Maternal interest in lambs smeared with polar and nonpolar substances

1989 ◽  
Vol 29 (4) ◽  
pp. 513 ◽  
Author(s):  
G Alexander ◽  
BS Goodrich ◽  
D Stevens ◽  
LR Bradley
Keyword(s):  
Polyethylene Glycol ◽  
Silicone Oil ◽  
Liquid Paraffin ◽  
Polar Components ◽  
Polar Materials ◽  
Before And After

Maternal interest in their own and alien lambs was examined in groups of 7-11 ewes before and after their lambs were coated with nonpolar substances (white soft paraffin or liquid paraffin), or more polar substances (polyethylene glycol, glycerol, silicone oil or diisooctylphthalate). Maternal interest in alien lambs was significantly increased by smearing lambs with the nonpolar material, but the effect was absent when lambs were washed before coating; more polar coatings had little or no effect. The coatings had little or no effect on the maternal interest in the ewe's own lambs. We suggest that coatings of polar materials, while dissolving polar components from the skin and wool, does not prevent the release of volatile nonpolar constituents which ewes employ to distinguish between lambs. We also suggest that nonpolar coatings dissolve and retard the release of lamb odour components of similar polarity, while permitting the release of other constituents which appear generally attractive to maternal ewes, and result in increased acceptance of alien lambs.

Assessment of Color Stability of Treated Leathers with Silicone Oil and Polyethylene Glycol

2014 ◽  
Vol 1 (1) ◽  
pp. 24-34
Author(s):  
Alireza K. ◽  
Hossein Ahmadi ◽  
Mohsen Mohammadi
Keyword(s):  
Ascorbic Acid ◽  
Polyethylene Glycol ◽  
Treatment Process ◽  
Color Change ◽  
Silicone Oil ◽  
Accelerated Aging ◽  
Color Stability ◽  
Antioxidant Additive ◽  
Before And After ◽  
Aesthetic Values

Lubricants and leather dressings are the most common treatments of dry and water logged historical leathers. Color change has a great importance during the time and treatment process, due to visual and aesthetic values of historic leather relics. Polyethylene glycol (PEG) and silicone oil (SiO) are frequently used leather dressings in the conservation procedures. Therefore, color stability of treated leathers with PEG and SiO were investigated before and after heat accelerated aging. Moreover, application of ascorbic acid was evaluated as an antioxidant additive for PEG (PEG+AA).Color change after treatment and aging were studied by colorimetry technique in the CIE *L*a*b system. Results indicated to severe color alteration in PEG treated and aged leathers with or without ascorbic acid. Whereas, SiO treated samples showed better stability and minimum color shift after aging. Silicone oil was characterized as the best dressing for historical leathers with compared to PEG and PEG+AA, due to its high stability and aesthetical properties.

scholarly journals Bowel preparation for performing a colonoscopy: prospective randomized comparison study between a low-volume solution of polyethylene glycol and bisacodyl versus bisacodyl and a mannitol solution

2012 ◽  
Vol 49 (2) ◽  
pp. 162-168 ◽  
Author(s):  
Manoel Carlos Vieira ◽  
Claudio Lyoiti Hashimoto ◽  
Flair José Carrilho
Keyword(s):  
Polyethylene Glycol ◽  
Vital Signs ◽  
Abdominal Distension ◽  
Similar Efficacy ◽  
Preparation Methods ◽  
Gold Standard Method ◽  
Mannitol Solution ◽  
Before And After ◽  
Glycol Solution

CONTEXT: Colonoscopy is currently the gold standard method to examine the colon, the rectum and the terminal ileum. In order to perform the colonoscopy, it is necessary to clean the bowel and use medications that are generally poorly tolerated by the patients. OBJECTIVE: Compare the tolerability, acceptability, safety and efficacy of two solutions used for intestinal preparation for a colonoscopy. METHODS: One hundred patients matched for sex and age were prospective randomized into two groups. Polyethylene glycol group received bisacodyl 10 mg plus 1 L of polyethylene glycol the night before and 1 L on the day of the exam. Mannitol group received bisacodyl 20 mg the day before and 1 L of a 10% mannitol solution on the day of the exam. The diet was the same for both groups. Tolerability and acceptability were measured using previously validated questionnaires. In terms of safety, variations in vital signs before and after the preparation were recorded, in addition to any complications. The quality of the preparation was graded based on the Boston and Ottawa scales. RESULTS: Ninety-six percent (96%) completed the study. As for tolerability, the mannitol preparation group exhibited a significantly higher frequency of nausea, vomiting, abdominal pain, and abdominal distension than polyethylene glycol group (P < 0.05). Acceptability was significantly better in polyethylene glycol group. The polyethylene glycol solution has also previously been shown to be safer than mannitol. No difference was observed in the quality of the preparation between the two preparation methods. CONCLUSIONS: The following conclusions can be made: polyethylene glycol solution had higher tolerability, acceptability, and safety than the mannitol and should be used instead of mannitol. Both preparation solutions have similar efficacy.

Evaluation of percentage recovery together with modified reference range in hyperprolactinemia

2019 ◽  
Vol 45 (1) ◽  
pp. 37-43
Author(s):  
Melahat Dirican ◽  
Hacer Ebru Açıkgöz ◽  
Emre Sarandöl
Keyword(s):  
Polyethylene Glycol ◽  
Reference Range ◽  
Added Value ◽  
Percentage Recovery ◽  
Before And After ◽  
Recovery Percentage ◽  
Discrimination Capacity ◽  
Polyethylene Glycol Precipitation

Abstract Objective Macroprolactinemia is an important cause of hyperprolactinemia. The aim of this study was to examine the added value of the consideration of modified reference range in determination of macroprolactinemia and true hyperprolactinemia. Materials and methods Three hundred and ninety patients with high and 131 with normal prolactin (PRL) levels were included in this study. PRL had been analyzed before and after polyethylene glycol precipitation (post-PEG PRL). Recovery percentage (R%) <40% and >60% had been reported as macroprolactinemia and true hyperprolactinemia, respectively. Post-PEG PRL levels were evaluated according to the modified reference range obtained from those of the normoprolactinemic subjects. Results According to the R% criterion; macroprolactinemia had been detected in 24.9% and true hyperprolactinemia in 67.4% of hyperprolactinemic patients. When the data were evaluated considering the post-PEG PRL levels according to the modified reference range; 13 (13.4%) of the 97 macroprolactinemia reports would be considered as true hyperprolactinemia and 6 (2.3%) of the 263 true hyperprolactinemia reports would be changed as macroprolactinemia. Conclusion Discrimination capacity of R% criterion for true hyperprolactinemia and macroprolactinemia is limited, and we suggest that, in accordance with R% criterion, laboratory reports should include the post-PEG PRL levels along with the modified reference range.

scholarly journals The effect of silicone oil tamponade on retinal layers and choroidal thickness in patients with rhegmatogenous retinal detachment: a systematic review and meta-analysis

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Heshmatollah Ghanbari ◽  
Farzan Kianersi ◽  
Alireza Jamshidi Madad ◽  
Alireza Dehghani ◽  
Alireza Rahimi ◽  
...  
Keyword(s):  
Retinal Detachment ◽  
Choroidal Thickness ◽  
Rhegmatogenous Retinal Detachment ◽  
Silicone Oil ◽  
Meta Analysis ◽  
Cochrane Library ◽  
Subfoveal Choroidal Thickness ◽  
Retinal Layers ◽  
Significant Difference ◽  
Before And After

Abstract Background To evaluate the effects of intravitreal silicone oil (SO) on the retinal and choroidal thickness in eyes with rhegmatogenous retinal detachment (RRD). Methods A literature search was performed in Web of Science, Scopus, ProQuest, Embase, Clinical Key, Science Direct, Cochrane Library, and Springer, as well as Persian databases, including IranDoc, MagIran, SID, MOH thesis, and MOH articles until June 2020. Two reviewers independently searched and extracted the data. Results Sixteen studies (n = 391) met the inclusion criteria. The meta-analysis showed that the SO tamponade could significantly reduce the central macular thickness (CMT) in patients with RRD as compared to gas tamponade WMD = − 14.91; 95% CI: − 22.23, − 7.60; P < 0.001, I2 = 71%). No significant change was found in CMT between the eye with SO tamponade (after SO removal) and the fellow healthy eye in patients with RRD (WMD = − 3.52; 95% CI: − 17.63, 10.59; I2 = 68.6%). Compared to the preoperative stage, the SO tamponade could significantly reduce the subfoveal choroidal thickness in patients with RRD (WMD = − 18.67, 95% CI: − 30.07, − 1.28; I2 = 80.1%). However, there was no significant difference in the subfoveal choroidal thickness before and after SO removal (WMD = − 1.13, 95% CI: − 5.97, 3.71; I2 = 87.6%). Conclusion The SO tamponade had a significant effect on the reduction of retinal layers and the subfoveal choroidal thickness.

scholarly journals Effect of Duration of Silicone Oil Tamponade on Retinal Structure after Rhegmatogenous Retinal Detachment Surgery

2021 ◽  
pp. 1-8
Author(s):  
Chloé Dubroux ◽  
Julia Salleron ◽  
Karine Angioi-Duprez ◽  
Jean-Paul Berrod ◽  
Jean-Baptiste Conart
Keyword(s):  
Retinal Detachment ◽  
Rhegmatogenous Retinal Detachment ◽  
Silicone Oil ◽  
Case Series ◽  
Retinal Layer ◽  
Before And After ◽  
Silicone Oil Tamponade ◽  
Group 2 ◽  
Change In Mean ◽  
Group 1

<b><i>Purpose:</i></b> The aim of the study was to investigate the effect of tamponade duration on retinal changes induced by silicone oil (SO) in patients who underwent successful rhegmatogenous retinal detachment (RRD) surgery. <b><i>Methods:</i></b> Retrospective comparative case series of 68 patients who underwent SO tamponade for RRD. Patients were divided into 2 groups based on timing of SO removal: &#x3c;6 months (group 1, <i>n</i> = 34) versus ≥6 months (group 2, <i>n</i> = 34). The main outcome measure was the change in central macular, inner, and outer retinal layer thickness (CMT, IRLT, and ORLT) before and after SO removal (SOR). <b><i>Results:</i></b> The median tamponade duration was 4 [Clin Ophthalmol. 2016;10:471–6, Zhonghua Yan Ke Za Zhi. 1997 Jan;33(1):39–41] months in group 1 and 8 [Arch Ophthalmol. 1994 Jun;112(6):778–85, Retina. 2004 Dec;24(6):871–7] months in group 2 (<i>p</i> &#x3c; 0.001). The mean CMT significantly increased from 245.3 ± 22.2 μm and 238.8 ± 41.6 μm under SO to 281.3 ± 60.2 μm and 259.0 ± 43.5 μm after SOR in group 1 (<i>p</i> = 0.009) and in group 2 (<i>p</i> = 0.007), respectively. Automated segmentation measurement revealed a significant increase in mean IRLT (<i>p</i> = 0.014 and <i>p</i> = 0.013) but no change in mean ORLT (<i>p</i> = 0.080 and <i>p</i> = 0.257) in both groups. After adjustment, there was no difference between the 2 groups in terms of mean final CMT, IRLT, and ORLT and mean retinal thickness changes after SOR. There was also no correlation between the tamponade duration and macular microstructural changes or visual recovery. <b><i>Conclusion:</i></b> SO tamponade causes a thinning of all retinal layers, mainly affecting the inner retinal layer. However, these changes resolved following SO extraction and were not affected by longer tamponade duration.

scholarly journals Retinal Sensitivity before and after Silicone Oil Removal Using Microperimetry

2019 ◽  
Vol 2019 ◽  
pp. 1-5
Author(s):  
Ghada A. Nassar ◽  
Maha M. Youssef ◽  
Lameece M. Hassan ◽  
Hebatalla S. Makled
Keyword(s):  
Silicone Oil ◽  
Retinal Sensitivity ◽  
Oil Removal ◽  
Corrected Visual Acuity ◽  
Significant Difference ◽  
Before And After ◽  
Group A ◽  
The Mean ◽  
Group B ◽  
Best Corrected Visual Acuity

The purpose of the study is to assess the retinal sensitivity, using microperimetry, before and after silicone removal. It included 22 patients admitted for silicone removal after vitrectomy for macula-off retinal detachment. Patients were divided into 2 groups according to the duration of silicone tamponade: Group A: <3 months (included 10 patients), and Group B: 3–6 months (included 12 patients). Retinal sensitivity was tested, using microperimetry, one day before and one month after silicone removal. The best-corrected visual acuity (in LogMAR) significantly improved postoperatively (0.69 versus 1.06 and 0.69 versus 1.07 in Groups A and B, respectively). The mean intraocular pressure (IOP) was 12.89 ± 1.05 mmHg postoperatively versus 14.89 ± 1.76 mmHg preoperatively in Group A (p=0.011) and was 13.33 ± 1.30 mmHg postoperatively versus 15.33 ± 3.11 mmHg preoperatively in Group B (p=0.008). In Group A, the mean postoperative overall retinal sensitivity was 8.70 ± 2.56 dB versus 5.68 ± 2.00 dB preoperatively (p=0.008). In Group B, it was 9.83 ± 3.36 dB versus 7.00 ± 2.55 dB (p=0.002). No statistically significant difference was found between the two groups as regards improvement in overall retinal sensitivity. We concluded that the overall retinal sensitivity significantly increased following silicone removal in both groups. This trial is registered with ISRCTN43187564.

scholarly journals Comparative Compressibility of Smectite Group under Anhydrous and Hydrous Environments

Materials ◽  
2020 ◽  
Vol 13 (17) ◽  
pp. 3784
Author(s):  
Yongmoon Lee ◽  
Pyosang Kim ◽  
Hyeonsu Kim ◽  
Donghoon Seoung
Keyword(s):  
High Pressure ◽  
Powder Diffraction ◽  
Room Temperature ◽  
Environmental Changes ◽  
Silicone Oil ◽  
Distilled Water ◽  
X Ray ◽  
Water Conditions ◽  
Before And After ◽  
Cell Volumes

High-pressure synchrotron X-ray powder diffraction studies of smectite group minerals (beidellite, montmorillonite, and nontronite) reveal comparative volumetric changes in the presence of different fluids, as pressure transmitting media (PTM) of silicone oil and distilled water for anhydrous and hydrous environments at room temperature. Using silicone oil PTM, all minerals show gradual contraction of unit-cell volumes and atomistic interplane distances. They, however, show abrupt collapse near 1.0 GPa under distilled water conditions due to hydrostatic to quasi-hydrostatic environmental changes of water PTM around samples concomitant with the transition from liquid to ICE-VI and ICE-VII. The degrees of volume contractions of beidellite, montmorillonite, and nontronite up to ca. 3 GPa are ca. 6.6%, 8.9%, and 7.5% with bulk moduli of ca. 38(1) GPa, 31(2) GPa, and 26(1) GPa under silicone oil pressure, whereas 13(1) GPa, 13(2) GPa, and 17(2) GPa, and 17(1) GPa, 20(1) GPa, and 21(1) GPa under hydrostatic and quasi-hydrostatic environments before and after 1.50 GPa, respectively.

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