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Comparative Biochemistry and... Jun 2022Emerging pollutants (EPs) are causative for teratogenic and reproductive effects. EPs are detected in all the environmental matrices at higher levels. A suitable model... (Review)
Review
Emerging pollutants (EPs) are causative for teratogenic and reproductive effects. EPs are detected in all the environmental matrices at higher levels. A suitable model for aquatic toxicity assessment is Hydra, because of morphological, behavioral, reproductive (sexual and asexual), and biochemical changes. Many researchers have used Hydra for toxicity assessment of organic chemicals (BPA), heavy metals, pharmaceuticals, nanomaterials and microplastics. Various Hydra species were used for environmental toxicity studies; however H. magnipapillata was predominantly used due to the availability of its genome and proteome sequences. Teratogenic and reproductive changes in Hydra are species specific. Teratogenic effects were studied using sterozoom dissecting microscope, acridine orange (AO) and 4',6-diamidino-2-phenylindole (DPAI) staining. Reactive oxygen species (ROS) generation by EPs had been understood by the Dichlorodihydrofluorescein Diacetate (DCFDA) staining and comet assay. Multiple advanced techniques would aid to understand the effects at molecular level, such as real-time PCR, rapid amplification of cDNA end- PCR. EPs modulated the major antioxidant enzyme levels, therefore, defense mechanism was affected by the higher generation of reactive oxygen species. Genome sequencing helps to know the mode of action of pollutants, role of enzymes in detoxification, defense genes and stress responsive genes. Molecular techniques were used to obtain the information for evolutionary changes of genes and modulation of gene expression by EPs.
Topics: Animals; Hydra; Microplastics; Models, Animal; Reactive Oxygen Species; Water Pollutants, Chemical
PubMed: 35227876
DOI: 10.1016/j.cbpc.2022.109320 -
Cell Biology International Nov 2023Breast cancer is a commonly known cancer type and the leading cause of cancer death among females. One of the unresolved problems in cancer treatment is the increased... (Review)
Review
Breast cancer is a commonly known cancer type and the leading cause of cancer death among females. One of the unresolved problems in cancer treatment is the increased resistance of the tumor to existing treatments, which is a direct result of apoptotic defects. Calculating an alternative to cell death (autophagy) may be the ultimate solution to maximizing cancer cell death. Our aim in this study was to investigate the potential of free nanoparticles (un-drug-loaded) in the induction or inhibition of autophagy and consider this effect on the therapy process. When the studies met the inclusion criteria, the full texts of all relevant articles were carefully examined and classified. Of the 25 articles included in the analysis, carried out on MCF-7, MDA-MB-231, MDA-MB-231-TXSA, MDA-MB-468, SUM1315, and 4T1 cell lines. Twenty in vitro studies and five in vivo/in vitro studies applied five different autophagy tests: Acridine orange, western blot, Cyto-ID Autophagy Detection Kit, confocal microscope, and quantitative polymerase chain reaction. Nanoparticles (NPs) in the basic format, including Ag, Au, Y O , Se, ZnO, CuO, Al, Fe, vanadium pentoxide, and liposomes, were prepared in the included articles. Three behaviors of NPs related to autophagy were seen: induction, inhibition, and no action. Screened and presented data suggest that most of the involved free NPs (metallic NPs) in this systematic review had reactive oxygen species-mediated pathways with autophagy induction (36%). Also, PI3K/Akt/mTOR and MAPK/ERK signaling pathways were mentioned in just four studies (16%). An impressive percentage of studies (31%) did not examine the NP-related autophagy pathway.
PubMed: 37671447
DOI: 10.1002/cbin.12081 -
Human Reproduction (Oxford, England) Oct 2012Is there an association between high levels of sperm DNA damage and miscarriage? (Meta-Analysis)
Meta-Analysis Review
STUDY QUESTION
Is there an association between high levels of sperm DNA damage and miscarriage?
SUMMARY ANSWER
Miscarriage rates are positively correlated with sperm DNA damage levels.
WHAT IS KNOWN ALREADY
Most ejaculates contain a subpopulation of sperm with DNA damage, also referred to as DNA fragmentation, in the form of double or single-strand breaks which have been induced in the DNA prior to or following ejaculation. This DNA damage may be particularly elevated in some subfertile men, hence several studies have examined the link between sperm DNA damage levels and conception and miscarriage rates.
STUDY DESIGN, SIZE, DURATION
A systematic review and meta-analysis of studies which examined the effect of sperm DNA damage on miscarriage rates was performed. Searches were conducted on MEDLINE, EMBASE and the Cochrane Library without any language restrictions from database inception to January 2012.
PARTICIPANTS/MATERIALS, SETTING, METHODS
We used the terms 'DNA damage' or 'DNA fragmentation' combined with 'miscarriage', 'abortion' or 'pregnancy' to generate a set of relevant citations. Data extraction was performed by two reviewers. Study quality was assessed using the Newcastle-Ottawa Scale. Meta-analysis of relative risks of miscarriage was performed with a random effects model. Subgroup analyses were performed by the type of DNA damage test, whether the sperm examined were prepared or from raw semen and for pregnancies resulting from IVF or ICSI treatment.
MAIN RESULTS AND THE ROLE OF CHANCE
We identified 16 cohort studies (2969 couples), 14 of which were prospective. Eight studies used acridine orange-based assays, six the TUNEL assay and two the COMET assay. Meta-analysis showed a significant increase in miscarriage in patients with high DNA damage compared with those with low DNA damage [risk ratio (RR) = 2.16 (1.54, 3.03), P < 0.00001)]. A subgroup analysis showed that the miscarriage association is strongest for the TUNEL assay (RR = 3.94 (2.45, 6.32), P < 0.00001).
LIMITATIONS, REASONS FOR CAUTION
There is some variation in study characteristics, including the use of different assays and different thresholds for DNA damage and the definition of pregnancy loss.
WIDER IMPLICATIONS OF THE FINDINGS
The use of methods which select sperm without DNA damage for use in assisted conception treatment may reduce the risk of miscarriage. This finding indicates that assays detecting DNA damage could be considered in those suffering from recurrent pregnancy loss. Further research is necessary to study the mechanisms of DNA damage and the potential therapeutic effects of antioxidant therapy.
STUDY FUNDING/COMPETING INTEREST(S)
None.
Topics: Abortion, Spontaneous; Cohort Studies; Comet Assay; DNA Fragmentation; Female; Fertilization in Vitro; Humans; In Situ Nick-End Labeling; Male; Odds Ratio; Pregnancy; Risk Assessment; Sperm Injections, Intracytoplasmic; Spermatozoa; United States
PubMed: 22791753
DOI: 10.1093/humrep/des261 -
The Lancet. Infectious Diseases Sep 2006The accuracy of techniques for the diagnosis of malaria are usually compared with optical microscopy, which is considered to be a gold standard. However, microscopy is... (Review)
Review
The accuracy of techniques for the diagnosis of malaria are usually compared with optical microscopy, which is considered to be a gold standard. However, microscopy is prone to error and therefore makes it difficult to assess the reliability of other diagnostic techniques. We did a systematic review to assess the specificity and sensitivity of diagnostic techniques in different settings, using a statistical method that avoided defining a gold standard. Performance varied depending on species of the malaria parasite, level of parasitaemia, and immunity. Overall, histidine-rich protein 2 (HRP2)-based dipsticks showed a high sensitivity (92.7%) and specificity (99.2%) for Plasmodium falciparum in endemic areas. The acridine orange test was more sensitive (97.1%) in detecting P falciparum in epidemiological studies, with a specificity of 97.9%. In the absence of a gold standard, HRP2 dipsticks and acridine orange could provide an alternative for detecting falciparum infections in endemic areas and epidemiological studies, respectively. Microscopy still remains more reliable in detecting non-falciparum infections.
Topics: Animals; Humans; Malaria; Microscopy; Patient Selection; Plasmodium; Reproducibility of Results; Sensitivity and Specificity
PubMed: 16931409
DOI: 10.1016/S1473-3099(06)70579-5 -
Journal of Gynecology Obstetrics and... Apr 2020A high sperm DNA fragmentation index (DFI) influences human reproduction and is observed in infertile men. However, the influence of DFI on unexplained recurrent... (Review)
Review
BACKGROUND
A high sperm DNA fragmentation index (DFI) influences human reproduction and is observed in infertile men. However, the influence of DFI on unexplained recurrent spontaneous abortion (RSA) remains controversial.
OBJECTIVE
We explored the influence of DFI on unexplained recurrent spontaneous abortion.
DATA SOURCES
We conducted a meta-analysis of DFI (assessed by sperm chromatin structure assay(SCSA), terminal deoxynucleotidyl transferase-mediated deoxyuridine (TdT)triphosphate (dUTP) nick end labeling assay(TUNEL), sperm chromatin dispersion(SCD), single cell gel electrophoresis assay(COMET assay), and acridine orange test(AOT) with unexplained RSA from the Cochrane Library, EMBASE, Pubmed and Web of Science database.
METHODS
Records were screened for eligible studies and data were extracted to an online data extraction form. The main outcome was the sperm DFI. Summary measures were reported as the mean difference(MD) and Odds Ratio(OR) with 95 % confifidence interval (CI).
RESULT
We identified 27 articles including 3, 2, 9, 9, and 8 studies using AO, COMET, SCSA, SCD and TUNEL respectively; 7 articles used qualitative methods and 21 articles used in quantitative methods. The combined MD estimates of 7 SCSA studies (MD=5.4; 95 % CI: 1.76-9.03; P<0.01), 9 SCD studies (MD=11.16; 95 % CI:6.70-15.62; P<0.01), and 8 TUNEL studies (MD=12.12; 95 % CI: 3.34-20.91; P<0.01) showed significant differences. Notably, qualitative studies showed consistent results with quantitative studies.
CONCLUSION(S)
These findings support an association between sperm DFI and recurrent pregnancy loss. Previous studies revealed that DFI negatively impacts unexplained RSA.
PubMed: 32348878
DOI: 10.1016/j.jogoh.2020.101740 -
Arab Journal of Urology Mar 2018To review sperm DNA fragmentation (SDF) testing as an important sperm function test in addition to conventional semen analysis. High SDF is negatively associated with...
OBJECTIVE
To review sperm DNA fragmentation (SDF) testing as an important sperm function test in addition to conventional semen analysis. High SDF is negatively associated with semen quality, the fertilisation process, embryo quality, and pregnancy outcome. Over recent decades, different SDF assays have been developed and reviewed extensively to assess their applicability and accuracy as advanced sperm function tests. Amongst them, the standardisation of the terminal deoxynucleotidyl transferased UTP nick-end labelling (TUNEL) assay with a bench top flow cytometer in clinical practice deserves special mention with a threshold value of 16.8% to differentiate infertile men with DNA damage from fertile men.
MATERIALS AND METHODS
A systematic literature search was performed through the PubMed, Medline, and ScienceDirect databases using the keywords 'sperm DNA fragmentation' and 'laboratory assessment'. Non-English articles were excluded and studies related to humans were only included.
RESULTS
Of the 618 identified, 87 studies (original research and reviews) and in addition eight book chapters meeting the selection criteria were included in this review. In all, 366 articles were rejected in the preliminary screening and a further 165 articles related to non-human subjects were excluded.
CONCLUSION
There are pros and cons to all the available SDF assays. TUNEL is a reliable technique with greater accuracy and as an additional diagnostic test in Andrology laboratories along with basic semen analysis can predict fertility outcome, and thus direct the choice of an assisted reproductive technology procedure for infertile couples. Also, the TUNEL assay can be used as a prognostic test and results are beneficial in deciding personalised treatment for infertile men.
PubMed: 29713537
DOI: 10.1016/j.aju.2017.12.001