By D. Jesper. Rochester Institute of Technology.
Storage vesicles have long been considered to be enlarged lysosomes engorged with storage material purchase eldepryl 5mg without a prescription. Lysosome proliferation and swelling could be an attempt to cope with the accumulation of storage material buy discount eldepryl 5mg on line. In reality order 5mg eldepryl with mastercard, the situation is much more complex buy 5mg eldepryl visa, and the exact identity and origin of these storage vesicles remain to be established. Significant stream of vesicular traffic coming into contact with lysosomes comes from the endocytic and autophagic pathways. Lysosome dysfunction may disrupt normal intracellular vesicle trafficking to or from lysosomes. One possibility is that late - 54 - Introduction endosomes and autophagosomes may accumulate because they are unable to fuse with the lysosome. A second possibility would be that late endosomes and amphisomes are able to fuse with the lysosome, producing hybrid vesicles. However, these hybrid vesicles loaded with material to be degraded would not be processed normally due to impaired capacity for lysosomal degradation. These possibilities are reinforced by morphological features characterizing storage vesicles. They might therefore be distinct from lysosomes which are usually small, highly dynamic, and contain homogeneous dense material. Examination of storage vacuoles by electron microscopy consistently revealed cytoplasmic vacuoles having a high degree of heterogeneity according to the affected cell type, but also within the same cell. Interestingly, different types of primary storage products can be associated with similar storage lesions. The high heterogeneity in the ultrastructure of storage vacuoles is consistent with a differential or uneven distribution of individual storage materials. Secondarily accumulating lipids can belong to any of the major classes: sphingolipids, cholesterol and phospholipids (Walkley and Vanier, 2009). This suggests that these two gangliosides are sequentially processed in physically separate compartments within the endo-lysosomal system. Another hypothesis would be that they are being generated by independent cellular processes, e. Cholesterol Unesterified cholesterol accumulation has been reported in the liver and spleen of all three types of Niemann-Pick diseases. Whereas increase in cholesterol levels is attributable to the primary genetic defect in Niemann-Pick type C, it is clearly a secondary event in Niemann-Pick types A and B that are caused by defective sphingolipid hydrolysis. Conversely, accumulation of unesterified cholesterol in Niemann-Pick type C secondarily affects sphingolipid sorting and transport. Interesting data come from a study performed in neurons from the mouse model of Gaucher disease. In these neurons, the levels of various phospholipids were elevated, which may account for the observed increase in neuritogenesis (Bodennec et al. Lipid rafts are specialized patches of membrane where cholesterol and sphingolipids accumulate. They represent signaling platforms that link receptor-ligand interactions at the cell surface with intracellular signal transduction events, and are sometimes referred to as glycosynapses. Lipid rafts are not restricted to the plasma membrane; they can also be transported in the endocytic pathway. It has been reported that cholesterol and sphingolipid excess results in impaired trafficking and accumulation of lipid rafts in the late endosomal compartment (Simons and Gruenberg, 2000 and discussed in the next paragraph). As certain proteins selectively reside in raft membranes, raft-associated proteins might become inappropriately sequestered, preventing them from trafficking to their normal sites of function. Mislocalization of raft proteins would have possible consequences on cell signaling. Sphingolipids and cholesterol would be expected to reside in the same compartment in such context. Alterations of intracellular trafficking Since the fusion of lysosomes with late endosomes or autophagosomes is the terminal step of endocytosis and macroautophagy, respectively, a global lysosome malfunctioning can affect these pathways. When added exogenously, a short analogue of the sphingolipid lactosylceramide (LacCer) is transported to the Golgi in normal conditions. In the group of sphingolipid- storage diseases, the underlying mechanism involves the close correlation between sphingolipid and cholesterol levels that we just saw. Based on the observation that - 58 - Introduction Golgi targeting is restored upon cholesterol depletion, it has been postulated that altered intracellular distribution of cholesterol secondary to primary sphingolipid storage in turn leads to defective sphingolipid trafficking (Puri et al. Cholesterol homeostasis is itself linked to the activity of Rab proteins (Choudhury et al. Golgi targeting is dependent on several Rab proteins mediating vesicle trafficking along the endocytic pathway, implying that LacCer likely travels from late endosomes, and possibly from lysosomes to the Golgi. The presence of autophagosome accumulation can thus result either from autophagy overactivation, or a from a defective autophagosome maturation. A hypothesis that reconciles this apparent discrepancy between a block and an induction of autophagy is that lysosomal storage may affect fusion efficiency between autophagosomes and lysosomes, leading to a block of autophagy. Compensatory feedback mechanisms would in turn be activated, leading to activation of autophagy. Accumulation of extracellular storage compounds would lead to non-physiologic activation of these receptors. Endocytosis of activated receptor complexes represents a mean to terminate signaling. Means by which the endocytic process can regulate signaling mechanisms do not only involve internalization of receptor-ligand complexes or regulation of the composition of membranes (e. The major sphingolipid that accumulates in this disease, glucosylceramide, directly modulates and overactivates this receptor (Vitner et al. Finally, in Batten disease, calcium homeostasis is altered by inhibition of a plasma-membrane voltage-gated calcium channel (Luiro et al. Calcium plays an important role in excitable cells such as neurons, where it induces immediate responses such as neurotransmitter release, as well as long-term responses via activation of cell signaling pathways. In type 1 Gaucher disease, acid-beta- glucosidase storage in macrophages leads to macrophage activation and release of cytokines and chemokines. Activated astrocytes and microglia produce potentially neurotoxic chemokines and cytokines. Whereas the association of chronic neurodegeneration and inflammation is well established, the causative links between these events is debated. Numerous studies indicate that the inflammatory process may trigger acute neurodegeneration and/or dysmyelination, exacerbating pathogenesis. The exact mechanisms that lead to macrophages and microglia activation are unknown. Storage in these cells could induce mislocalization of key proteins to the lysosome, resulting in disrupted cell signaling. One trigger could be the clearance of - 63 - apoptotic neurons by phagocyting microglia. Oligodendroglia the myelin producing cells- can be affected, leading to myelinopathy. Affected neurons contain storage vacuoles in the cell body and in dendrites, but not typically in axons.
Abdominal pain may be a feature of a number of Causes may range from common normal physiologic extra-abdominal conditions including heart attack order 5 mg eldepryl with mastercard, processes to life-threatening emergencies eldepryl 5 mg online. There are pneumonia buy 5 mg eldepryl visa, testicular torsion generic eldepryl 5 mg with amex, and a variety of meta- many factors that contribute to the sensation and per- bolic disorders (e. The sensation of pain is produced by mechanical Although most episodes of abdominal pain are stimuli, chemical stimuli, or a combination of both. The due to mild self-limited conditions, it is essential to be most common mechanical stimulus is stretch. There are able to discern the signs and symptoms that represent stretch receptors located in the muscular layer of the potential emergencies and require immediate interven- hollow organs (gastrointestinal, urinary, and biliary tion. Medical attention should be sought immediately tracts), mesentery (membranous attachment of intra- when abdominal pain is accompanied with any of the abdominal organs to the posterior abdominal wall), and following alarm signs or symptoms: red blood in the in the capsule (membranous outer covering) of solid stool; maroon stool; black tarry stool; fever; sudden organs (e. Thus, any process onset of constipation or bloating; persistent vomiting; which leads to distention, stretching, and traction may vomiting red blood or coffee grounds; history of generate abdominal pain. Chemical stimuli can increase recent abdominal trauma; known or suspected preg- the sensitivity of these pain receptors. A thorough history and physical examination is the Broadly speaking, abdominal pain may be pro- first crucial step in the assessment of abdominal pain. Other characteristics include the quality of suprapubic area (below the umbilicus and above the the pain (e. A detailed menstrual history in female may represent acute cholecystitis (inflammation of the patients should also be obtained. Pain in the left upper quadrant The description of the onset of pain distinguishes may be due to impaired blood flow to the spleen or left acute abdominal pain, lasting hours to days, from colon. Pain caused by appendicitis often begins in the chronic pain, occurring over a period of weeks to periumbilical area and then settles in the right lower months. Pain due to disorders involving the kidneys, ruptured ectopic pregnancy, or kidney stones may ovaries, or fallopian tubes is usually perceived on the cause pain that is sudden in onset and reaches peak same side of the abdomen as the affected organ. Acute abdominal pain associated with be seen in urinary tract infections, pelvic inflammatory passing blood either from the upper or lower gastroin- disease, and endometriosis. Diffuse abdominal pain may repre- Chronic abdominal pain occurring over a period of sent infectious peritonitis, appendicitis, inflammatory weeks to months in the absence of any alarm signs or bowel disease, or a perforated duodenal ulcer. Chronic intermittent pain may, tendency for pain to be located at a site remote from the at times, be particularly difficult to diagnose whereas affected organ. For chronic persistent pain usually has an identifiable instance, pain from an inflamed gallbladder may some- cause, such as chronic pancreatitis, disseminated malig- times be perceived in the right shoulder. Pain that is temporally associated role in the physicians evaluation of abdominal pain and with a womans menstrual cycle may be due to is often more informative than laboratory studies. Chronic pain associated clinician assesses the general appearance of the patient with anorexia and weight loss may indicate an underly- along with the vital signs. A history of abdominal pain associated habit, are often precipitated or worsened by stress or with unresponsiveness, shock, or cardiac arrest suggests anxiety. Traditionally, obstruction), whereas hyperactive or high-pitched the abdomen is divided into four parts, referred to as tinkling sounds suggest intestinal obstruction. Guarding 51 Abortion (involuntary abdominal muscular wall contraction) on of other pelvic surgical procedures. The offer a variety of procedures for the diagnosis and treat- abdomen is also examined for the presence of masses as ment of abdominal pain including upper and lower well as liver and spleen findings such as enlargement, endoscopy (insertion of a flexible tube containing a nodularity, or tenderness. In women with lower abdom- camera into the mouth or rectum) of the digestive and inal pain, a pelvic examination should be performed to pancreasbiliary tracts, motility studies, and pH (acid) assess potential uro-gynecological causes. At times, the involvement of an anes- Laboratory and radiologic studies can provide thesiologist or other pain management professional is additional information in making the diagnosis. They are skilled in the management of pain tests ordered should reflect the clinical suspicion. If there appears to be a psy- should be considered in all women of reproductive age chiatric component to abdominal pain, referral to a with lower abdominal pain. Philadelphia: Lippincott, plastic, and vascular lesions, as well as for identifying Williams & Wilkins. Other potential radiologic examinations available, depending Suggested Resources on the clinical circumstances, include angiography, con- U. Medical abor- Obstetrician/gynecologists are skilled in the evalu- tion (abortion induced by the use of medications) has ation of women with a suspected gynecologic cause recently become an option in this country. In most of pain and perform a wide variety of diagnostic and medical abortions, expulsion of the pregnancy occurs at curative procedures such as transvaginal ultrasound, home. About 1% of women require surgical evacuation diagnostic and therapeutic laparoscopy, and a number to complete the process. It is usually a single-step process that requires who are having a medical abortion require an emer- one visit to the practitioner. In early pregnancy (less gency dilation and curettage because of heavy bleed- than 7 weeks), a small flexible plastic cannula (56 mm) ing (1%). Postabortion follow-up with a practitioner is is inserted into the uterus under sterile conditions. In some studies, only half of pain relief is provided by injecting local anesthetic into the women who thought they had aborted actually the cervix and administering intravenous sedation and had done so. This facilitates Misoprostol is the most common medication used the use of a cannula to extract the fetus and placenta at in medical abortion. It causes softening of the cervix and uterine con- increase with gestational age and the use of general tractions, resulting in the termination of a pregnancy. Risks include hemorrhage, infection, and Because misoprostol is potentially teratogenic (it can perforation of the uterus if a surgical instrument slips cause physical malformations of the fetus), a surgical through the uterine wall. Uterine perforation can cause abortion must be performed in the event of a continu- bladder, bowel, or vascular injury necessitating further ing pregnancy. The most common complication is Mifepristone is a progestin-like structure that uterine infection (0. This halts the process of implantation (attach- visits, and there is a potential need for emergency inter- ment of the embryo to the uterine wall). The earlier the gestational age is, the higher the Repeated use of medical termination has not been complete abortion rate. However, there is no ranges from 92 to 96% if medication is begun before medical basis to believe that repeated medical abortion 56 days. Most med- ication regimens require patients to be no more than 50 days pregnant (as calculated from the first day of the last menstrual period). Complicated systems such as applica- tion for Medicaid present perceived and real barriers in literacy and native language. Further, workforce studies underscore the lack of providers who speak the lan- guage and are from the same culture as the populations Access to Health Care Access to health care they serve. Thus, barriers are influenced by provider has dominated the health policy scene for several and patient factors. In the early 1990s, national legislation, uni- versal access to health care, was introduced by President Clinton and the Congress as a way to provide Culture health security for all Americans. Health care providers and facilities that do not The effort, although unsuccessful, has kept the problem understand the cultural expectations and norms of the of health care access on the public agenda. Initially, ficulty in achieving compliance with necessary medical the premise was access to physicians and hospitals.
We conclude that Iberian lynx are induced ovulators as described for many other felid species (Brown and Wildt buy 5mg eldepryl with mastercard, 1997) discount 5mg eldepryl visa. Thus eldepryl 5 mg overnight delivery, if mating occurs best 5 mg eldepryl, corpus luteum (cl) formation is evident by elevated estrogens and ultrasound examination (Gritz et al. The positively tested animals were all between day 32 and 56 of pregnancy, of a 63-66 day gestation period (Vargas et al. The animal whose plasma yielded negative WitnessRelaxin test results, was at day 32 after her frst mating, although later she was proven to be pregnant. Only when urine samples were concentrated by ultrafltration at least 50x, a weak relaxin positive reaction was observed between day 29 and 46 of the pregnancy (n=17). These failed pregnancy diagnosis might be explained by the ongoing degradation of relaxin within the urine samples (late collection) and/or insuffcient level of the ultrafltration procedure. Thus, the urinary relaxin was still under the detection level of WitnessRelaxin test. In contrast to urinary progestagens, estrogens refect cl formation after ovulation. Furthermore, the observed increase of urinary E2 after mating and during late pregnancy suggest either an E2 secretion from the lynx placenta and/or a pregnancy-specifc enhanced luteal secretion of estrogen, a point for additional study. In addition, pregnancy diagnosis is attainable by applying the Witness Relaxin bench top test, if blood plasma or highly concentrated urine samples are used. Relaxin can be detected in a certain period during pregnancy, which ranges between 34 to 50 days after mating for blood plasma, and day 37 to 46 post-mating days for urine samples, respectively. Rodrguez) and volunteers at the El Acebuche Breeding centre for their every day engagement within the Iberian Lynx conservation Breeding Programme. We appreciate the support of the Environmental council of the Andalusian Government and the Spanish Ministry of the Environment. Determination of the source of immunoreactive Journal of Reproduction and Fertility 51, 303-312. Determination comparative Aspects of Steroid-Hormone Metabolism of free and conjugated oestrogens in peripheral blood plasma, and Ovarian Activity in Felids, Measured non-invasively in feces and urine of cattle throughout pregnancy. Immunoassay of human chorionic gonadotropin, comparative Endocrinology 149, 151-158. In vitro release of progesterone and estrone by the porcine placenta throughout gestation. Use of synthetic canine relaxin to develop hormone metabolism in the two sister taxa, in: Vargas, A. The excretion of steroid hormone metabolites ultrasonographic examination of the female urogenital in bile and feces. Interdisciplinary Methods in the Iberian lynx (Lynx pardinus) conservation Breeding Programme, in: Vargas, A. Validation of a minimally invasive blood-sampling technique for the analysis of hormones in domestic rabbits, Oryctolagus cuniculus (Lagomorpha). Mediante las tcnicas de laboratorio empleadas en este estudio se consigui validar la metodologa para detectar los andrgenos fecales en los machos, y los anlisis revelaron un incremento estacional claro en los niveles de andrgenos antes y durante la poca de reproduccin. La validacin de ensayos para estrgenos y progestgenos no fue completamente convincente, aunque s informativa. En las hembras se observ un aumento signifcativo en los niveles de estrgenos durante la poca reproductora. La validacin del ensayo no fue concluyente en parte debido a la persistencia inusualmente prolongada de cuerpos lteos, lo que posiblemente produzca distintos perfles hormonales en las hembras de lince comparadas con las de otros mamferos. Asimismo, se valid una prueba para detectar glucocorticoides en heces de machos y hembras. Encontramos indicios preliminares de que las hembras tienen una respuesta fsiolgica ms marcada ante el estrs que los machos, aunque esto no signifca necesariamente que las hembras sean ms sensibles al estrs. El estrs crnico (por ejemplo, por translocacin o contencin) parece suprimir la expresin de andrgenos en los machos. Sera necesario llevar a cabo ms estudios para obtener un conocimiento ms claro sobre cmo afectan los factores estresantes presentes en el entorno a la reproduccin del lince canadiense y, por ende, a su tamao poblacional. Un mayor conocimiento sobre la fsiologa reproductiva del lince podra ayudar a mejorar las prcticas de conservacin. Pa l a b R a s c l a v e Hormonas fecales, estacionalidad, estrs ab s t R a c t Knowledge about the reproductive physiology of lynx could help improve conservation practices. The goal of this study was to validate fecal hormone metabolite assays for Canada lynx and develop a basic understanding of their reproductive physiology. Fecal androgen assays were validated for males, and analysis revealed a clear seasonal increase in androgen expression immediately prior to and during the breeding season. The validation of fecal estrogen and progestagen assays for females was not entirely convincing, but nevertheless informative. A signifcant rise in fecal estrogens was observed during the breeding season for females. Assay validation may be partially confounded by the unusually long persistence of corpora lutea in Lynx species, which could produce different hormone profles compared to other female mammals. Lastly, a fecal glucocorticoid metabolite assay was validated for both males and females. We found preliminary evidence that females may have a more pronounced physiological stress response than males, although this does not necessarily imply that females are more sensitive to stress. Further research is needed to gain a clearer understanding of how environmental stressors may impact Canada lynx reproduction, and thereby affect their population size. In response to this decline, the state of colorado initiated a lynx reintroduction effort in 1999 (see Shenk, this book). However, poor reproductive success of reintroduced individuals has threatened the success of this effort. C There are two characteristics of lynx reproduction that may contribute to their diminishing population size and hinder reintroduction efforts. First, canada lynx are highly seasonal breeders; they have only one chance per year to reproduce (Poole, 2003). They breed from late February to early April and give birth primarily in May, with a gestation period of 60-70 days (nowak, 1999; Ruggiero et al. Even in the southern part of their range and in captivity, females only breed once per year and most kittens are born in May. Although the breeding season lasts about two months, individual females may have a much more restricted window of mating opportunity. Little is known about estrus in wild lynx, but behavioral indicators suggest that females are only receptive for a short period. Mating pairs only remain together for several days and females presumably mate with only one male (Ruggiero et al. There is no published information about the duration or the length of estrus in captive or wild canada lynx (nowak, 1999).
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