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1.
J Clin Microbiol ; 58(6)2020 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-32188689

RESUMO

Diagnostic tests for foot-and-mouth disease (FMD) include the detection of antibodies against either the viral nonstructural proteins or the capsid. The detection of antibodies against the structural proteins (SP) of the capsid can be used to monitor seroconversion in both infected and vaccinated animals. However, SP tests need to be tailored to the individual FMD virus (FMDV) serotype and their sensitivity may be affected by antigenic variability within each serotype and mismatching between test reagents. As a consequence, FMD reference laboratories are required to maintain multiple type-specific SP assays and reagents. A universal SP test would simplify frontline diagnostics and facilitate large-scale serological surveillance and postvaccination monitoring. In this study, a highly conserved region in the N terminus of FMDV capsid protein VP2 (VP2N) was characterized using a panel of intertype-reactive monoclonal antibodies. This revealed a universal epitope in VP2N which could be used as a peptide antigen to detect FMDV-specific antibodies against all types of the virus. A VP2-peptide enzyme-linked immunosorbent assay (VP2-ELISA) was optimized using experimental and reference antisera from immunized, convalescent, and naïve animals (n = 172). The VP2-ELISA is universal and simple and provided sensitive (99%) and specific (93%) detection of antibodies to all FMDV strains used in this study. We anticipate that this SP test could have utility for serosurveillance during virus incursions in FMD-free countries and as an additional screening tool to assess FMD virus circulation in countries where the disease is endemic.


Assuntos
Vírus da Febre Aftosa , Febre Aftosa , Animais , Anticorpos Antivirais , Capsídeo , Proteínas do Capsídeo/genética , Bovinos , Ensaio de Imunoadsorção Enzimática , Epitopos , Febre Aftosa/diagnóstico , Testes Sorológicos
2.
Sci Total Environ ; 348(1-3): 211-30, 2005 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-16162326

RESUMO

Heavy metal escapement associated with ore trucks is known to occur along the DeLong Mountain Regional Transportation System (DMTS) haul road corridor in Cape Krusenstern National Monument, northwest Alaska. Heavy metal concentrations in Hylocomium splendens moss (n = 226) were used in geostatistical models to predict the extent and pattern of atmospheric deposition of Cd and Pb on Monument lands. A stratified grid-based sample design was used with more intensive sampling near mine-related activity areas. Spatial predictions were used to produce maps of concentration patterns, and to estimate the total area in 10 moss concentration categories. Heavy metal levels in moss were highest immediately adjacent to the DMTS haul road (Cd > 24 mg/kg dw; Pb > 900 mg/kg dw). Spatial regression analyses indicated that heavy metal deposition decreased with the log of distance from the DMTS haul road and the DMTS port site. Analysis of subsurface soil suggested that observed patterns of heavy metal deposition reflected in moss were not attributable to subsurface lithology at the sample points. Further, moss Pb concentrations throughout the northern half of the study area were high relative to concentrations previously reported from other Arctic Alaska sites. Collectively, these findings indicate the presence of mine-related heavy metal deposition throughout the northern portion of Cape Krusenstern National Monument. Geospatial analyses suggest that the Pb depositional area extends 25 km north of the haul road to the Kisimilot/Iyikrok hills, and possibly beyond. More study is needed to determine whether higher moss heavy metal concentrations in the northernmost portion of the study area reflect deposition from mining-related activities, weathering from mineralized Pb/Zn outcrops in the broader region, or a combination of the two. South of the DMTS haul road, airborne deposition appears to be constrained by the Tahinichok Mountains. Heavy metal levels continue to diminish south of the mountains, reaching a minimum in the southernmost portion of the study area near the Igichuk Hills (45 km from the haul road). The influence of the mine site was not studied.


Assuntos
Bryopsida/química , Cádmio/análise , Chumbo/análise , Poluentes do Solo/análise , Alaska , Monitoramento Ambiental , Geografia , Mineração , Meios de Transporte , Estados Unidos , United States Government Agencies , Vento
3.
Am J Clin Nutr ; 63(1): 130-7, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8604660

RESUMO

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease characterized by progressive muscle atrophy and weakness. Although dysphagia is a universal feature of this illness, the nutritional and metabolic status of ALS patients has received little attention. We performed serial measurements of muscle power, body composition, energy expenditure, nitrogen balance, and dietary intake on ALS patients on three occasions over 6 mo in the General Clinical Research Center of the University of Kentucky Medical Center. Data were analyzed in reference to the time of death. Regression analysis demonstrated progressive decreases in body fat, lean body mass, muscle power, and nitrogen balance and an increase in resting energy expenditure as death approached. The changes in body composition were greater in males. Energy and protein consumption averaged 84% and 126% of the recommended dietary allowances, respectively, but did not correlate with complaints of dysphagia. We conclude that ALS patients have a chronically deficient intake of energy and recommended augmentation of energy intake rather than the consumption of high-protein nutritional supplements.


Assuntos
Esclerose Lateral Amiotrófica/fisiopatologia , Morte , Estado Nutricional/fisiologia , Adulto , Idoso , Esclerose Lateral Amiotrófica/sangue , Antropometria , Composição Corporal , Índice de Massa Corporal , Cátions/sangue , Proteínas Alimentares/administração & dosagem , Progressão da Doença , Ingestão de Energia , Metabolismo Energético , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nitrogênio/metabolismo
4.
Reprod Toxicol ; 3(2): 101-13, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2520509

RESUMO

The present study was performed to evaluate the involvement of reduced testosterone in ethanol-induced impairment of male reproductive tract development. In vivo and in vitro gonadotropin (hCG)-stimulated steroidogenesis were examined in CFW mice as a function of chronic ethanol treatment during pubertal development. Chronic ethanol treatment from ages 20 to 49 days impaired testicular growth from ages 35 days (29 +/- 2 mg vs 37 +/- 2 mg for pair-fed controls) to 50 days (42 +/- 2 mg vs 63 +/- 2 mg for pair-fed controls). Consistent with a reduction in testicular weight, testicular content of androstenedione, testosterone, and dihydrotestosterone (DHT) was depressed in ethanol-treated mice. At age 50 days, the content (expressed as pg/testis) of androstenedione, testosterone, and DHT was reduced in ethanol-treated animals by 49%, 31%, and 38%, respectively, as compared to that of their respective controls. However, no difference in plasma (ng/mL) or testicular (pg/mg protein) concentrations of steroids was observed. Except for the DHT response at ages 35 to 40 days, neither in vivo nor in vitro steroidogenesis was impaired by chronic ethanol treatment at ages 26 to 50 days; similarly, the acute ethanol effect on steroidogenesis was unaffected. However, an adaptive increase (54%-173%) in the in vivo testosterone response to hCG was seen at ages 26 to 40 days. The data indicate that 1) chronic ethanol treatment does not impair gonadotropin-stimulated steroidogenesis or result in tolerance to acute ethanol effects on steroidogenesis in older animals; and 2) ethanol-induced reduction in testosterone is not a likely mechanism for delayed sexual maturation.


Assuntos
Etanol/toxicidade , Células Intersticiais do Testículo/fisiologia , Maturidade Sexual/efeitos dos fármacos , Envelhecimento/metabolismo , Androstenodiona/biossíntese , Animais , Gonadotropina Coriônica/farmacologia , Di-Hidrotestosterona/metabolismo , Etanol/sangue , Feminino , Técnicas In Vitro , Células Intersticiais do Testículo/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos , Tamanho do Órgão/efeitos dos fármacos , Gravidez , Proteínas/metabolismo , Testículo/efeitos dos fármacos , Testículo/crescimento & desenvolvimento , Testículo/metabolismo , Testosterona/biossíntese
5.
Reprod Toxicol ; 3(2): 91-100, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2520516

RESUMO

The purpose of the present study was to evaluate the sensitivity of testicular steroidogenesis during pubertal development to inhibition by ethanol. In vivo and in vitro human chorionic gonadotropin (hCG)-stimulated steroidogenesis were examined in CFW mice as a function of age. Plasma androstenedione, testosterone, and dihydrotestosterone (DHT) increased from ages 23 to 60 days in control mice. Acute ethanol treatment (3 g/kg) yielded static levels of androstenedione (0.45 +/- 0.03 ng/mL), testosterone (6.4 +/- 0.56 ng/mL), and DHT (2.3 +/- 0.18 ng/mL) from ages 23 to 60 days, 30 to 60 days, and 35 to 60 days, respectively, resulting in reduction of plasma androstenedione, testosterone, and DHT (P less than 0.05) relative to control values, but not until ages 35, 50, and 45 days, respectively. A similar insensitivity of the prepubertal testis to ethanol was seen in vitro. Inhibition of in vitro androstenedione and testosterone accumulation was seen only after ages 26 and 45 days, respectively. The data indicate that testosterone production by the pubertal testis is relatively insensitive to direct inhibition by ethanol. Previous studies have shown that chronic ethanol treatment of adolescent mice delays testicular maturation. The present study suggests that if chronic ethanol-induced delayed testicular development were due to impaired steroidogenesis, such impairment would be secondary to reduced gonadotropin stimulation and/or due to a chronic, rather than an acute, effect of ethanol.


Assuntos
Etanol/farmacologia , Testículo/metabolismo , Testosterona/biossíntese , Envelhecimento/metabolismo , Androstenodiona/sangue , Androstenodiona/metabolismo , Animais , Gonadotropina Coriônica/farmacologia , Di-Hidrotestosterona/sangue , Di-Hidrotestosterona/metabolismo , Etanol/sangue , Feminino , Técnicas In Vitro , Células Intersticiais do Testículo/efeitos dos fármacos , Células Intersticiais do Testículo/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos , Gravidez , Biossíntese de Proteínas , Maturidade Sexual/efeitos dos fármacos , Testículo/efeitos dos fármacos
6.
Mutat Res ; 278(1): 47-60, 1992 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1370119

RESUMO

The mutagenic potential of chronic treatments of male CF-1 mice with ethanol and delta 9-tetrahydrocannibinol (THC), and their comutagenic potential with a known mutagenic agent, Trenimon, were examined. This was accomplished by measuring the frequency of dominant lethal mutations arising from mating of treated males with nontreated females. Adult male mice were treated with 5% (v/v) ethanol as part of a liquid diet (28% ethanol-derived calories) for five weeks; 10 mg/kg body weight (p.o.) THC every two days for five weeks; a single injection of Trenimon (0.125 mg/kg, i.p.) on day 28 of diet treatment; and all combinations of treatments. The control group was pair-fed a liquid diet in which isocaloric sucrose replaced ethanol; these males were also given sesame oil (vehicle for THC) and saline (vehicle for Trenimon) on the same schedule as that for the treated males. Neither body weights nor hematocrits were adversely affected by any treatment. Both ethanol and Trenimon treatments resulted in a small (8-9%; p less than 0.05) decrease in testicular weight. The effect of combined treatment with ethanol and Trenimon was roughly additive. Treatment with THC had no effect on testicular weight. Seminal vesicle weights were not affected by any treatment. Treatments were without significant effect on fertility, as measured by the frequency of males producing pregnancies. Ethanol and Trenimon treatments produced approximately 3- and 7-fold increases, respectively in the frequencies of preimplantational loss over that seen for the control group (7.3%), resulting in significant ethanol and Trenimon effects (p less than 0.001). No interactive effects of ethanol and Trenimon treatments were noted. Frequencies of dead fetuses per pregnancy in the ethanol- and Trenimon-treated groups were increased approximately 2.5- and 4-fold, respectively, over the control value of approximately 16%. However, the effect of combined treatments was not greater than that due to Trenimon alone, resulting in Trenimon and ethanol effects (p less than 0.001) and ethanol-Trenimon interaction (p less than 0.001). The calculated mutation index resulting from each treatment yielded significant (p less than 0.001) ethanol- and Trenimon-induced effects. In contrast to effects of ethanol and Trenimon treatments, THC, given alone, or in combination with ethanol and/or Trenimon, had no effect on either preimplantational loss, fetal mortality or the resulting mutation index. The data suggest that chronic ethanol treatment, at levels resulting in minimal fertility impairment, increases the frequency of dominant lethal mutations. In contrast, chronic treatment with THC, as administered in the present study, appears to be without effect.(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Dronabinol/toxicidade , Etanol/toxicidade , Genes Letais/efeitos dos fármacos , Mutagênicos/toxicidade , Triaziquona/toxicidade , Análise de Variância , Animais , Interações Medicamentosas , Feminino , Fertilidade , Masculino , Camundongos , Camundongos Endogâmicos , Mutagênese , Testes de Mutagenicidade , Tamanho do Órgão , Gravidez , Valores de Referência , Glândulas Seminais/anatomia & histologia , Glândulas Seminais/efeitos dos fármacos , Testículo/anatomia & histologia , Testículo/efeitos dos fármacos
7.
Clin Nucl Med ; 19(6): 504-7, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8062468

RESUMO

Optimal preparation for I-131 scanning and therapy of differentiated thyroid carcinoma requires use of a low iodine diet (< or = 50 micrograms iodine per day) to enhance the delivery of I-131 to thyroid remnants or carcinoma. Because there are no commercial low-iodine tube-feeding diets, the authors formulated and tested a suitable diet that is appropriate for home preparation using commonly available ingredients. A patient was placed on this diet in anticipation of radioiodine therapy after surgical resection of a thyroid carcinoma recurrence in his neck. This patient reduced his 24-hour urinary iodine excretion from 378 micrograms iodine to 13 micrograms iodine after 15 days on the diet. Analysis of the diet reveals that it is nutritionally complete and delivers only 18.2 micrograms of iodine for each 1000 kcal. This diet should improve I-131 therapy of differentiated thyroid carcinoma in patients requiring tube feedings.


Assuntos
Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/radioterapia , Alimentos Formulados , Radioisótopos do Iodo , Iodo/administração & dosagem , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/radioterapia , Adenocarcinoma/terapia , Adulto , Idoso , Nutrição Enteral , Humanos , Radioisótopos do Iodo/uso terapêutico , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Necessidades Nutricionais , Cintilografia , Neoplasias da Glândula Tireoide/terapia , Tireoidectomia
9.
Biochem J ; 119(5): 839-48, 1970 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-5531181

RESUMO

1. DNA polymerase activity is present in both nuclear and supernatant fractions prepared from rapidly dividing L929 mouse cells. 2. Nuclear preparations are 2-5 times more active with added native DNA as template and the supernatant fractions show an equivalent preference for heat-denatured DNA. 3. Isolated nuclei can carry on limited DNA synthesis in the absence of added template but are stimulated five- to ten-fold by addition of 50mug of native DNA per assay. 4. DNA polymerase activity can be released from intact nuclei by ultrasonic treatment or by extraction with 1.5m-potassium chloride. 5. The activities in nuclear and supernatant fractions, with their preferred templates, respond similarly to changes in pH and Mg(2+) and K(+) concentrations. 6. Maximal enzyme activity is approached with 40mug of DNA per assay and activation of the DNA template by treatment with deoxyribonuclease does not decrease the amount of DNA required to reach saturation. 7. The nuclear enzyme, incubated with native DNA, is markedly inhibited by the addition of heat-denatured DNA to the assay. In contrast, the supernatant DNA polymerase activity on denatured templates is not affected by the presence of native DNA. 8. The nuclear enzyme exhibits high activity in the absence of one or more deoxyribonucleoside triphosphates but this is much diminished after partial purification of the enzyme by precipitation at pH5 and fractionation on Sephadex G-200 columns. 9. The (3)H-labelled DNA products formed by Sephadex-purified nuclear and supernatant fractions, with their preferred templates, were found to be resistant to treatment with exonuclease I. Alkali-denaturation of the (3)H-labelled DNA products rendered them susceptible to attack by exonuclease I. 10. Analysis of the products on alkaline sucrose density gradients suggests that the newly synthesized material may not be covalently bound to the original DNA template. 11. By using their preferred templates the specific activity of supernatant fractions varies markedly with the position of the cells in the cell-cycle, but the specific activity of nuclear fractions varies only slightly.


Assuntos
Núcleo Celular/enzimologia , Citoplasma/enzimologia , DNA Nucleotidiltransferases/análise , Animais , Divisão Celular , Linhagem Celular , Centrifugação com Gradiente de Concentração , Cromatografia em Gel , Técnicas de Cultura , DNA/biossíntese , DNA Nucleotidiltransferases/isolamento & purificação , Replicação do DNA , Desoxirribonucleases , Camundongos , Desnaturação de Ácido Nucleico , Nucleotídeos , Moldes Genéticos , Trítio , Ultracentrifugação
10.
Muscle Nerve ; 20(3): 330-5, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9052812

RESUMO

We evaluated the feasibility of using upper extremity anthropometrics to monitor the clinical status of 18 patients with amyotrophic lateral sclerosis (ALS). The bone-free arm muscle area (AMA) was computed using measurement of triceps skinfold thickness and the mid-upper arm circumference according to published formulae. The AMA correlated significantly with body mass, isokinetic muscle force generation, cross-sectional muscle area on computerized tomography scanning, and pulmonary functions including forced vital capacity and maximal voluntary ventilation. Serial determinations of AMA demonstrated a decline in 10 of 13 patients over 6 months. We pilot tested the use of AMA in a clinical trial of ciliary neurotrophic factor (CNTF) in the treatment of ALS. The AMA progressively decreased by 13%, 15%, and 30% in ALS patients treated with 0 microg CNTF/kg, 15 microg CNTF/kg, and 30/microg CNTF/kg, respectively, over a 9-month treatment period. We conclude that measurement of AMA provides a simple, inexpensive method to monitor the progression of muscle atrophy in ALS patients. The technique does not require effort on the part of the patient and as such, appears to have potential utility as an outcome measure in clinical drug trials.


Assuntos
Esclerose Lateral Amiotrófica/patologia , Esclerose Lateral Amiotrófica/fisiopatologia , Antropometria , Braço/patologia , Adulto , Idoso , Esclerose Lateral Amiotrófica/tratamento farmacológico , Fator Neurotrófico Ciliar , Método Duplo-Cego , Estudos de Viabilidade , Feminino , Humanos , Pulmão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Músculos/diagnóstico por imagem , Músculos/fisiopatologia , Proteínas do Tecido Nervoso/uso terapêutico , Tomografia Computadorizada por Raios X , Torque
11.
Toxicol Appl Pharmacol ; 100(1): 62-85, 1989 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2763303

RESUMO

The present study was conducted to provide biochemical and morphological evidence for ethanol-induced impairment of testicular development. The specific activities of testicular postmeiotic enzyme markers--sorbitol dehydrogenase (SDH), lactate dehydrogenase (LDH), and alpha-glycerophosphate dehydrogenase (GDH)--increased with age in CFW mice from ages 23 to 60 days, providing a biochemical measure of testicular development during puberty. Chronic ethanol treatment via liquid diets from ages 20 to 55 days resulted in decreased activities of SDH and LDH at ages 40 and 44 days, and of GDH at ages 34, 40, and 44 days. These decreases were consistent with an arrest in the developmental increase in SDH, LDH, and GDH at ages 31 +/- 0.6, 31 +/- 2.6, and 24 +/- 0.5 days, respectively. After 29 days of ethanol treatment (age 50 days), testicular weights, epididymal sperm content, and sperm motility were reduced, relative to controls, by 37, 83, and 60%, respectively (p less than 0.05). Epididymal weights were unaffected. Light microscopic evaluation of testes revealed disorganization of spermatogenesis, germ cell degeneration, decreased tubular luminal diameter, and vacuolation of Sertoli cells in ethanol-treated mice at age 50 days. Electron microscopic analysis showed that germ cell degeneration was not restricted to a specific cell type. Stage IX-XI tubules were observed in which spermatids had been retained and underwent phagocytosis within the Sertoli cell. Sertoli cells showed evidence of atypical nuclear invaginations. Sertoli cells underwent degenerative changes and were sloughed into the rete testis. However, relative Leydig cell size, as well as fractional volume occupied by the nucleus, mitochondria, and endoplasmic reticulum were unaffected by ethanol. The data (1) confirm previous findings suggesting ethanol-induced delayed testicular development; (2) suggest that certain aspects of testicular development are arrested relatively early in ethanol treatment (4-11 days); and (3) indicate that the Sertoli cell, rather than the Leydig cell, is the primary target with regard to the deleterious effect of chronic ethanol treatment on testicular maturation.


Assuntos
Etanol/toxicidade , Testículo/efeitos dos fármacos , Administração Oral , Animais , Etanol/sangue , Células Intersticiais do Testículo/efeitos dos fármacos , Masculino , Camundongos , Oxirredutases/metabolismo , Maturidade Sexual , Testículo/enzimologia , Testículo/crescimento & desenvolvimento , Testículo/patologia
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