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1.
Hum Reprod ; 36(8): 2073-2082, 2021 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-34097020

RESUMO

STUDY QUESTION: What is the nuclear heterogeneity of high-density purified human spermatozoa typically used for IVF purposes. SUMMARY ANSWER: The data show that while density gradient separation has improved the overall sperm population, there is still a large degree of nuclear heterogeneity within these cells. WHAT IS KNOWN ALREADY: Chromomycin A3 (CMA3) is an important DNA binding fluorochrome for the assessment of male-factor fertility. It is typically used to predict IVF outcomes on entire sperm ejaculates with very high receiver operating characteristic. Here we used CMA3 to characterise typical populations of human spermatozoa that would be used for IVF purposes after density gradient separation. STUDY DESIGN, SIZE, DURATION: We compared the intensity of CMA3 binding within high-dense sperm populations obtained from men. Binding heterogeneity was confirmed through fluorescence microscopy and FACS analysis independently. We also looked at CMA3 staining directly with head morphology in this sperm population. Finally, we looked at electron micrographs of nuclear heterogeneity (vacuoles, chromatin compaction) of spermatozoa following density gradient sorting of CMA3-stained cells. PARTICIPANTS/MATERIALS, SETTING, METHODS: We used sperm donors who had fathered one or more children. Semen was collected after 2 days abstinence and purified over Percoll gradients. Only the high-quality spermatozoa, the same used for assisted conception, were then used. Cells were stained with CMA3 and sorted using FACS. Following this, electron micrographs were used to assess nuclear heterogeneity of CMA3-dependent sorted spermatozoa. MAIN RESULTS AND THE ROLE OF CHANCE: CMA3 staining occurs within morphologically normal as well as abnormal spermatozoa. High-intensity CMA3-stained sperm possessed large vacuoles that were not seen in the low-CMA3 population. In addition, the high-CMA3 stained cells possess higher amounts of nuclear granulation. LIMITATIONS, REASONS FOR CAUTION: The present study only describes the issues within the chromatin of these cells and does not suggest an alternate selection technique. WIDER IMPLICATIONS OF THE FINDINGS: CMA3 is one of the better reported prognostic assays in predicting pregnancy outcomes, especially in cases where the male is at fault. However, it is clear that even in fractionated populations of human spermatozoa, there are sperm cells that are morphologically normal yet possess high levels of CMA3 staining and chromatin granulation. The implication of this is that the embryologist, whom selects on the basis of sperm morphology, may choose a cell with poor chromatin, which may lead to poor embryo outcomes. STUDY FUNDING/COMPETING INTEREST(S): The project was funded by the National Health and Medical Research council, APP1118943. The authors have no conflict of interest to declare. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Infertilidade Masculina , Espermatozoides , Criança , Cromomicina A3 , Fertilização , Humanos , Masculino , Sêmen
2.
Ecotoxicology ; 29(7): 1106, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32430604

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

3.
Environ Toxicol Chem ; 34(10): 2250-62, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25929226

RESUMO

Hyalella azteca are epibenthic invertebrates that are widely used for toxicity studies. They are reported to be more sensitive to pyrethroid insecticides than most other test species, which has prompted considerable use of this species in toxicity testing of ambient surface waters where the presence of pyrethroids is suspected. However, resident H. azteca have been found in some ambient water bodies reported to contain surface water and/or sediment pyrethroid concentrations that are toxic to laboratory reared H. azteca. This observation suggests differences in the sensitivities of laboratory reared and field populations of H. azteca to pyrethroids. The goal of the present study was to determine the sensitivities of laboratory reared and field populations of H. azteca to the pyrethroids bifenthrin and cypermethrin. Specimens of H. azteca were collected from resident populations at field sites that are subject to varied land-use activities as well as from laboratory populations. These organisms were exposed to bifenthrin- or cypermethrin-spiked water in 96-h water-only toxicity tests. The resulting data demonstrated that: 1) field-collected populations in urban and agricultural settings can be >2 orders of magnitude less sensitive to the pyrethroids than laboratory reared organisms; 2) field-collected organisms varied in their sensitivity (possibly based on land-use activities), with organisms collected from undeveloped sites exhibiting sensitivities similar to laboratory reared organisms; and 3) the sensitivity of field-collected "tolerant" organisms increased in subsequent generations reared under laboratory conditions. Potential mechanisms for these differences are discussed.


Assuntos
Anfípodes/efeitos dos fármacos , Inseticidas/toxicidade , Piretrinas/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Inseticidas/química , Laboratórios , Testes de Toxicidade Aguda , Poluentes Químicos da Água/química
4.
Ultrasound Obstet Gynecol ; 46(4): 419-23, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25678383

RESUMO

OBJECTIVE: To examine the effect of a combination of screening and treatment with low-dose aspirin on the prevalence of early-onset pre-eclampsia (PE). METHODS: This was a retrospective analysis of two consecutive cohorts of women screened for early PE. The first cohort was observed to determine whether algorithms developed to screen for PE at 11 to 13 + 6 weeks' gestation could be applied to our population. High-risk women in the second cohort were advised on their risk and offered aspirin (150 mg at night), with treatment starting immediately after screening. The prevalence of early PE and the proportion of women with PE delivering at 34-37 weeks' gestation were compared between the cohorts. RESULTS: In the observational and interventional cohorts, 3066 and 2717 women, respectively, were screened. There were 12 (0.4%) cases of early PE in the observational cohort and one (0.04%) in the interventional cohort (P < 0.01). Among all women with PE delivering before 37 weeks, 25 (0.83%) were in the observational cohort and 10 (0.37%) in the interventional cohort (P = 0.03). CONCLUSIONS: A strategy of first-trimester screening for early PE coupled with prescription of aspirin to the high-risk group appears to be effective in reducing the prevalence of early PE.


Assuntos
Aspirina/administração & dosagem , Inibidores da Agregação Plaquetária/administração & dosagem , Pré-Eclâmpsia/prevenção & controle , Adulto , Austrália/epidemiologia , Estudos de Coortes , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Pré-Eclâmpsia/diagnóstico , Pré-Eclâmpsia/diagnóstico por imagem , Pré-Eclâmpsia/epidemiologia , Valor Preditivo dos Testes , Gravidez , Resultado da Gravidez , Primeiro Trimestre da Gravidez , Estudos Retrospectivos , Fatores de Risco , Ultrassonografia Doppler de Pulso/métodos
5.
Pregnancy Hypertens ; 2(3): 179-80, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26105224

RESUMO

INTRODUCTION: Visualisation of the microcirculation through retinal imaging can provide information on the health of systemic vasculature. Characterisation of the retinal vasculature throughout pregnancy using retinal imaging is a novel approach to examine physiological changes to the cardiovascular system, and may be useful to predict early pathophysiological signs of adverse maternal outcomes. OBJECTIVES: To characterise the retinal vascular and blood pressure (BP) changes that occur throughout a healthy pregnancy. METHODS: Data was collected from women recruited at 13±2 weeks of gestation from Royal Prince Alfred Hospital, a major tertiary referral hospital in Sydney, Australia. Retinal images centred on the optic disc and BP readings were collected throughout pregnancy. Postnatal data was collected from medical records, and women with hypertensive disorders of pregnancy and gestational diabetes mellitus were excluded. This left a final group of 19 women. Retinal images from 13±2, 19±2, 29±2 and 38±2 weeks gestation were graded using semi-automated retinal vascular calibre measurement (IVAN) software and the central retinal arteriolar equivalent (CRAE), and central retinal venular equivalent (CRVE). BP data was collected at the same time points as the retinal images. Analysis of data was performed using paired t-tests and repeated measures analysis of variance (ANOVA). Women with missing data points were excluded from the analysis at the relevant time points. RESULTS: Over the course of pregnancy, there was a significant dilatation of retinal arterioles between 13±2 and 19±2weeks (from 166.4 to 172.7µm, SE: 3.7µm, n=19, p=0.01), corresponding to a significant fall in diastolic BP during this time (from 64.6 to 60.2mmHg, SE: 1.5mmHg, p=0.01). No significant changes in venular diameter or systolic BP were noted. Between 19±2 and 29±2weeks (n=4), no significant changes to retinal arteriolar or venular diameter were seen although there were significant increases in both systolic and diastolic BP (SBP: from 100.3 to 109.9mmHg, SE: 1.9mmHg, p=0.01; DBP: from 59.3 to 64.6mmHg, SE: 6.9mmHg, p=0.01). Between 29±2 and 38±2weeks (n=3), no significant changes in retinal arteriolar, and venular diameter or BP were observed. CONCLUSION: An increase in retinal arteriolar diameter between 13±2 and 19±2 weeks gestation was observed, which corresponded to a decrease in both systolic and diastolic BP. However, between 19±2 and 29±2 weeks there was no change in vasculature, even though there was a significant increase in BP. By characterising the changes to retinal vessels that occur throughout a healthy pregnancy, we can further our understanding of the response of the systemic vasculature to pregnancy, which may provide clues to early vascular disease of pregnancies.

6.
Pregnancy Hypertens ; 2(3): 182-3, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26105230

RESUMO

INTRODUCTION: Hypertensive disorders of pregnancy (HDP) are characterised by vascular dysfunction. Retinal vascular imaging is a novel, non-invasive way to characterise early microvascular changes in pregnancy, and as a result has the potential to be used to predict the onset of HDP. OBJECTIVES: To characterise retinal vascular changes that occur in HDP, and compare these changes to those in healthy pregnancies. METHODS: Women were recruited at 13±2 weeks of gestation from Royal Prince Alfred Hospital, a major metropolitan tertiary referral hospital in Sydney, Australia. Retinal images centred on the optic disc and blood pressure (BP) readings were collected at 13±2, 19±2, 29±2 and 38±2 weeks gestation. Retinal images were graded using semi-automated retinal vascular calibre measurement software (IVAN) and the central retinal arteriolar equivalent (CRAE) and central retinal venular equivalent (CRVE) were calculated. Within and between subject repeat measures analysis was performed on images from each trimester, using paired t-tests and repeated measures analysis of variance (ANOVA). Multiple linear regressions were used to model the average arteriole diameter adjusted for age, tobacco consumption and body mass index (BMI). All tests were two-sided using a 5% level of significance. A clinical diagnosis of HDP was obtained from postnatal medical record data. Women with missing data points were excluded from the analysis at that time point. RESULTS: Of the 39 women included in the study, 6 (15%) were diagnosed with HDP. In the HDP cohort, repeated measures ANOVA revealed no significant changes in arteriolar or venular diameter measurements throughout pregnancy. Paired t-tests indicated no significant differences in any of the outcome measures between HDP and healthy pregnancies at 13±2 (n=36) and 19±2 (n=39)weeks. At 29±2weeks (n=39), there was a significantly smaller venular diameter in HDP pregnancies (220.4±6.9µm vs 239.1± 5.4µm in healthy pregnancies, p=0.03). At 38±2weeks (n=39), arteriolar diameter was significantly smaller in HDP pregnancies (148.6±6.0µm vs 164.1±4.6µm in healthy pregnancies, p=0.04). Similar results persisted following adjustments for cardiovascular risk factors (age, tobacco use and BMI). CONCLUSION: Significant differences in the retinal vasculature develop in HDP as compared to healthy pregnancies. These differences appear at29±2weeks gestation and persist throughout the rest of the pregnancy. Retinal vascular imaging is a promising tool for the detection of the early microvascular changes in HDP, prior to diagnosis.

7.
Pregnancy Hypertens ; 2(3): 210, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26105275

RESUMO

INTRODUCTION: Preeclampsia is a disorder related to an imbalance in the angiogenesis axis manifesting as endothelial dysfunction. Animal and human studies have shown that sFLT-1 (soluble fms like tyrosine kinase 1) is increased and PlGF (placental growth factor) reduced during the disease state. There are a paucity of studies investigating the clinical significance of normalising angiogenic axis. OBJECTIVES: To use a non-human primate uteroplacental ischemic (UPI) model of preeclampsia to assess if reversing the angiogenic imbalance, by increasing circulating PlGF, is able to ameliorate the hypertension and proteinuria. METHODS: Hypertensive proteinuria was induced in a non-human primate (Papio hamadryas) by ligation of a unilateral uterine artery at 130days of an 182day pregnancy. After two weeks of UPI, PlGF was administered by subcutaneous injection (100mg/kg/day) for 5 days (n=3) or normal saline in an equivalent volume (n=3). Blood pressure was monitored via intra-arterial radiotelemetry, sFLT-1 measured via ELISA and spot urinary protein:creatinine ratios were measured to monitor proteinuria. Data was analysed using SPSS by t-tests and analysis of repeated measures. Significance was set at p<0.05 and data expressed as the mean ±SEM. RESULTS: After two weeks of UPI both groups demonstrated a significant elevation in blood pressure, proteinuria (p<0.05) and sFLT-1 (p<0.001). The systolic BP increased by 12.4±2.3mmHg and 11.7±2.9mmHg in the PlGF and control groups respectively compared to baseline (p<0.005). After PlGF administration, there was a significant reduction in blood pressure in the treated group (-5.2s±0.8mmHg) compared to the increase in BP in the control group (+6.5±3mmHg). Proteinuria also reduced in the treated group from 112±51mg/mmol to 38±12mg/mmol whilst proteinuria in the control group was unchanged. The total circulating sFLT-1 was not significantly affected by the administration of PlGF after 5days. Although this study was not designed to assess fetal safety or outcomes, there was no adverse fetal outcome attributable to the administration of the PlGF. CONCLUSION: Administration of PlGF resulted in a reduction in BP and proteinuria without significantly affecting total sFLT-1 levels. Correcting the angiogenic axis imbalance may improve the clinical parameters in a non-human primate animal model of preeclampsia.

8.
Pregnancy Hypertens ; 2(3): 260, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26105356

RESUMO

INTRODUCTION: Hypertensive disorders of pregnancy (HDP) remain a leading cause of maternal and perinatal morbidity and mortality worldwide. In Australia approximately 10% of all pregnancies are affected by HDP. There is growing evidence that endothelial damage caused by HDP remains after pregnancy and has long term consequences on maternal health. OBJECTIVES: The aim of our research was to determine the association between HDP and risk of having high blood pressure in later life. METHODS: Self-reported data regarding a physician's diagnosis of HDP and of high blood pressure later in life were obtained from women recruited from the 45 and Up Study, Australia. Relative risks (converted from odds ratios) and 99% confidence intervals were estimated using logistic regression, adjusting for demographic and lifestyle characteristics. RESULTS: A total of 82,164 women were included in the study, of which 9,845 reported having HDP. Women who had HDP had a significantly increased risk of having high blood pressure later in life compared to women who did not have HDP (adjusted relative risk of 2.05, 99% CI 1.99-2.11, p<0.001). The results showed that women who had HDP develop high blood pressure 6.3 years (99% CI 5.85-6.66, p<0.001) earlier compared to women without HDP. CONCLUSION: Women who have HDP are at a greater risk of future onset of high blood pressure compared to women who have a healthy pregnancy. Women with HDP should be monitored closely in the years following pregnancy for early identification and intervention of high blood pressure.

9.
Pregnancy Hypertens ; 2(3): 260, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26105358

RESUMO

INTRODUCTION: Cardiovascular disease (CVD) is a leading cause of mortality worldwide in women aged >54years. There is a strong association between HDP and the development of hypertension in later life. OBJECTIVES: To ascertain the current health profile of some of the women who were diagnosed with a HDP and participated in a trial during the time period of 1980-1989 and to examine the association between the two. METHODS: Women who delivered at a major teaching hospital during the designated time period and who were enrolled at that time in trials examining HDP treatments and outcomes were invited to participate in a health status evaluation. Their medical histories, time sequenced blood pressure readings, urinalysis, BMI and pulse wave analysis were compared using standard statistical techniques of Chi-square analysis and Student's t-tests obtained from IBM SPSS v.19™. RESULTS: Thirty-nine women from the trials were available for follow-up. Of these women, 85% had current CVD, of which 88% had hypertension, 59% hypercholesterolaemia and 3% had experienced a CVA. Compared to the general female population of 22% for CVD this equates to a RR of 7.2 (CI 95% 3.042-15.13). CONCLUSION: HDP is associated with an increased risk of CVD compared to the general female population. Women who experience HDP in their pregnancy should be monitored regularly due to an increased risk of CVD and potentially early onset of the disease.

10.
Pregnancy Hypertens ; 2(3): 295, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26105424

RESUMO

INTRODUCTION: Hypertensive Disorders of Pregnancy (HDP) remain a leading cause of maternal morbidity and mortality worldwide affecting up to 10% of all pregnancies. Previous works inform that long term morbidity includes cardiovascular disease, including ischaemic heart disease, stroke and hypertension. The extent of long term mortality amongst women distant from the primary pregnancy event is not known. OBJECTIVES: To determine mortality rates and cause of death for women who had hypertension during pregnancy between the years 1980-86. METHODS: Women who had hypertension during pregnancy were identified via by ICD-9 coding. From record examination, there was an existing cohort of women who participated in clinical trials at Royal Prince Alfred Hospital in the 1980's. These trials included placebo controlled for blood pressure in pregnancy. The deaths among this cohort were identified by the NSW Registry of Birth Deaths and Marriages. The causes of death were verified from the International Classification of Diseases versions depending upon the year of death. RESULTS: There were a total of 332 women identified as participating in the various trials between the years 1980-86. Of these, there were 17 deaths reported by 2011. This gives an overall mortality rate of 5.1%. Five of these deaths were due to CVD. This equates to an RR of 44.6 (CI 95% 17.43-112.56). CONCLUSION: Women with hypertensive disorders in pregnancy have a higher mortality rate compared to the general female population. Further research is required to determine the relationship between HDP and future hypertension and whether the type of treatment and management women receive with HDP effects their risk of future long term health outcomes.

11.
Ecotoxicology ; 20(8): 2079-89, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21789673

RESUMO

Previous studies have indicated that tire tread particles are toxic to aquatic species, but few studies have evaluated the toxicity of such particles using sediment, the likely reservoir of tire wear particles in the environment. In this study, the acute toxicity of tire and road wear particles (TRWP) was assessed in Pseudokirchneriella subcapita, Daphnia magna, and Pimephales promelas using a sediment elutriate (100, 500, 1000 or 10000 mg/l TRWP). Under standard test temperature conditions, no concentration response was observed and EC/LC(50) values were greater than 10,000 mg/l. Additional tests using D. magna were performed both with and without sediment in elutriates collected under heated conditions designed to promote the release of chemicals from the rubber matrix to understand what environmental factors may influence the toxicity of TRWP. Toxicity was only observed for elutriates generated from TRWP leached under high-temperature conditions and the lowest EC/LC(50) value was 5,000 mg/l. In an effort to identify potential toxic chemical constituent(s) in the heated leachates, toxicity identification evaluation (TIE) studies and chemical analysis of the leachate were conducted. The TIE coupled with chemical analysis (liquid chromatography/mass spectrometry/mass spectrometry [LC/MS/MS] and inductively coupled plasma/mass spectrometry [ICP/MS]) of the leachate identified zinc and aniline as candidate toxicants. However, based on the high EC/LC(50) values and the limited conditions under which toxicity was observed, TRWP should be considered a low risk to aquatic ecosystems under acute exposure scenarios.


Assuntos
Cyprinidae , Daphnia/efeitos dos fármacos , Hyperotreti , Borracha/toxicidade , Poluentes da Água/toxicidade , Animais , Ecotoxicologia/métodos , Exposição Ambiental , Sedimentos Geológicos , Temperatura , Testes de Toxicidade Aguda
12.
Environ Toxicol Chem ; 29(2): 311-319, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20821449

RESUMO

The copper sensitivity of four saltwater invertebrates (the mussel Mytilus galloprovincialis, the oyster Crassostrea virginica, the sand dollar Dendraster excentricus, and the sea urchin Strongylocentrotus purpuratus) was determined experimentally using chronic-estimator embryo-larval test procedures. The effect of sample dissolved organic matter (DOM) content on Cu bioavailability was determined for these species using commonly prescribed test procedures. Comparisons were made among these test results and test results reported previously for two other invertebrate species: the mussel Mytilus edulis and the copepod Eurytemora affinis. All six species exhibited a direct and significant relationship between the sample dissolved organic carbon (DOC; a surrogate measure of DOM) and either the dissolved Cu median lethal concentration (LC50) values or median effect concentration (EC50) values. This relationship is significant even when the DOM has different quality as evidenced by molecular fluorescence spectroscopy. Once normalized for the effects of DOM, the Cu sensitivity of these species from least to most sensitive were E. affinis < D. excitricus < C. virginica approximately S. purpuratus approximately M. edulis approximately M. galloprovincialis. This ranking of species sensitivity differs from the saltwater species sensitivity distribution proposed in 2003 by the U.S. Environmental Protection Agency. These results support the need to account for factors that modify Cu bioavailability in future saltwater Cu criteria development efforts. More specifically, Cu saltwater species sensitivity distribution data will need to be normalized by factors affecting Cu bioavailability to assure that accurate and protective criteria are subsequently developed for saltwater species and their uses.


Assuntos
Cobre/toxicidade , Compostos Orgânicos/análise , Água do Mar/análise , Poluentes Químicos da Água/toxicidade , Animais , Disponibilidade Biológica , Bivalves , Cobre/farmacocinética , Ostreidae , Ouriços-do-Mar , Especificidade da Espécie , Poluentes Químicos da Água/análise
13.
Clin Exp Pharmacol Physiol ; 36(8): 839-42, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19215236

RESUMO

1. Increases in soluble fms-like tyrosine kinase 1 (sFlt-1) and soluble endoglin (sEng) contribute to the pathogenesis of pre-eclampsia. Soluble Flt-1 binds to circulating free vascular endothelial growth factor and placenta growth factor and this is associated with endothelial dysfunction. Soluble endoglin, a transforming growth factor (TGF)-beta coreceptor, was reported to synergize with sFlt-1 to amplify endothelial dysfunction by inhibiting TGF-beta1-mediated vasorelaxation. 2. The aim of the present study was to examine whether the antihypertensive drugs clonidine (0.08-1.3 microg/mL), diazoxide (25-300 microg/mL), frusemide (60-1000 microg/mL) and hydralazine (6.3-100 microg/mL) have any effect on placental production of sFlt-1 and sEng in placentas from normal and pre-eclamptic pregnancies. 3. Explants were taken from non-laboured term placentas of normal pregnancy (n = 5) and women with pre-eclampsia (n = 5). Villous explants were cultured with increasing doses of antihypertensive drugs. Placental sFlt-1 and sEng production was examined using ELISA. 4. Baseline sFlt-1 production was higher in placentas from women with pre-eclampsia than from normal pregnancy (4.5 +/- 1.4 vs 3.2 +/- 0.6 ng/mg of total protein, respectively; P < 0.001), as was sEng production (9.0 +/- 2.3 vs 4.1 +/- 0.6 ng/mg of total protein, respectively; P < 0.001). With the exception of frusemide, none of the antihypertensive drugs tested had any effect on sFlt-1 and sEng production from placental explants of normal pregnancy and women with pre-eclampsia. Increasing frusemide concentrations were correlated with increased sEng production in normal pregnancy (P < 0.005). 5. In conclusion, placental sFlt-1 and sEng production was higher in pre-eclampsia and antihypertensive drugs had no effect on placental production of sFlt-1 and sEng in vitro.


Assuntos
Antígenos CD/biossíntese , Anti-Hipertensivos/farmacologia , Placenta/efeitos dos fármacos , Pré-Eclâmpsia/metabolismo , Receptores de Superfície Celular/biossíntese , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/biossíntese , Adulto , Relação Dose-Resposta a Droga , Endoglina , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/enzimologia , Endotélio Vascular/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Idade Gestacional , Humanos , Técnicas In Vitro , Placenta/enzimologia , Placenta/metabolismo , Pré-Eclâmpsia/enzimologia , Gravidez , Solubilidade
14.
J Environ Qual ; 38(1): 238-47, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19141814

RESUMO

Addition of anionic polyacrylamide (PAM) to agricultural irrigation water can dramatically reduce erosion of soils. However, the toxicity of PAM to aquatic life, while often claimed to be low, has not been thoroughly evaluated. Five PAM formulations, including two oil-based products, one water-based product, one granular product and one tablet product, were evaluated for acute and/or chronic toxicity to five species commonly used for freshwater toxicity testing [Hyalella azteca (Saussure), Chironomus dilutus (Shobanov et al.), Ceriodaphnia dubia (Richard), Pimephales promelas (Rafinesque), and Selenastrum capricornutum (Printz)]. When applied as an oil-based product, acute toxicity was seen to four of the five species at concentrations less than the 10 mg/L that is often used for erosion control. Toxicity was diminished, but still remained, after passage of the irrigation water across an agricultural field, indicating a potential impact to nearby surface waters. Results from the non-oil-based products indicated minimal toxicity associated with PAM even at concentrations 10 times those used in agriculture when applied in the granular form, as a tablet, or in a water-based liquid. These data suggest that other agents in the oil-based products, such as surfactants or emulsifiers, rather than the PAM itself, contribute to the toxicity. Care is required in selecting an appropriate PAM formulation when the potential exists for entry of tailwater to nearby surface waters.


Assuntos
Resinas Acrílicas/toxicidade , Agroquímicos/toxicidade , Resinas Acrílicas/administração & dosagem , Agricultura , Agroquímicos/administração & dosagem , Anfípodes/efeitos dos fármacos , Animais , Chironomidae/efeitos dos fármacos , Clorófitas/efeitos dos fármacos , Cladocera/efeitos dos fármacos , Cyprinidae , Testes de Toxicidade
15.
Acta Biomater ; 4(5): 1187-97, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18434267

RESUMO

A novel scaffold fabrication method utilizing both polymer blend extrusion and gas foaming techniques to control pore size distribution is presented. Seventy-five per cent of all pores produced using polymer blend extrusion alone were less than 50microm. Introducing a gas technique provided better control of pore size distribution, expanding the range from 0-50 to 0-350microm. Varying sintering time, annealing temperature and foaming pressure also helped to reduce the percentage of pore sizes below 50microm. Scaffolds chosen for in vitro cellular studies had a pore size distribution of 0-300microm, average pore size 66+/-17microm, 0.54+/-0.02% porosity and 98% interconnectivity, measured by micro-computed tomography (microCT) analysis. The ability of the scaffolds to support osteogenic differentiation for subsequent cranial defect repair was evaluated by static and dynamic (0.035+/-0.006ms(-1) terminal velocity) cultivation with dura mater stem cells (DSCs). In vitro studies showed minimal increases in proliferation over 28 days in culture in osteogenic media. Alkaline phosphatase expression remained constant throughout the study. Moderate increases in matrix deposition, as assessed by histochemical staining and microCT analysis, occurred at later time points, days 21 and 28. Although constructs cultured dynamically showed greater mineralization than static conditions, these trends were not significant. It remains unclear whether bioreactor culture of DSCs is advantageous for bone tissue engineering applications. However, these studies show that polycaprolactone (PCL) scaffolds alone, without the addition of other co-polymers or ceramics, support long-term attachment and mineralization of DSCs throughout the entire porous scaffold.


Assuntos
Materiais Biocompatíveis/química , Técnicas de Cultura de Células/métodos , Dura-Máter/citologia , Osteoblastos/citologia , Poliésteres/química , Células-Tronco/citologia , Engenharia Tecidual/métodos , Animais , Materiais Biomiméticos/química , Diferenciação Celular , Células Cultivadas , Dura-Máter/fisiologia , Matriz Extracelular/química , Gases/química , Teste de Materiais , Osteoblastos/fisiologia , Osteogênese/fisiologia , Porosidade , Ratos
16.
Kidney Int ; 71(10): 977-84, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17377512

RESUMO

Preeclampsia is a complication of pregnancy with significant morbidity and mortality for the mother and the fetus. Presumptions are made that placental hypoxia has a causative role in the clinical syndrome. Furthermore, soluble fms-like tyrosine kinase 1 (sFLT-1) has been shown to have a role in the maternal syndrome of preeclampsia. We investigated the relationship between uteroplacental ischemia (UPI), the maternal clinical syndrome of preeclampsia and sFLT-1 in non-human primates. The induction of UPI in a pregnant non-human primate resulted in the development of a clinical entity analogous to human preeclampsia. This was illustrated by the increase in blood pressure, development of proteinuria, and renal histological changes identical to human preeclampsia. A significant elevation in the placental and peripheral blood mononuclear cell sFLT-1 mRNA expression was noted, translating to a significant elevation in circulating sFLT-1. Thus, this sequence suggests that a pathogenic reduction in placental perfusion results in the development of the maternal syndrome of preeclampsia and an increase in circulating sFLT-1, which is derived both from placental and extra-placental sources.


Assuntos
Hipertensão/etiologia , Isquemia/sangue , Isquemia/complicações , Placenta/irrigação sanguínea , Pré-Eclâmpsia/etiologia , Proteinúria/etiologia , Útero/irrigação sanguínea , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Animais , Feminino , Rim/metabolismo , Rim/patologia , Monócitos/metabolismo , Papio , Placenta/metabolismo , Pré-Eclâmpsia/patologia , Gravidez , RNA Mensageiro/metabolismo , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/sangue , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/genética
17.
Environ Sci Technol ; 40(18): 5817-22, 2006 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-17007146

RESUMO

In an effort to combat West Nile Virus, planes dispersed insecticide over Sacramento, CA, treating nearly 50,000 hectares with pyrethrins and the synergist piperonyl butoxide (PBO). Widespread dispersal of insecticide over a metropolitan area, coupled with extensive pretreatment data on the area's urban creeks, provided a unique opportunity to study effects of mosquito control agents on aquatic habitats within an urban setting. There was no evidence of aquatic toxicity from the two active ingredients in the product applied. However, PBO concentrations were high enough to enhance toxicity of pyrethroids already existing in creek sediments from general urban pesticide use. PBO concentrations of 2-4 microg/L were high enough to nearly double the toxicity of sediments to the amphipod Hyalella azteca. Though the increase in toxicity was modest, it was unexpected to find environmental synergy at all. Risk assessments for mosquito control agents have focused on the active ingredients but have failed to recognize the potential for interactions with pesticides previously existing in the environment, which in this case appeared to represent a risk to aquatic life greater than that of the active ingredients themselves.


Assuntos
Inseticidas/toxicidade , Controle de Mosquitos/métodos , Butóxido de Piperonila/toxicidade , Piretrinas/intoxicação , Poluentes Químicos da Água/toxicidade , Anfípodes/efeitos dos fármacos , Animais , Daphnia/efeitos dos fármacos , Sedimentos Geológicos , Inseticidas/química , Inseticidas/intoxicação , Butóxido de Piperonila/química , Butóxido de Piperonila/intoxicação , Piretrinas/química , Reforma Urbana , Poluentes Químicos da Água/química , Poluentes Químicos da Água/intoxicação
18.
J Anim Physiol Anim Nutr (Berl) ; 90(5-6): 230-7, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16684144

RESUMO

Growing indigenous Cambodian chickens and ducks, and broiler chickens and White Pekin ducks were fed diets containing 0%, 7%, 14% and 20% of cassava leaf meal (CLM) to study the effects of CLM level on diet digestibility and gastrointestinal tract (GIT) and organ development. The coefficient of total tract apparent digestibility (CTTAD) of dry matter (DM) and intake of digestible DM decreased with increased dietary CLM. DM and digestible DM intake was higher for local breeds than for the corresponding exotic breeds, and higher for ducks than for chickens (p < 0.001), although there were no species or breed effects on CTTAD of DM (p > 0.05). Weight of small intestine, caeca, gizzard and pancreas, expressed as per kg body weight, increased with increased CLM in the diet (p < 0.001). There was no consistent diet effect on liver weight. Length of small intestine and caeca, expressed on a mass-specific basis, increased with dietary CLM content (p < 0.001). When expressed as per kg body weight small intestine, proventriculus, gizzard, pancreas and liver weights, and small intestine length, were higher in ducks than in chickens (p < 0.001), and were higher in the indigenous than in the improved breeds (p < 0.01), except for small intestine weights, which were similar. However chickens had higher weight of caeca (p < 0.001) and colon (p < 0.01) in absolute units and per kg body weight.


Assuntos
Galinhas/metabolismo , Digestão , Patos/metabolismo , Manihot , Tamanho do Órgão/efeitos dos fármacos , Ração Animal , Animais , Cruzamento , Camboja , Galinhas/crescimento & desenvolvimento , Sistema Digestório/efeitos dos fármacos , Sistema Digestório/crescimento & desenvolvimento , Relação Dose-Resposta a Droga , Patos/crescimento & desenvolvimento , Masculino , Folhas de Planta/química , Distribuição Aleatória , Especificidade da Espécie
19.
Trop Anim Health Prod ; 36(7): 715-29, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15563032

RESUMO

An experiment was carried out to determine the effect of feeding brewery waste that replaced different levels of concentrate in diets for growing crossbred common ducks. A total of 300 ducks at 3 weeks of age were allocated in a 2 x 5 factorial experiment. Two feeding systems were compared, with the brewery waste provided separately (S) or mixed (M) with a concentrate. For the first feeding system the concentrate was fed alone (C100M), or replaced successively by brewery waste at ratios of concentrate to brewery waste: 75:25 (C75M), 50:50 (C50M) and 25:75 (C25M) on a dry matter basis, and fed ad libitum. For the second system concentrate and brewery waste were fed separately, with the same levels as in the first system. Total feed intakes for both feeding systems and intakes of brewery waste, total dry matter, crude protein, calcium and phosphorus increased significantly as concentrate was reduced (p <0.05). Daily weight gains were not significantly different between the two feeding systems, but were significantly lower for the C25 and C0 diets (p <0.05). Replacement of 50% of the concentrate by brewery waste resulted in the best growth performance. The highest net profits were from the separate feeding system, and for ducks fed brewery waste only (C0). It is concluded that brewery waste can replace traditional diets for crossbred common ducks based on concentrate.


Assuntos
Patos/crescimento & desenvolvimento , Resíduos Industriais , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Animais , Relação Dose-Resposta a Droga , Feminino , Masculino , Tamanho do Órgão , Distribuição Aleatória , Aumento de Peso
20.
Anat Rec A Discov Mol Cell Evol Biol ; 272(1): 398-402, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12704697

RESUMO

Human subcutaneous fat-derived stem cells were recently shown to have the potential to differentiate in vitro into a variety of cell types, including adipocytes, osteoblasts, chondrocytes, and myoblasts (Zuk et al., Tissue Eng. 2001;7:211-228). Subcutaneous adipose tissue may therefore prove to be an easily acquired and abundant source of stem cells. Presently it is unclear whether mammals such as rats (which possess small or nonexistent subcutaneous fat pads) contain mesenchymal stem cells within the visceral fat of the abdominal cavity, or whether the visceral fat of any species contains stem cells. In this study we isolated and expanded a pool of mesenchymal cells from visceral fat of adult Sprague-Dawley rats and induced their differentiation in vitro into adipocytes, osteoblasts, neural cells, and chondrocytes. The differentiated phenotypes were verified by morphology as well as detection and expression of tissue-specific protein and mRNA. We conclude that despite well-documented differences in the metabolic and biochemical properties among anatomically distinct depots of fat, the visceral fat of rats contains adult mesenchymal stem cells with developmental potential similar to those isolated from subcutaneous fat in humans. Therefore, animals such as rats provide both a source of fat-derived stem cells and an immunocompetent, autologous host animal in which to investigate the capacity of the fat-derived cells to differentiate and form tissues in vivo.


Assuntos
Tecido Adiposo/citologia , Tecido Adiposo/crescimento & desenvolvimento , Diferenciação Celular/fisiologia , Mesoderma/citologia , Células-Tronco Multipotentes/citologia , Adipócitos/citologia , Adipócitos/fisiologia , Animais , Biomarcadores , Linhagem da Célula/fisiologia , Células Cultivadas , Condrócitos/citologia , Condrócitos/fisiologia , Colágeno Tipo II/genética , Masculino , Mesoderma/fisiologia , Células-Tronco Multipotentes/fisiologia , Neurônios/citologia , Neurônios/fisiologia , Osteoblastos/citologia , Osteoblastos/fisiologia , Osteonectina/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores Citoplasmáticos e Nucleares/genética , Fatores de Transcrição/genética , Vísceras/citologia , Vísceras/crescimento & desenvolvimento , Proteínas tau/genética
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