Effect of Ultrasound on the Fetus

1987 ◽  
Vol 8 (8) ◽  
pp. 228-253
Keyword(s):  
Adverse Effects ◽  
Human Fetus ◽  
Matched Control ◽  
Subsequent Development ◽  
Childhood Malignancy ◽  
Ultrasonic Examination ◽  
The United Kingdom ◽  
Dna Alterations ◽  
And Control

The question of adverse effects of ultrasonic examination upon the human fetus continues to be explored. The impetus for these investigations comes from animal or in vitro cellular studies showing a reduction of weight and size and DNA alterations in mice litters exposed to ultrasound. Human studies to date have failed to reveal any comparable results. These two articles explore whether there is a positive correlation between fetal ultrasonic examination and/or monitoring and subsequent development of childhood malignancy. The first study reports comparison of histories from 1,731 children who died of cancer in the United Kingdom between 1972 and 1981 with age-matched control children for exposure. Six percent of both case and control children had had ultrasonic exposure.

scholarly journals A pilot study on the prevalence of lice in Irish beef cattle and the first Irish report of deltamethrin tolerance in Bovicola bovis

2021 ◽  
Vol 74 (1) ◽  
Author(s):  
Fiona Mckiernan ◽  
Jack O’Connor ◽  
William Minchin ◽  
Edward O’Riordan ◽  
Alan Dillon ◽  
...  
Keyword(s):  
Beef Cattle ◽  
First Record ◽  
Synthetic Pyrethroids ◽  
Skin Damage ◽  
Macrocyclic Lactones ◽  
The United Kingdom ◽  
Cattle Herds ◽  
Linognathus Vituli ◽  
And Control

Abstract Background Pediculosis in cattle causes significant itching, irritation and stress to the animal, often resulting in skin damage and poor coat condition. The control of bovine pediculosis in Ireland is based predominantly on commercial insecticides belonging to one of two chemical classes, the synthetic pyrethroids and the macrocyclic lactones. In recent years, pyrethroid tolerance has been reported in a number of species of livestock lice in the United Kingdom and Australia. Results In this pilot survey, lice were detected in 16 (94%) out of 17 herds visited. Two species of lice, Bovicola bovis and Linognathus vituli were identified. In vitro contact bioassays showed evidence of deltamethrin tolerance in Bovicola bovis collected from 4 farms. This was confirmed by repeatedly assessing louse infestations on treated animals on one farm. Conclusions To our knowledge this is the first record of insecticide tolerant populations of lice in Irish cattle. The results also provide new data on the species of lice infesting beef cattle in Ireland and the prevalence and control of louse infestations in Irish beef cattle herds.

102 EFFECT OF DEMECOLCINE PRE-TREATMENT ON VIABILITY, TIMING OF FIRST POLAR BODY EXTRUSION, SPINDLE CONFIGURATION, AND SUBSEQUENT DEVELOPMENT OF OVINE OOCYTES VITRIFIED AT GERMINAL VESICLE STAGE

2010 ◽  
Vol 22 (1) ◽  
pp. 210 ◽  
Author(s):  
A. R. Moawad ◽  
J. Zhu ◽  
I. Choi ◽  
K. H. S. Campbell
Keyword(s):  
Polar Body ◽  
Germinal Vesicle ◽  
Subsequent Development ◽  
Developmental Competence ◽  
Blastocyst Development ◽  
Vitro Fertilization ◽  
First Polar Body ◽  
Polar Body Extrusion ◽  
And Control

Oocyte cryopreservation is a potentially valuable way of preserving female germ cells. However, to date the reported developmental competence of cryopreserved oocytes is low. The objectives of this study were to investigate the effects of demecolcine pretreatment on viability, timing of the first polar body extrusion (PBI), spindle, chromatin organization, and in vitro embryo development of ovine vitrified germinal vesicle (GV) oocytes after in vitro fertilization (IVF) and parthenogenetic activation. Cumulus-oocyte complexes (COC) aspirated from ovine ovaries collected at slaughter were selected and randomly divided into 3 groups: (1) untreated (in vitro matured, IVM) as a control, (2) vitrified (Moawad AR et al. 2009 Reprod. Fertil. Dev. 21, 135 abst), and (3) deme + vitrified (oocytes were incubated with 0.1 μg mL-1 demecolcine for 20 min before vitrification). After vitrification COC were thawed and matured in vitro for 24 h. Following IVM, oocytes from 3 groups were subsequently subjected to (1) immunostaining, (2) IVF, or (3) activation. Presumptive zygotes were cultured in vitro in SOF media for 7 days. Data were analyzed using chisquare and t-test. No significant differences (P > 0.05) were observed in survival rates between deme + vitrified (90.8%, 324/357) and vitrified (87.2%, 211/242). However, the numbers of oocytes with PBI in two vitrified groups at 18 h (20.4 and 8.5 v. 47.1%) and 24 h post IVM (51 and 43.2 v. 88.5%) were significantly lower (P < 0.01) than those in the control. Percentage of normal spindle and chromatin configuration in the two vitrified groups also significantly decreased (P < 0.05) compared with those in the control (42.5 and 41.8 v. 76.5%), whereas missing spindle in the 2 vitrified groups significantly increased (P < 0.001) compared with the controls (47.5 and 32.7 v. 3.9%). Following IVF (pi), cleavage rates at 24.48 hpi and morula development (5 days pi) were significantly lower (P < 0.001) in deme + vitrified (6.1, 43.1, and 28.5%) and vitrified groups (3.3, 30.1, and 22.9%) than control (50.4, 82.4, and 46.4%). Blastocyst development in deme + vitrified (9.8%) and control (33.6%) was significantly higher (P < 0.01) than in vitrified group (1.3%). Hatched blastocysts were observed only in deme + vitrified and control groups (4.9 v. 12.8%). In addition, post activation (pa) cleavage rates in deme + vitrified (10.3 v. 40.7%) and control (52.5 v. 76.7%) at 24 and 48 hpa were significantly higher (P < 0.05) than those in the vitrified group. Blastocyst development in deme + vitrified (4.8%) was higher than that in the vitrified group (1.8%), but not significant (P > 0.05); however, these values were still significantly lower (P < 0.001) than those in the control (24.2%). No significant differences were observed in total cell numbers per blastocyst between all the groups. Taken together, these results suggest that pretreatment of oocytes with demecolcine before vitrification could improve the developmental competence of ovine vitrified-thawed GV-stage oocytes. A. R. Moawad was supported by the Egyptian government.

Comparative metabolism of plasminogen glycoforms I and II in the alloxan-diabetic rabbit

1995 ◽  
Vol 269 (6) ◽  
pp. E1017-E1023 ◽  
Author(s):  
M. W. Hatton ◽  
S. M. Southward ◽  
B. Ross-Ouellet ◽  
M. Richardson ◽  
P. D. Winocour
Keyword(s):  
Matched Control ◽  
Quantitative Difference ◽  
Half Time ◽  
Control Rabbit ◽  
Comparative Metabolism ◽  
Diabetic Rabbit ◽  
Diabetic Rabbits ◽  
And Control

The metabolism of plasminogen glycoforms I and II was measured in alloxan-induced diabetic and in age-matched control rabbits. Radiolabeled plasminogen I and II were degraded significantly more slowly in diabetic compared with control rabbits; plasminogen II [half-time (T1/2), 1.31 days] was degraded faster than plasminogen I (T1/2), 1.86 days) in diabetic rabbits and in control rabbits (T1/2, 1.18 and 1.58 days, respectively). From the catabolic rates and relative quantities in plasma, we calculated that approximately four molecules of plasminogen II were degraded for one molecule of plasminogen I in the diabetic and control rabbits. To verify this later observation, plasminogen I and II production by diabetic rabbit livers was compared with that by the control livers in vitro. During perfusion with [3H]leucine, 3H-labeled protein was released more slowly from diabetic than from control livers, but no quantitative difference in total plasminogen yield between diabetic and control livers was found. Nevertheless, plasminogen II was produced 0.7 +/- 0.4 and 4.3 +/- 0.3 times faster than plasminogen I by diabetic and control livers, respectively. Plasminogen metabolism in the diabetic rabbit did not differ qualitatively from that in the control rabbit except that catabolism was slowed.

scholarly journals 154 EFFECTS OF BLASTOMERE BIOPSY AND OXYGEN CONCENTRATION DURING CULTURE ON THE DEVELOPMENT AND INTERFERON-TAU SECRETION OF BOVINE EMBRYOS

2005 ◽  
Vol 17 (2) ◽  
pp. 227
Author(s):  
K.M. Johnson ◽  
X. Alvarez ◽  
H.M. Kubisch
Keyword(s):  
Genetic Diagnosis ◽  
Subsequent Development ◽  
Blastocyst Stage ◽  
Optimal Time ◽  
Human Embryos ◽  
Bovine Embryos ◽  
Blastocyst Formation ◽  
Interferon Tau ◽  
And Control

Pre-implantation genetic diagnosis has become a powerful tool in human in vitro fertilization. Yet, for ethical reasons, controlled experiments assessing the effects of embryo biopsies on human embryos are difficult to perform. Therefore, a series of experiments was performed to examine the effects of blastomere biopsies on subsequent development of IVF-derived bovine embryos cultured under either atmospheric or low (5%) oxygen. Embryos were generated by IVF of in vitro-matured oocytes and cultured in CR1aa medium containing 5% bovine fetal serum. The first experiment was designed to assess the optimal time for blastomere removal. One blastomere was removed from each of a large number of embryos at either 48 or 72 h after IVF. Biopsy at 48 h resulted in 17.2% (10/58) of embryos proceeding to the blastocyst stage, which was significantly lower than when biopsies were performed at 72 h (37.5% (33/88), P < 0.05). In the second experiment, embryos were cultured under either atmospheric or 5% O2 following blastomere removal. Biopsies at 72 h had no effect on rate of blastocyst formation with 38.5% (110/286) of controls and 33.7% (60/178) of biopsied embryos proceeding to the blastocyst stage. However, culture under 5% O2 significantly increased the number of blastocysts from 29.9% (69/231) to 43.3% (101/233). This effect was significant in both biopsied and control embryos. In contrast, staining of blastocysts for cell numbers did not reveal any effects of biopsies or culture conditions. In the final experiment, biopsies were again performed at 72 h and embryos were cultured as previously. Blastocysts were collected and cultured individually for 48 h in 50-μL-medium droplets in their respective O2 concentrations after which time the medium was assayed for concentration of interferon-tau (IFN-τ). Previous work has shown that IFN-τ secretion can be affected by genetic and environmental factors. Reduced O2 concentration again significantly increased blastocyst formation from 24.9 to 36.9% (49/197 vs. 75/203, P < 0.05), while blastomere removal had no effect on development. IFN-τ secretion did not differ between biopsied and control blastocysts, although culture under atmospheric O2 resulted in significantly increased IFN-τ concentration in medium droplets (12,690.1 ± 2715.6 vs. 4726.8 ± 2488.5 pM, P < 0.05). This work was supported by a grant (HMK) from the National Institutes of Health (HD 36421).

70 VITRIFICATION OF IMMATURE OVINE OOCYTES WITH CRYOLOOP: EFFECT OF CYTOCHALASIN B PRETREATMENT ON SUBSEQUENT DEVELOPMENT

2009 ◽  
Vol 21 (1) ◽  
pp. 135
Author(s):  
A. R. Moawad ◽  
I. Choi ◽  
J. Zhu ◽  
K. H. S. Campbell
Keyword(s):  
Cytochalasin B ◽  
Mammalian Species ◽  
Subsequent Development ◽  
Total Cell ◽  
High Survival ◽  
Control Groups ◽  
Cell Numbers ◽  
Significant Difference ◽  
And Control

Oocyte cryopreservation is still a challenge in most mammalian species because of their extreme sensitivity to chilling injuries. Relaxation of the cytoskeleton during vitrification may improve post-thaw survival and subsequent development; however, a previous study in immature [germinal vesicle (GV) stage] oocytes from prepubertal lambs reported that pretreatment with cytochalasin B (CB) did not improve maturation (Silvestre MA et al. 2006 Anim. Reprod. Sci. 93, 176–182). We previously reported that GV oocytes from mature ewes can be vitrified using a cryoloop with high survival, maturation, and subsequent in vitro fertilization (Moawad AR and Campbell KHS 2008 Reprod. Fertil. Dev. 20, 122). The aim of this study was to evaluate the effects of CB pretreatment prior to vitrification of GV oocytes (from mature ewes) on subsequent development. Cumulus–oocyte complexes obtained at slaughter were randomly divided into 2 groups and incubated with or without 7.5 μg mL–1 CB for 60 min before vitrification. Oocytes from each group were vitrified or used as toxicity and controls. For vitrification, oocytes were equilibrated in 10% ethylene glycol (EG) and 0.25 m trehalose (T) in HEPES/TCM-199 plus 10% fetal bovine serum (BM) for 3 min. Oocytes were then exposed to vitrification solution (20% EG and 20% DMSO in BM), loaded into the cryoloop within 1 min, and immersed in liquid nitrogen. Oocytes were warmed by exposure to (1) 10% EG and 1 m T in BM, (2) 0.5 m T in BM, and (3) BM for 3 min in each solution at 39°C. Oocytes were then matured, fertilized, and cultured in vitro as previously described. The frequency of cleavage 24 and 48 h post-insemination (pi), development to morula (5 days pi), blastocyst (7 days pi), and total cell numbers of blastocyst-stage embryos were evaluated. Cleavage was significantly lower (P < 0.001) in vitrified and CB-vitrified groups at both 24 h pi (15.2 v. 14.7%) and 48 h pi (27.3 v. 23.5%) than in other groups. Development to morula stage was significantly lower (P < 0.001) in vitrified and CB-vitrified oocytes (12.1 v. 17.7%) than in toxicity, CB-control, and control groups (43.1, 42.6, and 52.8%, respectively); however, no significant difference (P > 0.05) was observed between CB-vitrified and CB-toxicity groups. There was a significant decrease (P < 0.01) in development to blastocyst in CB-vitrified (2.9%) compared with CB-control (22.9%) and control (24.5%), but this did not differ significantly (P > 0.05) from toxicity and CB-toxicity groups (9.8 v. 11.4%). No blastocysts developed from the vitrified group. Hatched blastocysts were observed only in CB-control and control groups (8.2 v. 5.7%). Total cell numbers were significantly greater (P < 0.05) in control blastocysts than in toxicity, CB-vitrified, and CB-control (143 v. 87.25, 73, and 82, respectively). However, this did not differ significantly from the CB-toxicity group (115). These results support our previous data and suggest that pretreatment of GV-stage ovine oocytes with CB prior to vitrification has a positive effect on subsequent development.

Spindle configuration and developmental competence of in vitro-matured bovine oocytes exposed to NaCl or sucrose prior to Cryotop vitrification

2016 ◽  
Vol 28 (10) ◽  
pp. 1560 ◽  
Author(s):  
Núria Arcarons ◽  
Roser Morató ◽  
Jozé F. W. Spricigo ◽  
Marcia A. M. M. Ferraz ◽  
Teresa Mogas
Keyword(s):  
Adverse Effects ◽  
Embryo Development ◽  
Sucrose Solution ◽  
Developmental Competence ◽  
Control Groups ◽  
Sucrose Solutions ◽  
High Concentrations ◽  
And Control ◽  
Bovine Oocytes

In the present study we examined whether exposure to high concentrations of NaCl or sucrose before vitrification improves the cryotolerance of in vitro-matured bovine oocytes. In Experiment 1, oocytes were exposed to different concentrations of NaCl (375–1517 mOsm) or sucrose (375–812 mOsm) for 1 h. On the basis of the results of this experiment, in Experiment 2 oocytes were exposed to 0.25% NaCl (375 mOsmol) or 2.77% sucrose (375 mOsmol) solution, vitrified and warmed. Microtubule and chromosome configurations were examined by immunocytochemistry. In Experiment 3, in vitro embryo development was assessed after vitrification of oocytes with or without 2.77% sucrose (375 mOsmol) pretreatment. There was a similar percentage of oocytes showing normal spindle configurations in the sucrose-pretreated and control groups. Higher rates of abnormal spindles were found in groups treated with NaCl or sucrose solutions with >375 mOsmol. After vitrification and warming, a significantly higher percentage of oocytes with normal chromosome configurations was recorded for oocytes exposed to 375 mOsmol sucrose solution before vitrification compared with the control vitrified oocytes. However, these percentages were significantly lower than those recorded in untreated controls. Cleavage and blastocyst rates were higher in non-vitrified than vitrified oocytes. In conclusion, pretreatment with 375 mOsmol NaCl or sucrose solution had no adverse effects on the spindle status of vitrified–warmed cow oocytes. However, sucrose pretreatment offered no benefits for embryo development.

Nature and Origin of Micropollutants

1982 ◽  
Vol 14 (12) ◽  
pp. 5-14 ◽  
Author(s):  
D Mackay
Keyword(s):  
Adverse Effects ◽  
Toxicity Data ◽  
Low Level ◽  
Environmental Models ◽  
Toxic Event ◽  
And Control

The origins of “micropollutants” are discussed and classified. It is suggested that assessing the risk and ensuring an acceptably low level of adverse effects from these substances requires information or control of three factors (exposure, toxicity and characteristics of the victim or organism) which combine to generate the toxic event. Methods of estimating exposure are discussed, especially environmental models. Ultimately, it should be possible to couple these models to toxicity data in a rational, rigorous manner to elucidate the extent of risk and control it to acceptable levels.

Anti-Mycobacterial Peroxides: A New Class of Agents for Development Against Tuberculosis

2020 ◽  
Vol 16 (3) ◽  
pp. 392-402
Author(s):  
Christiaan W. van der Westhuyzen ◽  
Richard K. Haynes ◽  
Jenny-Lee Panayides ◽  
Ian Wiid ◽  
Christopher J. Parkinson
Keyword(s):  
Subsequent Development ◽  
Antitubercular Activity ◽  
Organic Peroxide ◽  
New Drugs ◽  
Skeletal Myoblast ◽  
Artemisinin Derivatives ◽  
Malaria Therapy ◽  
New Class ◽  
Alternative Approach

Background: With few exceptions, existing tuberculosis drugs were developed many years ago and resistance profiles have emerged. This has created a need for new drugs with discrete modes of action. There is evidence that tuberculosis (like other bacteria) is susceptible to oxidative pressure and this has yet to be properly utilised as a therapeutic approach in a manner similar to that which has proven highly successful in malaria therapy. Objective: To develop an alternative approach to the incorporation of bacterial siderophores that results in the creation of antitubercular peroxidic leads for subsequent development as novel agents against tuberculosis. Methods: Eight novel peroxides were prepared and the antitubercular activity (H37Rv) was compared to existing artemisinin derivatives in vitro. The potential for toxicity was evaluated against the L6 rat skeletal myoblast and HeLa cervical cancer lines in vitro. Results: The addition of a pyrimidinyl residue to an artemisinin or, preferably, a tetraoxane peroxidic structure results in antitubercular activity in vitro. The same effect is not observed in the absence of the pyrimidine or with other heteroaromatic substituents. Conclusion: The incorporation of a pyrimidinyl residue adjacent to the peroxidic function in an organic peroxide results in anti-tubercular activity in an otherwise inactive peroxidic compound. This will be a useful approach for creating oxidative drugs to target tuberculosis.

Sign in / Sign up

Export Citation Format

Share Document