Aikaterini Ntemka

Dr. Aikaterini Ntemka

orcid

Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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10 August 2020 in Nanomaterials
Verified
Journal Article
Open access
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Ioannis A TsakmakidisIoannis A Tsakmakidis
Ioannis A Tsakmakidis
Theodoros SamarasTheodoros Samaras
Theodoros Samaras
SASofia Anastasiadou
Sofia Anastasiadou
ABAthina Basioura
Athina Basioura
ANAikaterini Ntemka
Aikaterini Ntemka
CBConstantin Boscos
Constantin Boscos
This study examined the effect of Fe3O4 nanoparticles on boar semen. Beltsville thawing solution without antibiotics was used to extend ejaculates from 5 boars (4 ejaculates/boar). Semen samples of control group (C) and group with Fe3O4 (Fe; 0.192 mg/mL semen) were incubated under routine boar semen storage temperature (17 °C) for 0.5 h and nanoparticles were removed by a magnetic field. Before and after treatment, aliquots of all groups were cultured using standard microbiological methods. The samples after treatment were stored (17 °C) for 48 h and sperm parameters (computer-assisted sperm analyzer (CASA) variables; morphology; viability; hypo-osmotic swelling test (HOST); DNA integrity) were evaluated at storage times 0, 24, 48 h. Semen data were analyzed by a repeated measures mixed model and microbial data with Student’s t-test for paired samples. Regarding CASA parameters, Fe group did not differ from C at any time point. In group C, total motility after 24 h and progressive motility after 48 h of storage decreased significantly compared to 0 h. In group Fe, linearity (LIN) after 48 h and head abnormalities after 24 h of storage increased significantly compared to 0 h. The microbiological results revealed a significant reduction of the bacterial load in group Fe compared to control at both 24 and 48 h. In conclusion, the use of Fe3O4 nanoparticles during semen processing provided a slight anti-microbiological effect with no adverse effects on sperm characteristics.

3 April 2021 in Animals
Verified
Journal Article
Open access
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Ioannis A TsakmakidisIoannis A Tsakmakidis
Ioannis A Tsakmakidis
Theodoros SamarasTheodoros Samaras
Theodoros Samaras
SASofia Anastasiadou
Sofia Anastasiadou
ABAthina Basioura
Athina Basioura
ANAikaterini Ntemka
Aikaterini Ntemka
CBConstantin Boscos
Constantin Boscos
The aim of the study was to investigate the effect of iron oxide (Fe) and silver (Ag) nanoparticles (NPs) on ram semen. A skim milk extender without antibiotics was used as a diluent of 21 ejaculates (8 rams; 2–3 ejaculates/ram). The groups of control (C; semen without NPs), Fe NPs (3.072 mg Fe3O4/mL semen), and Ag NPs (2.048 mg Ag-Fe/mL semen) were incubated (15 °C; 30 min), and then a magnetic field was used for NPs’ removal. Standard microbiological procedures were performed for all groups. Post-treated samples were stored (15 °C) for 24 h, and sperm variables (kinetics by computer assisted sperm analysis (CASA); viability; morphology; HOST; DNA integrity) were evaluated at 6 and 24 h. Semen data were analyzed by a mixed model for repeated measures and microbiological data with Student’s t-test for paired samples. At 6 h of storage, VCL and rapid movement-spermatozoa, and at 24 h, total/progressive motility and amplitude of lateral head displacement (ALH) were significantly decreased in group Ag compared to control. In group Fe, progressive/rapid movement-spermatozoa were significantly lower compared to control after 24 h of storage. Only in group Ag was a significant reduction of total bacterial count revealed. In conclusion, the examined Fe NPs demonstrated slight antibacterial effect, while the examined Ag NPs provided higher antibacterial properties accompanied by cytotoxicity.

15 April 2024 in Environmental Pollution
Verified
Journal Article
Closed access
EDEleni Dovolou
Eleni Dovolou
INI. Nanas
I. Nanas
TGThemistoklis Giannoulis
Themistoklis Giannoulis
AFA. Fytsilli
A. Fytsilli
ANAikaterini Ntemka
Aikaterini Ntemka
GAG.S. Amiridis
G.S. Amiridis

30 August 2022 in Animals
Verified
Journal Article
Open access
PDF file
ANAikaterini Ntemka
Aikaterini Ntemka
Ioannis A TsakmakidisIoannis A Tsakmakidis
Ioannis A Tsakmakidis
CBConstantin Boscos
Constantin Boscos
Alexandros  TheodoridisAlexandros Theodoridis
Alexandros Theodoridis
EKEvangelos Kiossis
Evangelos Kiossis
The objective of the current study was to investigate the echotextural and hemodynamic changes of ewes entering the dry period with or without subclinical mastitis. B-mode and color Doppler ultrasonography were applied to 12 Chios ewes (6 with healthy udders (group A) and 6 with subclinical mastitis (group B)) before the dry period, during the dry period (the involution phase, steady state, and transition phase), and postpartum. The color Doppler of the mammary arteries was used to evaluate them according to the pulsatility index (PI), resistive index (RI), end-diastolic velocity (EDV), time-averaged maximum velocity (TAMV), blood flow volume (BFV), and artery diameter (D). Udder parenchyma images, analyzed by Echovet v2.0, were used to evaluate the mean value (MV), standard deviation (SD), gradient mean value (GMV), gradient variance (GV), contrast (Con), entropy (Ent), gray value distribution (GVD), run length distribution (RunLD), and long run emphasis (LRunEm). In the involution phase, the PI was higher in group B compared to group A (p ≤ 0.05). The PI and RI were higher postpartum, whereas the EDV, TAVM, and D were higher in the transition phase (p ≤ 0.05). Neither the period nor the ewe group affected the MV, SD, GMV, GV, Con, and GVD values (p ≤ 0.05). In the steady state, the LRunEm was higher in group B, but postpartum, it was higher in group A (p ≤ 0.05). In conclusion, B-mode and Doppler can reveal differences (i) between healthy ewes and ewes with subclinical mastitis and (ii) among the different periods studied. Further research is needed on the blood flow and echotexture indices of the udders of ewes with unilateral subclinical mastitis.

8 May 2026 in Journal of the Hellenic Veterinary Medical Society
Verified
Journal Article
Open access
ANAikaterini Ntemka
Aikaterini Ntemka
Ioannis A TsakmakidisIoannis A Tsakmakidis
Ioannis A Tsakmakidis
EKE Kiossis
E Kiossis
Systematic evaluation of male reproductive capacity ensures fertility, enhancing the economics of small ruminant farms. The evaluation of semen quality via contemporary and objective laboratory techniques contributes to the assessment of sperm fertilizing ability, while in combination with the animals’ clinical examination, supports the prognosis of ram/buck fertility. B-mode and Doppler ultrasonographic examination of male reproductive system can be applied in addition to clinical examination, since various non clinically identified pathological conditions adversely affect fertility. In the past 20 years, many researchers indicated a variable but notable correlation between seminal quality and B-mode and Doppler ultrasonographic indices in small ruminants. The present review was aimed at providing updated knowledge on the prospect of applying B-mode and Doppler ultrasonographic examination to assist ram and buck fertilizing ability evaluation.