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1.
Sci Total Environ ; 858(Pt 3): 159992, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36356748

RESUMEN

Bird migratory journeys are often long and hostile, requiring high energetic expenditure, and thus forcing birds to pause between migratory flights. Stopover sites allow migrants to replenish fuel reserves and rest, being crucial for the success of migration. Worldwide, the increasing accumulation of waste on landfills and rubbish dumps has been described to provide superabundant food resources for many bird species not only during the breeding and wintering seasons but also during migration, being used as stopover sites. Using GPS-tracking data of juvenile white storks (Ciconia ciconia) during their first migration from the Iberia Peninsula to the sub-Saharan wintering grounds, we uncover the effects of stopping en route on individual migratory performance. Particularly, we examine the benefits of stopping at artificial sites (landfills and rubbish dumps) when compared to natural stopover sites (wetlands, agricultural or desert areas) and explore the influence of anthropogenic food resources on storks' migratory strategies. Overall, white storks spent up to one-third of the migration in stopovers. We found that birds that stopped for longer periods made more detours, increasing migration duration by half a day for each stopover day. Stopping more often did not reflect on increasing in-flight energetic efficiency nor the likelihood of completing the migration. Juvenile storks used artificial sites in 80 % of the stopover days, spending 45 % less time and 10 % less energy foraging than when using natural stopovers. While stopping in landfills did not translate into differences in migratory performance, individuals in poor body condition possibly rely on these sites to improve body weight before proceeding, enabling them to successfully complete migration. Artificial stopover sites are attractive and likely increase the number and duration of stops for white storks. Even though the consequences of arriving late at the wintering grounds are unknown, it can lead to cascading consequences, influencing individual fitness and population dynamics.


Asunto(s)
Migración Animal , Ejercicio Físico , Humanos , África del Norte
2.
Genet Mol Res ; 13(3): 8014-24, 2014 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-25299116

RESUMEN

Guarana has great agricultural potential and is largely used therapeutically and in the production of non-alcoholic energy drinks. Genomic and proteomic studies are crucial to identify proteins that play central roles in the maintenance and viability of fruits, as well as to identify proteins related to the main metabolic pathways. However, the success of any protein analysis starts with the protein extract preparation, which needs to offer an extract that is free of contaminants. This study aimed to evaluate different extraction methods to obtain high-quantity and high-quality extracts that are compatible with analysis by 2-dimensional electrophoresis and tandem mass spectrometry protein identification. Three different methods were tested: trichloroacetic acid (TCA)/acetone, sodium dodecyl sulfate (SDS)/phenol, and polyvinylpolypyrrolidone (PVPP)/SDS/phenol. The extract obtained from the TCA/acetone precipitation presented low solubility and contamination with lipids and carbohydrates. On the other hand, the quality of the extract gradually improved after using phenol and PVPP/phenol, enabling a yield up to 2 mg/g macerated tissues and the detection of 457 spots by 2-dimensional electrophoresis. The effectiveness of the procedure used was validated by identification of 10 randomly selected proteins by mass spectrometry. The procedure described here can be a starting point for applications using tissues of other organs of guarana or tissues of species that are similar to guarana.


Asunto(s)
Paullinia/química , Proteínas de Plantas/metabolismo , Proteómica , Electroforesis en Gel Bidimensional , Espectrometría de Masa por Ionización de Electrospray , Espectrometría de Masas en Tándem
3.
Poult Sci ; 91(3): 758-64, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22334753

RESUMEN

During the first week of the posthatching period, before the immune system is mature enough to produce its own B lymphocytes, a chick's humoral immunity depends on maternal antibodies (IgY) received from the egg yolk. During incubation and after hatching, the yolk sac (YS) membrane transfers nutrients (including IgY) from the egg yolk to the developing embryo or newly hatched chick. The objective of this study was to determine the effects of breeder flock age on the total IgY content of egg yolks and chick YS from a commercial broiler breeder strain. Hatching eggs from the same broiler breeder flock were collected at 32, 40, and 55 wk of age. One group of eggs per flock age was used to determine the egg yolk total IgY content. Another group of eggs was incubated for 21.5 d, and upon hatching, the YS of newly hatched chicks were collected to determine the total IgY content. Egg and egg yolk weight increased with flock age, but YS weights did not reflect egg yolk weight. The total IgY content per gram of egg yolk increased with flock age; this fact plus the observed yolk weight increase with flock age notably increased the total IgY contained in yolks of eggs laid by 55-wk-old breeders. However, chicks hatching from 55-wk-old breeders had less IgY per gram of YS than chicks from 32- and 40-wk-old breeders. Whether there are differences in the rates of YS absorption between chicks of different breeder ages is unknown. This research provided total IgY values for broiler breeder egg yolk and chick YS of a commonly used meat-type chicken strain. Differences in egg yolk and YS total IgY contents due to flock age in this type of bird had not been previously reported. Research on the physiological consequences of YS absorption rates in chicks from different breeder ages is advised.


Asunto(s)
Embrión de Pollo/inmunología , Yema de Huevo/inmunología , Inmunoglobulinas/análisis , Saco Vitelino/inmunología , Factores de Edad , Animales
4.
Poult Sci ; 89(12): 2735-42, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21076114

RESUMEN

The objective of this study was to determine the effects of flock age and egg weight on hatching egg characteristics, fertility, hatchability, salable chick production, and broiler performance using a commercial Cobb 500 broiler breeder flock. Hatching eggs from the same breeder flock in 3 weight categories (light, average, and heavy) were obtained from a commercial hatchery when the birds were 29 and 59 wk of age. One group of eggs per age and weight category was selected to assess specific gravity and was broken open to weigh egg components. Another group of eggs was incubated for 21.5 d and incubation parameters were measured. At hatching, all salable chicks were individually weighed and placed in floor pens, where they were grown out for 41 d. Daily mortality, weekly feed consumption, and individual BW at 21 and 41 d were recorded. Irrespective of flock age and egg weight, all eggs had a specific gravity lower than 1.080, the commercial set value. Eggs from the young flock age had a smaller proportion of yolk and a greater proportion of albumen. Age affected fertility, with a lower value observed at 29 wk of age. Chicks from the flock at 59 wk hatched earlier than chicks from the flock at 29 wk, and light eggs hatched earlier than both average and heavy eggs. Broilers from the 29-wk-old breeders had a lower final BW than broilers from the 59-wk-old breeders. The smaller proportion of yolk in eggs from 29-wk-old broiler breeders may be associated with the low final BW observed in their offspring. This could mean that chicks hatching from young broiler breeders, which produce eggs with small yolks, may be at a disadvantage when reared under the same conditions as chicks produced by older broiler breeders whose eggs have larger yolks.


Asunto(s)
Alimentación Animal , Pollos/crecimiento & desarrollo , Óvulo/crecimiento & desarrollo , Animales , Peso Corporal/genética , Cruzamiento/métodos , Embrión de Pollo/crecimiento & desarrollo , Pollos/genética , Costos y Análisis de Costo , Femenino , Fertilidad , Carne/economía , Carne/normas , Tamaño de los Órganos
5.
Caries Res ; 44(1): 60-8, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20130402

RESUMEN

The aim of this study was to examine the relationship between total daily fluoride intake (TDFI), daily urinary fluoride excretion (DUFE) and fractional fluoride retention (FFR) using available data, in order to clarify the ability of DUFE to predict TDFI and, therefore, the risk of fluorosis development. Examination of published reports of simultaneous measurement of TDFI and DUFE, together with data from two unpublished Chilean studies, yielded data for 212 children aged less than 7 years and for 283 adults aged 18-75 years, providing a total of 212 and 269 data points, respectively. The relationship between DUFE and TDFI was studied for children and adults, separately. Daily fluoride retention (DFR) was estimated as a function of TDFI in children and adults assuming an average 90% fluoride absorption, and the numerical relationships between the estimated FFR and the TDFI were explored. Limiting FFR values of 0.55 and 0.36 were found for children and adults, respectively, above a threshold of TDFI of 0.5 and 2 mg, respectively. Neutral fluoride balances were predicted when the TDFI was equal to approximately 0.07 mg F/day for children and 0.8 mg F/day for adults. For children and adults, it is possible to obtain reasonably good estimations of community-based TDFI and DFR, using DUFE data. The advantages and limitations of these relationships, together with the need for future studies, are discussed.


Asunto(s)
Cariostáticos/administración & dosificación , Fluoruros/administración & dosificación , Absorción , Adolescente , Adulto , Anciano , Algoritmos , Cariostáticos/análisis , Cariostáticos/farmacocinética , Niño , Preescolar , Femenino , Fluoruros/farmacocinética , Fluoruros/orina , Fluorosis Dental/etiología , Predicción , Humanos , Lactante , Masculino , Persona de Mediana Edad , Adulto Joven
6.
Poult Sci ; 89(1): 82-7, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20008805

RESUMEN

By the time of hatching, the residual yolk sac (RYS) should be completely internalized into the body cavity of the chick via the navel and the navel should be closed (healed). After hatching, the RYS contents are used for general growth and development including growth of the small intestine. This research examined the relationship between the presence of navel buttons (an unhealed navel covered with a scab) and the RYS weight and intestinal villi height of broiler chicks from 0 to 5 d posthatching. Hatching eggs containing live embryos were collected at 18, 19, and 20 d of incubation (n = 5/d). At 21 d of incubation, chicks with healed navels (H) and chicks with navel buttons smaller than 3 mm in diameter (B) were obtained (n = 30/group). The BW and RYS of embryos (n = 5/d) and chicks (n = 5/treatment per day) were weighed. Samples of the small intestine (duodenum and ileum) were processed for histological evaluation to measure villi height. The trial was replicated in time 4 wk after the first collection using eggs and chicks from the same flock. Data were analyzed using SAS PROC MIXED (P < or = 0.05). No significant differences in BW were observed between H and B chicks. Average RYS weight and percentage RYS were greater in B than in H chicks. The interaction of age and navel condition significantly influenced both duodenal and ileal villi heights. On most of the days, duodenal and ileal villi were shorter in B than in H chicks. The presence of small navel buttons at hatching is indicative of impaired absorption of the RYS content and decreased intestinal villi growth. Further research on the relationship between navel buttons, intestinal physiology, and yolk sac infections is advised.


Asunto(s)
Pollos/anomalías , Intestinos/anatomía & histología , Intestinos/crecimiento & desarrollo , Animales , Saco Vitelino
7.
Acta Trop ; 107(2): 168-73, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18603222

RESUMEN

Parasites of wild primates are important for conservation biology and human health due to their high potential to infect humans. In the Amazon region, non-human primates are commonly infected by Trypanosoma cruzi and T. rangeli, which are also infective to man and several mammals. This is the first survey of trypanosomiasis in a critically endangered species of tamarin, Saguinus bicolor (Callitrichidae), from the Brazilian Amazon Rainforest. Of the 96 free-ranging specimens of S. bicolor examined 45 (46.8%) yielded blood smears positive for trypanosomes. T. rangeli was detected in blood smears of 38 monkeys (39.6%) whereas T. cruzi was never detected. Seven animals (7.3%) presented trypanosomes of the subgenus Megatrypanum. Hemocultures detected 84 positive tamarins (87.5%). Seventy-two of 84 (85.7%) were morphologically diagnosed as T. rangeli and 3 (3.1%) as T. cruzi. Nine tamarins (9.4%) yielded mixed cultures of these two species, which after successive passages generated six cultures exclusively of T. cruzi and two of T. rangeli, with only one culture remaining mixed. Of the 72 cultures positive for T. rangeli, 62 remained as established cultures and were genotyped: 8 were assigned to phylogenetic lineage A (12.9%) and 54 to lineage B (87.1%). Ten established cultures of T. cruzi were genotyped as TCI lineage (100%). Transmission of both trypanosome species, their potential risk to this endangered species and the role of wild primates as reservoirs for trypanosomes infective to humans are discussed.


Asunto(s)
Animales Salvajes/parasitología , Conservación de los Recursos Naturales , Enfermedades de los Monos , Saguinus/parasitología , Trypanosoma cruzi , Trypanosoma , Tripanosomiasis/veterinaria , Animales , Brasil/epidemiología , Enfermedad de Chagas/parasitología , Enfermedad de Chagas/veterinaria , Genotipo , Enfermedades de los Monos/epidemiología , Enfermedades de los Monos/parasitología , Reacción en Cadena de la Polimerasa/métodos , Prevalencia , Árboles , Trypanosoma/clasificación , Trypanosoma/genética , Trypanosoma/aislamiento & purificación , Trypanosoma/patogenicidad , Trypanosoma cruzi/clasificación , Trypanosoma cruzi/genética , Trypanosoma cruzi/aislamiento & purificación , Trypanosoma cruzi/patogenicidad , Tripanosomiasis/epidemiología , Tripanosomiasis/parasitología
8.
Gastroenterol Hepatol ; 27(8): 464-6, 2004 Oct.
Artículo en Español | MEDLINE | ID: mdl-15388050

RESUMEN

Primary hepatic actinomycosis is a rare infection that can clinically be confused with hepatic pyogenous abscesses or neoproliferative processes. We present the case of a 71-year-old man who had previously undergone total gastrectomy for gastric adenocarcinoma. After 4 years of favorable clinical course he presented a space-occupying lesion in the right hepatic lobe. Diagnostic tests were nonspecific and the diagnosis was confirmed by histological study of a biopsy of the lesion obtained through laparotomy. Prolonged antibiotic treatment produced a complete response. The etiopathogenesis and diagnostic-therapeutic options of hepatic actinomycosis are reviewed.


Asunto(s)
Actinomicosis/microbiología , Absceso Hepático/microbiología , Actinomicosis/diagnóstico por imagen , Actinomicosis/tratamiento farmacológico , Actinomicosis/patología , Anciano , Antibacterianos/uso terapéutico , Biopsia con Aguja , Diagnóstico Diferencial , Humanos , Hígado/diagnóstico por imagen , Hígado/microbiología , Hígado/patología , Absceso Hepático/diagnóstico por imagen , Absceso Hepático/tratamiento farmacológico , Absceso Hepático/patología , Masculino , Penicilina G/uso terapéutico , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
9.
Int Dent J ; 54(2): 73-6, 2004 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15119796

RESUMEN

AIMS: To identify the prevalence and different degrees of periodontal disease in an isolated community (Isla Grande, Colombia) with no dental services and low educational level with the use of CPITN, and to establish periodontal treatment needs in different age groups. RESULTS: Of 116 people examined, 0.9% were in periodontal health (CPITN value 0), 18.1% had gingival bleeding (CPITN value 1), 51.7% had supra or subgingival calculus (CPITN value 2), 18.1% presented pockets 3.5-5.0 mm deep (CPITN value 3), and 11.2% had pathological pockets of 5.5mm or deeper (CPITN value 4). No clear differences were observed between sexes. CONCLUSIONS: This study shows that 81% of the sample has some type of periodontal treatment need, with 69.8% of them requiring periodontal treatment that may be supplied by a hygienist and 11.2% requiring specialised treatment. Implementation of oral health education and oral prevention programmes was recommended to the authorities for this community.


Asunto(s)
Evaluación de Necesidades/estadística & datos numéricos , Enfermedades Periodontales/epidemiología , Adolescente , Adulto , Factores de Edad , Anciano , Niño , Colombia/epidemiología , Cálculos Dentales/epidemiología , Femenino , Hemorragia Gingival/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Bolsa Periodontal/epidemiología , Grupos de Población/estadística & datos numéricos , Prevalencia
10.
Nucleosides Nucleotides Nucleic Acids ; 19(8): 1281-8, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11097058

RESUMEN

A new amphiphilic, high-molecular weight poly (N-acryloylmorpholine) (PAcM) polymer has been used to be linked to oligonucleotide chains through a liquid-phase stepwise synthesis. This new conjugate has been investigated for its melting property, nuclease stability and capacity to elicit RNase H activity. Its antisense activity against an HIV-1 target has been also evaluated.


Asunto(s)
Morfolinas/farmacología , Oligonucleótidos Antisentido/farmacología , Ribonucleasa H/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Glucósidos , Inosina/análogos & derivados , Estructura Molecular , Peso Molecular , Morfolinas/síntesis química , Morfolinas/química , Desnaturalización de Ácido Nucleico , Oligonucleótidos Antisentido/síntesis química , Oligonucleótidos Antisentido/química , Polietilenglicoles/química , Solubilidad
11.
J Biol Chem ; 275(39): 30701-6, 2000 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-10900200

RESUMEN

P2Y ATP receptors are widely expressed in mammalian tissues and regulate a broad range of activities. Multiple subtypes of P2Y receptors have been identified and are distinguished both on a molecular basis and by pharmacologic substrate preference. Functional evidence suggests that hepatocytes from the little skate Raja erinacea express a primitive P2Y ATP receptor lacking pharmacologic selectivity, so we cloned and characterized this receptor. Skate hepatocyte cDNA was amplified with degenerate oligonucleotide probes designed to identify known P2Y subtypes. A single polymerase chain reaction product was found and used to screen a skate liver cDNA library. A 2314-base pair cDNA clone was generated that contained a 1074-base pair open reading frame encoding a 357-amino acid gene product with 61-64% similarity to P2Y(1) receptors and 21-37% similarity to other P2Y receptor subtypes. Pharmacology of the putative P2Y receptor was examined using the Xenopus oocyte expression system and revealed activation by a range of nucleotides. The receptor was expressed widely in skate tissue and was expressed to a similar extent in other primitive organisms. Phylogenetic analysis suggested that this receptor is closely related to a common ancestor of the P2Y subtypes found in mammals, avians, and amphibians. Thus, the skate liver P2Y receptor functions as a primitive P2Y ATP receptor with broad pharmacologic selectivity and is related to the evolutionary forerunner of P2Y(1) receptors of higher organisms. This novel receptor should provide an effective comparative model for P2Y receptor pharmacology and may improve our understanding of nucleotide specificity among the family of P2Y ATP receptors.


Asunto(s)
Receptores Purinérgicos P2/genética , Rajidae/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Clonación Molecular , Evolución Molecular , Hígado/química , Datos de Secuencia Molecular , Nucleótidos/metabolismo , Filogenia , Receptores Purinérgicos P2/clasificación , Receptores Purinérgicos P2/aislamiento & purificación , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , Especificidad por Sustrato
12.
Mem Inst Oswaldo Cruz ; 95(2): 189-91, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10733737

RESUMEN

A comparison of kDNA restriction-endonuclease fragment patterns from strains representing selected Endotrypanum zymodemes was done by schizodeme analysis. As the degree of heterogeneity within mini-circles varied among species or strains of Endotrypanum, the fingerprint obtained with each of the restriction enzymes was unique for each of these parasites. The data have revealed that this trypanosomatid genus is much more complex than it was originally thought to be.


Asunto(s)
ADN de Cinetoplasto/análisis , Trypanosomatina/clasificación , Animales , Heterogeneidad Genética , Variación Genética/genética , Isoenzimas/genética , Leishmania/clasificación , Leishmania/enzimología , Leishmania/genética , Polimorfismo Genético/genética , Trypanosomatina/enzimología , Trypanosomatina/genética
13.
Mem Inst Oswaldo Cruz ; 94(2): 261-8, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10224540

RESUMEN

This article reviews current concepts of the biology of Endotrypanum spp. Data summarized here on parasite classification and taxonomic divergence found among these haemoflagellates come from our studies of molecular characterization of Endotrypanum stocks (representing an heterogenous population of reference strains and isolates from the Brazilian Amazon region) and from scientific literature. Using numerical zymotaxonomy we have demonstrated genetic diversity among these parasites. The molecular trees obtained revealed that there are, at least, three groups (distinct species?) of Endotrypanum, which are distributed in Central and South America. In concordance with this classification of the parasites there are further newer molecular data obtained using distinct markers. Moreover, comparative studies (based on the molecular genetics of the organisms) have shown the phylogenetic relationships between some Endotrypanum and related kinetoplastid lineages.


Asunto(s)
Perezosos/parasitología , Trypanosomatina/clasificación , Trypanosomatina/aislamiento & purificación , Animales , Anticuerpos Antiprotozoarios/análisis , ADN Protozoario/análisis , Trypanosomatina/genética , Trypanosomatina/inmunología
14.
J Med Entomol ; 34(2): 189-92, 1997 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9103762

RESUMEN

The developmental biology (parasite establishment, migration, and differentiation) of Brazilian strains of Endotrypanum are reported for 3 sand fly species: Lutzomyia longipalpis Lutz & Neiva, L. shannoni Dyar, and Phlebotomus papatasi Scopoli. Laboratory-reared sand flies were infected by feeding on a promastigote suspension through a chick-skin membrane. Infections within the insect gut were examined at various times after feeding by staining fresh and fixed specimens. Development of Endotrypanum varied for each parasite-host species association. After feeding on culture forms of E. schaudinni Mesnil & Brimont (strain ISHA/BR/80/IM1111), significantly more L. shannoni (100%, 9/9) became infected than did L. longipalpis (62.3%, 33/53) or P. papatasi (27.3%, 15/55). The greatest number of infections were in the midgut and hindgut from 6 to 16 d after feeding, but flagellates also were present in the Malpighian tubules. Moreover, distinct development patterns in the sand fly gut were obtained when the Callejon L. longipalpis colony was fed on cultures of other Endotrypanum strains. Significantly fewer sand flies became infected with strain MCHO/BR/85/IM2259 (18.2%, 4/22) than with strain ISHA/BR/80/IM1111 (55.6%, 20/36). There were also individual variation in the distribution and survival of parasites within the guts of flies in each group. These data indicate that there is variation in the susceptibility to infection with Endotrypanum among and within sand fly species.


Asunto(s)
Psychodidae/parasitología , Trypanosomatina/crecimiento & desarrollo , Animales
16.
Parasitology ; 113 ( Pt 1): 39-48, 1996 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8710413

RESUMEN

In this study, we have analysed enzyme polymorphism among a group of protozoan parasites of the genus Endotrypanum (Kinetoplastida: Trypanosomatidae). Seventeen stocks of Endotrypanum spp. isolated from sloths (Choloepus didactylus and C. juruanus) in the Amazon Region of Brazil were analysed by enzyme electrophoresis, and their electromorphic profiles were compared with reference strains reported previously. The 16 enzymic loci were analysed, and the strains were classified into zymodemes, each representing parasites with unique enzyme profiles. Each zymodeme was considered as an elementary taxon, and using numerical analyses (cladistic, agglomerative hierarchical and ordination techniques) the genus was shown to be monophyletic and the 12 zymodemes characterized could be divided into 3 groups (A, B, C). The heterogeneous population (which may represent a complex of parasite species or strains variants) showed, however, no correlation with the origin (i.e. host species involved or geographic area of isolation) of Endotrypanum stocks. Eight isolates of Endotrypanum sp. from Rondônia State (Brazil) and a parasite strain from Panama were clustered together into a zymodeme, which was phenetically closely related to the E. monterogeii from Costa Rica. The data indicate that E. schaudinni is a species complex.


Asunto(s)
Isoenzimas/genética , Polimorfismo Genético , Trypanosomatina/genética , Animales , Brasil , Análisis por Conglomerados , Electroforesis en Gel de Agar , Frecuencia de los Genes , Isoenzimas/análisis , Fenotipo , Filogenia , Perezosos , Programas Informáticos , Trypanosomatina/clasificación , Trypanosomatina/enzimología
17.
J Am Optom Assoc ; 67(5): 283-7, 1996 May.
Artículo en Inglés | MEDLINE | ID: mdl-8888847

RESUMEN

BACKGROUND: A 5-year-old Hispanic male with an ocular history of retinopathy of prematurity was seen for an evaluation of his functional abilities and a determination of the possible treatment options for rehabilitation. The greatest concern was to provide the boy with the tools necessary to ensure success in the educational system. METHODS: A low-vision evaluation was performed and baseline information was obtained, including distance visual acuities, near visual acuities, visual fields and refractive error. This data was then used to determine if, in a classroom setting, the child would encounter any difficulties that could benefit from assistive optical devices or modifications of environment. RESULTS: The child demonstrated a large angle of head turn in order to eccentrically view to obtain his best visual acuity. His refractive error had no effect on this visual acuity at distance. Visual acuities taken at near demonstrated a working distance of 4 cm with preference to using the right eye. A gross confrontation field suggested a relatively full field in the right eye, but a temporal field loss in the left eye. CONCLUSIONS: A monocular bifocal system was prescribed for use in the classroom and at home when studying. The bifocal segment was a round +24 diopter aspheric lens, 22 mm in diameter, which was reshaped into a flat-top and adhered to a carrier lens. The carrier lens was ordered with 10 prism diopters base left in each eye. This system addressed both the large eccentric viewing position and the magnification necessary to alleviate the accommodative system.


Asunto(s)
Anteojos , Baja Visión/terapia , Preescolar , Humanos , Recién Nacido , Masculino , Retinopatía de la Prematuridad/complicaciones , Retinopatía de la Prematuridad/fisiopatología , Baja Visión/etiología , Baja Visión/fisiopatología , Agudeza Visual
18.
Eur J Biochem ; 225(1): 333-9, 1994 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-7925453

RESUMEN

The expression of trans-sialidase and sialidase activities in the kinetoplastid protozoa was explored as a potential marker to discriminate between the morphologically indistinguishable flagellates isolated from human, insects and vertebrate reservoir hosts. By virtue of the differences observed in the ratios of these enzyme activities, a collection of 52 species and strains comprising the major taxa of these parasites could be separated into four expression types. Type-I parasites express comparable levels of both trans-sialidase and sialidase activities (Endotrypanum species and Trypanosoma lewisi). Type-II parasites express predominantly trans-sialidase activity (Trypanosoma cruzi and Trypanosoma conorhini). Type-III parasites express sialidase activity exclusively (Trypanosoma rangeli and Trypanosoma leeuwenhoeki). Type-IV parasites do not express either activity (Leishmania species and Trypanoplasma borreli). The measurement of trans-sialidase and sialidase activities thus permits the differentiation of parasites frequently found in the same insect vectors that are difficult to distinguish, such as T. cruzi and T. rangeli, or in the same sylvatic vertebrate and invertebrate hosts, such as Leishmania and Endotrypanum.


Asunto(s)
Neuraminidasa/análisis , Sialiltransferasas/análisis , Trypanosoma/clasificación , Trypanosoma/enzimología , Trypanosomatina/clasificación , Animales , ADN Protozoario/aislamiento & purificación , Reservorios de Enfermedades , Humanos , Insectos , Neuraminidasa/biosíntesis , Reacción en Cadena de la Polimerasa , Sialiltransferasas/biosíntesis , Trypanosoma/aislamiento & purificación , Trypanosomatina/enzimología , Trypanosomatina/aislamiento & purificación , Vertebrados
20.
G E N ; 44(3): 227-32, 1990.
Artículo en Español | MEDLINE | ID: mdl-2152312

RESUMEN

This paper reports a case of an histological non aggressive thymoma with myasthenic symptoms as the first clinical manifestation. Three years after its complete surgical resection liver metastases appeared without evidence of intrathoracic neoplastic disease. The extrathoracic metastases are uncommon and the thymomatous myasthenia gravis is present in 25 to 50% of cases. We reviewed the literature and analyzed its clinical pathological characteristics and therapeutics approach.


Asunto(s)
Neoplasias Hepáticas/secundario , Miastenia Gravis/etiología , Timoma/complicaciones , Neoplasias del Timo/complicaciones , Humanos , Neoplasias Hepáticas/diagnóstico por imagen , Masculino , Mediastino/diagnóstico por imagen , Persona de Mediana Edad , Timoma/diagnóstico por imagen , Timoma/patología , Timoma/cirugía , Neoplasias del Timo/diagnóstico por imagen , Neoplasias del Timo/patología , Neoplasias del Timo/cirugía , Tomografía Computarizada por Rayos X , Ultrasonografía
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