Recién Nacido , Recien Nacido Prematuro , Masculino , Retina/crecimiento & desarrollo
10.
Doc Ophthalmol ; 118(1): 69-77, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19030905

RESUMEN

This document, from the International Society for Clinical Electrophysiology of Vision (ISCEV), presents an updated and revised ISCEV Standard for clinical electroretinography (ERG). The parameters for flash stimulation and background adaptation have been tightened, and responses renamed to indicate the flash strength (in cd x s x m(-2)). The ISCEV Standard specifies five responses: (1) Dark-adapted 0.01 ERG (rod response); (2) Dark-adapted 3.0 ERG (combined rod-cone response); (3) Dark-adapted 3.0 oscillatory potentials; (4) Light-adapted 3.0 ERG (cone response); (5) Light-adapted 3.0 flicker (30 Hz flicker). An additional Dark-adapted 10.0 ERG or Dark-adapted 30.0 ERG response is recommended.


Asunto(s)
Electrorretinografía/instrumentación , Electrorretinografía/normas , Adaptación Ocular , Adulto , Anciano , Anciano de 80 o más Años , Calibración , Niño , Preescolar , Protocolos Clínicos/normas , Electrodos , Humanos , Lactante , Estimulación Luminosa/métodos , Proyectos de Investigación/normas , Estadística como Asunto/métodos , Terminología como Asunto
11.
Bull Entomol Res ; 97(5): 455-60, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17916264

RESUMEN

The emergence of resistance mechanisms to, and revocation of, many insecticides used in the control of the polyphagus aphid pest, Myzus persicae (Sulzer), has increased the pressure to develop novel approaches for the control of the pest in many crops. Kaolin-based particle films provide a physical barrier against insect pests and show considerable potential for controlling M. persicae. We conducted a series of laboratory experiments to investigate the mode of action of kaolin against aphids. The material appeared to have no direct effect on M. persicae; spraying adult aphids with aqueous kaolin suspension had no significant impact on their subsequent survival or reproduction on untreated plants. Similarly, when aphids were placed on kaolin-treated host-plants (Brassica oleracea), their performance (survival, growth rate and reproduction) was not significantly different from aphids on untreated plants. However, when M. persicae were given a choice between kaolin-treated and untreated (or water solvent-treated) leaf areas, both adults and nymphs exhibited a significant preference for non-kaolin-treated host-plant material. Rejection of kaolin-treated plant material occurred very rapidly (within 20 min) and this behavioural effect may be related to the efficacy of kaolin in controlling aphids under field conditions.


Asunto(s)
Áfidos/efectos de los fármacos , Conducta Animal/efectos de los fármacos , Caolín/farmacología , Animales , Áfidos/crecimiento & desarrollo , Áfidos/fisiología , Conducta de Elección , Control de Insectos , Ninfa/efectos de los fármacos , Ninfa/crecimiento & desarrollo , Ninfa/fisiología , Reproducción/efectos de los fármacos
12.
Ann Bot ; 98(1): 267-75, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16735404

RESUMEN

BACKGROUND AND AIMS: Kaolin applications have been used to mitigate the negative effects of water and heat stress on plant physiology and productivity with variable results, ranging from increased to decreased yields and photosynthetic rates. The mechanisms of action of kaolin applications are not clear: although the increased albedo reduces leaf temperature and the consequent heat stress, it also reduces the light available for photosynthesis, possibly offsetting benefits of lower temperature. The objective of this study was to investigate which of these effects are prevalent and under which conditions. METHODS: A 6% kaolin suspension was applied on well-irrigated and water-stressed walnut (Juglans regia) and almond (Prunus dulcis) trees. Water status (i.e. stem water potential, psi(s)), gas exchange (i.e. light-saturated CO2 assimilation rate, Amax; stomatal conductance, g(s)), leaf temperature (T(l)) and physiological relationships in treated and control trees were then measured and compared. KEY RESULTS: In both species, kaolin did not affect the daily course of psi(s) whereas it reduced Amax by 1-4 micromol CO2 m(-2) s(-1) throughout the day in all combinations of species and irrigation treatments. Kaolin did not reduce g(s) in any situation. Consequently, intercellular CO2 concentration (C(i)) was always greater in treated trees than in controls, suggesting that the reduction of Amax with kaolin was not due to stomatal limitations. Kaolin reduced leaf temperature (T(l)) by about 1-3 degrees C and leaf-to-air vapour pressure difference (VPD(l)) by about 0.1-0.7 kPa. Amax was lower at all values of g(s), T(l) and VPD(l) in kaolin-treated trees. Kaolin affected the photosynthetic response to the photosynthetically active radiation (PAR) in almond leaves: kaolin-coated leaves had similar dark respiration rates and light-saturated photosynthesis, but a higher light compensation point and lower apparent quantum yield, while the photosynthetic light-response curve saturated at higher PAR. When these parameters were used to model the photosynthetic response curve to PAR, it was estimated that the kaolin film allowed 63% of the incident PAR to reach the leaf. CONCLUSIONS: The main effect of kaolin application was the reduction, albeit minor, of photosynthesis, which appeared to be related to the shading of the leaves. The reduction in T(l) and VPD(l) with kaolin did not suffice to mitigate the adverse effects of heat and water stress on Amax.


Asunto(s)
Juglans/efectos de los fármacos , Caolín/farmacología , Prunus/efectos de los fármacos , Agua/metabolismo , Dióxido de Carbono/metabolismo , Deshidratación , Juglans/crecimiento & desarrollo , Juglans/metabolismo , Luz , Fotosíntesis/efectos de los fármacos , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/metabolismo , Tallos de la Planta/efectos de los fármacos , Tallos de la Planta/metabolismo , Prunus/crecimiento & desarrollo , Prunus/metabolismo , Temperatura
13.
J Inherit Metab Dis ; 29(1): 214-9, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16601897

RESUMEN

We report two unrelated boys with the X-linked creatine transporter defect (CRTR) and clinical features more severe than those previously described with this disorder. These two boys presented at ages 12 and 30 months with severe mental retardation, absent speech development, hypotonia, myopathy and extra-pyramidal movement disorder. One boy has seizures and some dysmorphic features; he also has evidence of an oxidative phosphorylation defect. They both had classical absence of creatine peak on brain magnetic resonance spectroscopy (MRS). In one, however, this critical finding was overlooked in the initial interpretation and was discovered upon subsequent review of the MRS. Molecular studies showed large genomic deletions of a large part of the 3' end of the complete open reading frame of the SLC6A8 gene. This report emphasizes the importance of MRS in evaluating neurological symptoms, broadens the phenotypic spectrum of CRTR and adds knowledge about the pathogenesis of creatine depletion in the brain and retina.


Asunto(s)
Cromosomas Humanos X , Proteínas de Transporte de Membrana/deficiencia , Proteínas de Transporte de Membrana/genética , Errores Innatos del Metabolismo/genética , Preescolar , Ojo/patología , Eliminación de Gen , Humanos , Lactante , Discapacidad Intelectual/diagnóstico , Discapacidad Intelectual/genética , Espectroscopía de Resonancia Magnética , Masculino , Errores Innatos del Metabolismo/diagnóstico , Proteínas del Tejido Nervioso/genética , Oxígeno/metabolismo , Fenotipo , Fosforilación , Proteínas de Transporte de Neurotransmisores en la Membrana Plasmática/genética
15.
Hum Mutat ; 18(6): 550-1, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11748859

RESUMEN

Mutations in CRX, a photoreceptor-specific transcription factor, can cause Leber congenital amaurosis (LCA), cone-rod dystrophy (CORD), and retinitis pigmentosa (RP), all of which feature severe visual impairment. Upon screening 55 patients with Leber congenital amaurosis, 75 patients with cone-rod dystrophy, 13 with cone dystrophy, and 36 with recessive or isolate RP for changes in the CRX sequence, we found two patients with Leber congenital amaurosis who carried heterozygously one of two novel frameshift mutations. The first mutation, Tyr191(1-bp del), was a de novo change and the second change, Pro263(1-bp del) was inherited from the proband's affected father. Both mutations are predicted to encode mutant versions of CRX with altered carboxy termini. We also found a previously reported missense mutation, Arg41Gln, heterozygously in a 47-year-old patient with a form of RP. The missense change Val242Met was found in an isolate case of CORD and no controls; however, its pathogenicity remains uncertain because only limited segregation analysis was possible. A nonpathogenic missense change, Ala158Thr, was found to be a variant present at relatively high frequency among African-Americans.


Asunto(s)
Mutación del Sistema de Lectura , Proteínas de Homeodominio/genética , Atrofia Óptica Hereditaria de Leber/genética , Transactivadores/genética , ADN/química , ADN/genética , Análisis Mutacional de ADN , Femenino , Genotipo , Humanos , Masculino
16.
Arch Ophthalmol ; 119(11): 1625-8, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11709012

RESUMEN

OBJECTIVES: To provide a description of refractive errors in healthy, term-born children, aged 1 through 48 months, and to test the hypotheses that spherical equivalent becomes significantly less hyperopic and less variable with increasing age. METHODS: Following a prospective, cross-sectional design, cycloplegic retinoscopy was used to measure the refractive error in both eyes of 514 healthy, term-born children in 12 age groups. Three hundred were aged 12 months or younger. Spherical equivalent and cylindrical power and axis were analyzed as a function of age. Prediction limits for spherical equivalent were calculated. RESULTS: Spherical equivalents of right and left eyes did not differ at any age. Hyperopia declined significantly with increasing age. The variability in spherical equivalent also decreased significantly with age. Cylindrical error of 1 diopter or more was found in 25% of the children; the proportion with astigmatism was highest in infancy and then waned. Myopia and anisometropia were rare, occurring in 3% and 1% of the sample, respectively. CONCLUSIONS: Significant declines in hyperopia and variability of spherical equivalent appear to be features of emmetropization. The normal prediction limits provide guidelines against which data from individual patients can be compared.


Asunto(s)
Ciclopentolato/administración & dosificación , Midriáticos/administración & dosificación , Pupila/efectos de los fármacos , Refracción Ocular , Errores de Refracción/epidemiología , Distribución por Edad , Preescolar , Estudios Transversales , Ojo/crecimiento & desarrollo , Femenino , Humanos , Lactante , Masculino , Massachusetts/epidemiología , Estudios Prospectivos , Valores de Referencia , Errores de Refracción/diagnóstico
17.
Int J Cancer ; 93(5): 681-6, 2001 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-11477578

RESUMEN

Elevated prostaglandin E(2) (PGE(2)) production is a common feature of human malignancies. This activity has often been attributed to increased metabolic activity of the cyclooxygenase enzymes, although a direct comparison of these 2 parameters i.e., prostaglandin production and cox protein expression, is rarely performed in the same malignant tissue. Using a murine model of metastatic breast cancer, we show that PGE(2) levels are positively correlated with increased tumorigenic and metastatic potential. Because prostaglandin synthesis is a product of 2 isoforms of the cyclooxygenase enzyme, we examined the expression and activity of both isoforms. All tumor cell lines examined, regardless of phenotype, express both cox-1 and cox-2 proteins in vitro. In contrast to the uniform cox-2 expression in vitro, only tumors resulting from the transplantation of metastatic cell lines express cox-2 in vivo. Cox-1 is detected in both metastatic and nonmetastatic tumors. Thus, this is the first evidence that, in the tumor milieu, cox-2 expression can be regulated differently in metastatic vs. nonmetastatic lesions. Examination of PGE(2) synthesis in vitro reveals that nearly complete inhibition of prostaglandin synthesis occurs in the presence of either indomethacin, which inhibits both isoforms, or NS398, which is selective for the cox-2 isoform. Thus, even though cell lines express both isoforms, the majority of the prostaglandin synthesis stems from the activity of the inducible, cox-2 isoform. Likewise, cell growth is inhibited by both indomethacin and NS398 in a dose-dependent manner, albeit at higher drug concentrations than required to ablate PGE(2) synthesis. Despite the inhibition of prostaglandin synthesis, the cox-2 enzyme levels (protein and mRNA) were increased by either indomethacin or NS398.


Asunto(s)
Neoplasias de la Mama/enzimología , Isoenzimas/biosíntesis , Prostaglandina-Endoperóxido Sintasas/biosíntesis , Animales , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Ciclooxigenasa 1 , Ciclooxigenasa 2 , Inhibidores de la Ciclooxigenasa 2 , Inhibidores de la Ciclooxigenasa/farmacología , Dinoprostona/metabolismo , Modelos Animales de Enfermedad , Femenino , Indometacina/farmacología , Isoenzimas/efectos de los fármacos , Proteínas de la Membrana , Ratones , Ratones Endogámicos BALB C , Metástasis de la Neoplasia , Trasplante de Neoplasias , Nitrobencenos/farmacología , Prostaglandina-Endoperóxido Sintasas/efectos de los fármacos , Sulfonamidas/farmacología , Células Tumorales Cultivadas
18.
Hum Mol Genet ; 10(8): 865-74, 2001 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-11285252

RESUMEN

Bardet-Biedl syndrome (BBS) is a genetically heterogeneous autosomal recessive disorder with the primary clinical features of obesity, pigmented retinopathy, polydactyly, hypogenitalism, mental retardation and renal anomalies. Associated features of the disorder include diabetes mellitus, hypertension and congenital heart disease. There are six known BBS loci, mapping to chromosomes 2, 3, 11, 15, 16 and 20. The BBS2 locus was initially mapped to an 18 cM interval on chromosome 16q21 with a large inbred Bedouin kindred. Further analysis of the Bedouin population allowed for the fine mapping of this locus to a 2 cM region distal to marker D16S408. Physical mapping and sequence analysis of this region resulted in the identification of a number of known genes and expressed sequence tag clusters. Mutation screening of a novel gene (BBS2) with a wide pattern of tissue expression revealed homozygous mutations in two inbred pedigrees, including the large Bedouin kindred used to initially identify the BBS2 locus. In addition, mutations were found in three of 18 unrelated BBS probands from small nuclear families.


Asunto(s)
Síndrome de Bardet-Biedl/genética , Cromosomas Humanos Par 16 , Secuencia Conservada , Secuencia de Aminoácidos , Animales , Mapeo Cromosómico , Clonación Molecular , Evolución Molecular , Femenino , Pruebas Genéticas , Humanos , Masculino , Ratones , Datos de Secuencia Molecular , Mutación , Linaje , Proteínas/genética , Ratas
19.
Arch Ophthalmol ; 119(4): 499-505, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11296015

RESUMEN

OBJECTIVE: To test the hypothesis that the more severe the acute phase retinopathy of prematurity (ROP) was in the preterm weeks, the more severely compromised is rod photoreceptor function after the ROP has resolved. METHODS: Electroretinographic (ERG) responses were recorded from 25 dark-adapted children (ages 2.5 months' postterm to 14 years) categorized by maximum, acute phase ROP (None to Very Severe). From the ERG a-wave "S," a sensitivity parameter for the rod photoreceptor response, and R(mp3), the saturated amplitude of the rod photoreceptor response were calculated using a model of the activation of rod phototransduction. The patients' results were compared with those of healthy controls (n = 71). RESULTS: Among those in the None, Mild, Moderate, and Severe categories, both S and R(mp3) varied significantly with severity of acute phase ROP. In the Very Severe category, ERG responses were too attenuated to calculate S and R(mp3). CONCLUSIONS: The rod photoreceptors must be involved in ROP. The more severe the acute phase ROP, the more severe is the compromise of the processes involved in the activation of phototransduction in the rods.


Asunto(s)
Células Fotorreceptoras Retinianas Bastones/fisiopatología , Retinopatía de la Prematuridad/fisiopatología , Enfermedad Aguda , Adolescente , Niño , Preescolar , Adaptación a la Oscuridad , Electrorretinografía , Edad Gestacional , Humanos , Lactante , Recién Nacido , Retinopatía de la Prematuridad/clasificación , Umbral Sensorial , Índice de Severidad de la Enfermedad , Agudeza Visual
20.
J Immunother ; 24(2): 138-43, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11265771

RESUMEN

Several laboratories have reported marked tumor inhibition when the cytokine interleukin-10 (IL-10) is overexpressed as a transgene in a variety of tumor cells. To identify critical effector molecules, we compared the expression of the chemokine crg-2, the murine homolog of human inducible protein 10 (human IP-10) in murine mammary tumors derived from the transplantation of six IL-10 expressing clones of tumor cell line 66.1, parental 66.1, or 66-neo-cells. We observed increased levels of IP-10 mRNA in all IL-10-expressing tumors examined in comparison to 66-neo. IP-10 mRNA was not detected in parental 66.1 tumors. The closely related chemokine Mig (monokine induced by interferon-gamma [IFN-gamma]) was also induced in all IL-10-expressing tumors. Studies of cultured tumor cells in vitro show that mammary epithelial tumor cells, in the absence of host elements, can express IP-10 and Mig in response to induction with either lipopolysaccharide (LPS) or IFN-gamma alone. The combination of LPS plus IFN-gamma resulted in even greater induction of IP-10 RNA. The kinetics of induction differ somewhat for the two chemokines, with IP-10 showing slower induction and less rapid decline. Because both Mig and IP-10 are chemotactic for tumor-infiltrating lymphocytes, we examined the presence of CD4+ and CD8+ lymphocytes in these tumors. Consistent with the upregulation of Mig and IP-10, we saw significantly increased numbers of CD8+ cells and a lesser increase in CD4+ cells in tumors with elevated levels of both chemokines.


Asunto(s)
Quimiocinas CXC/genética , Expresión Génica , Péptidos y Proteínas de Señalización Intercelular , Interleucina-10/genética , Animales , Northern Blotting , Linfocitos T CD4-Positivos/patología , Linfocitos T CD8-positivos/patología , Quimiocina CXCL10 , Quimiocina CXCL9 , Humanos , Inmunohistoquímica , Interferón gamma/farmacología , Cinética , Lipopolisacáridos/farmacología , Neoplasias Mamarias Experimentales/inmunología , Neoplasias Mamarias Experimentales/metabolismo , Ratones , Monocinas/genética , Trasplante de Neoplasias , ARN Mensajero/análisis , ARN Neoplásico/aislamiento & purificación , Transfección , Células Tumorales Cultivadas
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