High‐Yield Purification of Giardia intestinalis Cysts from Fecal Samples

2020 ◽  
Vol 59 (1) ◽  
Author(s):  
Paul Ogbuigwe ◽  
Anthony B. Pita ◽  
Matthew A. Knox ◽  
Niluka Velathanthiri ◽  
David T. S. Hayman
Keyword(s):  
Giardia Intestinalis ◽  
High Yield ◽  
Fecal Samples

scholarly journals FREQUENCY OF ENTEROPARASITOSES IN PRESCHOOL CHILDREN ATTENDING DAYCARE CENTERS: A SURVEY APPLYING PARASITOLOGICAL AND IMMUNOLOGICAL METHODS

2019 ◽  
Vol 48 (2) ◽  
pp. 121-133
Author(s):  
Gabriela Cardoso Goes ◽  
Karina Costa Coelho Gonçalves ◽  
Adriana Pittella Sudré ◽  
Danuza Pinheiro Bastos Garcia Mattos ◽  
Beatriz Brener ◽  
...  
Keyword(s):  
Optical Microscopy ◽  
Entamoeba Histolytica ◽  
Intestinal Parasites ◽  
Parasite Infection ◽  
Giardia Intestinalis ◽  
Diagnostic Methods ◽  
Immunological Methods ◽  
Enzyme Linked Immunosorbent Assay ◽  
Fecal Samples ◽  
Daycare Centers

The present study evaluated the frequency of intestinal parasitoses in children in public day care centers applying parasitological and immunological diagnostic methods. Fecal samples from 121 children from six public daycare centers were analyzed using parasitological techniques. Epidemiological data were obtained through a questionnaire, where parents and / or guardians were asked, for instance, whether the children had contact with soil, ate raw food, such as vegetables or raw or undercooked meat, normally walked around barefoot or had contact with animals. Fecal samples from 82 children were also tested for Giardia intestinalis and Cryptosporidium sp. coproantigen using the enzyme-linked immunosorbent assay (ELISA) which was also used for Entamoeba coproantigen detection only in samples that tested positive for the parasite by parasitological stool exam/optical microscopy. Intestinal parasite infection was noted in 23.1% (28/121) of the children. The most frequent parasite was Giardia intestinalis (13.2%), followed by Entamoeba coli (5.8%), Blastocystis spp. (1.7%), Endolimax nana (1.7%), Enterobius vermicularis (1.7%), Cystoisospora belli (0.8%),Entamoeba histolytica/E. dispar complex (0.8%), and Ascaris lumbricoides (0.8%). Positivity for parasite infection using parasitological stool exams was significantly associated with age groups, with a higher frequency in 4 to 6 year old children (p=0.03). No association or significant variations were noted in the prevalence of intestinal parasites in relation to the epidemiological variables studied. All samples were negative for Cryptosporidium sp. and Entamoeba histolytica detected by immunological testing, and 17.1% (14/82) children tested positive for Giardia intestinalis, although using parasitological exam/optical microscopy, only 14.6% (12/82) tested positive. The high incidence of intestinal parasites, especially protozoans, suggests probable interpersonal transmission among the children, environmental contamination, or even contaminated food/water intake. Thus, consolidation of preventive measures and efficient diagnostic resources as well as control of intestinal parasites and patient treatment are of utmost importance.

Quick and efficient purification of Giardia intestinalis cysts from fecal samples

2006 ◽  
Vol 99 (3) ◽  
pp. 300-302 ◽  
Author(s):  
M. E. Alvarado ◽  
M. Wasserman
Keyword(s):  
Giardia Intestinalis ◽  
Fecal Samples

Quality films from carbon fiber evaporation for thorough coverage of TEM grids

1988 ◽  
Vol 46 ◽  
pp. 418-419
Author(s):  
N. Tempel ◽  
M. C. Ledbetter
Keyword(s):  
Electron Microscopy ◽  
High Resolution Electron Microscopy ◽  
Carbon Films ◽  
Low Noise ◽  
Vacuum Evaporation ◽  
High Yield ◽  
Good Adhesion ◽  
Noise Structure ◽  
Resolution Electron ◽  
Carbon Foils

Carbon films have been a support of choice for high resolution electron microscopy since the introduction of vacuum evaporation of carbon. The desirable qualities of carbon films and methods of producing them has been extensively reviewed. It is difficult to get a high yield of grids by many of these methods, especially if virtually all of the windows must be covered with a tightly bonded, quality film of predictable thickness. We report here a method for producing carbon foils designed to maximize these attributes: 1) coverage of virtually all grid windows, 2) freedom from holes, wrinkles or folds, 3) good adhesion between film and grid, 4) uniformity of film and low noise structure, 5) predictability of film thickness, and 6) reproducibility.Our method utilizes vacuum evaporation of carbon from a fiber onto celloidin film and grid bars, adhesion of the film complex to the grid by carbon-carbon contact, and removal of the celloidin by acetone dissolution. Materials must be of high purity, and cleanliness must be rigorously maintained.

Effects of high pressure on the crystallization of carbon fiber reinforced polyetheretherketone (CF/PEEK) laminate composites

1990 ◽  
Vol 48 (4) ◽  
pp. 876-877
Author(s):  
Hong-Ming Lin ◽  
C. H. Liu ◽  
R. F. Lee
Keyword(s):  
High Pressure ◽  
Carbon Fiber ◽  
Sample Surface ◽  
High Yield ◽  
Fiber Reinforced ◽  
Laminate Composites ◽  
Peek Composite ◽  
Continuous Carbon Fiber ◽  
Carbon Fiber Reinforced

Polyetheretherketone (PEEK) is a crystallizable thermoplastic used as composite matrix materials in application which requires high yield stress, high toughness, long term high temperature service, and resistance to solvent and radiation. There have been several reports on the crystallization behavior of neat PEEK and of CF/PEEK composite. Other reports discussed the effects of crystallization on the mechanical properties of PEEK and CF/PEEK composites. However, these reports were all concerned with the crystallization or melting processes at or close to atmospheric pressure. Thus, the effects of high pressure on the crystallization of CF/PEEK will be examined in this study.The continuous carbon fiber reinforced PEEK (CF/PEEK) laminate composite with 68 wt.% of fibers was obtained from Imperial Chemical Industry (ICI). For the high pressure experiments, HIP was used to keep these samples under 1000, 1500 or 2000 atm. Then the samples were slowly cooled from 420 °C to 60 °C in the cooling rate about 1 - 2 degree per minute to induce high pressure crystallization. After the high pressure treatment, the samples were scanned in regular DSC to study the crystallinity and the melting temperature. Following the regular polishing, etching, and gold coating of the sample surface, the scanning electron microscope (SEM) was used to image the microstructure of the crystals. Also the samples about 25mmx5mmx3mm were prepared for the 3-point bending tests.

Catalytic enantioselective synthesis of indolizino[8,7-b]indole alkaloid derivatives based on the tandem reaction of tertiary enamides

2021 ◽  
Author(s):  
Xin-Ming Xu ◽  
Ming Xie ◽  
Jiazhu Li ◽  
Mei-Xiang Wang
Keyword(s):  
Indole Alkaloid ◽  
Enantioselective Synthesis ◽  
High Yield ◽  
Tandem Reaction ◽  
Indole Derivatives

An exquisite Pybox/Cu(OTf)2-catalyzed asymmetric tandem reaction of tertiary enamides was developed, which enabled the expeditious synthesis of indolizino[8,7-b]indole derivatives in high yield, excellent enantioselectivity and diastereoselectivity.

Focus on High-Yield Tests for Running Injuries

2007 ◽  
Vol 40 (10) ◽  
pp. 32
Author(s):  
ROBERT FINN
Keyword(s):  
High Yield ◽  
Running Injuries
Sign in / Sign up

Export Citation Format

Share Document