Methods for Sperm Concentration Determination

Author(s):  
Lars Björndahl
Author(s):  
M. Haider ◽  
B. Bohrmann

The technique of Z-contrast in STEM offers the possibility to determine the local concentration of macromolecules like lipids, proteins or DNA. Contrast formation depends on the atomic composition of the particular structure. In the case of DNA, its phosphorous content discriminates it from other biological macromolecules. In our studies, sections of E. coli, the dinoflagellate Amphidinium carterae and Euglena spec. cells were used which were obtained by cryofixation followed by freeze-substitution into acetone with 3% glutaraldehyde. The samples were then embedded either in Lowicryl HM20 at low temperature or in Epon at high temperature. Sections were coated on both sides with 30Å carbon.The DF- and the inelastic image have been recorded simultaneously with a Cryo-STEM. This Cryo-STEM is equipped with a highly dispersive Electron Energy Loss Spectrometer. With this instrument pure Z-contrast can be achieved either with a Filtered DF-image divided by the inelastic image or, as is used in this paper, by dividing the conventional DF-image by an inelastic image which has been recorded with an inelastic detector whose response is dependent on the total energy loss of the inelastically scattered electrons.


2016 ◽  
pp. 51-56
Author(s):  
Thi Le Thuy Nguyen ◽  
Thanh Sinh Do ◽  
Thi Hoa Tran

Backgroud: Gac is a fruit containing many antioxidants, especially lycopene, with high concentration. However the variety and value of products from gac are limited. We introduce a modified method to produce lycopene and others carotenoids from gac oil towards available and safe applications in nutraceutical and cosmetics. Materials and method: We study the extraction with different parameters and limit at the saponification of gac oil using less toxic substances such as ethanol, propylene glycol, postasium hydroxide and sodium chlorid. Results: Concentrations of lycopene and β-carotene determined silmutaneously by UVVis spectrophotometer present that the efficiency reaches 65.07% as 20 g of gac oil is saponified with 8 g KOH 12 mol/L in 120 mins. The purity of product is 89.02%. Conclusions: This process could minimize toxic residue in the powder after the precipitation, filtration and washing. Besides, the method is stable and applicable to the mass production. Key words: Carotenoids, Lycopene, safe extraction, UV Vis silmutaneous concentration determination


Author(s):  
Thea Emily Benson ◽  
Anne Gaml-Sørensen ◽  
Andreas Ernst ◽  
Nis Brix ◽  
Karin Sørig Hougaard ◽  
...  

Bisphenol A (BPA) is considered an endocrine disruptor and has been associated with deleterious effects on spermatogenesis and male fertility. Bisphenol F (BPF) and S (BPS) are structurally similar to BPA, but knowledge of their effects on male fertility remains limited. In this cross–sectional study, we investigated the associations between exposure to BPA, BPF, and BPS and semen quality in 556 men 18–20 years of age from the Fetal Programming of Semen Quality (FEPOS) cohort. A urine sample was collected from each participant for determination of BPA, BPF, and BPS concentrations while a semen sample was collected to determine ejaculate volume, sperm concentration, total sperm count, sperm motility, and sperm morphology. Associations between urinary bisphenol levels (continuous and quartile–divided) and semen characteristics were estimated using a negative binomial regression model adjusting for urine creatinine concentration, alcohol intake, smoking status, body mass index (BMI), fever, sexual abstinence time, maternal pre–pregnancy BMI, and first trimester smoking, and highest parental education during first trimester. We found no associations between urinary bisphenol of semen quality in a sample of young men from the general Danish population.


Aquaculture ◽  
2021 ◽  
pp. 736682
Author(s):  
João Pedro Nascimento ◽  
Yevhen Horokhovatskyi ◽  
Vitaliy Kholodnyy ◽  
Marek Rodina ◽  
Viktoriya Dzyuba ◽  
...  
Keyword(s):  

2021 ◽  
Vol 26 (1) ◽  
Author(s):  
Indu Sharma ◽  
Priti Kumari ◽  
Anuradha Sharma ◽  
Subhas Chandra Saha

Abstract Background COVID-19 is the most recent zoonotic outbreak of coronaviruses. Mostly, it invades the cells of the respiratory system by binding to the receptor angiotensin-converting enzyme 2 (ACE2) which is also present in other organs like the kidney, testis, ovaries, breast, heart, and intestine, rendering them prone to be infected. The reproductive potential is a must for the sustenance of any species and it is our prime duty to safeguard the reproductive system of the present generation from such a deadly virus. The previously reported coronaviruses like severe acute respiratory syndrome coronavirus (SARS-CoV) had a detrimental impact on reproductive organs. There is a dearth of sufficient research to provide substantial evidence for the harmful effects of this novel virus on the reproductive system. Hence, our review compiles the knowledge available until now to boost research in this regard and to take the necessary steps in time. Main body of abstract Here we tried to compile all the data available on the effect of SARS-CoV-2 on the reproductive system as well as vertical transmission of the virus. All related articles published from February to August 2020 were reviewed and thoroughly analyzed. SARS-CoV-2 has been found to affect the sperm concentration and motility, thus degrading the fertility of males. In females, it is suspected that this virus affects the oocyte quality and ovarian function, resulting in infertility or miscarriage. Traces of SARS-CoV-2 virus have also been found in the breast milk of the infected mothers and the semen of infected males. Vertical transmission of SARS-CoV-2 has also been reported in some cases. Conclusion Based on the literature review, SARS-CoV-2 seems to have the potential of affecting both male and female reproductive tracts. This review brings together the findings and observations made in the area of reproductive health during the current pandemic. The reproductive system of the young population is preordained for subsequent disorders, infertility, reduced sperm count, and motility. Therefore, the research and medical practices should focus on possible vulnerability being posed by SARS-CoV-2 to the gametes and future generations. We, hereby, recommend close monitoring of young and pregnant COVID-19 patients concerning reproductive health with utmost priority.


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