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1.
Trop Biomed ; 33(1): 88-94, 2016 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33579145

RESUMEN

Seroprevalence of human toxocariasis was studied, based on 1544 samples selected from a total of 3524 submitted to the University of the West Indies in Kingston, Jamaica for diagnosis of dengue during an epidemic in 2010. The prevalence of anti-Toxocara IgG using the CELISA® (Cellabs) ELISA was 21.2% and males (24.4%) were significantly more likely to be exposed than females (17.5%) [χ2 =10.4; p=0.001]. No association was foundbetween exposure to Toxocara and area of residence (rural vs. urban) [χ2 =0.835; p = 0.409]. Prevalence of infection peaked in adolescents (10-19 years-old) and declined thereafter although a rise in prevalence was seen in older age classes. There was a high prevalence of toxocariasis in Jamaica with significant exposure among school age children with no predilection to either sex. The study will inform future work on elucidating the public health and clinical significance of toxocariasis in Jamaica.

2.
West Indian Med J ; 64(2): 87-91, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26360679

RESUMEN

OBJECTIVE: Aminoglycosides were introduced into use over 60 years ago. The University Hospital of the West Indies (UHWI), a tertiary care teaching hospital, in Kingston, Jamaica, introduced the use of gentamicin in 1973 and amikacin in 1980. This report examined the susceptibility patterns to these agents in 1547 consecutive isolates of Gram negative bacilli (GNB) encountered between September 1 and November 30, 2011, at UHWI and compares the data with those observed previously in 1981 at the same institution. METHODS: The Vitek 2 (bioMeriéux, Durham, NC) was used for isolate identification, minimum inhibitory concentration determination and aminoglycoside susceptibility testing. Quality control was done using American Type Culture Collection standard strains of E coli (ATCC 25922) and Pseudomonas aeruginosa (ATCC 27853). RESULTS: Of the 1547 organisms, 267 had resistance to one or both aminoglycosides. Amikacin resistance increased from 0.6% (1981) to 7.2% [2011] (p < 0.05), while gentamicin resistance increased from 6.7% to 14.8% (p < 0.05) for the corresponding period. The majority of samples with aminoglycoside resistant organisms came from the intensive care unit and surgical inpatients. Urine samples persistently produced the largest amount of gentamicin resistant isolates. CONCLUSIONS: Although there has been a statistically significant rise in aminoglycoside resistance, aminoglycosides continue to remain highly effective against approximately 83% of GNB despite continuous usage at this institution for over three decades. Continued national surveillance, implementation of infection control policies and antibiotic stewardship are all essential in retaining low resistance levels.

3.
J Pediatr ; 165(3): 637, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24948342
4.
J Parasitol ; 90(2): 301-7, 2004 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15165052

RESUMEN

Naiadocystis phykoterion n. gen., n. sp. (Apicomplexa: Eugregarinida: Hirmocystidae), is described from the Mexican pygmy grasshopper, Paratettix mexicanus (Orthoptera: Tetrigidae), collected from sandbars along Harmon Creek, Walker County, Texas, in the western edge of the Texas Big Thicket. Naiadocystis n. gen. is distinguished by the form of the epimerite complex, a simple cordoid or toroid epimerite with an interior obconoid structure resembling a funnel that tapers to a distinct axial canal bisecting the protomerite, which is conspicuous in all stages of development, and a satellite protomerite reduced to a linearly crateriform cup or sucker that receives and enfolds posterior end of primite deutomerite. Association is precocious, caudofrontal, and biassociative. Gametocysts are spherical. Sporoducts are present but vestigial and irregular in number. Oocysts are broadly elliptoid with 4 small spherical polar knobs, 1 each at 30 degrees, 150 degrees, 210 degrees, and 330 degrees, and dehisce en masse. The species described herein are differentiated by their overall size and relative proportion of cellular structures. Naiadocystis acantholobae (Hoshide, 1952) n. comb., Naiadocystis acrydiinarum (Semans, 1939) n. comb., and Naiadocystis tetrigis (Corbel, 1968) n. comb. are recognized as members of Naiadocystis previously placed within Gregarina (Apicomplexa: Eugregarinida: Gregarinidae).


Asunto(s)
Apicomplexa/clasificación , Saltamontes/parasitología , Animales , Apicomplexa/aislamiento & purificación , Apicomplexa/ultraestructura , Texas
5.
Mol Biol Evol ; 18(9): 1708-19, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11504851

RESUMEN

We investigated the relationship between satellite copy number and chromosomal evolution in tuco-tucos (genus Ctenomys), a karyotypically diverse clade of rodents. To explore phylogenetic relationships among 23 species and 5 undescribed forms, we sequenced the complete mitochondrial cytochrome b genes of 27 specimens and incorporated 27 previously published sequences. We then used quantitative dot-blot techniques to assess changes in the copy number of the major Ctenomys satellite DNA (satDNA), named RPCS. Our analysis of the relationship between variation in copy number of RPCS and chromosomal changes employed a maximum-likelihood approach to infer the copy number of the satellite RPCS in the ancestors of each clade. We found that amplifications and deletions of RPCS were associated with extensive chromosomal rearrangements even among closely related species. In contrast, RPCS copy number stability was observed within clades characterized by chromosomal stability. This example reinforces the suspected role of amplification, deletion, and intragenomic movement of satDNA in promoting extensive chromosomal evolution.


Asunto(s)
Cromosomas/genética , ADN Satélite/genética , Roedores/genética , Animales , Aberraciones Cromosómicas , Grupo Citocromo b/genética , ADN/química , ADN/genética , ADN Mitocondrial/química , ADN Mitocondrial/genética , Evolución Molecular , Amplificación de Genes , Eliminación de Gen , Dosificación de Gen , Datos de Secuencia Molecular , Filogenia , Roedores/clasificación , Análisis de Secuencia de ADN , Especificidad de la Especie
6.
Am J Clin Nutr ; 72(5): 1191-5, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11063448

RESUMEN

BACKGROUND: The serum transferrin receptor (TfR) and the ratio of TfR to serum ferritin (TfR:SF) have been shown to be useful as early indicators of iron deficiency. OBJECTIVE: The objective of this study was to evaluate the performance of TfR and TfR:SF in the assessment of iron deficiency in infants and to analyze age-related changes in both variables. DESIGN: A total of 716 blood samples obtained from 515 healthy infants aged 8-15 mo were studied. RESULTS: In 144 samples in which all other laboratory indicators of iron status were within the reference range, the median and 95% CI for TfR and TfR:SF were 8.5 mg/L (95% CI: 5.9, 13.5) and 497 (95% CI: 134, 975), respectively. TfR and TfR:SF were significantly correlated with the other laboratory indicators of iron status. Furthermore, as the severity of iron deficiency progressed, there was a gradual increase in mean TfR concentration (P: < 0.00001; analysis of variance). The sensitivity of TfR > 13.5 mg/L and TfR:SF > 975 in the diagnosis of iron deficiency was 23.6% and 68.4%, respectively. The specificity was 98.3% and 63.3% for TfR and TfR:SF, respectively. The sensitivity and specificity of SF < 10 microg/L were 63.7% and 60.8%, respectively. Receiver operator characteristic analysis showed that TfR and TfR:SF were more accurate than was SF alone in the diagnosis of iron deficiency. CONCLUSIONS: TfR and TfR:SF showed age-related changes; TfR and TfR:SF appear to be better diagnostic tests for iron deficiency in infants than SF.


Asunto(s)
Ferritinas/sangre , Deficiencias de Hierro , Receptores de Transferrina/sangre , Envejecimiento , Recuento de Eritrocitos , Índices de Eritrocitos , Femenino , Hemoglobinas/análisis , Humanos , Lactante , Masculino , Curva ROC , Valores de Referencia , Sensibilidad y Especificidad
7.
Am J Public Health ; 90(10): 1629-33, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11030002

RESUMEN

OBJECTIVES: This study determined the prevalence of food insecurity and hunger in low-income legal immigrants. METHODS: We conducted a cross-sectional survey of Latino and Asian legal immigrants attending urban clinics and community centers in California, Texas, and Illinois with a food security questionnaire. RESULTS: Among 630 respondents, 40% of the households were food insecure without hunger and 41% were food insecure with hunger. Independent predictors of hunger were income below federal poverty level (odds ratio [OR] = 2.72, 95% confidence interval [CI] = 1.72, 4.30), receipt of food stamps (OR = 2.53, 95% CI = 1.57, 4.09), Latino ethnicity (OR = 2.39, 95% CI = 1.49, 3.82), and poor English (OR = 1.76, 95% CI = 1.10, 2.82). CONCLUSIONS: The prevalence of hunger among low-income legal immigrants is unacceptably high. Access to food assistance programs is important for the health and well-being of this population.


Asunto(s)
Emigración e Inmigración , Hambre , Adulto , California/epidemiología , Cambodia/etnología , Distribución de Chi-Cuadrado , Estudios Transversales , Femenino , Humanos , Illinois/epidemiología , Modelos Logísticos , Masculino , México/etnología , Pobreza , Prevalencia , Encuestas y Cuestionarios , Texas/epidemiología , Vietnam/etnología
8.
Avian Dis ; 44(3): 582-9, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11007005

RESUMEN

Fifteen isolations of infectious bronchitis (IB) virus were made from a total of 126 Brazilian poultry flocks of all ages that were examined. These flocks (14 chicken and 1 quail) were experiencing a variety of IB-like conditions including respiratory disease, digestive and kidney problems, and drops in egg production. One of the isolates was of the Massachusetts serotype. The remainder were examined by means of cross-neutralization tests in tracheal organ cultures and were shown to belong to at least four antigenic groups, all different from ones described previously in other countries. Some, but not all, of the flocks from which they were isolated had been vaccinated against IB with vaccines of the Massachusetts serotype. In vivo protection studies showed that the MA5 vaccine (of the Massachusetts serotype) protected well against challenge with four of these isolates, representing the different serotypes reported in this study.


Asunto(s)
Infecciones por Coronavirus/veterinaria , Brotes de Enfermedades/veterinaria , Virus de la Bronquitis Infecciosa/clasificación , Enfermedades de las Aves de Corral/virología , Animales , Anticuerpos Antivirales/sangre , Brasil/epidemiología , Pollos , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/inmunología , Reacciones Cruzadas , Femenino , Virus de la Bronquitis Infecciosa/inmunología , Virus de la Bronquitis Infecciosa/aislamiento & purificación , Massachusetts , Pruebas de Neutralización , Oviposición , Enfermedades de las Aves de Corral/epidemiología , Enfermedades de las Aves de Corral/inmunología , Codorniz , Serotipificación , Vacunas Virales
9.
Org Lett ; 2(14): 2057-9, 2000 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-10891229

RESUMEN

[reaction: see text] (+)-Vellosimine has been synthesized enantiospecifically in 27% overall yield from commercially available D-(+)-tryptophan methyl ester via the asymmetric Pictet-Spengler reaction and a stereocontrolled intramolecular palladium-coupling reaction as key steps.


Asunto(s)
Ajmalina/síntesis química , Alcaloides/síntesis química , Indoles/síntesis química , Aldehídos/química , Brasil , Catálisis , Indicadores y Reactivos , Espectroscopía de Resonancia Magnética , Plantas Medicinales/química , Estereoisomerismo
10.
Arch Latinoam Nutr ; 49(3 Suppl 2): 11S-14S, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10971831

RESUMEN

In nutritional studies to assess the prevalence of iron deficiency, it has been common practice to define 3 stages of increasing severity: iron storage depletion as defined by low serum ferritin, mild iron deficiency without anemia based on laboratory evidence of iron deficient erythropoiesis (IDE), and overt iron deficiency anemia (IDA). While this approach provides a broad perspective of impaired iron status, the main liabilities of iron lack are associated only with the more advanced stage of IDA. Consequently, the hemoglobin determination can be used to screen for nutritionally significant iron deficiency. Having identified anemia, more specific laboratory studies are needed to establish iron lack as the cause. The traditional measurements of iron deficient erythropoiesis (IDE) such as a low transferrin saturation, elevated erythrocyte protoporphyrin, or decreased mean corpuscular volume are commonly used. The major drawback in using these parameters is that they are affected similarly in individuals with the anemia of chronic disease (ACD), a common form of anemia in low socioeconomic populations. Because iron stores are invariably absent in individuals with uncomplicated IDA, a low serum ferritin concentration below 20 micrograms/L confirms the diagnosis of IDA when anemia is present. The main limitation of the serum ferritin is that it is falsely elevated to within the normal range when IDA develops in individuals with concurrent infection or chronic inflammation. When this occurs in a clinical setting, a bone marrow examination is commonly performed to identify IDA. Recent investigations indicate that this cumbersome procedure can be avoided by measuring an important new iron-related measurement, the serum transferrin receptor (TfR). Because the synthesis of TfR is upregulated with tissue iron deficiency, IDA can be identified readily by an elevated serum TfR. Importantly, the serum TfR is normal in individuals with the ACD but becomes elevated if these individuals develop IDA. The optimal combination of laboratory measurements for detecting IDA is the hemoglobin, serum ferritin and serum TfR.


Asunto(s)
Anemia Ferropénica/sangre , Deficiencias de Hierro , Evaluación Nutricional , Estado Nutricional , Anemia Ferropénica/diagnóstico , Eritropoyesis , Ferritinas/sangre , Humanos , Receptores de Transferrina/sangre
11.
Mol Phylogenet Evol ; 9(1): 88-99, 1998 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9479698

RESUMEN

Variation in the nucleotide sequence of the entire mitochondrial cytochrome b gene (1140 bp) was examined for 27 individuals representing 13 species of South American rodents of the genera Ctenomys, Octodontomys, Tympanoctomys, and Spalacopus. Representatives of the family Echimyidae, Euryzygomatomys and Mesomys, were used as outgroups to test the monophyly of the Octodontinae and Ctenomyinae. Relationships among species of tuco-tucos (genus Ctenomys) were also examined including representatives of the three described subgenera and the two sperm morphs. Reciprocal monophyly of the Octodontinae and Ctenomyinae is strongly supported. Several basal relationships among species of the genus Ctenomys are poorly resolved, suggesting the possibility of a hard polytomy due to a rapid and potentially simultaneous radiation early in the history of the genus. In other cases, clades within the Ctenomyinae previously identified on the basis of allozymes, chromosomes, parasites, or skull morphology were supported. Calibrations based on the fossil record suggest that the mitochondrial cytochrome b of these caviomorphs has evolved at a rapid rate, comparable to those proposed for Mus-Rattus, and three to four times higher than ungulate rates.


Asunto(s)
Evolución Molecular , Filogenia , Roedores/genética , Animales , Composición de Base , Grupo Citocromo b/análisis , Grupo Citocromo b/genética , ADN Mitocondrial/análisis , ADN Mitocondrial/genética , Variación Genética , Datos de Secuencia Molecular , Ratas
12.
Acta Cient Venez ; 49(1): 31-7, 1998.
Artículo en Español | MEDLINE | ID: mdl-10205915

RESUMEN

A model that simulated nutritional and hypoxic stress is discussed. Wistar male adult rats were used in four groups: A1, A2, B1 and B2. A1 and A2 groups were fed with a diet whose composition was: 16% protein, 43% carbohydrate, and 6% lipids. Group B1 and B2 received the same type of diet but was restricted to 70% the amount consumed by groups A1 and A2. All groups were fed for 15 days. After these 15 days, the half of both groups were introduced into an hypobaric chamber simulating an altitude of 3,500 m for two hours. Pieces of the rats hearts were used for biochemical and ultrastructural studies. In group B a dear decrease in the body and the heart weight was observed. Also a decrement of the heart proteins concentration was noticed. On the contrary the mitochondrial proteins increased. These biochemical changes correlate with the ultrastructural changes observed in the same group in which a decrease of the myofibrilles and abnormal configurations of the mitochondria were found. The undemourishment and the hypobaric stress produced an evident alteration in the ultrastructure of the heart.


Asunto(s)
Hipoxia/complicaciones , Mitocondrias Cardíacas/ultraestructura , Miocardio/ultraestructura , Desnutrición Proteico-Calórica/complicaciones , Animales , Peso Corporal , Cardiopatías/etiología , Masculino , Microscopía Electrónica , Mitocondrias Cardíacas/química , Tamaño de los Órganos , Ratas , Ratas Wistar
13.
South Med J ; 89(6): 612-4, 1996 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8638202

RESUMEN

The use of "unconventional" or alternative medicine has been reported in up to one third of American households, yet only 28% report the use of such agents to their physician. We present here a case of near fatal sepsis and agranulocytosis. The agranulocytosis is attributed to the use of dipyrone (Dolo-Tiaminol), which the patient obtained in Mexico as a stronger form of generic "aspirin." The pyrazolone class of analgesics, of which dipyrone is a derivative, was introduced in the late 19th century and had a meteoric rise in use until an associated rise in fatal agranulocytosis was discovered. These agents were banned by the Food and Drug Administration (FDA) in 1977. Dipyrone is thought to induce agranulocytosis by inducing an antibody response. With the widespread use of alternative treatments, it is important for physicians to inquire as to the use of unprescribed drugs. Several resources are available to aid with the identification of foreign drugs.


Asunto(s)
Agranulocitosis/inducido químicamente , Antiinflamatorios no Esteroideos/efectos adversos , Dipirona/efectos adversos , Sepsis/etiología , Agranulocitosis/complicaciones , Resultado Fatal , Femenino , Humanos , Persona de Mediana Edad
14.
J Pediatr ; 128(4): 505-11, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8618184

RESUMEN

OBJECTIVES: To compare the epidemiologic, laboratory, clinical, and outcome variables of atypical (nondiarrheal) hemolytic-uremic syndrome with those of classic postdiarrheal disease. METHODS: A 24-year retrospective review of 28 episodes of atypical HUS that occurred in 22 children compared with 266 episodes of typical postdiarrheal disease in 265 children treated during the same period. RESULTS: Of the 294 episodes of HUS, 9.5% were atypical (nondiarrheal), and 18% of the patients in the atypical disease group had recurrences. Prodromal features (other than the presence or absence of diarrhea) were similar between the groups. White blood cell count and serum creatinine concentration on admission to the hospital and most abnormal blood urea nitrogen values during hospitalization were significantly lower (p = 0.02) in the patients with atypical HUS. Oliguria, anuria, and the need for dialysis were also less common (p = 0.02) in the atypical disease group. There were no deaths in the subset of patients with atypical disease; 3.4% of the patients in the typical disease group died. Although there were no statistically significant differences in the incidence of end-stage renal disease between the atypical and typical disease groups, two of the four patients with atypical disease who had recurrences also had end-stage renal disease. There were no significant differences in chronic renal sequelae between the groups one or more years after HUS. CONCLUSIONS: In contrast to reports from most other regions, patients with atypical disease in our area of the western United States have milder acute nephropathy and, with the exception of those with recurrence, do not experience worse outcomes.


Asunto(s)
Síndrome Hemolítico-Urémico , Adolescente , Niño , Preescolar , Femenino , Síndrome Hemolítico-Urémico/diagnóstico , Síndrome Hemolítico-Urémico/epidemiología , Síndrome Hemolítico-Urémico/fisiopatología , Humanos , Lactante , Masculino , Pronóstico , Recurrencia , Estudios Retrospectivos , Estaciones del Año , Utah/epidemiología
15.
Vet Rec ; 138(8): 178-80, 1996 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-8677618

RESUMEN

On the basis of virus isolation and the demonstration of specific neutralising antibody in sera, infectious bronchitis virus (IBV) 4/91 (commonly called 793B) has been shown to be present in broiler, breeder and layer flocks of chickens in many parts of western Europe and also in Thailand and Mexico. These flocks had all been vaccinated against infectious bronchitis and the need for improved methods to control this new virus, still prevalent at least four years after it was first isolated, is discussed.


Asunto(s)
Pollos/virología , Infecciones por Coronavirus/veterinaria , Virus de la Bronquitis Infecciosa/clasificación , Virus de la Bronquitis Infecciosa/aislamiento & purificación , Enfermedades de las Aves de Corral/virología , Animales , Anticuerpos Antivirales/análisis , Anticuerpos Antivirales/inmunología , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/virología , Recolección de Datos , Brotes de Enfermedades/veterinaria , Europa (Continente)/epidemiología , Incidencia , Virus de la Bronquitis Infecciosa/inmunología , México/epidemiología , Enfermedades de las Aves de Corral/diagnóstico , Enfermedades de las Aves de Corral/epidemiología , Tailandia/epidemiología , Estados Unidos/epidemiología
16.
Br J Haematol ; 92(1): 143-9, 1996 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8562387

RESUMEN

High total haemoglobin levels in homozygous sickle cell (SS) disease are a risk factor for painful crises, avascular necrosis of the femoral head, proliferative sickle retinopathy, and the acute chest syndrome. Since lowering the haemoglobin level may ameliorate these features, understanding the determinants of total haemoglobin may be of practical importance. A range of possible determinants including red cell characteristics, reticulocytes, serum iron, transferrin saturation, serum ferritin, alpha thalassaemia status, red cell mass and plasma volume, oxygen affinity, red cell survival, transferrin receptor and erythropoietin levels have been measured in 62 patients selected to provide a range of total haemoglobin and fetal haemoglobin levels. There were weak negative associations of haemoglobin with mean cell volume and mean cell haemoglobin concentration, strong negative associations with proportional reticulocyte counts, oxygen affinity, plasma volume, serum transferrin receptors, and erythropoietin levels and strong positive associations with red cell mass. Weighted analysis suggested that the statistically independent determinants of haemoglobin level were alpha thalassaemia, sex, red cell mass/body weight, plasma volume/body weight, fetal haemoglobin, and red cell count. The apparent contributions of red cell survival, P50, reticulocyte count, serum transferrin receptor and erythropoietin levels were explained by the effects of these other variables. The independent determinants as a group explained 91% of the variation in haemoglobin level.


Asunto(s)
Anemia de Células Falciformes/sangre , Hemoglobinas/análisis , Adulto , Volumen Sanguíneo , Envejecimiento Eritrocítico , Índices de Eritrocitos , Femenino , Hemoglobina Fetal/análisis , Humanos , Hierro/sangre , Masculino , Recuento de Reticulocitos , Transferrina/análisis , Talasemia alfa/sangre
17.
Ann Nutr Metab ; 38(3): 141-51, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-7979167

RESUMEN

Cellular metabolic alterations in the heart have been widely investigated under a variety of experimental conditions in which the oxygen supply was diminished. However, there is relatively scarce information about the effect of the reduced food intake and saline loading on the ultrastructural changes occurring in myocardial cells exposed to hypobaric stress during short periods of time. The purpose of the present study was to analyze the effects of hypobaric stress, NaCl intake and undernourishment on the body and heart weights and the ultrastructural changes produced in the rat myocardial cells under these conditions. The body and heart weights in all the experimental groups were determined as well as the total and mitochondrial protein concentrations. A significant decrease in body and cardiac weights was observed in both groups of undernourished animals submitted to hypobaric stress or not. On the other hand, a slight increase in the mitochondrial protein concentration was obtained in the same groups. Cardiac muscle samples were processed for light- and electron-microscopic observations. Few ultrastructural alterations were seen in the experimental groups fed with a standard diet; however, an increase in the mitochondrial size was shown in the rats that received 0.9 and 1.3% NaCl solutions. In the groups of animals with one third of the normal protein-calorie intake, more intense changes were noted; disappearance of the contractile structures, with almost complete extinction of the Z bands, was commonly observed in the rats submitted to hypobaric stress. The ultrastructural alterations seen in the undernourished animals were even more evident, showing generalized damage to the intracellular components.


Asunto(s)
Miocardio/ultraestructura , Oxígeno/administración & dosificación , Cloruro de Sodio/administración & dosificación , Animales , Presión Atmosférica , Proteínas en la Dieta/administración & dosificación , Ingestión de Energía , Masculino , Microscopía Electrónica , Mitocondrias Cardíacas/ultraestructura , Ratas , Ratas Wistar
18.
Am J Clin Nutr ; 58(5): 622-6, 1993 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8237866

RESUMEN

The present investigation was undertaken to assess the efficacy of oral iron supplementation during pregnancy by using a gastric delivery system (GDS). Three hundred seventy-six pregnant women between 16 and 35 y of age and 14 and 22 wk gestation were selected if mild anemia was present (hemoglobin concentration 80-110 g/L). The participants were randomly assigned to one of three study groups given no iron, two FeSO4 tablets (100 mg Fe) daily, or one GDS capsule (50 mg Fe) daily. Blood was obtained initially and after 6 and 12 wk for measurement of red blood cell and iron indexes, including serum transferrin receptor. There was a significant and comparable improvement in hematologic and iron-status measurements in the two groups of women given iron whereas iron deficiency evolved in women given no iron supplement. We conclude that by eliminating gastrointestinal side effects and reducing the administration frequency of an iron supplement to once daily, a GDS offers significant advantages for iron supplementation of pregnant women.


Asunto(s)
Hierro/administración & dosificación , Administración Oral , Adolescente , Adulto , Anemia/tratamiento farmacológico , Cápsulas , Sistemas de Liberación de Medicamentos , Femenino , Pruebas Hematológicas , Humanos , Hierro/metabolismo , Embarazo
19.
Genome ; 36(3): 449-58, 1993 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8349125

RESUMEN

Genome size (the amount of DNA per cell) was measured by flow-cytometric analysis in seven species of a chromosomally variable rodent genus: Ctenomys boliviensis, C. conoveri, C. frater, C. leucodon, C. lewisi, C. opimus, and C. steinbachi. The mean genome size of these species was 7.19 pg DNA and little inter- and intra-specific variation was observed. Genome size was not correlated with diploid number, suggesting that chromosomal evolution at this level is independent of total DNA content. A hypothetical taxonomic unit optimization procedure was carried out using genome size change on a Wagner tree derived from allozyme data. Allozyme evolution and genome size change are linked by a weak, but significant, negative correlation suggestive of preferential genic evolution in the absence of genome size evolution.


Asunto(s)
Evolución Biológica , Genoma , Roedores/genética , Animales , Bolivia , Cromosomas , ADN/análisis , ADN/genética , Variación Genética , Filogenia , Especificidad de la Especie
20.
Br J Haematol ; 84(2): 301-4, 1993 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8398834

RESUMEN

Serum transferrin receptor (TfR) levels were measured in 182 children with homozygous sickle cell (SS) disease, 47 with sickle cell-haemoglobin C (SC) disease and 41 normal (AA) controls on their eighth birthday. Highly significant elevations occurred in SS compared to SC disease and in SC disease compared to AA controls. Females had higher levels than males in controls but lower levels than males in SS and SC disease. In SS disease, serum TfR levels tended to rise with age from 2 to 8 years, the change within individuals correlating with a change in reticulocyte count (r = 0.38, P = 0.017) and fall in fetal haemoglobin levels (r = -0.51, P = 0.004). Serum TfR levels did not change with infection or painful crisis but were markedly elevated in hypersplenism and fell following splenectomy in these subjects. In the aplastic crisis, serum TfR levels tended to rise following clinical presentation and then fall, reflecting the reticulocyte counts. These observations are consistent with serum TfR levels being a useful indicator of the degree of erythropoietic expansion in sickle cell disease.


Asunto(s)
Anemia de Células Falciformes/sangre , Receptores de Transferrina/análisis , Transferrina/análisis , Factores de Edad , Niño , Preescolar , Femenino , Enfermedad de la Hemoglobina SC/sangre , Humanos , Lactante , Masculino , Factores Sexuales , Esplenectomía
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