Identification of sperm morphometric subpopulations in the canine
                    ejaculate: do they reflect different subpopulations in sperm chromatin
                    integrity?

SummaryA statistical approach using sequentially principal component analysis (PCA) clustering and discriminant analysis was developed to disclose morphometric sperm subpopulations. In addition, we used a similar approach to disclose subpopulations of spermatozoa with different degrees of DNA fragmentation. It is widely accepted that sperm morphology is a strong indicator of semen quality and since the sperm head mainly comprises the sperm DNA, it has been proposed that subtle changes in sperm head morphology may be related to abnormal DNA content. Semen from four mongrel dogs (five replicates per dog) were used to investigate DNA quality by means of the sperm chromatin structure assay (SCSA), and for computerized sperm morphometry (ASMA). Each sperm head was measured for nine primary parameters: head area (A), head perimeter (P), head length (L), head width (W), acrosome area (%), midpiece width (w), midpiece area (a), distance (d) between the major axes of the head and midpiece, angle (θ) of divergence of the midpiece from the head axis; and four parameters of head shape: FUN1 (L/W), FUN2 (4π A/P2), FUN3 ((L – W)/(L + W)) and FUN 4 (π LW/4A). The data matrix consisted of 2361 observations, (morphometric analysis on individual spermatozoa) and 63 815 observations for the DNA integrity. The PCA analysis revealed five variables with Eigen values over 1, representing more than 79% of the cumulative variance. The morphometric data revealed five sperm subpopulations, while the DNA data gave six subpopulations of spermatozoa with different DNA integrity. Significant differences were found in the percentage of spermatozoa falling in each cluster among dogs (p < 0.05). Linear regression models including sperm head shape factors 2, 3 and 4 predicted the amount of denatured DNA within each individual spermatozoon (p < 0.001). We conclude that the ASMA analysis can be considered a powerful tool to improve the spermiogram.

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Sexual selection on protamine and transition nuclear protein expression in mouse species

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2013.3359 ◽

2014 ◽

Vol 281 (1783) ◽

pp. 20133359 ◽

Cited By ~ 16

Author(s):

Lena Lüke ◽

Polly Campbell ◽

María Varea Sánchez ◽

Michael W. Nachman ◽

Eduardo R. S. Roldan

Keyword(s):

Sexual Selection ◽

Sperm Competition ◽

Nuclear Protein ◽

Sperm Head ◽

Nuclear Proteins ◽

Sperm Chromatin ◽

Head Shape ◽

Mouse Species ◽

The Relationship ◽

Protamine 2

Post-copulatory sexual selection in the form of sperm competition is known to influence the evolution of male reproductive proteins in mammals. The relationship between sperm competition and regulatory evolution, however, remains to be explored. Protamines and transition nuclear proteins are involved in the condensation of sperm chromatin and are expected to affect the shape of the sperm head. A hydrodynamically efficient head allows for fast swimming velocity and, therefore, more competitive sperm. Previous comparative studies in rodents have documented a significant association between the level of sperm competition (as measured by relative testes mass) and DNA sequence evolution in both the coding and promoter sequences of protamine 2. Here, we investigate the influence of sexual selection on protamine and transition nuclear protein mRNA expression in the testes of eight mouse species that differ widely in levels of sperm competition. We also examined the relationship between relative gene expression levels and sperm head shape, assessed using geometric morphometrics. We found that species with higher levels of sperm competition express less protamine 2 in relation to protamine 1 and transition nuclear proteins. Moreover, there was a significant association between relative protamine 2 expression and sperm head shape. Reduction in the relative abundance of protamine 2 may increase the competitive ability of sperm in mice, possibly by affecting sperm head shape. Changes in gene regulatory sequences thus seem to be the basis of the evolutionary response to sexual selection in these proteins.

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Are semen quality parameters sufficient for biomonitoring spermatozoa DNA integrity and oxidatively damaged DNA

Biomonitoring ◽

10.1515/bimo-2015-0004 ◽

2015 ◽

Vol 2 (1) ◽

Author(s):

Hueiwang Anna Jeng ◽

Ruei-Nian Li ◽

Wen-Yi Lin

Keyword(s):

Dna Damage ◽

Dna Fragmentation ◽

Semen Quality ◽

Quality Parameters ◽

Semen Parameters ◽

Sperm Chromatin ◽

Dna Integrity ◽

Phase System ◽

Sperm Dna Fragmentation ◽

Sperm Dna

Abstract:The present study aimed to investigate the relationship between semen quality parameters and DNA integrity, and determine whether semen quality parameters could serve as a reliable biomarker for monitoring sperm DNA damage. Conventional semen parameters from a total of 202 male human subjects were analyzed. DNA fragmentation and 8-oxo-7,8-dihydro-2′- deoxyguanosine (8-oxoGuo) were used to assess sperm DNA integrity. DNA fragmentation was analyzed by the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay and sperm chromatin structure assay (SCSA), while 8-oxodGuo was quantified by the liquid chromatography/tandem mass spectrometry (LC-MS/MS) coupled with an on-line solid phase system. The levels of 8-oxodGuo levels in sperm were related to the percentages of DNA fragmentation measured by both the TUNEL and SCSA (r = 0.22, p = 0.048; r = 0.12, p = 0.039). Sperm vitality, motility and morphology from all of the participants exhibited a weak correlation with the levels of 8-oxodGuo and the percentages of DNA fragmentation. Semen quality parameters may be independent of the formation of DNA fragmentation and oxidative adducts in sperm. Semen quality parameters may be insufficient to monitor sperm DNA fragmentation and oxidative damage. DNA damage in sperm is recommended to be included in routine measurements.

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Sperm DNA Integrity Assessment: A New Tool in Diagnosis and Treatment of Fertility

Obstetrics and Gynecology International ◽

10.1155/2012/531042 ◽

2012 ◽

Vol 2012 ◽

pp. 1-6 ◽

Cited By ~ 36

Author(s):

Mona Bungum

Keyword(s):

Semen Quality ◽

Significant Proportion ◽

Semen Parameters ◽

Sperm Chromatin ◽

Dna Integrity ◽

Sperm Dna Fragmentation ◽

Integrity Assessment ◽

Sperm Dna Integrity ◽

Sperm Dna

Infertility affects 15% of all couples. Although male infertility factors with reduced semen quality are contributing to about half of all involuntary childlessness, the value of standard semen parameters in prediction of fertilityin vivoand choice of proper method for assisted reproduction is limited. In the search for better markers of male fertility, during the last 10 years, assessment of sperm DNA integrity has emerged as a strong new biomarker of semen quality that may have the potential to discriminate between infertile and fertile men. Sperm DNA Fragmentation Index (DFI) as assessed by the flow cytometric Sperm Chromatin Structure Assay (SCSA) can be used for evaluation of sperm chromatin integrity. The biological background for abnormal DFI is not completely known, but clinical data show that DFI above 30% is associated with very low chance for achieving pregnancy in natural way or by insemination, but notin vitro. Already when the DFI is above 20%, the chance of natural pregnancy may be reduced, despite other sperm parameters being normal. Thus this method may explain a significant proportion of cases of unexplained infertility and can be beneficial in counselling involuntary childless couples need ofin vitrofertilisation.

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Spermatogenic Activity and Sperm Traits in Post-Pubertal and Adult Tomcats (Felis catus): Implication of Intra-Male Variation in Sperm Size

Cells ◽

10.3390/cells10030624 ◽

2021 ◽

Vol 10 (3) ◽

pp. 624

Author(s):

Eliana Pintus ◽

Martin Kadlec ◽

Barbora Karlasová ◽

Marek Popelka ◽

José Luis Ros-Santaella

Keyword(s):

Cell Function ◽

Sperm Quality ◽

Sperm Concentration ◽

Sperm Head ◽

Mitochondrial Activity ◽

Head Width ◽

Dna Integrity ◽

One Year ◽

Sperm Size ◽

Sperm Traits

Tomcats are considered to be adults at 1 year of age, although many reach sexual maturity at an earlier age. Nevertheless, we still know little about whether the spermatogenic activity and sperm quality of mature under one-year-old tomcats differ from those of tomcats that are over one-year-old. This study aims to evaluate the spermatogenic activity, sperm traits, and their relationships in mature tomcats at two different ages. Sixteen tomcats showing complete spermatogenesis and spermatozoa in their epididymal caudae were used and classified according to their age as post-pubertal (<1 year old) or adult (˃1 year old). Our results show that adult cats have higher epididymal sperm concentration and lower coefficient of variation in sperm head width and ellipticity than post-pubertal cats. However, they do not differ in their testicular and epididymal mass, spermatogenesis, and sperm traits such as motility, mitochondrial activity, morphology, morphometry, as well as plasma membrane, acrosome, and DNA integrity. Reduced intra-male variation of sperm head ellipticity is associated with higher testis mass, epididymis mass, and sperm concentration. Interestingly, low intra-male variation in sperm head size is associated with increased Sertoli cell function and reduced post-meiotic germ cell loss. These findings increase our knowledge about feline reproductive physiology and provide new insights into the functional significance of low intra-male variation in sperm size and shape in tomcats.

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Bull and boar sperm DNA integrity evaluated by sperm chromatin structure assay in the Czech Republic

Veterinární Medicína ◽

10.17221/5668-vetmed ◽

2012 ◽

Vol 49 (No. 1) ◽

pp. 1-8

Author(s):

R. Rybak ◽

L. Faldikova ◽

M. Faldyna ◽

M. Machatkova ◽

J. Rubes

Keyword(s):

Chromatin Structure ◽

Semen Quality ◽

Farm Animals ◽

Sperm Chromatin ◽

Dna Integrity ◽

Sperm Dna Damage ◽

Sperm Chromatin Structure Assay ◽

Sperm Dna ◽

Boar Sperm ◽

Reproductive Techniques

Analysis of sperm parameters is very important for predicting the outcome of assisted reproductive techniques and is necessary for determination of fertility potential of males tested for artificial insemination. In our study we have determined the level of bull and boar sperm DNA damage by Sperm Chromatin Structure Assay (SCSA). This test is based on increased susceptibility of altered DNA (strand breaks) in sperm nuclear chromatinto in situ denaturation measured by flow cytometry after staining with acridine orange (AO). Sperm chromatin damage was quantified by percentages of spermatozoa with detectable DNA Fragmentation Index – DFI divided into moderate (m-DFI) and high (h-DFI) DFI. Percentage of immature cells (HDS; cells with High DNA Stainability) was also evaluated. We measured sperm SCSA parameters in a total of 37 bulls in two groups from different localities and 68 boar samples from one locality. Significantly higher percentage of spermatozoa with detectable DFI was detected in six bulls (16.2%) and a significantly higher percentage of immature cell forms (HDS) was found in other six bulls (16.2%) among all tested bulls. The mean percentages of spermatozoa with h-DFI and HDS of bulls from the second group were statistically higher than those from the first group (P < 0.01). Five boars (7.4%) of all tested boars had significantly higher percentage of spermatozoa with DFI and 18 boars (26.5%) had significantly higher percentage of sperm with HDS compared to the other boars. Both percentages of spermatozoa with DFI and HDS were significantly higher in one boar compared to the others. Boars had significantly higher percentages of spermatozoa with h-DFI and HDS (P < 0.0001) in comparison to bulls. For individual bulls, the highest percentages of spermatozoa with DFI and HDS were 20.8% and 3.5%, respectively while for boars these were 17.6% and 10.2%, respectively. No significant correlations were found between percentages of spermatozoa with DFI and HDS. This sensitive procedure seems to be convenient as additional method for semen quality detection in farm animals before their exploitation in breeding.

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Cardiorespiratory fitness is positively associated with both healthy and western dietary pattern in Iranian middle-aged

International Journal for Vitamin and Nutrition Research ◽

10.1024/0300-9831/a000685 ◽

2020 ◽

pp. 1-10

Author(s):

Hossein Shahinfar ◽

Farhang Djafari ◽

Nadia Babaei ◽

Samira Davarzani ◽

Mojdeh Ebaditabar ◽

...

Keyword(s):

Cardiorespiratory Fitness ◽

Dietary Patterns ◽

Dietary Pattern ◽

Principal Component ◽

Total Sample ◽

Linear Regression Models ◽

Middle Aged ◽

Anthropometric Measures ◽

Western Dietary Pattern ◽

Healthy Dietary Pattern

Abstract. Background: The association between dietary patterns and cardiorespiratory fitness (CRF) is not well established. Objective: We sought to investigate association between a posteriori dietary pattern and CRF in middle-aged adults. Design: Adults (n = 276), aged 20–74 years, who were residents of Tehran, Iran were recruited. Diet was assessed by using a validated 168-item semi-quantitative food frequency questionnaire. Principal component analysis was used to derive dietary patterns. Socio-economic status, anthropometric measures, body composition, and blood pressure were recorded. CRF was assessed by using a graded exercise treadmill test. Analysis of variance and linear regression models were used to discern the association between dietary patterns and CRF. Results: Higher scores of the healthy dietary pattern had no association with VO2max (p = 0.13 ). After controlling for potential confounders, VO2max was positively associated across tertiles of healthy dietary patterns (p < 0.001). Higher adherence to the “mixed” dietary pattern was inversely related to VO2max (p < 0.01). After adjusting for confounders, the significant association disappeared (p = 0.14). Higher scores of the “Western” dietary pattern was not associated with VO2max (p = 0.06). However, after controlling for potential confounders, VO2max was positively associated with the “Western” dietary pattern (p = 0.01). A positive linear association between the “healthy” dietary pattern and CRF for the total sample (R2 = 0.02; p < 0.01) were presented. Conclusions: Overall, our findings suggest that higher adherence to a “healthy” and “Western” dietary pattern was positively associated with CRF. However, further studies are required to examine and clarify the causal relationship between dietary patterns and CRF.

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Principal component analysis of substituent constants

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19900055 ◽

1990 ◽

Vol 55 (1) ◽

pp. 55-62 ◽

Cited By ~ 1

Author(s):

Drahomír Hnyk

Keyword(s):

Principal Component Analysis ◽

Inductive Effect ◽

Resonance Effect ◽

Principal Component ◽

Component Analysis ◽

Total Variance ◽

Data Matrix ◽

Cumulative Proportion ◽

Two Factors ◽

Substituent Constants

The principal component analysis has been applied to a data matrix formed by 7 usual substituent constants for 38 substituents. Three factors are able to explain 99.4% cumulative proportion of total variance. Several rotations have been carried out for the first two factors in order to obtain their physical meaning. The first factor is related to the resonance effect, whereas the second one expresses the inductive effect, and both together describe 97.5% cumulative proportion of total variance. Their mutual orthogonality does not directly follow from the rotations carried out. With the help of these factors the substituents are divided into four main classes, and some of them assume a special position.

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A Novel Validated Injectable Colistimethate Sodium Analysis Combining Advanced Chemometrics and Design of Experiments

Molecules ◽

10.3390/molecules26061546 ◽

2021 ◽

Vol 26 (6) ◽

pp. 1546

Author(s):

Ioanna Dagla ◽

Anthony Tsarbopoulos ◽

Evagelos Gikas

Keyword(s):

Design Of Experiments ◽

High Performance ◽

Similarity Index ◽

Principal Component ◽

Partial Least Square ◽

Least Square ◽

Partial Least Square Regression ◽

Distance Measures ◽

Linear Regression Models ◽

Colistimethate Sodium

Colistimethate sodium (CMS) is widely administrated for the treatment of life-threatening infections caused by multidrug-resistant Gram-negative bacteria. Until now, the quality control of CMS formulations has been based on microbiological assays. Herein, an ultra-high-performance liquid chromatography coupled to ultraviolet detector methodology was developed for the quantitation of CMS in injectable formulations. The design of experiments was performed for the optimization of the chromatographic parameters. The chromatographic separation was achieved using a Waters Acquity BEH C8 column employing gradient elution with a mobile phase consisting of (A) 0.001 M aq. ammonium formate and (B) methanol/acetonitrile 79/21 (v/v). CMS compounds were detected at 214 nm. In all, 23 univariate linear-regression models were constructed to measure CMS compounds separately, and one partial least-square regression (PLSr) model constructed to assess the total CMS amount in formulations. The method was validated over the range 100–220 μg mL−1. The developed methodology was employed to analyze several batches of CMS injectable formulations that were also compared against a reference batch employing a Principal Component Analysis, similarity and distance measures, heatmaps and the structural similarity index. The methodology was based on freely available software in order to be readily available for the pharmaceutical industry.

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