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1.
Affect Sci ; 3(3): 616-627, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36385910

RESUMEN

Repetitive negative thinking (RNT) is a transdiagnostic risk factor for internalizing psychopathology, and theoretical models suggest that RNT may maintain symptoms by interfering with psychophysiological habituation. The present study therefore examined associations between RNT and habituation within and between study sessions. Community members (N=86) completed a habituation task involving exposure to acoustic probes at up to five sessions spaced 7 days apart on average. Eyeblink startle response was measured using the electromyography startle magnitude. Self-reported anxiety was assessed before and after the habituation task at each session. Multilevel growth curve modeling indicated that RNT was associated with a higher "floor" (i.e., asymptote) of startle responding as evidenced by reduced within-session startle habituation at later sessions. Results suggest that RNT may disrupt startle habituation and are consistent with theoretical models proposing that RNT sustains physiological activation to support avoidance of negative emotional contrasts or perceived future threats. Supplementary Information: The online version contains supplementary material available at 10.1007/s42761-022-00121-w.

2.
Psychol Med ; 52(7): 1208-1221, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35550677

RESUMEN

Psychomotor slowing is a key feature of depressive disorders. Despite its great clinical importance, the pathophysiology and prevalence across different diagnoses and mood states are still poorly understood. Actigraphy allows unbiased, objective, and naturalistic assessment of physical activity as a marker of psychomotor slowing. Yet, the true effect-sizes remain unclear as recent, large systematic reviews are missing. We conducted a novel meta-analysis on actigraphically measured slowing in depression with strict inclusion and exclusion criteria for diagnosis ascertainment and sample duplications. Medline/PubMed and Web-of-Science were searched with terms combining mood-keywords and actigraphy-keywords until September 2021. Original research measuring actigraphy for ⩾24 h in at least two groups of depressed, remitted, or healthy participants and applying operationalized diagnosis was included. Studies in somatically ill patients, N < 10 participants/group, and studies using consumer-devices were excluded. Activity-levels between groups were compared using random-effects models with standardized-mean-differences and several moderators were examined. In total, 34 studies (n = 1804 patients) were included. Patients had lower activity than controls [standardized mean difference (s.m.d.) = -0.78, 95% confidence interval (CI) -0.99 to -0.57]. Compared to controls, patients with unipolar and bipolar disorder had lower activity than controls whether in depressed (unipolar: s.m.d. = -0.82, 95% CI -1.07 to -0.56; bipolar: s.m.d. = -0.94, 95% CI -1.41 to -0.46), or remitted/euthymic mood (unipolar: s.m.d. = -0.28, 95% CI -0.56 to 0.0; bipolar: s.m.d. = -0.92, 95% CI -1.36 to -0.47). None of the examined moderators had any significant effect. To date, this is the largest meta-analysis on actigraphically measured slowing in mood disorders. They are associated with lower activity, even in the remitted/euthymic mood-state. Studying objective motor behavior via actigraphy holds promise for informing screening and staging of affective disorders.


Asunto(s)
Trastorno Bipolar , Depresión , Actigrafía , Humanos , Trastornos del Humor
3.
J Psychiatr Res ; 135: 68-75, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33450467

RESUMEN

Affect dynamics reflect individual differences in how emotional information is processed, and may provide insights into how depressive episodes develop. To extend prior studies that examined affect dynamics in currently depressed individuals, the present study tested in 68 non-depressed young adults whether three well-established risk factors for major depressive disorder (MDD) - (a) past episodes of MDD, (b) family history of MDD, and (c) reduced neurophysiological responses to reward - predicted mean levels, instability, or inertia (i.e., inflexibility) of positive affect (PA) and/or negative affect (NA). Momentary PA and NA were assessed up to 6 times per day for 14 days (mean number of surveys completed = 45.89). MDD history and family history of MDD were assessed via semi-structured interview, and neurophysiological responses to reward were indexed using the Reward Positivity, an event-related potential related to depression. After adjusting for current depressive symptoms, results indicated that (a) past episodes of MDD predicted higher mean levels of NA, (b) family history of MDD predicted greater PA inertia, and (c) blunted reactivity to reward predicted greater NA inertia. Collectively, these results suggest that elevated mean levels of NA and inflexibility of PA and NA may be potential mechanisms that confer risk for depression.


Asunto(s)
Trastorno Depresivo Mayor , Evaluación Ecológica Momentánea , Afecto , Depresión/epidemiología , Trastorno Depresivo Mayor/epidemiología , Humanos , Factores de Riesgo , Adulto Joven
4.
Opt Express ; 16(17): 13158-67, 2008 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-18711554

RESUMEN

The optical loss of whispering gallery modes of resonantly excited microresonator spheres is determined by optical lifetime measurements. The phase-shift cavity ring-down technique is used to extract ring-down times and optical loss from the difference in amplitude modulation phase between the light entering the microresonator and light scattered from the microresonator. In addition, the phase lag of the light exiting the waveguide, which was used to couple light into the resonator, was measured. The intensity and phase measurements were fully described by a model that assumed interference of the cavity modes with the light propagating in the waveguide.


Asunto(s)
Diseño Asistido por Computadora , Modelos Teóricos , Óptica y Fotónica/instrumentación , Refractometría/instrumentación , Transductores , Simulación por Computador , Diseño de Equipo , Análisis de Falla de Equipo , Luz , Miniaturización , Dispersión de Radiación
5.
Theor Appl Genet ; 112(4): 688-98, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16369760

RESUMEN

Grain yield and associated agronomic traits are important factors in wheat (Triticum aestivum L.) improvement. Knowledge regarding the number, genomic location, and effect of quantitative trait loci (QTL) would facilitate marker-assisted selection and the development of cultivars with desirable characteristics. Our objectives were to identify QTLs directly and indirectly affecting grain yield expression. A population of 132 F12 recombinant inbred lines (RILs) was derived by single-seed descent from a cross between the Chinese facultative wheat Ning7840 and the US soft red winter wheat Clark. Phenotypic data were collected for 15 yield and other agronomic traits in the RILs and parental lines from three locations in Oklahoma from 2001 to 2003. Twenty-nine linkage groups, consisting of 363 AFLP and 47 SSR markers, were identified. Using composite interval mapping (CIM) analysis, 10, 16, 30, and 14 QTLs were detected for yield, yield components, plant adaptation (shattering and lodging resistance, heading date, and plant height), and spike morphology traits, respectively. The QTL effects ranged from 7 to 23%. Marker alleles from Clark were associated with a positive effect for the majority of QTLs for yield and yield components, but gene dispersion was the rule rather than the exception for this RIL population. Often, QTLs were detected in proximal positions for different traits. Consistent, co-localized QTLs were identified in linkage groups 1AL, 1B, 4B, 5A, 6A, and 7A, and less consistent but unique QTLs were identified on 2BL, 2BS, 2DL, and 6B. Results of this study provide a benchmark for future efforts on QTL identification for yield traits.


Asunto(s)
Cromosomas de las Plantas , Sitios de Carácter Cuantitativo , Carácter Cuantitativo Heredable , Triticum/genética , Mapeo Cromosómico , Cruzamientos Genéticos , Ligamiento Genético , Fenotipo
6.
Phytopathology ; 96(5): 496-500, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-18944309

RESUMEN

ABSTRACT Powdery mildew, caused by Blumeria graminis f. sp tritici, is an important foliar disease of wheat worldwide. Pyramiding race-specific genes into a single cultivar and combining race-specific resistance genes with durable resistance genes are the preferred strategies to improve the durability of powdery mildew resistance. The objectives of this study were to characterize a powdery mildew resistance gene in Suwon 92 and identify gene-specific or tightly linked molecular markers for marker-assisted selection (MAS). A population of recombinant inbred lines (RILs) was derived by single seed descent from a cross between Suwon 92 and a susceptible cultivar, CI 13227. The RILs were screened for adult-plant infection type of powdery mildew and characterized with amplified fragment length polymorphism (AFLP) and simple sequence repeat (SSR) markers. The linked markers explained 41.3 to 69.2% of the phenotypic variances measured in 2 years. A morphological marker, hairy glume, was also associated with powdery mildew resistance in Suwon 92, and explained 43 to 51% of the phenotypic variance. The powdery mildew resistance gene in Suwon 92 was located on the short arm of chromosome 1A where Pm3 was located. Two gene-specific markers were developed based on the sequence of the cloned Pm3b gene. These two markers, which were mapped at the same locus in the peak region of the LOD score for the RIL population, explained most of the phenotypic variance for powdery mildew resistance in the RIL population. The powdery mildew resistance in Suwon 92 is most likely conditioned by the Pm3 locus. The gene markers developed herein can be directly used for MAS of some of the Pm3 alleles in breeding programs.

7.
Theor Appl Genet ; 112(1): 51-7, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16189660

RESUMEN

Genetic improvement of aluminum (Al) tolerance is one of the cost-effective solutions to improve wheat (Triticum aestivum) productivity in acidic soils. The objectives of the present study were to identify quantitative trait loci (QTL) for Al-tolerance and associated PCR-based markers for marker-assisted breeding utilizing cultivar Atlas 66. A population of recombinant inbred lines (RILs) from the cross Atlas 66/Century was screened for Al-tolerance by measuring root-growth rate during Al treatment in hydroponics and root response to hematoxylin stain of Al treatment. After 797 pairs of SSR primers were screened for polymorphisms between the parents, 131 pairs were selected for bulk segregant analysis (BSA). A QTL analysis based on SSR markers revealed one QTL on the distal region of chromosome arm 4DL where a malate transporter gene was mapped. This major QTL accounted for nearly 50% of the phenotypic variation for Al-tolerance. The SSR markers Xgdm125 and Xwmc331 were the flanking markers for the QTL and have the potential to be used for high-throughput, marker-assisted selection in wheat-breeding programs.


Asunto(s)
Aluminio/metabolismo , Mapeo Cromosómico , Cromosomas de las Plantas , Sitios de Carácter Cuantitativo , Triticum/genética , Ligamiento Genético , Marcadores Genéticos , Genotipo , Fenotipo , Polimorfismo Genético , Triticum/fisiología
8.
Theor Appl Genet ; 110(2): 244-51, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15672257

RESUMEN

Slow rusting is considered a crucial component of durable resistance to wheat leaf rust caused by Puccinia triticina and is often expressed in the form of a prolonged latent period. Selection for a longer latent period is considered an effective approach to developing wheat cultivars with improved durable resistance to leaf rust. A recombinant inbred line (RIL) population derived from CI 13227 (long latent period) x Suwon 92 (short latent period) was phenotyped for latent period in two greenhouse experiments in separate years, and amplified fragment length polymorphism (AFLP) and simple sequence repeat (SSR) markers were analyzed in the same population. Among the RILs, the frequency distribution for latent period was continuous, and latent period was highly correlated between years (r=0.94, P<0.0001). A quantitative trait locus (QTL) prolonging the latent period of P. triticina, designated as QLrlp.osu-2DS, explained 42.8% and 54.5% of the phenotypic and genetic variance in the two experiments, respectively. QLrlp.osu-2DS was mapped on the distal region of chromosome 2DS. Two other QTLs for latent period, QLrlp.osu-2B and QLrlp.osu-7BL, were localized on chromosome 2B and the long arm of chromosome 7B, respectively. Multiple regression analysis showed that these three QTLs collectively explained 58.0% and 73.8% of the phenotypic and genetic variance over two experiments, respectively. Fourteen RILs that carried all three alleles for long latent period at three AFLP loci flanking QLrlp.osu-2DS, QLrlp.osu-2B, and QLrlp.osu-7BL had a mean latent period of 12.5 days, whereas 13 RILs without any long-latent-period alleles at the corresponding loci had a mean latent period of 7.4 days. Three SSR markers closely linked to these QTLs have potential to be applied in marker-assisted selection for prolonged latent period in wheat.


Asunto(s)
Basidiomycota/patogenicidad , Inmunidad Innata/genética , Enfermedades de las Plantas/genética , Sitios de Carácter Cuantitativo , Triticum/genética , Mapeo Cromosómico , Enfermedades de las Plantas/microbiología , Factores de Tiempo , Triticum/anatomía & histología , Triticum/microbiología
9.
Transplantation ; 71(9): 1348-9, 2001 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-11397977

RESUMEN

BACKGROUND: Although rare, renal cell carcinoma has been found during renal recovery for cadaveric organ transplantation. Previously, we reported this incidence to be 0.9%. In one cadaveric donor, the liver and left kidney had been transplanted before the discovery of renal cell carcinoma (T1) in the right kidney. METHODS: We retrospectively reviewed the medical records of two patients who had received cadaveric allografts from a donor with a known renal cell carcinoma. RESULTS: Both patients have been followed for 4 years with blood chemistries and chest x-ray every 3 months for year 1, every 4 months for years 2 and 3, and every 6 months thereafter. They also underwent allograft ultrasound every 6 months and an annual CT scan of the abdomen. Both patients have shown no evidence of metastatic disease throughout their follow-up. DISCUSSION: In the rare instance that a patient receives an organ from a cadaveric donor with a known renal cell carcinoma, it is mandatory to follow these patients closely observing for both allograft recurrence and metastatic disease.


Asunto(s)
Carcinoma de Células Renales/patología , Neoplasias Renales/patología , Trasplante de Riñón/métodos , Trasplante de Hígado/patología , Recurrencia Local de Neoplasia , Cadáver , Femenino , Estudios de Seguimiento , Humanos , Trasplante de Hígado/efectos adversos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Donantes de Tejidos
10.
Transplantation ; 67(11): 1438-40, 1999 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-10385082

RESUMEN

BACKGROUND: With the exception of primary central nervous system tumors, organ recovery is no longer considered from donors with known malignancy. Because intrathoracic and intraabdominal organs are usually recovered before the kidneys, we examined the incidence of renal cell carcinoma in cadaveric donor kidneys at the time of organ recovery. This would establish the theoretical risk of transplanting donor organs from a patient with a known renal malignancy. METHODS: In cooperation with the Louisiana Organ Procurement Agency, we reviewed the records of all patients who were cadaveric kidney donors in the state of Louisiana between September 1991 and October 1997. Information was reviewed and analyzed on donor age, sex, race, past medical/surgical history, cause of death, and the findings at the time of organ recovery. RESULTS: A total of 553 consecutive cadaveric donors were identified, with 1106 kidneys recovered. Of the 553 cadaveric donors, 5 (0.9%) were noted to have an incidental renal cell carcinoma. All tumors were identified in separate donors; that is, none of the tumors were bilateral. None of the five donors had documented symptoms referable to their urinary tract. All tumors were either T1 or T2 by the tumor, node, metastasis classification system, and no evidence of nodal or distant metastatic disease was present. In one case, the contralateral kidney, heart, and liver were transplanted before the tumor was identified. In the remaining four cases, all organs (renal and nonrenal) were discarded. CONCLUSIONS: Renal cell carcinoma is rarely found during renal recovery from a cadaveric donor. However, because the kidneys are usually recovered after the intrathoracic and intraabdominal organs, careful palpation of the kidneys and exploration of any abnormalities is mandated to avoid transplanting any organs from a donor with a known renal malignancy.


Asunto(s)
Carcinoma de Células Renales/epidemiología , Neoplasias Renales/epidemiología , Trasplante de Riñón/patología , Obtención de Tejidos y Órganos , Cadáver , Carcinoma de Células Renales/patología , Femenino , Humanos , Incidencia , Neoplasias Renales/patología , Masculino , Persona de Mediana Edad , Trasplante de Neoplasias/estadística & datos numéricos
11.
J Clin Apher ; 7(4): 180-2, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1299655

RESUMEN

Six patients with prolonged acute courses of thrombotic microangiopathy are reviewed. These patients had in common courses of acute disease requiring plasma support for more than 3 months, with subsequent complete remission. Plasma support requirements may be prodigious, and the acute course may require more than 100 plasma exchanges before a stable remission is achieved. These patients appear to represent a subset of thrombotic microangiopathy distinct from the more common acute T.T.P. course, which resolves in 3-6 weeks, and the chronic relapsing pattern, which may have a short or prolonged acute course.


Asunto(s)
Síndrome Hemolítico-Urémico/terapia , Intercambio Plasmático , Púrpura Trombocitopénica Trombótica/terapia , Adulto , Niño , Femenino , Síndrome Hemolítico-Urémico/complicaciones , Humanos , Recién Nacido , Masculino , Persona de Mediana Edad , Púrpura Trombocitopénica Trombótica/complicaciones
12.
Theor Appl Genet ; 81(4): 445-60, 1991 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24221309

RESUMEN

In a twin study, we have shown that wild emmer wheat, Triticum dicoccoides, the progenitor of all cultivated wheats, harbours important genetic variation (Vg) in photosynthetic characteristics. This Vg resides within and between populations and ecogeographical regions in Israel, which is the center of origin and diversity of wild emmer wheat. Here we analyzed, by univariate and multivariate methods, the significant differentiation of variation in photosynthetic characteristics of 107 genotypes from 27 populations of wild emmer in Israel, distributed in three ecogeographical regions including central, xeric (northern cold and eastern warm) marginal, and mesic (western) marginal populations. The highest photosynthetic efficiency was displayed by populations of the xeric marginal region, but most variation for photosynthetic capacity occurs between accessions within ecogeographical regions and populations. Genotypes and populations of T. dicoccoides having high photosynthetic capacity can be identified by climatic factors and isozyme markers. The identification by genetic markers, if substantiated by testcrosses, can facilitate the maximization of conservation, in situ or ex situ, and utilization of these photosynthetic genetic resources for improvement of hexaploid wheat (T. aestivum).

13.
Photosynth Res ; 25(2): 119-28, 1990 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24420278

RESUMEN

Wild emmer wheat (Triticum dicoccoides Korn) has shown wide genetic diversity for disease resistance and morpho-physiological traits of economic importance. Our objectives were to test for genetic variation (VG) in photosynthetic characteristics residing within and between native populations sampled from three ecogeographical regions of Israel, and to identify potential sources of high photosynthetic efficiency for future wheat improvement. Accessions sampled in the center of wild emmer distribution (upper Jordan Valley) in a relatively narrow geographical range showed the greatest diversity in CO2-assimilation rate per unit leaf area (A) or per unit chlorophyll (A/Chl). Genetic variation was absent for internal CO2 concentration (Ci) and water-use efficiency (WUE) and generally lacking for stomatal conductance (gs). Leaf area, although quite variable, was not a significant cofactor in assessing genetic potential for photosynthesis. Accessions within a given population showed 10-times more variation in A and A/Chl than populations sampled from different locations in a region. Accessions with the highest photosynthetic efficiency were derived from upland steppic populations located in marginal habitats extending southward into Israel. Some accessions having high photosynthetic capacity (A=32 µmol m(-2) s(-1)) with no significant reduction in leaf size constitute a potentially valuable genetic resource yet untapped for genetic improvement of hexaploid (T. aestivum L.) wheat.

14.
Theor Appl Genet ; 78(3): 405-10, 1989 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24227249

RESUMEN

The presence of somaclonal variation is well documented in wheat, but information is needed which identifies point(s) during the tissue culture process at which variation is most likely induced. Field experiments were designed to partition the total somaclonal variation among three potential sources: single embryo-derived calli, regenerant (R0) plants of a common embryo-derived callus, and spike-derived lines of a common R0 plant. Three populations of winter wheat ('TAM 105', 'Vona', and 'KS75210') totaling 72 lines were evaluated in replicated drilled plots in the R2 and R3 generations. The principal source of variation was influenced by parent genotype. Considering all traits, somaclonal variation in the 'TAM 105' and 'Vona' populations was predominantly attributed to tillers from the same regenerant plant. This source, as well as the original R0 plant source, contributed to variation in the 'KS75210' population, depending on the trait measured. Embryos did not consistently provide a significant source of variation. The presence of somaclonal variation was not always associated with a downward shift in population mean compared to parental controls. Significant population increases were noted for spike density and biomass, and some lines showed significantly higher grain protein content without a yield reduction, but these responses were again genotype-specific.

15.
Photosynth Res ; 20(2): 105-18, 1989 May.
Artículo en Inglés | MEDLINE | ID: mdl-24425530

RESUMEN

Intra- and inter-specific variation in CO2 assimilation rate (A) in Triticum spp. is well documented for reproductive growth stages. Research was conducted to characterize early vegetative photosynthetic variation in a diverse set of cultivated hexaploid wheat (T. aestivum L.) germplasm and in wild tetraploid (T. dicoccoides Korn) and hexaploid x tetraploid populations. Choice of hexaploid genotypes was based on maximum genetic distance between cultivars within the HRW and SRW wheat classes of the USA. The tetraploid material was produced by hybridizing two accessions of T. dicoccoides previously shown to differ widely in A and A/Chl but with similar leaf morphology. Genetic variability in the HRW and SRW gene pools was attributed to more recently developed descendent lines and unrelated lines rather than parental lines. Phenotypic distributions for A, stomatal conductance (gs), and internal CO2 concentration (Ci) in the F2 tetraploid population were continuous and showed transgressive segregation, reflecting quantitative inheritance with intermediate heritability. Variability in A was not associated with chlorophyll content or CO2 supply to the mesophyll measured as Ci. Genetic variability in A was also observed in the interspecific backcross population, 2*TAM W-101/PI 428109, thereby providing a germplasm pool to select for high A while restoring the D genome of hexaploid wheat. These results suggest that genetic improvement of vegetative assimilation rate is feasible in hexaploid wheat via homologous transfer from an alien source.

16.
Fundam Appl Toxicol ; 11(3): 381-400, 1988 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3220214

RESUMEN

Substances known or suspected to cause subtle or transient anatomical alterations in renal development were administered prenatally or neonatally to rats in order to determine whether they are capable of altering renal functional development. Colchicine alters mitotic activity and cytoskeletal structure and is teratogenic in many species. Since the kidney of the newborn rat undergoes extensive cellular proliferation and nephron differentiation, it is possible that neonatal administration of colchicine may affect nephron development. Dinoseb and methyl salicylate have previously been reported to produce a high incidence of dilated renal pelvis in the term rat fetus. Colchicine was injected sc, at 75 micrograms/kg, to Postnatal Day (PD) 1 Sprague-Dawley rats. Dinoseb was administered ip to pregnant Sprague-Dawley rats on Gestation Days 10-12 at doses of 8 or 10.5 mg/kg/day, and methyl salicylate was administered ip at doses of 200, 250, or 300 mg/kg/day on Gestation Days 11-12. Renal function was examined in pups from immediately after birth through weaning. Maximal urine concentrating ability was measured after DDAVP (desmopressin acetate, a vasopressin analog) injection in suckling rats, and after 24 hr of water deprivation in weanlings. Proximal tubule transport was measured in renal cortical slices. Basal urinary parameters, including urine flow, osmolality, pH, and chloride content, were measured. Colchicine treatment had no effect on body weight or kidney weight. There was a significant decrease in maximal urine osmolality in PD 30 rats measured after 24 hr of water deprivation. The urine concentrating deficit detected in functionally mature PD 30 rats suggests that colchicine treatment during renal histogenesis causes a latent deficit in medullary function in the absence of any gross morphological effects. The 10.5 mg/kg/day dose of dinoseb caused a weight reduction in neonates which persisted after weaning. Urine volume after DDAVP challenge was increased over controls in both dose groups on PD 6, but maximal urine concentration was unaffected. On PD 14, maximal urine concentration after DDAVP injection was decreased in the 10.5 mg/kg/day group. By PD 30, urine concentrating ability was comparable to controls. Renal cortical slices from the 10.5 mg/kg/day dose group had an enhanced ability to accumulate organic anions on PD 3 and 31, but opposite effects were observed in the low-dose group. No other renal functional parameters were altered. Urine osmolality after DDAVP challenge was decreased over controls in the 250 mg/kg/day methyl salicylate group on PD 6, and urine volume was increased in this group after DDAVP injection on PD 14.(ABSTRACT TRUNCATED AT 400 WORDS)


Asunto(s)
2,4-Dinitrofenol/análogos & derivados , Colchicina/toxicidad , Dinitrofenoles/toxicidad , Herbicidas/toxicidad , Enfermedades Renales/inducido químicamente , Salicilatos/toxicidad , Teratógenos , Animales , Animales Lactantes , Desamino Arginina Vasopresina/toxicidad , Femenino , Feto/efectos de los fármacos , Corteza Renal/metabolismo , Enfermedades Renales/orina , Pruebas de Función Renal , Embarazo , Efectos Tardíos de la Exposición Prenatal , Ratas , Ratas Endogámicas
17.
Fundam Appl Toxicol ; 11(3): 401-15, 1988 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3220215

RESUMEN

Nitrofen and ethylenethiourea (ETU), agents known to prenatally induce hydronephrosis in rats, were assessed for their effects on postnatal renal functional maturation. Both were given by gavage to pregnant Sprague-Dawley rats on Gestation Day 11. Nitrofen was given at concentrations of 50 or 100 mg/kg, and ETU at 20, 40, or 60 mg/kg. Renal function was examined in the offspring from birth until after weaning, the period of renal functional maturation in the rat. Maximal urine concentrating ability was measured after DDAVP (desmopressin acetate, a vasopressin analog) challenge or water deprivation. Proximal tubule transport was measured in renal cortical slices. Various urinary parameters were measured. Both prenatal nitrofen and ETU exposure caused a large number of neonatal deaths at the high dose, and hydronephrosis was observed. The severity of the lesion increased with age. Hydronephrotic animals were deficient in urine concentrating ability, which became more pronounced after weaning. A few other urinary parameters were altered, but cortical function appeared to be unaffected. Rats prenatally exposed to nitrofen, but with apparently normal kidneys, were significantly compromised in their ability to produce a concentrated urine in response to DDAVP challenge, on Postnatal Days (PDs) 6 and 14. By PD 30, they were not different from controls in urine concentrating response. Rats prenatally exposed to the higher doses of ETU, but with grossly normal kidneys, had significantly decreased plasma clearances of certain electrolytes early in life, but by PD 27, they were not different from controls. Proximal tubule transport of PAH was increased on PD 7 in ETU-exposed pups, but this effect did not persist.


Asunto(s)
Etilenotiourea/toxicidad , Herbicidas/toxicidad , Imidazoles/toxicidad , Enfermedades Renales/inducido químicamente , Éteres Fenílicos/toxicidad , Teratógenos , Animales , Animales Recién Nacidos/fisiología , Desamino Arginina Vasopresina/toxicidad , Femenino , Edad Gestacional , Hidronefrosis/inducido químicamente , Hidronefrosis/orina , Capacidad de Concentración Renal , Enfermedades Renales/fisiopatología , Enfermedades Renales/orina , Pruebas de Función Renal , Túbulos Renales Proximales/metabolismo , Embarazo , Ratas , Ratas Endogámicas , Sodio/sangre , Sodio/orina
18.
Teratology ; 35(2): 239-45, 1987 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-3603406

RESUMEN

We have demonstrated that ethylenethiourea (ETU) is a potent teratogen to the rat embryo developing in vitro. Sprague Dawley rat embryos were explanted on gestation day 10 and cultured for 48 hours in the presence of 40-200 micrograms/ml ETU. This resulted in a dose-related inhibition of growth and differentiation as assessed by crown-rump length, protein and DNA content, and somite number and in an increase in the frequency of abnormalities. A variety of anomalies was produced, including fluid accumulation in the brain (hydrocephalus), decreased mandibular size, decreased telencephalon size, abnormal dorsiflexion, as well as subectodermal blisters on the tail and limb buds and maxilla. Frank malformations have been observed at these same sites--hydrocephalus, brachygnathia, kyphosis, limb and tail defects, cleft palate--in the term fetus in vivo. The presence of abnormal fluid accumulation in the embryos--distended neural tube and subectodermal blisters--suggesting that the osmotic environment of the embryo had been altered by ETU exposure. Osmolality of the exocoelomic fluid (ECF) surrounding the embryo was measured after 48 hours of exposure to a concentration of ETU that caused nearly a 100% incidence of subectodermal blisters. ECF osmolality was found to be significantly lower than that of control embryos. Lowered osmolality would cause water to move out of the ECF, presumably causing the observed fluid accumulation in the embryo. It is speculated that altered osmotic balance and localized edema in the embryo are contributory steps in the formation of defects after ETU exposure.


Asunto(s)
Anomalías Inducidas por Medicamentos/etiología , Etilenotiourea/toxicidad , Imidazoles/toxicidad , Teratógenos , Animales , Ectogénesis , Edema/inducido químicamente , Espacio Extracelular/fisiología , Femenino , Técnicas In Vitro , Embarazo , Ratas , Equilibrio Hidroelectrolítico/efectos de los fármacos
19.
Teratog Carcinog Mutagen ; 7(4): 341-6, 1987.
Artículo en Inglés | MEDLINE | ID: mdl-2888213

RESUMEN

Technical-grade dinocap, a complex-mixture fungicide, is teratogenic in the CD-1 mouse, causing cleft palate and otolith defects. In this study we compared the developmental toxicities of 2,4-dinitro-6-(1-methylheptyl)phenyl crotonate and 2,6-dinitro-4-(1-methylheptyl)phenyl crotonate, model isomers of the major active ingredients of technical dinocap, to the known teratogenicity of the technical compound. Individual isomers, both isomers combined, or technical dinocap were administered to pregnant mice on days 7-16 of gestation. Some dams were killed at term and litters were removed, dead fetuses and resorptions were counted, and live fetuses were weighed and preserved in Bodian's fixative for examination for cleft palate. Other treated dams were allowed to give birth: postnatal viability and growth, development of swimming behavior, and otolith formation were evaluated. As in previous studies, technical-grade dinocap caused cleft palate and weight deficits in fetuses at term and increased neonatal mortality and abnormal swimming behavior, torticollis, and deficient otolith formation in surviving pups. Neither of the purified isomers exhibited any developmental toxicity when administered under identical conditions. Thus, it is concluded that these isomers are not the active teratogenic component(s) in technical-grade dinocap.


Asunto(s)
Dinitrobencenos/toxicidad , Insecticidas/toxicidad , Nitrobencenos/toxicidad , Teratógenos , Animales , Femenino , Muerte Fetal , Reabsorción del Feto , Isomerismo , Ratones , Actividad Motora/efectos de los fármacos , Membrana Otolítica/anomalías , Embarazo , Natación , Tortícolis/inducido químicamente
20.
Teratog Carcinog Mutagen ; 6(5): 375-81, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-2878503

RESUMEN

The teratogenic potential of the fungicide dinocap was evaluated in CD-1 mice. Pregnant mice were dosed by intubation with dinocap in corn oil on gestation days 7-16. Doses used were 0, 5, 10, 20, 40, 80, and 120 mg/kg/day, based on day 6 weight. Dams were killed on day 18, at which time fetuses were counted, weighed, and preserved for necropsy or skeletal examination. The highest dose killed 80% of the dams dosed, while 29% of the dams in the 80 mg/kg group died during dosing. There was no dose-related maternal mortality at lower doses. Net maternal weight gain was affected only at 80 mg/kg/day. There were no live fetuses at 120 mg/kg/day. The number of live fetuses per litter was decreased and resorptions increased at 80 mg/kg. Dose-related decreases in gravid uterus weight and fetal weight were significant at all doses of dinocap. Cleft palate was found in fetuses at 5(1/234; 0.4%), 20(46/195; 23.6%), 40(140/185; 75.5%), and 80(63/85; 74.1%) mg/kg/day. There was a dose-related increase in supernumerary ribs and a low frequency of exencephaly and umbilical hernia at high doses. This study shows that dinocap is teratogenic in the CD-1 mouse at doses well below those causing maternal toxicity.


Asunto(s)
Dinitrobencenos/toxicidad , Fungicidas Industriales/toxicidad , Nitrobencenos/toxicidad , Teratógenos , Animales , Peso Corporal/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Femenino , Retardo del Crecimiento Fetal/inducido químicamente , Fungicidas Industriales/administración & dosificación , Ratones , Embarazo
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