By R. Ketil. Saint Leo University.
Reproductive steroid hormones and ovarian activity in felids of the Leopardus genus buy malegra fxt with paypal. Reproduction and pre-dispersal survival of Iberian lynx in a subpopulation of the Donana national Park discount malegra fxt 140mg amex. Relationships during pregnancy purchase malegra fxt now, parturition order malegra fxt with mastercard, lactation and the post-partum estrus. Responsiveness of ovaries to exogenous gonadotrophins and laparoscopic artifcial insemination with frozen-thawed spermatozoa in ocelots (Felis pardalis). Manejo del Lince Ibrico en cautividad / Husbandry of the Iberian lynx in captivity, in: Biodiversidad, F. Interdisciplinary methods in the Iberian lynx (Lynx pardinus) conservation Breeding Programme, in: Vargas, A. The causes of physiological suppression among female meerkats: A role for subordinate restraint due to the threat of infanticide? Comparison of hormone metabolism in the two sister taxa Anlisis de esteroides sexuales en heces de lince ibrico y de lince euroasitico en cautividad. Se escogi al lince euroasitico como modelo para el lince ibrico (Lynx pardinus) con el fn de proporcionar la necesaria validacin biolgica de los anlisis de hormonas en heces que se realizasen posteriormente en el Programa de conservacin Ex situ del lince ibrico. Durante un periodo de tres aos, se tomaron muestras fecales de cuatro machos y 10 hembras de lince euroasitico mantenidos en cautividad en una estacin de investigacin ubicada cerca de Mosc. Los metabolitos de testosterona en heces refejan la actividad testicular en machos de lince euroasitico (estacionalidad) y de lince ibrico (madurez sexual), mientras que los metabolitos de progestgenos en heces no son efcaces para diagnosticar el celo o la gestacin en hembras de lince euroasitico. Por lo tanto, es necesario desarrollar mtodos alternativos, tales como el seguimiento de las hormonas en la orina. We chose the Eurasian lynx as a model for the Iberian lynx (Lynx pardinus) to provide the necessary biological assay validation to be applied in the Ex situ Programme established for this endangered species. Fecal samples were collected over a three year period from four male and 10 female Eurasian lynx maintained at a research station near Moscow. Fecal testosterone metabolites refect the testicular activity in male Eurasian (seasonality) and Iberian lynx (sexual maturity), whereas fecal progestagen metabolites are ineffective for estrous and pregnancy diagnosis in both lynx species. The Iberian lynx captive breeding programme, however, depends on a reliable and non- invasive pregnancy diagnosis to prevent peri-natal losses of cubs. Therefore, alternative approaches, like monitoring urinary hormones, need to be developed. All lynx species are distributed over the northern Hemisphere in Europe, Asia and America. The Iberian lynx was always restricted to the Iberian Peninsula south of the Pyrenees (calzada et al. All four lynx species have some general common features (Table 1), which are typical of the Felidae (Breitenmoser et al. Data presented in this table are mostly based on skinned carcasses collected from trappers or on reports of captive animals (Hayssen et al. All except for the bobcat are monestrous breeders, starting their mating period in January. The Iberian lynx has the narrowest breeding season, lasting for about one month (Palomares et al. It has also the shortest gestation length and can have more than one litter per year. The gestation length is approximately 65-70 days for the Eurasian lynx and 63-66 days for its Iberian counterpart (Vargas et al. ParameTers o f r e P r o d u c T i o n in f o u r ly n x Body length 80-130 cm 75 100 cm 90-100 cm 72 98 cm s P ec i e s. Pa r m e T r o s d e r e P r o d u c c i n en c u a T r o esPecies Neonatal weight 250-360 g 150-220 g 200 g 112-226 g d e l i n c e. Oestrus length 2-7 d 2-7 d 2 d Cycle length - - - 44 d Gestation 68-72 d 63-66 d 60-65 d 50-60 d Lactation 3m 3-4m 3m (solid food) (6 w) (8-9 w) (7-8 w) Litter/year 1 1 1 >1 Breeding season Jan-Apr Jan-Feb Jan-Feb Jan-July considering the tight relationship between both sister taxa (Johnson et al. A prerequisite for the establishment of methodology for non-invasive hormone monitoring is the biological validation of the analytical method. As this validation is impossible to perform in the highly endangered Iberian lynx, the Eurasian lynx was suggested as a model for the establishment of hormone monitoring in captive male and female lynxes. The aim of the presented study was to characterize relevant steroid hormone metabolites in captive Eurasian lynx to assist with non-invasively monitoring of male and female reproductive performance. The ultimate goal was to provide a biological validation of fecal hormone assays to be applied in the Iberian lynx captive breeding programme. The animals were kept within six enclosures (74 m ) and in one large fenced enclosure (7. Animals were housed separately and males and females were put together only for mating. Fecal samples were collected monthly throughout a two-year period and stored at 20 c within 1 h after defecation until analyses. From February to April (prospective mating season) the frequency of collection was increased to 1-2 times per week. For comparative assessment of hormone metabolites, fecal samples from captive Iberian lynxes were provided from the Iberian Lynx captive Breeding center, El Acebuche, in Doana national Park (Vargas et al. After centrifugation (15 min at 1200 g) the supernatant was transferred into a new tube. All hormone measurements were carried out in duplicates to assess the coefficient of variation. Results were expressed as immunoreactive steroid metabolites in g/g of fecal wet weight. The cross-reactivitys of both antibodies and their inter- and intra-assays as coeffcients were as described before (Dehnhard et al. Ra d I o m e t a b o l I s m s t u d y To identify relevant progesterone metabolites we carried out a radiometabolism study. Following the radiolabelled injection, all excreted fecal samples were separately collected from the enclosures immediately after defecation during a 4-day period, placed in a plastic bag and stored at -20 c. Aliquots of each sample were extracted for gestagen determination and for radioactivity counting. All radioactive counting was conducted in a Perkin Elmer MicroBeta Trilux counter (Perkin Elmer, Germany). Metabolites were separated with a methanol:water mixture (78:22) at a fow rate of 1 ml/min. Metabolites were separated with an acetonitril: water mixture (43:57) at a fow rate of 1 ml/min. According to the manufacturer the functional sensitivity for the T assay on this system is 0. A test for parallelism was performed for feces from both the Eurasian and the Iberian lynx. Ra d I o m e t a b o l I s m s t u d y The testosterone radiometabolism study was performed with a solution (0. Sedation and sample collection was performed as described for females (see above). Aliquots of each sample were extracted for testosterone determination and radioactivity counting. To prove whether testosterone or its metabolites were conjugated to glucuronides or sulfates, the fecal extract was also subjected to enzyme hydrolysis and solvolysis (Jewgenow et al. A linear gradient was generated at a fow rate of 1 ml per min: 011 min, 60% to 75% methanol; 11-20 min, 75%; 20-25 min, 75% to 100% methanol. The statistical procedures were performed with the software programme Instat Version 3 (Graphpad Software Inc. Re s u l t s a n d d I s c u s s I o n se a s o n a l P a t t e R n s o F R e P R o d u c t I o n Fe m a l e R e P R o d u c t I o n : e s t R o g e n a n d g e s t a g e n m e t a b o l I t e s We analysed fecal samples of pregnant (n=15) and pseudo-pregnant (n=7) female Eurasian lynxes during a 3-year study period. There is a tendency towards higher progestagen and estrogen metabolite concentrations during pregnancy. However, no distinct differences between profles from pregnant (a) and pseudo- pregnant (b) females were obtained. As shown for pregnant and pseudopregnant females, a distinct estrogen peak was absent at mating time.
The dierent variants rise and fall in abundance according to the rate of switching between variants buy malegra fxt 140 mg otc, the time lag in the expansion of parasite lineages expressing a particular variant buy 140mg malegra fxt amex, and the time laginthehost immune response to each variant discount malegra fxt uk. This host variability can strongly aect the relative success of antigenic variants as they attempt to spread from host to host purchase malegra fxt with a visa. Hosts also dier in mi- nor ways in other genetic components of specic recognition. These quantitative dierences in the timing and intensity of immune reactions provide an interesting modelsystemforstudying the genetics of regulatory control. Each host typically retains the ability to respond quickly to antigens that it encountered in prior infections. This memory pro- tects the host against reinfection by the same antigens, but not against antigenic variants that escape recognition. The distribution of memory proles in the host population determines the ability of particular anti- genic variants to spread between hosts. Hosts retain dierent kinds of immunological memory (antibody versus T cell), which aect dierent kinds of parasites in distinct ways. The genetic structure of nonantigenic loci provides information about the spatial distribution of genetic variability, the mixing of parasite lineages by transmission between hosts, andthemixing of genomes by sexual processes. The genetic structure ofantigenic loci can additionally be aected by the distribution of host immunological memory, because parasites must avoid the antigen sets stored in immunological memory. Host selection on antigenic sets could potentially structure the parasite population into distinct antigenic strains. Finally, each host forms a separate island that divides the parasite population from other islands (hosts). This island structuring of parasite populations can limit the exchange of parasite genes by sexual processes, causing a highly inbred structure. Island structuring also means that each host receives a small andstochastically variable sample of the parasite population. Stochastic uctuations may play an important role in the spatial distribution of antigenic variation. Im- munological assays compare the binding of parasite isolates to dier- ent immune molecules. The reactions of each isolate with each immune specicity form a matrix from which one can classify antigenic variants according to the degree to which theysharerecognition by immunity. Alternatively, one can classify isolates phylogenetically, that is, by time since divergence from a common ancestor. Concordant immunological and phylogenetic classications frequently arise because immunological distance often increases with time since a common ancestor, reecting the natural tendency for similarity by common descent. Discordant pat- terns of immunological and phylogenetic classications indicate some evolutionary pressure on antigens that distorts immunological similar- ity. Thiswell-studied vi- rus illustrates how one can measure multiple selective forces on partic- ular amino acids. Selective forces on amino acids in viral surface mole- cules include altered binding to host-cell receptors and changed binding to host antibodies. The selective forces imposed by antibodies and by at- tachment to host-cell receptors can be varied in experimental evolution studies to test their eects on aminoacidchange in the parasite. The amino acid substitutions can also bemapped onto three-dimensional structural models of the virus to analyze how particular changes alter binding properties. Experimental evolution has shown how altering the host species favors specic amino acid changes intheinuenzasurface protein that binds to host cells. Experimental manipulation of host-cell receptors and antibody pressure can be combined with structural data to under- stand selection on the viral surface amino acids. These mechanistic analyses of selection can be combined with observations on evolution- arychange in natural populations to gain a better understanding of how selection shapes the observed patterns of antigenic variation. The host T cells can potentially bind to any short peptide of an intracellular parasite, whereas antibodies typically bind only to the surface molecules of parasites. T cell binding to parasite peptides depends on a sequence of steps by which hosts cut up parasite proteins and present the resulting peptides on the surfaces of host cells. Parasite proteins may be shaped by opposing pressures on physiological performance and es- cape from recognition. A phylogenetic classication of sequences provides a his- torical reconstruction of evolutionary relatedness and descent. Against the backdrop of ancestry, one can measure how natural selection has changed particular attributes of parasite antigens. For example, one can study whether selection caused particular amino acids to change rapidly or slowly. The rates of change for particular amino acids can be com- pared with the three-dimensional structural location of the amino acid site, the eects on immunological recognition, and the consequences for binding to host cells. The changes in natural populations can also be compared with patterns of change in experimental evolution, in which one controls particular selective forces. Past evolutionary change in pop- ulation samples may be used to predict which amino acid variants in antigens are likely to spread in the future. The last chapter recaps some interesting problems for future research that highlight the potential to study parasites across multiple levels of analysis. I had initially intended this book to avoid such jargon, so that any reasonably trained biologist could read any chapter without getting caught up in technical terms. The vertebrate immune system has many specialized cells and mole- cules that interact in particular ways. One has to talk about those cells and molecules, which means that they must be named. I could have tried a simpler or more logically organized naming system, but then I would have created a private language that does not match the rest of the literature. In this chapter, I introduce the major features of immunity shared by vertebrates. I present enough about the key cells and molecules so that one can understand how immune recognition shapes the diversity of parasites. I have not attempted a complete introduction to immunology, because many excellent ones already exist. I recommend starting with Sompayracs (1999) How the Immune System Works,whichisashort, wonderfully written primer. Mimss texts also pro- vide good background because they describe immunology in relation to parasite biology (Mims et al. Nonspecic recognition depends on generic signals of par- asites such as common polysaccharides in bacterial cell walls. The second section introduces specic immunity, the recognition of small regions on particular parasite molecules. Specic recognition oc- curs when molecules of the host immune system bind to a molecular shape on the parasite that is not shared by other parasites. Other times, dier- ent parasite genotypes vary in molecular shape, so that the host mole- cules that bind specically to one parasite molecule do not bind another parasite molecule that diers by as little as one amino acid. The small region of the parasite molecule recognized by the host is called an epitope. Antigenic variation occurs when a specic immune response against one antigenic molecule fails to recognize a variant antigenic mol- ecule. An- tibodies are globular proteins thatghtinfectionbybinding to small regions (epitopes) on the surface molecules of parasites. An individual can make billions of dierent antibodies, each with dierent binding specicity. Diverse an- tibodies provide recognition and defense against dierent kinds of par- asites, and against particular parasites that vary genetically in the struc- ture of their surface molecules. Antibodies bind to surface molecules and helptoclearparasitesoutside of host cells. T cells bind to parasite peptides digested in infected cells and presented on the infected cells surface, helping to clear intracellular infections. The nal section summarizes the roles of antibodies and T cells in specic immunity. Host cells have several surface molecules that shut o complement attack, causing complement to be directed only against invading cells.
Human degenerative valve disease is associated with up-regulation of low-density lipopro tein receptor-related protein 5 receptor-mediated bone formation buy cheap malegra fxt. Regulation of the selective uptake of cholesteryl esters from high density lipoproteins by sphingomyelin buy malegra fxt 140 mg free shipping. Differential effects of the cyclin-dependent kinase inhibitors Kip1) discount 140mg malegra fxt free shipping, p21(Cip1) order malegra fxt no prescription, and p16(Ink4) on vascular smooth muscle cell proliferation. Pravastatin has cholesterol-lowering independent effects on the artery wall of atherosclerotic mon keys. Identification, characterization, and comparison of the calmodulin-binding domains of the endothelial and inducible ni tric oxide synthases. Alterations in membrane cholesterol that affect structure and function of caveolae. Native low-density lipoprotein induces endothelial nitric oxide synthase dysfunction: role of heat shock protein 90 and caveolin-1. Synergistic up-regulation of vascular endothelial growth factor expression in murine macrophages by adenosine A(2A) receptor agonists and endotoxin. In duction of vascular smooth muscle alpha-actin gene transcription in transforming growth factor beta1-activated myofibroblasts mediated by dynamic interplay be tween the Pur repressor proteins and Sp1/Smadcoactivators. Association of coronary risk fac tors and use of statins with progression of mild valvular aortic stenosis in older per sons. Presence of oxidized low density lipoprotein in nonrheumaticstenotic aortic valves. Cardiovascular features of homozy gous familial hypercholesterolemia: analysis of 16 patients. Quantitative structur al analysis of collagen in chordae tendineae and its relation to floppy mitral valves and proteoglycan infiltration. Apparently normal mitral valves in patients with heart failure demonstrate biochemical and structural derangements: an extracellular matrix and echocardiographic study. Glycosaminoglycans and proteoglycans in normal mitral valve leaflets and chordae: association with regions of tensile and compressive loading. Estrogen regulation of hu man osteoblastic cell proliferation and differentiation. Low turnover osteodystrophy and vascular calcification are amenable to skeletal anabolism in an animal model of chronic kidney disease and the metabolic syndrome. Role of the cholesterol biosynthetic pathway in osteoblastic differentiation of marrow stro mal cells. Lipid oxidation products have opposite effects on calcify ing vascular cell and bone cell differentiation. A possible explanation for the paradox of arterial calcification in osteoporotic patients. Calcification of vascular smooth mus cle cell cultures: inhibition by osteopontin. Lymphoid enhancer factor-1 and beta-catenin inhibit Runx2-dependent transcriptional activation of the osteocalcin promoter. Dkk-1-derived Synthetic Peptides and Lithium Chloride for the Control and Recovery of Adult Stem Cells from Bone Marrow. The canonical Wnt signal ing pathway promotes chondrocyte differentiation in a Sox9-dependent manner. Identification and characterization of calcifying valve cells from human and canine aortic valves. Atorvastatin Inhibits Hypercholesterolemia-Induced Calcification in the Aortic Valves via the Lrp5 Receptor Pathway. Treatment with simvas tatin suppresses the development of experimental abdominal aortic aneurysms in normal and hypercholesterolemic mice. Statins but not angiotensin-con verting enzyme inhibitors delay progression of aortic stenosis. Rosuvastatin affecting aortic valve endotheli um to slow the progression of aortic stenosis. Abnormal aortic valve develop ment in mice lacking endothelial nitric oxide synthase. Anionic growth factor activity from car diac valve endothelial cells: Partial purification and characterization. Porcine cardiac valvularsubendothelial cells in culture: cell isolation and growth characteristics. Role of human valve interstitial cells in valve calcification and their response to atorvastatin. Glycoproteins synthesized by cultured cardiac valve en dothelial cells: unique absence of fibronectin production. Wnt/beta-cate nin signaling stimulates chondrogenic and inhibits adipogenic differentiation of peri cytes: potential relevance to vascular disease? Targeting of nitric oxide synthase to endothelial cell caveolae via palmitoylation: implications for nitric oxide signaling. Hypercholesterole mia decreases nitric oxide production by promoting the interaction of caveolin and endothelial nitric oxide synthase. Human pulmonary valve progenitor cells exhibit endothelial/mesenchymal plasticity in response to vascular endothelial growth fac tor-A and transforming growth factor-beta2. Syn ergy, redundancy and pleiotropy of cytokines affecting the regulation of erythropoie sis. The universal properties of stem cells as pinpoint ed by a simple discrete model. Pathogenesis of calcific aortic valve disease: a disease process comes of age (and a good deal more). Menopause: endocrinology and symptoms Menopause is a physiologic process in women that occurs around 45-55 years old, which is defined as permanent cessation of menstruation by one year in row . The age of meno pause depends on multiple factors such as number of ovules from the female at birth, the frequency of loss of these ovules through her life and the number of ovarian follicles re quired maintaining the menstrual cycle. The diagnosis of menopause is retrospective and is established after a year without menses , and their symptoms may have different intensi ty for each woman . Hot flushes are one of the main symptoms associated with menopause and occur in more than 75% of menopausal, consisting of intense episodes of heat that begins on chest and spreads to face, sweating, and flushing of face. The mechanism of hot flushes is not clear, however, it is known that hypothalamus, pituitary gonadotropin releasing hormone and gonadotrophins may be involved in hot flushes . Another fre quent symptom is an oral dryness and intense burning sensation that affects mainly the tongue and sometimes lips and gums . On the other hand decreases the content of collagen and elastic fibers of the skin, so that it becomes thinner and brittle losing elasticity and firmness. The epidermis thins, increases water loss and reduces the number of blood vessels, compromising the supply of oxygen and nutrients . Additionally aging is associated with a natural decline in physiological functions, including a loss of muscle mass and strength. Another alteration that occurs is the osteoporosis, which is defined as a skeletal disorder characterized by decreased bone density and an increased risk of fractures [17, 18]. Other disorders such as obesity and metabolic syndrome also occurs at menopause, suggesting that menopause may be the trigger of the metabolic syndrome at that stage of life [27, 28]. Estrogens are synthesized from different androgen precursors such as androstenedione and testosterone, yielding as products estrone and 17-estradiol, respectively. The toxic effect of 4-hydroxyestrogens probably is prevented under normal conditions intracel lular defense mechanisms. Oxygen free radicals can be removed immediately transformed into water by enzymes such as catalase and superoxide dismutase and antioxidant vitamins 294 Oxidative Stress and Chronic Degenerative Diseases - A Role for Antioxidants such as ascorbic acid and alpha tocopherol, quinone themselves can be inactivated by sulfo compounds, such as glutathione . Serum -glutamyltransferase, glutathione and malondialdehyde levels in the pre- and postmenopausal women . Data showing departures from normality are expressed as median values with the respective lower and upper quartile. Another finding is the lipoperoxide level which was significantly increased in perimeno pausal women (Table 3).
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