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1.
Gen Comp Endocrinol ; 180: 48-55, 2013 Jan 01.
Article in English | MEDLINE | ID: mdl-23174697

ABSTRACT

The Eastern Box Turtle (Terrapene carolina carolina) is a widespread species that has recently experienced precipitous declines throughout its range. Although many studies have documented aspects of reproduction in box turtles, reproductive physiology of free-ranging animals is unknown and can be crucial in this species' recovery. Over a two-year period, we measured reproductive parameters, (vitellogenin [Vtg], estradiol-17ß [E2], and total testosterone [TT]), in plasma of 116 free-ranging Eastern Box Turtles across their active season. We found similar seasonal variations of Vtg and E2 within females. Mid-season, females showed a sharp peak in E2 that correlates with the putative beginning of the ovarian cycle. Individual females lacking these expected peaks of both Vtg and E2 suggest that some female T. c. carolina may not reproduce annually. Females typically expressed undetectable levels of TT, yet there was a small peak in TT early in the active season. Male Eastern Box Turtles exhibited a dual peak in TT. Elevated TT in males was significantly associated with observed sexual behaviors and smaller home ranges. Body condition had no effect on the concentration of TT or E2 in either sex. This is the first study to (1) document Vtg and sex steroid hormones in free-ranging animals of this genus, and (2) relate those metrics to individuals, the population, the purported annual cycle, and to other chelonian species.


Subject(s)
Gonadal Steroid Hormones/blood , Seasons , Vitellogenins/blood , Animals , Estradiol/blood , Female , Male , Testosterone/blood , Turtles
2.
J Wildl Dis ; 49(4): 996-9, 2013 Oct.
Article in English | MEDLINE | ID: mdl-24502728

ABSTRACT

The eastern snapping turtle (Chelydra serpentina) is widely distributed throughout the eastern and central US and is a useful model organism to study land-use impacts on water quality. We compared the reproductive condition of turtles from a pond impacted by runoff from land applied with animal manure from a concentrated animal feeding operation (CAFO) relative to animals from a control pond. Turtles from the CAFO site were heavier and had higher plasma concentrations of vitellogenin (VTG, mean ± SE; females; 859 ± 115 vs. 401 ± 127 ng/mL from controls) and testosterone (T, males; 39 ± 7.0 vs. 3.8 ± 6.9 ng/mL from controls). No VTG was detected in males. Body mass was positively correlated with VTG and T. Our results suggest that nutrient pollution of the CAFO pond indirectly resulted in higher plasma VTG in females and T in males because of an increase in body mass. The population-level consequences of these effects are not clear, but could result in females producing larger clutches.


Subject(s)
Reproduction/drug effects , Turtles/physiology , Water Pollutants/toxicity , Animal Husbandry , Animals , Environmental Monitoring , Female , Male , Manure
3.
Fish Physiol Biochem ; 38(2): 319-27, 2012 Apr.
Article in English | MEDLINE | ID: mdl-21647598

ABSTRACT

Short-term starvation has been linked to in vivo protein degradation in liver of rainbow trout (Oncorhynchus mykiss). However, it is unclear whether this proposed increase in protein degradation is followed by programmed cell death (apoptosis) in liver of starved trout. A preliminary study in our laboratory revealed an isoform of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) protein that increased 4.5-fold in liver of starved trout. GAPDH is a glycolytic enzyme involved in other cellular functions, including apoptosis. Increased intracellular nitric oxide (NO) promotes nuclear translocation of GAPDH that is associated with increased apoptosis in mammals. If GAPDH protein is associated with apoptosis in rainbow trout, it could potentially be used as a biomarker of cellular stress in liver of teleost fish species. The purpose of this study was to determine whether increased GAPDH protein expression in liver of starved rainbow trout is associated with NO-induced apoptosis. Targeted proteomic analysis using multiple reaction monitoring (MRM) was used to determine the level of GAPDH in nuclear and cytoplasmic fractions and inducible nitric oxide synthase (iNOS) in cell lysates. Dot blot and DNA fragmentation analyses were conducted to evaluate protein S-nitrosylation and apoptosis, respectively. Results showed that cytoplasmic GAPDH was 3.4-fold higher in liver of starved versus fed rainbow trout but could not be detected in nuclear fractions. Starvation significantly reduced hepato-somatic index but had no effect on iNOS protein expression, protein S-nitrosylation, or apoptosis. Our results indicate that starvation promoted significant reduction in liver mass that was not associated with increased apoptosis or NO-induced stress and that greater GAPDH concentration in liver of starved rainbow trout was located primarily in the cytoplasm.


Subject(s)
Apoptosis , Glyceraldehyde-3-Phosphate Dehydrogenases/metabolism , Liver/metabolism , Nitric Oxide/metabolism , Oncorhynchus mykiss/metabolism , Starvation/enzymology , Animals , Fish Proteins/metabolism , Isoenzymes/metabolism , Liver/physiopathology , Nitric Oxide Synthase Type II/metabolism , Tandem Mass Spectrometry
4.
J Wildl Dis ; 47(4): 836-48, 2011 Oct.
Article in English | MEDLINE | ID: mdl-22102654

ABSTRACT

The eastern hellbender (Cryptobranchus alleganiensis alleganiensis) has experienced precipitous population declines throughout its range. Numerous factors are speculated to be involved, but no empirical evidence has been presented for any. We implemented a population-wide health assessment in Indiana, USA, examining both the physical well-being of individuals and the quality of their habitat. Physicochemical parameters were analyzed directly in the field and later in the laboratory, when appropriate. Samples were collected June 2008-October 2008 and June 2009-September 2009 for reproductive analysis, blood screening, and disease prevalence. Of 27 chemicals screened in water samples, three were found in the study site, including atrazine. Atrazine was found at levels reported to cause reproductive problems in other amphibians. Vitellogenin was detected only in females and proved a reliable indicator of sex. Sperm parameters were generally of high quality and similar to other populations. Most plasma parameters were similar between sexes, although there were significant differences in calcium and potassium concentrations. Abnormalities were common, occurring in 68% of individuals. No hemoparasites were found, but amphibian chytrid fungus (Batrachochytrium dendrobatidis) was detected on one individual. Our findings establish a baseline for hematology and water-quality parameters that can be used as a model for evaluating population health throughout the hellbender range.


Subject(s)
Ecosystem , Health Status , Urodela/physiology , Animals , Female , Indiana , Male , Population Dynamics , Reference Values , Water Pollutants, Chemical/analysis , Water Pollutants, Chemical/metabolism
5.
J Pediatr Adolesc Gynecol ; 24(1): 2-9, 2011 Feb.
Article in English | MEDLINE | ID: mdl-20869281

ABSTRACT

OBJECTIVE: The purpose of this review is to summarize the findings of randomized controlled trials assessing the advance provision of emergency contraception (EC) to women 24 years of age or younger. DESIGN: We conducted a comprehensive search of the PubMed database from 1950 to November 11, 2009. This review includes seven studies that randomly assigned women aged 24 and younger to advance provision of EC or a control group. RESULTS: All studies reviewed found that women assigned to advance provision were more likely to use EC, though not all reached statistical significance. Furthermore, studies assessing time to EC use (N = 4) found that those with advance provision used EC sooner following intercourse. Most studies found that women assigned to advance provision of EC did not engage in more sexual risk taking behaviors (assessed by reported number of sexual partners, number of episodes of unprotected intercourse, and acquisition of sexually transmitted infections) or switch to less reliable contraceptive methods. Despite increased use and decreased time to use, women who were provided EC in advance did not report significantly lower pregnancy rates. CONCLUSIONS: The existing literature suggests that among women 24 years of age or younger, advance provision has a positive impact on use and time to use of EC. Most findings indicate that increased use of EC does not have significant negative effects for ongoing contraceptive use or sexual risk taking behaviors. Despite increased use, advanced provision of EC has not been associated with a significant corresponding decrease in pregnancy.


Subject(s)
Contraceptives, Postcoital , Adolescent , Contraceptives, Postcoital/administration & dosage , Female , Humans , Pregnancy , Sexual Behavior , Young Adult
6.
Am J Clin Nutr ; 92(4): 864-71, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20739422

ABSTRACT

BACKGROUND: Poor maternal folate status has been associated with an increased risk of preterm birth. However, major gaps remain in our understanding of how individual folate species relate to preterm birth. OBJECTIVE: Our objective was to assess the association between maternal folate status as measured by 5-methyltetrahydrofolate (5MeTHF), 5-formyltetrahydrofolate (5FoTHF), and folic acid concentrations, which are the 3 primary folate species in serum, and the risk of preterm birth and spontaneous preterm birth (sPTB). DESIGN: A cohort of 313 pregnant women who received care at resident antepartum clinics at Magee-Womens Hospital (Pittsburgh, PA) (2003-2007) was enrolled at <16 wk gestation. We analyzed nonfasting blood samples that were drawn from subjects at enrollment for the 3 folate species by using HPLC-tandem mass spectrometry. RESULTS: Serum 5MeTHF and 5FoTHF concentrations comprised 65% and 33% of total folate concentrations, respectively. In confounder-adjusted, multivariable, log-binomial regression models, 1-SD increases in serum total folate and serum 5MeTHF concentrations were associated with significant reductions in the risk of sPTB (P < 0.05). There was a significant interaction between serum 5MeTHF and 5FoTHF concentrations and risk of preterm birth (P = 0.01). When serum 5MeTHF concentrations were low, there was a positive linear relation between 5FoTHF and risk of preterm birth. When 5MeTHF concentrations were high, there was a strong negative relation between 5FoTHF and preterm birth. CONCLUSIONS: Our results imply that the relative concentrations of folate species may be more critical than total folate in preventing preterm birth. An improved understanding of folate metabolism during pregnancy may lead to targeted intervention strategies that decrease the rate of preterm birth.


Subject(s)
Folic Acid/blood , Infant, Premature/physiology , Black People , Chromatography, High Pressure Liquid , Female , Folic Acid/metabolism , Humans , Infant, Newborn , Leucovorin/blood , Pennsylvania , Pregnancy , Pregnancy Trimester, First , Pregnancy Trimester, Second , Prospective Studies , Risk Factors , Surveys and Questionnaires , Tetrahydrofolates/blood , White People
7.
Ann Emerg Med ; 56(2): 126-34, 2010 Aug.
Article in English | MEDLINE | ID: mdl-20074835

ABSTRACT

STUDY OBJECTIVE: Computed tomography (CT) is increasingly used for emergency department (ED) patients with abdominal tenderness. CT-related radiation contributes to 2% of US cancers. We hypothesized that in the ED patient with nontraumatic abdominal tenderness, the tender region accurately delineates acute pathology. z axis-restricted CT guided by this region could detect pathology while reducing radiation dose. METHODS: This was a prospective double-blinded observational trial with informed consent and was institutional review board-approved and registered with ClinicalTrials.gov. A convenience sample of ED patients undergoing abdominal CT was recruited, excluding pregnant women, patients with altered mental status or abdominal sensation, preverbal children, and patients with abdominal trauma or surgery in the previous month. Before standard CT, physicians demarcated the tender region with labels invisible to radiologists on abdominal windows. Radiologists blinded to the tender region recorded cephalad-caudad limits of pathology on CT. Personnel blinded to pathology location recorded label positions on lung windows. Two hypothetical CT strategies were then explored: CT restricted to the tender region and CT from the cephalad skin marker to the lower caudad limit of the usual CT. The percentage of the pathologic region contained within the extent of the 2 hypothetical z axis restricted CTs was calculated. z axis reduction, which is linearly related to radiation reduction, from the restricted CTs was determined. RESULTS: One hundred two subjects were enrolled, 93 with complete data for analysis. Fifty-one subjects had acute pathology on CT. CT limited to the tender region would reduce z axis (radiation exposure) by 69% (95% confidence interval [CI] 60% to 78%). All acute pathology was included within these boundaries in 17 of the 51 abnormal cases (33%; 95% CI 22% to 47%). CT from the cephalad marker through the caudad abdomen and pelvis would reduce z axis (radiation exposure) by 38% (95% CI 29% to 48%). All acute pathology was included within these boundaries in 36 of 51 abnormal cases (71%; 95% CI 57% to 81%). With both strategies 1 and 2, the pathologic region was at least partially included within the CT region in the majority of cases (84% and 92%, respectively). CONCLUSION: CT with z axis restriction based on abdominal tenderness could reduce radiation exposure but with a potentially unacceptably high rate of misdiagnosis, using our current methods. Further prospective study may be warranted to determine the diagnostic utility of partially visualized pathology.


Subject(s)
Abdominal Pain/diagnostic imaging , Pelvis/diagnostic imaging , Radiation Dosage , Tomography, X-Ray Computed/methods , Adolescent , Adult , Aged , Aged, 80 and over , Child , Double-Blind Method , Emergency Service, Hospital , Female , Humans , Male , Middle Aged , Outcome Assessment, Health Care , Prospective Studies , Sensitivity and Specificity , Tomography, X-Ray Computed/standards , Young Adult
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