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The Effects of Tobacco and Cannabis Consuming on Male Fertility: A Comprehensive Analysis of Sperm Quality, Chromatin integrity, Genetic Variations, and Oxidative Stress
Get PDFRecent comprehensive meta-analysis research has uncovered a notable reduction in sperm concentration and total sperm counts among men from North America, Europe, and Australia between 1973 and 2011. This decline, estimated at 50–60%, affects men regardless of their fertility status, with no signs of stabilization in recent years. These findings strongly suggest a significant deterioration in male reproductive health, with implications that extend beyond fertility concerns (Levine H et al., 2017). Given the magnitude of this global shift, the most compelling explanation is one that universally affects all populations involved. There is no doubt about the significant impact that new lifestyle changes can have on us.
It is well-documented that tobacco smoking adversely affects a broad spectrum of physiological functions. Additionally, the use of tobacco and cannabis presents an escalating threat to male reproductive health. Although the prevalence of tobacco smoking declined over time among men in reproductive age, the use of other inhaled products, such as cannabis have increased. Therefore, understanding their potential deleterious effects on male fertility is crucial for the well-being of future generations.
Numerous studies over recent decades have indicated a correlation between smoking tobacco or cannabis and a decline in sperm quality, potentially leading to male infertility. Tobacco smoking, a widespread global occurrence, considerably impacts not only an individual's well-being but also their genetic makeup. Over the past few years, comprehensive research has explored the intricate relationship between tobacco exposure and the expression of numerous genes. Recently cannabis consuming has shifted following the legislation of marijuana in various countries and states, an imperative public health concern has emerged that affect not only to users but also to their offspring.
The perception of Cannabis toxicity and safety in society, politics, and even scientific circles has changed dramatically in recent decade. Consequently, a few questions have been raised regarding the effects of marijuana (Cannabis sativa) on human physiology and reproductive health in the short and long term.
Therefore, the purpose of this study was to determine the effects of tobacco and cannabis use on sperm quality, chromatin integrity, and oxidative damage among men Previously engaged in annual use of tobacco or cannabis. And to investigate, nonetheless, the damage that tobacco and cannabis and their constituents on sperm mitochondrial genetic variants in the Cytochrome C Oxidase 1, 2 and 3 genes (MT-CO1, MT-CO2, and MT-CO3). Specifically on the alterations in the cytochrome oxidase encoded gene present within sperm mitochondria.
Initially, 10 semen samples have undergone an in Vitro study by analyzing semen parameters (volume, sperm count, motility), within 1 hour after collection, according to WHO criteria 2020. For accurate results, Computer Assisted Sperm Analysis (CASA) system was used to determine sperm parameters. Each sample was exposed to 1 mL; 10 µg/mL of THC, THC-COOH, and CBD dissolved in methanol. All samples were also exposed to 1 mL pure methanol as a control group to eliminate the potential effects of methanol on sperm cells. Several smears (10 µL) of each sample were taken in order to assess the functionality of sperm’s chromatin integrity by employing a Chromomycin (CMA3) and DNA fragmentation (Acridine Orange) assays.
Then, a total of 116 samples were collected from men aged less than 40 years at Prince Rashid Bin Al Hassan Hospital (PRBH) in Irbid, Jordan. The samples were divided into three groups: Group 1 - Non-smokers (control group, n=38), Group 2 (n=39), - Tobacco heavy smokers, more than 10 cigarettes a day for at least 5 years, and Group 3 - Cannabis smokers (n=37) with at least 4 joints in a week for more than 3 years.
Chromatin integrity and DNA damage was assessed by using Chromomycine CMA₃ and Acridine Orange staining. The 8-OHG RNA assay was employed to measure oxidative damage. Besides, the whole genome of spermatozoa was extracted using a QIAamp DNA Mini Kit and the mitochondrial DNA was amplified by using the REPLI-g Mitochondrial DNA Kit. Polymerase chain reaction (PCR) was used to amplify the MT-CO1, MT-CO2 and MT-CO3 gene. Then, samples were purified and sequenced using the Sanger method.
The treatment of sperm cells with 10µL of THC, THC-COOH, and CBD resulted in a significant decline in total sperm motility upon exposure to THC and CBD (P ≤ 0.001 and P ≤ 0.003, respectively). Progressive motility was notably reduced (P ≤ 0.001), and the average number of immotile sperm significantly increased (P ≤ 0.003) following incubation with THC and CBD, respectively. However, only a slight reduction in total sperm motility was observed after incubation with THC-COOH.
In vivo, in the other hand, sperm count, and progressive motility showed no significant difference between the investigated groups (non-smokers, tobacco smokers, and cannabis smokers). However, the mean value of immotile spermatozoa and morphologically abnormal spermatozoa increased among smokers and cannabis smokers compared to non-smokers (58,92 % for Tobacco smokers, 68,66 % for cannabis smokers and 51,73 % for non-smokers). (5.02 for tobacco smokers, 2.26 for cannabis smokers and 7.46 for non-smokers). In addition, the mean value of chromatin condensation of spermatozoa showed a statistically significant difference among non-smokers (15 % ± 15.4), tobacco smokers (25.3 % ± 14.9; P ≤ .001), and cannabis smokers (37,13 % ± 20.1; P ≤ .001).
A cumulative sum of 22 single nucleotide polymorphisms (SNPs) was detected in the mitochondrial cytochrome c oxidase subunit 1 (Mt-Co1) gene, with a distribution of 37,8 %, 64,1 %, and 54 % among non-smoker, tobacco smoker, and cannabis smoker groups, respectively.
On the other hand, 17 Single Nucleotide Polymorphisms (SNPs) have been identified within the mitochondrial-encoded Cytochrome C Oxidase II (MT-CO2) gene, with a proportion of 21,62 %, 28,2 %, and 43,24 % among non-smoker, tobacco smoker, and cannabis smoker groups, respectively.
In the mitochondrial-encoded cytochrome c oxidase III gene (Mt-Co3), a total of 20 single nucleotide polymorphisms (SNPs) were identified, with a distribution of 54,05 %, 64,1 %, and 51,35 % among the investigated groups - non-smokers, tobacco smokers, and cannabis smokers, respectively. Nevertheless, none of these SNPs were significantly different between the three groups.
This study demonstrates that tobacco and cannabis smoking have a negative effect on sperm parameters, chromatin condensation (Sperm maturity) and DNA integrity of spermatozoa and should be avoided in men of reproductive age. It highlights the importance as well of promoting education and awareness regarding cannabis use and its extensive implications, affecting not only individual health but also the well-being of future generations.Jüngste umfassende Meta-Analysen haben eine bemerkenswerte Reduktion der Spermienkonzentration und der Gesamtspermienzahl bei Männern aus Nordamerika, Europa und Australien zwischen 1973 und 2011 aufgedeckt. Dieser Rückgang, der auf 50–60% geschätzt wird, betrifft Männer unabhängig von ihrem Fruchtbarkeitsstatus, ohne Anzeichen einer Stabilisierung in den letzten Jahren. Diese Ergebnisse deuten stark auf eine bedeutende Verschlechterung der männlichen reproduktiven Gesundheit hin, mit Auswirkungen, die über Fruchtbarkeitsbedenken hinausgehen (Levine H et al., 2017). Angesichts des Ausmaßes dieser globalen Verschiebung ist die überzeugendste Erklärung eine, die alle beteiligten Bevölkerungen universell betrifft. Es besteht kein Zweifel an den erheblichen Auswirkungen, die neue Lebensstiländerungen auf uns haben können. Es ist gut dokumentiert, dass das Rauchen von Tabak eine breite Palette physiologischer Funktionen negativ beeinflusst. Darüber hinaus stellt der Gebrauch von Tabak und Cannabis eine zunehmende Bedrohung für die männliche reproduktive Gesundheit dar. Obwohl die Prävalenz des Tabakrauchens im Laufe der Zeit bei Männern im fortpflanzungsfähigen Alter gesunken ist, hat der Gebrauch anderer eingeatmeter Produkte wie Cannabis zugenommen. Daher ist es entscheidend für das Wohlergehen zukünftiger Generationen, ihre potenziell schädlichen Auswirkungen auf die männliche Fruchtbarkeit zu verstehen. Zahlreiche Studien der letzten Jahrzehnte haben einen Zusammenhang zwischen dem Rauchen von Tabak oder Cannabis und einem Rückgang der Spermienqualität aufgezeigt, der potenziell zur männlichen Unfruchtbarkeit führt. Tabakrauchen, eine weltweit verbreitete Erscheinung, beeinträchtigt nicht nur das Wohlbefinden eines Einzelnen, sondern auch seine genetische Beschaffenheit erheblich. In den letzten Jahren haben umfangreiche Forschungen die komplexe Beziehung zwischen Tabakexposition und der Expression zahlreicher Gene untersucht. In jüngster Zeit hat sich der Cannabiskonsum nach der Legalisierung von Marihuana in verschiedenen Ländern und Bundesstaaten verändert, und es ist ein unerlässliches öffentliches Gesundheitsproblem aufgetreten, das sich nicht nur auf die Benutzer, sondern auch auf ihre Nachkommen auswirkt. Die Wahrnehmung der Cannabistoxizität und -sicherheit in Gesellschaft, Politik und sogar in wissenschaftlichen Kreisen hat sich in den letzten Jahrzehnten dramatisch verändert. Daraus ergeben sich einige Fragen zu den Auswirkungen von Marihuana (Cannabis sativa) auf die menschliche Physiologie und reproduktive Gesundheit auf kurze und lange Sicht. Das Ziel dieser Studie war es daher, die Auswirkungen von Tabak- und Cannabiskonsum auf die Spermienqualität, die Chromatinintegrität und den oxidativen Schaden bei Männern, die zuvor jährlich Tabak oder Cannabis konsumiert haben, zielt die Studie darauf ab, die Schäden zu untersuchen, die Tabak und Cannabis sowie ihre Bestandteile auf mitochondriale genetische Varianten der Spermien in den Cytochrom-C-Oxidase-1-, 2- und 3-Genen (MT-CO1, MT-CO2 und MT-CO3) verursachen. Speziell auf die Veränderungen im durch das Zytochromoxidase -kodierte Gen innerhalb der Spermienmitochondrien. Zunächst wurden 10 Samenproben einer in-vitro-Studie unterzogen, indem die Spermaparameter (Volumen, Spermienzahl, Beweglichkeit) innerhalb von 1 Stunde nach der Entnahme analysiert wurden, gemäß den WHO-Kriterien 2020. Zur Erzielung genauer Ergebnisse wurde ein computergestütztes Spermaanalyse (CASA) -System zur Bestimmung der Spermaparameter verwendet. Jede Probe wurde mit 1 mL; 10 μg/mL THC, THC-COOH und CBD in Methanol gelöst, belichtet. Alle Proben wurden auch mit 1 mL reinem Methanol als Kontrollgruppe belichtet, um die potenziellen Auswirkungen von Methanol auf Samenzellen zu eliminieren. Mehrere Abstriche (10 μL) jeder Probe wurden genommen, um die Funktionalität das Chromatin verdichten geschlechtsreifer Spermatozoen unter Verwendung von Chromomycin blaue (CMA3) und Desoxyribonukleinsäure Spaltung (Acridinorang) -Analysen zu bewerten. Anschließend wurden insgesamt 116 Proben von Männern unter 40 Jahren in Prince Rashid Bin Al Hassan Hospital (PRBH) in Irbid, Jordanien, gesammelt. Die Proben wurden in drei Gruppen unterteilt: Gruppe 1 - Nichtraucher (Kontrollgruppe, n = 38), Gruppe 2 (n = 39) - Tabak starke Raucher, mehr als 10 Zigaretten pro Tag für mindestens 5 Jahre, und Gruppe 3 - Cannabis Raucher (n = 37) mit mindestens 4 Joints pro Woche für mehr als 3 Jahre. Die Chromatin verdichten und der DNA schaden wurde durch Verwendung von Chromomycin CMA₃ und Acridin Orang-Färbung bewertet. Der 8-OHG-RNA-Test wurde verwendet, um den oxidativen Schaden zu messen. Darüber hinaus wurde das gesamte Genom der Spermatozoen unter Verwendung eines QIAamp-DNA-Mini-Kits extrahiert und die mitochondriale DNA unter Verwendung des REPLI-g mitochondrial DNA Kit amplifiziert. Die Polymerase-Kettenreaktion (PCR) wurde verwendet, um das MT-CO1-, MT-CO2- und MT-CO3-Gen zu amplifizieren. Anschließend wurden die Proben gereinigt und unter Verwendung der Sanger-Methode sequenziert. Die Behandlung von Samenzellen mit 10 μL THC, THC-COOH und CBD führte zu einem signifikanten Rückgang der Gesamtspermienmotilität nach der Exposition gegenüber THC und CBD (P ≤ 0,001 bzw. P ≤ 0,003). Die progressive Motilität wurde signifikant reduziert (P ≤ 0,001) und die durchschnittliche Anzahl von unbeweglichen Spermien stieg signifikant an (P ≤ 0,003) Anschließend zeigte sich nur eine leichte Reduktion der Gesamtspermienmotilität nach der Inkubation mit THC-COOH. In vivo hingegen zeigten die Samenanzahl und die progressive Motilität keinen signifikanten Unterschied zwischen den untersuchten Gruppen (Nichtraucher, Tabakraucher und Cannabisraucher). Der Mittelwert der unbeweglichen Spermatozoen und morphologisch abnormen Spermatozoen erhöhte sich jedoch bei Rauchern und Cannabisrauchern gegenüber Nichtrauchern (52,42% für Tabakraucher, 65,13% für Cannabisraucher und 44,59% für Nichtraucher). Bei den Rauchern für Tabak und Cannabisraucher betrug er entsprechend (5,02 bzw. 2,23 und 7,34). Außerdem zeigte der Mittelwert der Chromatinkondensation der Samenzoen unter den Nichtrauchern (14,68 ± 15,64), den Tabakrauchern (25,28 ± 14,86; P ≤ 0,024) und den Cannabisrauchern (34,83±18,39; P ≤ 0,001) einen statistisch signifikanten Unterschied.
Eine kumulative Summe von 22 einzelnen Nukleotidpolymorphismen (SNPs) wurde im mitochondriellen Zytochrom-c-Oxidase-Untereinheit 1 (Mt-Co1) -Gen gefunden, mit einer Verteilung von 37,8 %, 64,1 %, and 54 % bei Nichtrauchern, Tabakrauchern und Cannabisrauchern, respektive.
Auf der anderen Seite wurden 17 Einzel-Nukleotid-Polymorphismen (SNPs) im mitochondriell codierten Zytochrom-C-Oxidase-II (MT-CO2) -Gen identifiziert, mit einem Anteil von 21,62 %, 28,2 %, and 43,24 % bei Nichtrauchern, Tabakrauchern und Cannabisrauchern, respektive.
Im mitochondriell codierten Zytochrom-c-Oxidase-III-Gen (Mt-Co3) wurden insgesamt 20 einzelne Nukleotid-Polymorphismen (SNPs) identifiziert, mit einer Verteilung von 54,05 %, 64,1 %, and 51,35 % bei den untersuchten Gruppen - Nichtrauchern, Tabakrauchern und Cannabisrauchern, respektive. Dennoch gab es keine signifikanten Unterschiede zwischen den drei Gruppen in Bezug auf diese SNPs.
Diese Studie zeigt, dass Tabak- und Cannabisrauchen einen negativen Einfluss auf Spermienparameter, Chromatin-Kondensation (Spermienreife) und die DNA-Integrität von Spermatozoen haben und bei Männern im reproduktiven Alter vermieden werden sollten. Sie unterstreicht auch die Bedeutung der Förderung von Bildung und Bewusstsein in Bezug auf den Cannabiskonsum und seine umfangreichen Auswirkungen, die sich nicht nur auf die individuelle Gesundheit, sondern auch auf das Wohlergehen zukünftiger Generationen
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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