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Investigating the Use of Hair to Assess Polybrominated Diphenyl Ether (PBDE) Exposure Retrospectively, and in Male Infants with Genitourinary Tract MalformationsCarnevale, Amanda 11 July 2013 (has links)
Polybrominated diphenyl ethers (PBDEs) are synthetic chemicals that are added to a variety of consumer products as flame-retardants. The ubiquitous nature and endocrine disrupting properties of PBDEs are a public concern. A pilot study was performed to investigate whether in utero PBDE exposure, as measured in maternal hair, is associated with genitourinary tract malformations in male infants. In addition, we compared PBDE levels in maternal and infant hair and used segmental analysis to investigate how PBDEs varied along the shaft. Preliminary results suggest a trend toward an elevated PBDE body burden in mothers whose infants were born with genitourinary tract malformations; this was significant for some PBDEs. The sum of PBDEs (ΣPBDEs) in maternal hair did not correlate with infant hair levels; children had significantly greater levels. A significant increase in the ΣPBDEs was observed in distal hair suggesting hair PBDEs may be reflective of both internal and external exposure.
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Estructura i ultraestructura testicular del mascle reproductor porcí (Sus domesticus)Garcia Gil, Núria 18 December 2002 (has links)
El present treball analitza al microscopi òptic i al microscopi electrònic de transmissió el testicle de Sus domesticus (raça Landrace - varietat anglesa) a partir de mascles reproductors porcins adults i sans. L'objectiu principal de tots els centres d'Inseminació Artificial Porcina i de les Explotacions de Selecció i Multiplicació Porcina és garantir una excel·lent qualitat espermàtica al llarg de la vida reproductiva útil d'un mascle reproductor porcí. Així doncs, un millor coneixement dels patrons estructural i ultraestructural normals del testicle permetrà diagnosticar amb facilitat quina ha estat l'estructura o funció testicular afectada quan s'observa una disminució de la qualitat del semen. Les anàlisis seminals i hormonals són certament crucials en la valoració d'aquests mascles, però, no són totalment informatives de les alteracions testiculars, ja que és necessari conèixer l'organització microscòpica.Diversos estudis sobre testicle han demostrat que els marcadors més sensibles per a l'avaluació de la funció testicular són els següents: (1) la grandària testicular, (2) el gruix i l'organització de la càpsula testicular, (3) el percentatge de túbuls seminífers i de teixit intersticial en el parènquima testicular, (4) el diàmetre dels túbuls seminífers, (5) l'alçada i la composició de cèl·lules germinals de l'epiteli seminífer, (6) el gruix i l'organització de la làmina pròpia i, (7) la morfologia i la grandària de les cèl·lules de Leydig. El primer objectiu concret del present estudi ha estat, per tant, caracteritzar tots aquests paràmetres testiculars en mascles porcins sans i adults. L'organització estructural del testicle i les mesures quantitatives utilitzades com a marcadors no mostren diferències significatives ni entres els mascles porcins (P > 0,01), ni entre el testicle dret i l'esquerre (P > 0,01). Els testicles, de 330,80  16,99 g de pes, estan envoltats per una càpsula, de 2.375,13  246,68 m de gruix, la qual es divideix en tres capes: la túnica vaginalis constitueix l'1,82  0,78 % de la càpsula i està composta per una capa mesotelial externa i una capa interna de teixit conjuntiu dens; la túnica albuginea representa el 37,31  3,27 % i és de teixit conjuntiu dens i, la túnica vasculosa constitueix el 64,24 4,40 % i és de teixit conjuntiu lax. En el parènquima testicular els túbuls seminífers i el teixit intersticial representen el 72,44  2,12 % i el 27,46  2,12 %, respectivament. Els túbuls seminífers, de 226,23  18,08 m de diàmetre, es troben fortament recargolats i empaquetats, i estan compostos per la làmina pròpia i l'epiteli seminífer. La làmina pròpia, de 4-4,5 m de gruix, està formada per la làmina basal i dues capes de cèl·lules peritubulars. L'epiteli seminífer, amb una alçada mitjana de 66,11  10,62 m, és columnar i estratificat amb cèl·lules de Sertoli i diferents generacions d'espermatogònies, espermatòcits i espermàtides. El teixit intersticial és un teixit conjuntiu lax amb abundants cèl·lules de Leydig polièdriques fortament empaquetades (ca. 15 x 12 m).El segon objectiu concret d'aquest estudi ha estat estudiar des del punt de vista morfològic i morfomètric (alçada, longitud, freqüència relativa d'aparició i durada) els estadis del cicle de l'epiteli seminífer en els mascles porcins de la raça Landrace (varietat anglesa), classificats d'acord amb el mètode de la morfologia tubular. Els estadis premeiòtics ( I, II i III) ocupen el 31,9 % del cicle espermatogènic i es caracteritzen, principalment, per la presència de cèl·lules en les fase inicials de la meiosi I. Les primeres etapes de la meiosi I no afecten els paràmetres morfomètrics de l'epiteli seminífer ja que els valors obtinguts per l'alçada de l'epiteli seminífer, la freqüència relativa, la longitud i la durada d'aquests estadis són molt variables. Els estadis meiòtics (IV i V) representen el 16,4 % del cicle espermatogènic i estan constituïts, principlament, per cèl·lules en un estat avançat de la meiosi I i /o cèl·lules en meiosi II. Les últimes fases de la meiosi I i també de la meiosi II tenen lloc ràpidament, la qual cosa resulta en una baixa freqüència relativa d'aparició i, per tant, en una baixa durada dels estadis meiòtics. Els estadis postmeiòtics (VI, VII i VIII) ocupen el 50,6 % del cicle espermatogènic. L'esdeveniment més important que té lloc en aquests estadis és la fase de maduració de l'espermiogènesi. En la fase de maduració, les espermàtides experimenten diverses modificacions morfològiques i estructurals que donen lloc, finalment, als espermatozoides. La complexitat d'aquests processos fa que els estadis postmeiòtics presentin valors més grans de freqüència relativa, longitud i durada.El tercer objectiu concret d'aquest treball ha estat descriure a nivell ultraestructural el procés d'espermiogènesi, i relacionar les transformacions que experimenten les espermàtides en fase d'elongació amb els canvis ultraestructurals que tenen lloc en les diferents cèl·lules que constitueixen el testicle (cèl·lules germinals, de Sertoli i de Leydig, principalment). L'espermiogènesi del mascle porcí de la raça Landrace (varietat anglesa) s'ha dividit en 9 passos que vénen definits per 9 tipus diferents d'espermàtides. Al llarg de l'espermiogènesi no s'observen diferències ultraestructurals significatives (P > 0,01) ni entre els mascles porcins ni entre el testicle esquerre i dret en les cèl·lules que constitueixen el testicle. / The present study describes the structure and ultrastructure of the Sus domesticus testis (Landrace breed -british variety) from healthy adults boars. The main goal of the whole of Porcine Artifitial Insemination Centres and of the Porcine Livestocks is to guarantee an excellent spermatic quality along the boar reproductive life. Therefore, a better knowlegment of the normal structural and ultrastructural patterns of the testis will improve the prognosis of subfertility when a low spermatic quality is observed. Both seminal and hormonal analysis are certainly crucial in the assessment of these males, but it is also necessary to know the microscopic organization.Several studies have demonstrated that the most sensitive markers of impaired function are: (1) the testicular size, (2) the thickness and organization of the testicular capsule, (3) the percentage of seminiferous tubules and interstitial tissue in the testicular parenchyma, (4) the diameter of seminiferous tubules, (5) the height and germ cell composition of the seminiferous epithelium, (6) the thickness and organization of the lamina propria, and (7) the Leydig cell size and morphology. The first aim of this study has been to characterize all these testicular parameters in healthy adults boars. The structural organization of the testis and quantitative measures used as markers did not differ significantly either among boars (P > 0.01), or between left and right testes (P > 0.01). Testes, of 330.80  16.99 g weight, were surrounded by a capsule, of 2,375.13  246.68 m thick, divided into three layers: the tunica vaginalis constituted 1.82  0.78% of the capsule and was composed by an outer mesothelial layer and an inner dense connective tissue layer; the tunica albuginea represented 37.31  3.27% and was of dense connective tissue and the tunica vasculosa constituted 64.26  4.40% and was of loose connective tissue. In the testicular parenchyma, the seminiferous tubules and the interstitial tissue comprised 72.44  2.12% and 27.46  2.12%, respectively. Seminiferous tubules were highly convoluted ducts of 226.23  18.08 m in diameter composed by a lamina propria and the seminiferous epithelium. The lamina propria, of 4-4.5 m thick, was formed by basal lamina and two layers of peritubular cells. The seminiferous epithelium, of 66.11  10.62 m high, was stratified columnar with Sertoli cells and different generations of spermatogonia, spermatocytes and spermatids. The interstitial tissue was loose connective tissue with abundant and closely-packed polyhedral Leydig cells (av. 15 x 12 m).The second aim of this study has been to describe the morphological features of the eight stages of the seminiferous epithelium in Landrace boars (british variety) according to the tubular morphology method, as well as their relative frequency, length, height and duration. Premeiotic stages (I, II and III) occupied the 31.9 % of the spermatogenic cycle and were mainly characterized by the presence of cells in the initial phases of meiosis I. Early meiosis I did not affect the morphometric parameters of the seminiferous epithelium as indicated by the variable values obtained in the seminiferous epithelium height, as well as in the relative frequency, length, and duration of premeiotic stages. Meiotic stages (IV and V) represented the 16.4 % of the spermatogenic cycle and were constituted, mainly, by cells in advanced meiosis I and/or cells in meiosis II. Last phases of meiosis I and also meiosis II occurred rapidly, resulting in low relative frequency and, therefore, in low duration of meiotic stages. Postmeiotic stages (VI, VII and VIII) occupied the 50.6 % of the spermatogenic cycle. The most important event of these stages was the maturation phase of spermiogenesis. The maturation phase included several morphological and ultrastructural modifications in spermatids, resulting in the formation of spermatozoa. The complexity of these processes correlated with the high relative frequency, length, and duration of postmeiotic stages.The third aim of this study has been to describe the spermiogenesis process at ultrastructural level and, to relate the spermatid transformations along the spermiogernesis with the ultraestructural changes undergoing in testicular cells (mainly germinal, Sertoli and Leydig cells).The spermiogenesis of Landrace boars (british variety) was divided into 9 steps, each one characterized by the presence of an specific spermatid type. Significant differences were found neither among the three healthy boars (P > 0.01), nor the left and right testes (P > 0.01) in the ultrastructure of the testiculars cells along spermiogenesis.
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Efeitos de diferentes tipos de treinamento físico nos parâmetros reprodutivos de ratos Wistar superalimentados na infânciaBolotari, Mariana 09 March 2018 (has links)
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Previous issue date: 2018-03-09 / A obesidade pode ter sua origem durante fases críticas de
desenvolvimento, como o período de lactação, através da programação
metabólica. Em modelos experimentais, a sobrenutrição na infância é estudada
pelo método de redução de ninhada. Sendo a obesidade/sobrepeso condições
importantes para o desenvolvimento de desordens metabólicas e reprodutivas,
o nosso objetivo foi de avaliar os efeitos de duas modalidades de exercício físico
em esteira (endurance e H.I.I.T) realizados em períodos de plasticidade
metabólica nos parâmetros reprodutivos e metabólicos de indivíduos
programados metabolicamente na infância pela superalimentação. Ratos
machos Wistar foram divididos em dois grupos, um com o tamanho de ninhada
padrão, com 10 machos por ninhada, que não foi submetido ao treinamento físico
(NCSed) e outro com o tamanho da ninhada reduzida para quatro
machos/ninhada, esses animais após o desmame foram subdivididos em três
grupos: grupo sedentário (NRSed), grupo exercitado endurance (NREnd) e
grupo exercitado H.I.I.T (NRHiit). Foram realizados testes metabólicos como o
teste oral de tolerância à glicose, teste de tolerância à insulina, o perfil bioquímico
desses animais também foi avaliado, assim como o peso, consumo, peso das
gorduras retroperitonial e perigonadal e dos órgãos dos componentes do sistema
reprodutor masculino. A vitalidade, concentração, morfologia espermática e a
organização estrutural do epidídimo e dos testículos também foram analisadas.
O modelo de superalimentação por redução de ninhada foi eficaz para indução
da obesidade, não alterando os parâmetros espermáticos nem a organização
estrutural dos órgãos reprodutivos avaliados. Os grupos exercitados (NREnd e
NRHiit) apresentaram menor gordura retroperitonial, perigonadal, glicemia, e
uma melhora na resistência à insulina e no teste de capacidade física, quando
comparados com NCSed. Assim, sugerimos que a superalimentação na infância,
induzida por redução de ninhada, não afeta a capacidade reprodutiva e que o
exercício físico foi capaz de alterar alguns parâmetros, como o peso das
gorduras e o metabolismo glicêmico, associados à síndrome metabólica
observados nos animais adultos obesos neste modelo de programação. / Obesity may have its origin during critical stages of development, such as
the lactation period, through metabolic programming. In experimental models,
overfeeding in childhood is studied by the litter reduction method. Obesity/
overweight were important conditions for the development of metabolic and
reproductive disorders, our objective was to evaluate the effects of two physical
exercise modalities (endurance and HIIT) performed in periods of metabolic
plasticity in the reproductive and metabolic parameters of individuals
programmed in childhood by overfeeding. Male Wistar rats were divided into two
groups, one with standard litter size, with 10 males per litter, which was not
submitted to physical training (NCSed) and the other with litter size reduced to
four males / litters; were divided into three groups: sedentary group (NRSed),
endurance exercised group (NREnd) and exercised group HIIT (NRHiit).
Metabolic tests such as the oral glucose tolerance test, insulin tolerance test, the
biochemical profile of these animals were also evaluated, as well as the weight,
consumption, weight of retroperitoneal and perigonadal fats and organs of the
components of the male reproductive system . Vitality, concentration, sperm
morphology and structural organization of the epididymis and testis were also
analyzed. The model of overfeeding by litter reduction was effective for obesity
induction, without altering the sperm parameters nor the structural organization
of the reproductive organs evaluated. The exercised groups (NREnd and NRHiit)
presented lower retroperitoneal, perigonadal, glycemia, and an improvement in
insulin resistance and physical capacity test when compared with NCSed. Thus,
we suggest that overfeeding in childhood induced by litter reduction does not
affect reproductive capacity and that physical exercise was able to change some
parameters, such as fat weight and glycemic metabolism, associated with the
metabolic syndrome observed in adult animals obese in this programming model.
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Investigating the effects of nicotine on the male reproductive systemMaartens, Pieter Johann 12 1900 (has links)
Thesis (MScMedSc)-- Stellenbosch University, 2013. / ENGLISH ABSTRACT: Much has been documented about the detrimental effects of adverse lifestyle factor
exposure on the body. Exposure to factors, such as cigarette smoke, have proved to not
only be a burden on global health and economy, but have also led to growing concerns
about effects on systemic functions such as reproduction. The aim of the present study was
to determine the effects of in utero and in vitro nicotine exposure on spermatozoal function
and the antioxidant enzyme activity and lipid peroxidation (LPO) status of the male
reproductive system. A better understanding of this process is necessary to combat the
respective burdens of smoking and male infertility and for the prospective development of
treatment strategies.
Two experimental models were employed: Wistar rats were exposed to nicotine in utero
while human and rat spermatozoa were exposed to nicotine in vitro. In utero studies were
achieved by selecting healthy pregnant rats and treating them with 1 mg/kg-bodyweight/day
nicotine or 1 ml/kg-bodyweight/day 0.85% physiologic saline throughout gestation and
lactation. Male rat pups were selected and sacrificed at each of the following age groups
(n=6): 42 days, 84 days and 168 days old. The pups were only exposed to the
treatment/saline via placental uptake or lactation. Biochemical analyses of the tissue
comprised of measurement of LPO and antioxidant enzyme activity. Results indicated a
significant association of maternal nicotine exposure to decreased levels of primary
antioxidant enzymes in rat testes. Of particular note was the observation that the treatment
group, of which each of the respective antioxidant enzyme levels were significantly less than
the control group, was the oldest (d168) rat group.
In vitro studies were achieved by collecting sperm samples from healthy human donors
(n=12), healthy rats (n=6) and obese rats (n=6). Samples were washed and exposed to
different concentrations of high levels of nicotine (Control, 0.1mM, 1mM, 5mM, 10mM) in
vitro. Semen parameters such as motility, viability and acrosome reaction were monitored at
different time points (30min, 60min, 120min, 180min). Results revealed increasing in vitro nicotine concentrations were associated with decreased viability and acrosomal status of
human spermatozoa and decreased progressive motility and viability of rat spermatozoa.
Obesity was also associated with decreases in progressive motility and viability of rat
spermatozoa.
These results indicate that the acute in vitro exposure of spermatozoa to high levels of
nicotine could adversely affect semen quality and may be an additive factor to the
impediment of male fertility. In utero results reveal maternal nicotine exposure adversely
affects male fertility in later life and seems to elicit more detrimental effects on the
reproductive system than that of direct nicotine exposure to spermatozoa. Obesity also
inhibits parameters of male fertility and these effects are exacerbated by nicotine exposure.
The authors believe these adverse effects on the reproductive system to be related to an
increased activation of leukocytes, excess production in reactive oxygen species (ROS) and
consequent onset of oxidative stress (OS). Nevertheless this study agrees with other studies
that nicotine exposure may be an additive factor to the impediment of male fertility. / AFRIKAANSE OPSOMMING: Daar is reeds baie bekend oor die moontlik newe effekte vir die liggaam wat met ‘n
ongesonde lewenstyl gepaard gaan. Menslike blootstelling aan sulke faktore, soos sigaret
rook, is wêreldwyd ‘n las vir gesondheid en ekonomie en het gelei tot geweldige kommer
onder navorsers oor die moontlike komplikasies vir liggaamlike funksies soos voortplanting.
Die doel van die betrokke projek was om die effekte van in utero en in vivo nikotien
blootstelling op die antioksiderende ensiem aktiwiteit en lipied peroksidasie status van
reproduktiewe weefsel en die funksionele parameters van spermatozoa te bepaal. ‘n Beter
begrip van hierdie proses is noodsaaklik om die las van rook en vetsug teen te werk en vir
die moontlike ontwikkeling van behandelingsstrategieë.
Twee eksperimentele modelle is ontwerp: Wistar rotte is in utero blootgestel aan nikotien
terwyl mens- en rot- spermatosoë ook in vitro aan nikotien blootgestel is. Vir die in utero
studie is gesonde dragtige rotte gedurende swangerskap en laktasie met 1 mg/kgliggaamsgewig/
dag nikotien of 1 ml/kg-liggaamsgewig/dag 0.85% fisiologiese soutoplossing
behandel. Manlike welpies is gekies en geoffer op elk van die volgende ouderdomme (n=6):
42 dae, 84 dae en 168 dae. Die welpies is slegs aan nikotien blootgestel deur plasentale
opname en laktasie. Biochemiese analise van die testikulêre weefsel het ‘n beduidende
assosiasie getoon tussen maternale nikotien blootstelling en verminderde vlakke van die
primêre antioksiderende ensieme. Die 168 dag oue groep het ‘n merkbare vermindering
getoon tussen kontrole en nikotien weefsel vir elk van die antioksiderende ensieme.
Vir die in vitro studie is sperm monsters verkry vanaf gesonde mans (n=12), gesonde rotte
(n=6) en vet rotte (n=6). Monsters is gewas en in vitro blootgestel aan verskeie hoë vlakke
van nikotien (kontrole, 0.1mM, 1mM, 5mM, 10mM). Seminale parameters soos motiliteit,
lewensvatbaarheid en akrosoom status is by verskei tydpunte gemeet (30min, 60min,
120min, 180min). Dit blyk dat verhoging in in vitro nikotien konsentrasies verband hou met
verlaagde lewensvatbaarheid en akrosoom status van menslike spermatosoë en verlaagde
progressiewe motilteit en lewensvatbaarheid van rot spermatosoë. Vetsug is ook geassosieer met verlagings in progressiewe beweeglikheid en lewensvatbaarheid van rot
spermatosoë.
In utero resultate openbaar dat maternale nikotien blootstelling manlike vrugbaarheid nadelig
beïnvloed in latere lewe en blyk dat dit meer van ‘n nadelige uitwerking op die
voortplantingstelsel het as dié van direkte nikotien blootstelling aan spermatosoë. In vitro
blootstelling van spermatosoë aan hoë vlakke van nikotien, het wel ook semen kwaliteit
nadelig beïnvloed. Vetsug inhibeer ook manlike vrugbaarheids parameters en hierdie effek
word vererger deur nikotien blootstelling.
Die outeure glo dat hierdie nadelige uitwerking op die voortplantingstelsel verband hou met
'n verhoogde aktivering van leukosiete, oortollige produksie van reaktiewe suurstof spesies
en die gevolglike aanvang van oksidatiewe stres bevorder. Hierdie studie stem wel ooreen
met ander studies wat nikotien blootstelling bestempel as ‘n bydraende faktor tot die
struikelblok van manlike onvrugbaarheid. / Harry Crossley Foundation (South Africa)
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Cultiu de les cèl·lules epididimàries de "Sus domesticus": anàlisi estructural, funcional i proteòmicBassols Casadevall, Judit 21 June 2006 (has links)
En aquest treball s'han desenvolupat dos mètodes simples i ràpids pel cultiu de les cèl·lules epitelials de les tres regions de l'epidídim de Sus domesticus. Un es basa en el cultiu de fragments del túbul epididimari intactes durant 8 dies. L'altre mètode es basa en el cultiu de fragments del túbul epididimari digerits amb col·lagenasa que, després de 7 dies, donen lloc a la formació d'una monocapa de cèl·lules epitelials epididimàries que adquireixen el 90-100% de confluència després de 12-16 dies en cultiu. Aquestes cèl·lules es mantenen viables durant més de 60 dies en cultiu i no s'observa proliferació de cèl·lules no epitelials. Per determinar el nivell de conservació de les característiques epididimàries en els cultius s'ha analitzat l'estructura cel·lular, l'activitat de síntesi i secreció proteica, i el manteniment i maduració dels espermatozoides en cocultiu. / In this work, we have developed two simple and quick methods for the culture of boar epididymal epithelial cells. The first one involves the culture of intact epididymal tubule fragments during 8 days. The second one involves the culture of epididymal tubule fragments digested with collagenase that, after 7 days in culture, allows the formation of an epididymal epithelial cell monolayer that reached 90-100% confluence after 12-16 days. These epididymal epithelial cells monolayers were maintained in vitro for more than 60 days and overgrowth of non-epithelial cells was not observed. To estimate the level of preservation of epididymal characteristics in these cultures we have focused on cell morphology, protein secretion activity, and sperm preservation and maturation.
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The Effects of Testicular Nerve Transection and Epididymal White Adipose Tissue Lipectomy on Spermatogenesis in Syrian HamsterSpence, Jeremiah E 30 July 2008 (has links)
Previous investigators demonstrated that epididymal white adipose tissue (EWAT) lipectomy suppressed spermatogenesis and caused atrophy of the seminiferous tubules. EWAT lipectomy, however, may disrupt testicular innervation, which reportedly compromises testicular function. To resolve this confound and better clarify the role of EWAT in spermatogenesis, three experimental groups of hamsters were created in which: i.) the superior and inferior spermatic nerves were transected (SSNx) at the testicular level, ii.) EWAT was extirpated (EWATx), and iii.) testicular nerves and EWAT were left intact (SHAM controls). It was hypothesized that transection of the superior and inferior spermatic nerves would disrupt normal spermatogenesis. The findings indicate a significant reduction in spermatogenic activity and marked seminal tubule atrophy within the EWATx testis, as compared to the SSNx and controls testes, which did not differ significantly from each other. From these data, it is concluded that EWAT, and not testicular innervation, is central to normal spermatogenesis.
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Efectes del fotoperíode sobre la qualitat espermàtica de mascles porcins Sus domesticusSancho Badell, Sílvia 18 December 2002 (has links)
En el presente estudio se analizan los efectos de los fotoperiodos ambientales de otoño e invierno y los fotoperiodos experimentales de 24, 12 y 0 horas de luz artificial sobre la calidad del semen de machos reproductores porcinos de raza Landrace.El estudio se realizó sobre 30 machos postpuberales de 8 meses de edad y testados con el fin de comprobar la homogeneidad. Los machos fueron distribuidos aleatóriamente en los 3 grupos de luz artificial durante 3 meses. El tratamiento de 12 horas de luz artificial fue considerado como grupo control. Previamente al inicio de cada tratamiento, se sometió a cada grupo de machos al fotoperiodo ambiental correspondiente a la época del año; así, se caracterizó también la calidad seminal en otoño e invierno, manteniendo la temperatura constante.La nave experimental que acogió a los machos tiene una superficie de 100 m2 y una altura de 3,5 m. Un pasillo central divide la nave en dos hileras de 5 y 6 celdas respectivamente. En una de las celdas pequeñas se instaló el maniquí y fue utilizada para las extracciones de semen. La iluminación artificial se consiguió con la instalación de 6 lámparas fluorescentes en el techo del pasillo central que proporcionaron una luz homogénea superior a 200 lux. Así mismo, la nave se mantuvo en todo momento a 21±1ºC y la humedad relativa osciló entre el 60-75%.A todos los verracos se les proporcionó una dieta nutritiva y equilibrada y se les sometió a un regimen de extracciones de semen de 2 veces por semana, habiendo sido previamente entrenados en la monta del maniquí.Les muestras de semen fueron recogidas según la técnica de la mano enguantada (Martín, 1982; Daza, 1992) y se analizaron los siguientes parámetros: el volumen y el pH seminales, la concentración, la vitalidad y la motilidad espermáticas, la resistencia acrosómica de los espermatozoides, la morfología espermàtica a partir de la frecuencia de los espermatozoides maduros, inmaduros y aberrantes, la producción testicular y el número de dosis seminales. Se analizó, además, bioquímicamente el plasma seminal al principio y al final de cada tratamiento experimental de luz artificial a partir de la concentración de proteína total, de la identificación de residuos fosforilados de proteína y del contenido de azúcares. También se determinaron los índices de fertilidad y prolificidad. El volumen y el pH de los eyaculados se utilizaron como marcadores del estado funcional de las glándulas sexuales accesorias; la concentración espermàtica como un indicador de la actividad testicular (Pinart y col., 1999). La vitalidad y la motilidad espermáticas fueron estimadores del grado de diferenciación del espermatozoide tanto a nivel testicular como epididimario; la resistencia acrosómica fue utilizada para valorar el nivel de diferenciación de la membrana acrosómica durante la espermiogénesis y/o maduración epididimària (Briz i col., 1996; Pinart i col., 1999). Referente a la morfología espermática, los espermatozoides inmaduros fueron marcadores de anomalías en la maduración de éstos a lo largo del conducto epididimario y los espermatozoides aberrantes se utilizaron como marcadores de una diferenciación defectuosa a nivel de testículo (anomalías primarias) y a nivel de conducto epididimario (anomalías secundarias) (Briz i col., 1996). La concentración de proteína total se utilizó para valorar la integridad funcional de las membranas del espermatozoide y la actividad de las glándulas sexuales accesorias. La identificación de proteínas con residuos de tirosina fosforilados fue un estimador de la viabilidad celular y la actividad de las glándulas sexuales, y el contenido de azúcares como un indicador de la producción de las vesículas seminales.La determinación del volumen y el pH de los eyaculados se realizó en las instalaciones de la granja a partir de semen fresco el mismo día de la extracción. El resto de parámetros se analizaron en el laboratorio durante las 48 horas posteriores a la extracción a partir de semen diluido en BTS (diluyente de Bestville) (Daza, 1992) y transportado y conservado a 15ºC. Las muestras fueron previamente filtradas con el fin de eliminar la tapioca.El estudio estadístico de los resultados obtenidos se realizó a partir del análisis de la varianza (ANOVA) con un nivel de significación de =0,05.En cuanto al estudio comparativo de los fotoperiodos ambientales estacionales se ha observado un incremento significativo del pH del eyaculado en los machos expuestos a otoño (P0,0001), mientras que el volumen seminal se mantiene en valores similares en ambos tratamientos (P=0,1650). La concentración espermàtica, la producción espermàtica y el número de dosis seminales que se pueden preparar a partir de un eyaculado se duplica en los verracos sometidos al fotoperiodo de primavera (P0,0001). La vitalidad y la motilidad espermáticas no experimentan cambios significativos entre tratamientos (P=0,3440 y P=0,9220, respectivamente). La resistencia osmótica de los acrosomas desciende únicamente en los machos expuestos a condiciones estacionales de otoño (P0,0001). En referencia a la morfología espermàtica aunque no se observan diferencias entre primavera y otoño (P0,05), sí se detecta un incremento de los porcentajes de espermatozoides inmaduros y aberrantes en ambos fotoperiodos estacionales, y en especial en los machos expuestos a condiciones fotoperiódicas de otoño. Según los resultados obtenidos en este estudio la calidad seminal de los verracos es inferior en el fotoperiodo de otoño debido a un descenso de la concentración y la producción espermáticas, un aumento del pH seminal, una disminución de la resistencia de la membrana acrosómica y a un incremento en la frecuencia de espermatozoides inmaduros y aberrantes. Parece ser, pues, que en el otoño tiene lugar la disminución de la producción testicular, cambios en la actividad de las glándulas sexuales accesorias y disfunciones en el proceso de diferenciación testicular y epididimària de los espermatozoides y especialmente del acrosoma.En relación a los resultados obtenidos en el estudio de los diferentes fotoperiodos artificiales se observa que la iluminación continua provoca un aumento significativo del volumen del eyaculado en el primer y segundo mes de tratamiento (P0,0001), disminuyendo en el tercer mes. La oscuridad absoluta no modifica este parámetro (P0,05). En cuanto al pH seminal la iluminación continua provoca un incremento progresivo del valor del pH a lo largo del periodo experimental (P0,0001), mientras que la oscuridad absoluta tiene un efecto más irregular. La exposición de los machos a iluminación continua y a oscuridad absoluta se manifiesta en un descenso de la concentración y la producción espermáticas que se mantiene hasta el segundo mes de tratamiento (P0,0001), observándose un incremento en el tercer mes de exposición de los machos a oscuridad absoluta (P=0,1010). De todas maneras, este descenso es mas severo en los machos sometidos a iluminación continua ya que no presentan recuperación. La vitalidad y la motilidad espermáticas no se ven alteradas por la iluminación continua y la oscuridad absoluta, ni tampoco el contenido de los azúcares mayoritarios del plasma seminal (P0,005). La glucosa aparece como un azúcar minoritario y sí que presenta concentraciones inferiores en los tratamientos experimentales de luz continua y de oscuridad absoluta (P0,0001 y P=0,0002, respectivamente). La resistencia osmótica de los acrosomas desciende en ambos tratamientos artificiales extremos de luz continua y oscuridad total (P0,0001), aunque en los machos expuestos a iluminación continua se produce una recuperación a partir del segundo mes de tratamiento (P=0,4930). Dado que tampoco se han observado diferencias significativas en las concentraciones de proteína total (P0,05), es probable que las anomalías de la membrana acrosómica se originen durante el proceso de espermiogénesis y/o maduración epididimària. La exposición de los verracos a oscuridad absoluta no altera la morfología espermàtica de los eyaculados, aunque se observa un aumento de la frecuencia de espermatozoides con anomalías en la forma de la cola en el primer mes (P0,0001), y un aumento de la frecuencia de espermatozoides inmaduros con gota distal y de espermatozoides con anomalías en el número de colas en el tercer mes de experimentación (P=0,0030 y P0,0001). La luz continua, sin embargo, provoca un incremento de la frecuencia de espermatozoides inmaduros con gota distal (P0,0001) y de espermatozoides con anomalías en la forma de la cola (P=0,0040) ya en el primer mes. El fotoperiodo provoca un descenso de la fertilidad de los machos expuestos a oscuridad absoluta en el tercer mes de tratamiento (P0,0001) y un incremento de ésta en los machos sometidos a iluminación continua (P=0,0005). La prolificidad no se ve modificada por ambas condiciones extremas de luz artificial (P0,05). Así pues, los resultados obtenidos demuestran que el fotoperiodo afecta la actividad testicular, provoca alteraciones en la actividad de las glándulas sexuales accesorias, altera el proceso de expulsión de la gota citoplasmática y provoca anomalías en el proceso de diferenciación de la cola tanto a nivel testicular como epididimario, siendo los verracos expuestos a luz continua más sensibles a estos parámetros que los verracos sometidos a oscuridad absoluta. El fotoperiodo, sin embargo, no altera de forma esencial la integridad de las membranas del espermatozoide ni la capacidad fecundante de éste. / The present study analizes the effects of ambiental photoperiods of srping and autumn and of experimental photoperiods of 24, 12 and 0 hours lighting on the semen quality of Landrace boars.For this purpouse 30 healthy postpuberal boars of 8 months of age were selected; the males chosed showed both facility to mount on the dummy and high semen quality. In order to determine the effects of light on seminal features. Boars were randomly distributed into 3 experimental groups throughout 3 months. The artificial photoperiod of 12 h was considered a control treatment. Previous to the initiation of each experimental treatment, the males were exposed in a natural photoperiod of autumn or spring for 15 days by maintaining the temperature constant.In all groups the boars were kept in a experimental room of 100 m2 and 3,5 m high, divided into 2 files of 5 and 6 boxs, respectively. One box contained the dummy and was reserved for semen collections. The artificial lighting, upper the 200 lux, was obtained from 6 regulaly distributed lamps in the ceiling. The experimental room was always maintained in a temperature of 201ºC and an humidity of 60-75%.Boars were fed with a nutritious diet, and subjected to a semen collection rythm of twice per week. Semen samples were obtained by the gloved hand method. For each semen sample the parameters analized were the ejaculate volume and pH, the sperm concentration, vitality and motility, the acrosomic resistance, the sperm morphology from the frequency of mature, immature, and aberrant spermatozoa, the testicular production and the number of dosis for each ejaculate. Moreover, samples from the day 30th and 90th of each experimental treatment were processed for biochemical analysis in order to determine protein concentracion and identificate the tyrosine phosphorilated residues and to determine fructose, sorbitol and glucose concentrations; and, also they were processed to value fertility and prolificity indexs.The volume and pH of the ejaculates were measured from the sperm fraction the same day of the extractions. The other seminal parameters were analized in the 48 hours after the obtention of the samples from the filtration and dilution of the sperm fraccion. Statistical comparisons were made using the analysis of variance ANOVA at a significance level of =0,05.The comparative study of natural photoperiods indicated that pH was significantly higher in males under autumn conditions, while seminal volume did not differ. Sperm concentration, sperm production and number of seminal dosis were higher in males exposed to spring conditions. Sperm vitality and sperm motility was similar in males exposed to both spring and autumn conditions, whereas osmotic resistance of acrosomes was lower in autumn photoperiod. The sperm morphology did not differed between treatments, but in males exposed to autumn photoperiod an increase of the frequency of inmature and aberrant spermatozoa was found.These results show that the sperm quality of boars was lower in autumn photoperiod than in spring photoperiod due to low sperm concentration and sperm production, a high pH value of semen, a low osmotic resistance of acrosome and a high frequency of inmature and aberrant spermatozoa. Thus, autumn conditions induces a decrease in testicular production, and dysfunctions in both testicular and epididymal differentiation of spermatozoaThe comparative study of artificial photoperiods showed that 24 h lighting resulted in an increase of seminal volume in the first and second months of treatment, whereas 0 h lighting did not affect this parameter. The pH of semen increased progressively throughout the 24h treatment, whereas the 0h treatment showed an irregular effect on this parameter. Both experimental conditions produced a decrease in sperm concentration and sperm production until the second month; this decrease was more severe in males exposed to 24 h lighting. Neither the sperm vitality and motility nor the fructose and sorbitol concentration were affected by experimental condictions. In our study, glucose appeared as a minoritary sugar that was affected by artificial photoperiod. The effect of artificial photperiod on osmotic resistance of acrosome was more severe in darkness than in continuous lighting. The exposure of boars to darkness and continuous lighting did not alter the sperm morphology; however an increase of the frequency of inmature spermatozoa with distal droplet and aberrant spermatozoa with tail anomalies. The total protein concentration and the content of phophorilated tyrosine residues showed normal values throughout the experimental treatments. Fertility and prolificity were not affected by experimental conditions; however in males exposed to darkness a decrease in fertility was found in the third month of threatment.Data obtained indicate that photoperiod affects the semen quality of boars by decreasing the sperm concentration and sperm production, the osmotic resistance of acrosome and the glucose concentration, and by increasing the frequencies of inmature and tail aberrant spermatozoa; these alterations were more severe in those males exposed to 24h lighting thant in males exposed to 0h lighting. However, despite these anomalies both the fecundity and prolificity are not disturbed. Lack of abnormalitites in fecundity and fertility are correlated with the normal content of both sugar and proteins in seminal plasma of boars.
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The effects of the wild african potato (hypoxis hemerocallidea) supplementation on streptozotocin-induced diabetic wistar rats reproductive functionJordaan, Audrey Emmerentia January 2015 (has links)
Thesis (MTech (Biomedical Technology))--Cape Peninsula University of Technology, 2015. / Diabetes mellitus (DM) has been reported to be one of the greatest global public health threats. Statistics of the fertility status of modern society has linked increased DM to a decrease in fertility rates. Hyperglycaemia is characteristic of DM that results in a disturbance of proteins, lipids and carbohydrate metabolism leading to an increase production of reactive oxygen species (ROS). In the case where ROS overwhelms antioxidant mechanisms, the body goes into state of oxidative stress (OS). OS plays a vital role in the progression of DM which leads to dysfunction and damage of various organs including that of the reproductive system. Os has shown to cause damage to the sperm membraneby oxidation of polyunsaturated fatty acids (PUFA’s) as the sperm membrane are rich in PUFA’s. This damage contributes to reduced sperm motility, concentration, morphological abnormalities and the sperms ability to fuse with the ZP of the oocyte. DM has been observed to cause testicular degeneration by interrupting sertoli cell production and maintenance thus resulting in a disturbance of the normal functioning of the reproductive system. Experimental studies have targeted more natural sources for treating DM and its complications of the reproductive system. Plants and natural dietary substances have shown to have high antioxidant contents that combat DM induced oxidative stress. This study explored the effect the Hypoxis hemerocallidea (H. hemerocallidea) supplementation on testicular and epididymal tissue, sperm motility and reproductive hormones in male wistar rats. The experiment were conducted for 6 weeks and the rats (230-260 grams) were randomly divided into 5 groups (n=12 per group). Diabetes was induced in 3 of the 5 groups. The first group was the normal control group (A), second the diabetic control group (B), third was the diabetic group treated with 800mg/kg H. hemerocallidea (group C), fourth the diabetic group treated with 200mg/kg H. hemerocallidea (group D) and fifth the non-diabetic group supplemented with 800mg/kg H. hemerocallidea (group E). Blood glucose showed a significant increase in the diabetic group when compared to the normal control and treated groups. H. hemerocallidea showed improvement in sperm motility and sperm morphology more at 800mg/kg when compared to diabetic group and diabetic group treated with 200mg/kg. Body, testicular and epipidymal weights of diabetic control were significantly lower when compared to the other groups. Testicular and epididymal Malondialdehyde levels were decreased in normal control, diabetic groups treated with different doses of H. hemerocallidea and the non-diabetic group supplemented with H. hemerocallideaon comparing with the diabetic control group. Antioxidants such as Superoxide dismutase, Catalase and total Glutathione activity was observed to be dosage dependent in certin groups but most showed a significant increase when compared to the diabetic control group. The total antioxidant capacity was measured using Oxygen radical absorbance capacity (ORAC) and Ferric ion reducing antioxidant power (FRAP); increase was observed when normal control group and treated groups were compared to the diabetic group. Testosterone and estradiol levels were also increased when the normal control group and treated groups were compared to the diabetic control group.
Based on our findings it can be concluded that H. hemerocallidea supplementation can potentially be used to counteract deleterious effects of DM on the male reproductive system.
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The Effects of Testicular Nerve Transection and Epididymal White Adipose Tissue Lipectomy on Spermatogenesis in Syrian HamsterSpence, Jeremiah E. 30 July 2008 (has links)
Previous investigators demonstrated that epididymal white adipose tissue (EWAT) lipectomy suppressed spermatogenesis and caused atrophy of the seminiferous tubules. EWAT lipectomy, however, may disrupt testicular innervation, which reportedly compromises testicular function. To resolve this confound and better clarify the role of EWAT in spermatogenesis, three experimental groups of hamsters were created in which: i.) the superior and inferior spermatic nerves were transected (SSNx) at the testicular level, ii.) EWAT was extirpated (EWATx), and iii.) testicular nerves and EWAT were left intact (SHAM controls). It was hypothesized that transection of the superior and inferior spermatic nerves would disrupt normal spermatogenesis. The findings indicate a significant reduction in spermatogenic activity and marked seminal tubule atrophy within the EWATx testis, as compared to the SSNx and controls testes, which did not differ significantly from each other. From these data, it is concluded that EWAT, and not testicular innervation, is central to normal spermatogenesis.
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Estudi citològic i bioquímic del fluid epididimari de "Sus domesticus"Pruneda Sais, Anna 21 June 2006 (has links)
En aquest estudi s'ha determinat que al augmentar el ritme d'extraccions de semen es produeixen canvis en el patró d'absorció i secreció del fluid epididimari, que provoquen alteracions en la maduració epididimaria dels espermatozoides i un desenvolupament anòmal de la motilitat espermàtica.La concentració de glutamat i carnitina al fluid epididimari augmenten al llarg del conducte epididimari, alhora que la concentració de myo-inositol disminueix. El contingut de myo-inositol a l'interior dels espermatozoides disminueix, mentre que el contingut de glutamat augmenta a partir del caput distal i el contingut de carnitina no varia al llarg del conducte. S'ha determinat la presència de la ruta del poliol a l'epidídim de porcí. Els resultats obtinguts indiquen que la glucosa difon de la sang cap al fluid epididimari, és convertida a sorbitol per l'aldosa reductasa, i aquest sorbitol s'acumula al fluid luminal i és convertit a fructosa per l'acció de la sorbitol deshidrogenasa. / A high semen collection frequency brought about an altered resorption and secretion pattern of the epididymal fluid, which results in defective sperm maturation and abnormal development of sperm motility. In this study, it has been determined that in epididymal fluid the concentration of myo-inositol decreased in a proximo-distal direction, whereas intraluminal concentrations of L-carnitine and L-glutamate increased distally. The content of inositol in spermatozoa fell as they moved from the distal caput whereas sperm glutamate increased from the distal caput to more distal regions and carnitine content remained unchanged during epididymal transit. In this study, evidence for an operative polyol pathway was demonstrated in the porcine epididymis. The results found are consistent with diffusion of circulating glucose into the lumen, its conversion via aldose reductase to sorbitol which accumulates in the lumen and the action of sorbitol dehidrogenase on sorbitol to produce fructose.
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