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Involution
Kinds of Involution Selected AbstractsPost-Partum Involution of the Canine Uterus , Gross Anatomical and Histological FeaturesREPRODUCTION IN DOMESTIC ANIMALS, Issue 2009DC Orfanou Contents We aimed to study the normal puerperium in the bitch. Ovariohysterectomy was performed in nine bitches, each at a different day after normal whelping; their genital tract was subject to gross anatomical examination, as well as to histological examination and electron microscopy scanning. Corpora albicans were evenly distributed in the left and right ovaries and placental sites were evenly distributed among left and right uterine horns. Placental sites were initially of dark green to grey colour, later becoming dark brown; their length and height progressively decreased. Height of the myometrium and diameter of the uterine glands progressively decreased. Trophoblast-like cells were consistently observed at the placental sites and on the surface of the interplacental areas, at all time points where hysterectomy had been performed. It is suggested that involution of the canine genital tract can last up to 3 months and is slow. Continuous (up to D84 post-partum) presence of prominent placental sites should be considered a normal feature of canine uterine post-partum involution. [source] Involution of thymus and lymphoid depletion in mice expressing the hTNF transgeneAPMIS, Issue 1 2004HEIDI GLOSLI Tumour necrosis factor (TNF) is involved in the pathogenesis of several diseases. In mice, human TNF signals only through p55, one of two murine TNF receptors. We here report a study of growth, viability and morphological alterations in transgenic mice expressing a low constitutive and tissue-restricted level of human TNF in vivo. The transgene was expressed solely in T cells. The transgenic mice showed a marked failure to thrive and a rapid cellular depletion in spleen and thymus. Slight fibrosis was seen in most tissues investigated, in addition to immature adipose tissue and irregular lymphocytic areas. Serum levels of hTNF were only slightly increased in the transgenic mice, enough, however, to cause an inflammatory reaction. All the symptoms were abrogated by an inhibitory hTNF antibody, demonstrating the essential role of hTNF in this phenotype. Transgenic mice constitute a multidimensional system allowing observation of disease processes over time in all tissues. The effects of hTNF were seen first and foremost in the lymphoid organs of the transgenic mice, verifying their cells as major targets at low levels of hTNF expression in the T-cell compartments. Chronic, low levels of TNF expression cause profound disturbances in lymphoid tissue development resulting in cachexia and premature death. [source] Involutions resulting from annual freeze,thaw cycles: a laboratory simulation based on observations in northeastern JapanPERMAFROST AND PERIGLACIAL PROCESSES, Issue 4 2007Yoshiko Ogino Abstract A pilot laboratory experiment using a reversed two-layer soil model simulated small-scale involutions formed in a seasonal frost environment during the last glacial period. At the modelled site, the interface between the upper aeolian sandy loam and the lower volcanic pumice constitutes small-scale involutions that display upward-extending tapered projections and downward-extending round hollows. Two scale-reduced laboratory models were subjected to three accelerated annual freeze,thaw cycles with monitoring of frost heave, soil temperature, moisture and pressure. Ice segregation near the layer interface induces upheaving of coarse pumice grains on freezing and earlier settlement of mobilised loam on thawing, resulting in deformation of the interface. A reconstructed 3-D interface displays mounds and depressions with a diameter of 15,20,cm and a height increasing with freeze, thaw alternations. The experimental results imply that the repetition of differential heave and soft-loam settlement promotes decimetre-scale involutions in near-saturated soils subject to deep seasonal frost penetration. Copyright © 2007 John Wiley & Sons, Ltd. [source] Hemangiomas: Evaluation and TreatmentDERMATOLOGIC SURGERY, Issue 5 2001Scott M. Dinehart MD Background. Hemangiomas are common skin tumors of infancy that have undergone recent changes in nomenclature, methods of evaluation, and treatment. Objective. To review the nomenclature, epidemiology, evaluation, and treatment of common hemangiomas. Methods. A literature search was conducted utilizing MEDLINE and the Cochrane library databases. Text search words used were "hemangioma" and "infancy." The clinical experience of the authors was also used to formulate the review. Results. There have been many advances in nomenclature and therapeutic options for children with hemangiomas. Hemangiomas are proliferative tumors of infancy that should be distinguished from structural malformations, such as port-wine stains and lymphangiomas. Conclusion. Natural involution remains a viable treatment option for the majority of patients with uncomplicated hemangiomas. Excisional surgery, laser, and pharmacologic remedies are indicated for a subset of complicated hemangioma patients. [source] Changes in the cytologic distribution of heparin/heparan sulfate interacting protein/ribosomal protein L29 (HIP/RPL29) during in vivo and in vitro mouse mammary epithelial cell expression and differentiationDEVELOPMENTAL DYNAMICS, Issue 1 2002Catherine B. Kirn-Safran Abstract HIP/RPL29 is a small, highly basic, heparin/heparan sulfate interacting protein identical to ribosomal protein L29 and present in most adult epithelia. In the present study, we show that mouse HIP/RPL29 is ubiquitously present in adult mammary epithelia and is significantly increased during pregnancy and lactation. We observed for the first time that HIP/RPL29 intracellular expression and distribution varies, depending on the growth/differentiation state of the luminal epithelium. HIP/RPL29 was detected at low levels in mammary glands of virgin animals, increased markedly during lactation, and was lost again during involution. HIP/RPL29, preferentially found in the expanded cytoplasm of mature epithelial cells secreting milk, is present also in the nucleus of proliferating and differentiating ductal and alveolar elements. We used COMMA-D cells as an in vitro model for mammary-specific differentiation and examined similar intracellular redistribution of HIP/RPL29 associated with functional differentiation. However, no changes in HIP/RPL29 expression levels were detected in response to lactogenic hormones. Finally, the cellular distribution of HIP/RPL29 in both nuclear and cytoplasmic compartments was confirmed by transfecting a normal mammary epithelial cell line, NMuMG, with a fusion protein of HIP/RPL29 and EGFP. Collectively, these data support the idea that HIP/RPL29 plays more than one role during adult mammary gland development. © 2001 Wiley-Liss, Inc. [source] Cortical radial glial cells in human fetuses: Depth-correlated transformation into astrocytesDEVELOPMENTAL NEUROBIOLOGY, Issue 3 2003Leonardo C. deAzevedo Abstract In the human brain, the transformation of radial glial cells (RGC) into astrocytes has been studied only rarely. In this work, we were interested in studying the morphologic aspects underlying this transformation during the fetal/perinatal period, particularly emphasizing the region-specific glial fiber anatomy in the medial cortex. We have used carbocyanine dyes (DiI/DiA) to identify the RGC transitional forms and glial fiber morphology. Immunocytochemical markers such as vimentin and glial fibrillary acidic protein (GFAP) were also employed to label the radial cells of glial lineage and to reveal the early pattern of astrocyte distribution. Neuronal markers such as neuronal-specific nuclear protein (NeuN) and microtubule-associated protein (MAP-2) were employed to discern whether or not these radial cells could, in fact, be neurons or neuronal precursors. The main findings concern the beginning of RGC transformation showing loss of the ventricular fixation in most cases, followed by transitional figures and the appearance of mature astrocytes. In addition, diverse fiber morphology related to depth within the cortical mantle was clearly demonstrated. We concluded that during the fetal/perinatal period the cerebral cortex is undergoing the final stages of radial neuronal migration, followed by involution of RGC ventricular processes and transformation into astrocytes. None of the transitional or other radial glia were positive for neuronal markers. Furthermore, the differential morphology of RGC fibers according to depth suggests that factors may act locally in the subplate and could have a role in the process of cortical RGC transformation and astrocyte localization. The early pattern of astrocyte distribution is bilaminar, sparing the cortical plate. Few astrocytes (GFAP+) in the upper band could be found with radial processes at anytime. This suggests that astrocytes in the marginal zone could be derived from different precursors than those that differentiate from RGCs during this period. © 2003 Wiley Periodicals, Inc. J Neurobiol 55: 288,298, 2003 [source] Comparative gene expression in the heads of Drosophila melanogaster and Tribolium castaneum and the segmental affinity of the Drosophila hypopharyngeal lobesEVOLUTION AND DEVELOPMENT, Issue 1 2009Andrew D. Economou SUMMARY Drosophila melanogaster has long played an important role in debates surrounding insect and arthropod head segmentation. It is surprising, therefore, that one important feature of Drosophila head segmentation has remained controversial: namely the position of the boundary between the intercalary and mandibular segments. The Drosophila embryonic head has a pair of structures lying behind the stomodeum known as the hypopharyngeal lobes. Traditionally they have been seen as part of the intercalary segment. More recent work looking at the position of the lobes relative to various marker genes has been somewhat equivocal: segment polarity gene expression has been used to argue for a mandibular affinity of these lobes, while the expression of the anterior-most hox gene labial (lab) has supported an intercalary affinity. We have addressed the question of the segmental affinity of the hypopharyngeal lobes by conducting a detailed comparison of gene expression patterns between Drosophila and the red flour beetle Tribolium castaneum, in which the intercalary segment is unambiguously marked out by lab. We demonstrate that there is a large degree of conservation in gene expression patterns between Drosophila and Tribolium, and this argues against an intercalary segment affinity for the hypopharyngeal lobes. The lobes appear to be largely mandibular in origin, although some gene expression attributed to them appears to be associated with the stomodeum. We propose that the difficulties in interpreting the Drosophila head result from a topological shift in the Drosophila embryonic head, associated with the derived process of head involution. [source] Saw palmetto herbal blend causes involution of the prostatic epithelium in men with symptomatic benign prostatic hyperplasiaFOCUS ON ALTERNATIVE AND COMPLEMENTARY THERAPIES AN EVIDENCE-BASED APPROACH, Issue 4 2000Article first published online: 14 JUN 2010 [source] On (orientifold of) type IIA on a compact Calabi-YauFORTSCHRITTE DER PHYSIK/PROGRESS OF PHYSICS, Issue 1 2004A. Misra Abstract We study the gauged sigma model and its mirror Landau-Ginsburg model corresponding to type IIA on the Fermat degree-24 hypersurface in WCP4[1,1,2,8,12] (whose blow-up gives the smooth CY3(3,243)) away from the orbifold singularities, and its orientifold by a freely-acting antiholomorphic involution. We derive the Picard-Fuchs equation obeyed by the period integral as defined in [1, 2], of the parent ,, = 2 type IIA theory of [3]. We obtain the Meijer's basis of solutions to the equation in the large and small complex structure limits (on the mirror Landau-Ginsburg side) of the abovementioned Calabi-Yau, and make some remarks about the monodromy properties associated based on [4], at the same and another MATHEMATICAlly interesting point. Based on a recently shown ,, = 1 four-dimensional triality [6] between Heterotic on the self-mirror Calabi-Yau CY3(11,11), M theory on and F -theory on an elliptically fibered CY4 with the base given by CP1 × Enriques surface, we first give a heuristic argument that there can be no superpotential generated in the orientifold of of CY3(3,243), and then explicitly verify the same using mirror symmetry formulation of [2] for the abovementioned hypersurface away from its orbifold singularities. We then discuss briefly the sigma model and the mirror Landau-Ginsburg model corresponding to the resolved Calabi-Yau as well. [source] Globalization's Alternatives: Competing or Complementary Perspectives?1GOVERNMENT AND OPPOSITION, Issue 1 2008John Glenn Recent writings on globalization have tended to argue that such economic interconnectedness is, in one way or another, geographically delimited. Three competing views appear in the literature, regionalization, triadization and the involutionist perspective. This article challenges the portrayal of these perspectives as competing conceptions and instead argues that each perspective furnishes us with a partial view of a larger process. In so doing, this paper revisits the involutionist perspective, arguing that, in relation to the developing countries' relative share of world trade and investment shares, the use of the term ,globalization' should be questioned. Rather, in relation to trade, involution is a more apt description. However, in terms of FDI, stasis better describes the contemporary international economy. The article then examines the trade and investment patterns within the triad, corroborating earlier findings that each leg of the triad is increasingly trading more with their neighbours than with each other, but that inter-triad FDI is indeed increasing. Three main factors are presented in order to explain the contemporary patterns of trade and investment associated with involution, regionalization and triadization: product differentiation, vertical specialization and the continuing concentration on primary product production in much of the developing world. [source] The aryl hydrocarbon receptor: a perspective on potential roles in the immune systemIMMUNOLOGY, Issue 3 2009Emily A. Stevens Summary The aryl hydrocarbon receptor (AHR) is a protein best known for its role in mediating toxicity. Over 30 years of research has uncovered additional roles for the AHR in xenobiotic metabolism and normal vascular development. Activation of the AHR has long been known to cause immunotoxicity, including thymic involution. Recent data suggesting a role for the AHR in regulatory T-cell (Treg) and T-helper 17 (Th17) cell development have only added to the excitement about this biology. In this review, we will attempt to illustrate what is currently known about AHR biology in the hope that data from fields as diverse as evolutionary biology and pharmacology will help elucidate the mechanism by which AHR modifies immune responses. We also will discuss the complexities of AHR pharmacology and genetics that may influence future studies of AHR in the immune system. [source] Immunosenescence: emerging challenges for an ageing populationIMMUNOLOGY, Issue 4 2007Danielle Aw Summary It is now becoming apparent that the immune system undergoes age-associated alterations, which accumulate to produce a progressive deterioration in the ability to respond to infections and to develop immunity after vaccination, both of which are associated with a higher mortality rate in the elderly. Immunosenescence, defined as the changes in the immune system associated with age, has been gathering interest in the scientific and health-care sectors alike. The rise in its recognition is both pertinent and timely given the increasing average age and the corresponding failure to increase healthy life expectancy. This review attempts to highlight the age-dependent defects in the innate and adaptive immune systems. While discussing the mechanisms that contribute to immunosenescence, with emphasis on the extrinsic factors, particular attention will be focused on thymic involution. Finally, we illuminate potential therapies that could be employed to help us live a longer, fuller and healthier life. [source] Stromal remodelling is required for progressive involution of the rat ventral prostate after castration: Identification of a matrix metalloproteinase-dependent apoptotic waveINTERNATIONAL JOURNAL OF ANDROLOGY, Issue 5 2010A. Bruni-Cardoso Summary Prostate epithelial-cell apoptosis occurs in response to androgen deprivation. We have hypothesized that continued regression would require stromal changes. Studying apoptosis kinetics up to the 14th day after castration, we identified successive waves of apoptosis, with a prominent peak on day 11. This peak was associated with caspase-3 activity, nuclear translocation of apoptosis-inducing factor and clusterin expression. The apoptosis peak on day 11 was preceded by increased MMP-2 and MMP-7 activation, and MMP-9 expression on days 9 and 10. Treatment with the matrix metalloproteinases inhibitors doxycyclin, hydrocortisone, or GM6001 caused significant reduction in the apoptosis rate on day 11. The present data demonstrate that prostatic epithelial-cell deletion at the 11th day after castration was induced by focal degradation of the extracellular matrix associated with stromal remodelling. [source] Synchronous and multiple transitional cell carcinoma of the bladder and urachal cystINTERNATIONAL JOURNAL OF UROLOGY, Issue 6 2008Vinka Maletic Abstract: Incomplete involution of the allantoic duct can result in different pathological forms of urachus which can give rise to inflammation or late malignant changes. Among urachal tumors, adenocarcinoma is most frequent, although other histological types can also be found. The synchronous presentation of a urachal transitional cell tumor, along with recurrent superficial bladder tumors has not been reported previously. We are reporting a 49-year-old male patient in whom transitional cell carcinoma of a urachal cyst was found with recurrent, multiple bladder tumors. The diagnosis of urachal cyst tumor was established according to ultrasonography and computed tomography. Most of the bladder tumors were resected transurethrally while open surgical excision of the urachal cyst with en bloc resection of the bladder dome was performed. Recurrent bladder tumors were afterwards treated with Bacillus Calmette Guerin (BCG) instillations. A year after surgery the patient has no signs of local recurrence or distant metastases of transitional cell carcinoma. [source] Estimation of number of follicles, volume of colloid and inner follicular surface area in the thyroid gland of ratsJOURNAL OF ANATOMY, Issue 2 2005M. L. Hartoft-Nielsen Abstract Volume is an important variable in assessing the growth and involution of the thyroid gland. The functional unit in the thyroid is the follicle, which consists of thyrocytes surrounding colloid. The size of a follicle depends on the number of cells and the amount of colloid. These are interchangeable and vary according to biological activity. Direct measurements of these variables provide information on structures involved in thyroid hormone synthesis, storage and secretion, and also on changes at the morphological and functional levels. Stereological methods are developed to obtain information on three-dimensional structures from two-dimensional sections and to achieve information on an entire organ by examining a minor part of it. Full-grown male Sprague,Dawley rats were used to develop a set of methods relying on unbiased stereological principles to determine the number of follicles, the total volume of colloid and the inner follicular surface area in the thyroid gland. The total volume of colloid was positively correlated (P < 0.021) with the number of follicles and the inner follicular surface area (P < 0.002) but not to the mean volume of colloid in each follicle. Thus under physiological conditions an increase in the total volume of colloid is associated with an increased number of follicles with a constant size distribution rather than a larger volume of colloid in each follicle. This implies that under physiological conditions there is equilibrium in the size distribution of the volume of colloid in each follicle. [source] Phagocytic capacity of leucocytes in sheep mammary secretions following weaningJOURNAL OF ANATOMY, Issue 5 2002Liliana Tatarczuch Abstract Lactating animals are particularly susceptible to mastitis during the early stages of mammary gland involution following weaning. In this study we compared the phagocytic capacity of cells collected from sheep mammary secretions at different stages of involution. The ability of neutrophils and macrophages to ingest latex beads in an in vitro phagocytosis assay was found to be dependent on how heavily the phagocytes were loaded with milk constituents. There was a decline in the phagocytic capacity of neutrophils from 1 to 2 days after weaning, while macrophages collected from fully involuted glands were more effective phagocytes compared with earlier stages (7,15 days) of involution. In addition, dendritic cells present in fully involuted mammary gland secretions (30 days after weaning) were highly phagocytic. These studies demonstrate that neutrophils and macrophages in sheep mammary secretions at early stages of involution are incapacitated, and as such may compromise the immune status of the mammary gland. [source] Adrenergic-Cholinergic Interaction that Modulates Repolarization in the Atrium is Altered with AgingJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 4 2002EUGENE A. SOSUNOV Ph.D. Autonomic Modulation of Atrial Repolarization.Introduction: Aging is associated with involution of both limbs of the autonomic nervous system, and the prejunctional and postjunctional effects of adrenergic and cholinergic stimulation are altered with senescence. Hence, postjunctional age-related changes in adrenergic-cholinergic interaction are a likely occurrence and may contribute to an altered substrate for arrhythmias. Methods and Results: Microelectrode techniques were used to record action potentials from epicardial slices of Bachmann's bundles of dogs aged 3 to 5 years (adult) and 8 to 12 years (old) in the absence or presence of acetylcholine and isoproterenol (separately and in combination). In control, action potential duration to 90% repolarization (APD) was longer in old atria. Acetylcholine (10,8 to 10,5 mol/L) in a concentration-dependent manner hyperpolarized and shortened APD in both tissues, with more prominent effects in the old. The effects of isoproterenol (10,9 to 10,6 mol/L) to elevate the plateau and shorten APD were about the same in both adult and old tissues. In adults, low concentrations of isoproterenol (10,9 and 10,8 mol/L) significantly prolonged APD, which had been first shortened by acetylcholine. This effect of isoproterenol was decreased in old atrial tissue, resulting in shorter APD in old than adult atria in the combined presence of beta-adrenergic and muscarinic agonists. Conclusion: In adult Bachmann's bundle, beta-adrenergic stimulation effectively operates as a "brake" to decrease the extent of cholinergic-induced APD shortening. The action of beta-adrenergic stimulation to antagonize acetylcholine-induced acceleration of repolarization declines with age, which may contribute to an altered arrhythmogenic substrate. [source] Urachal remnants in asymptomatic children: Gray-scale and color Doppler sonographic findingsJOURNAL OF CLINICAL ULTRASOUND, Issue 4 2001Süha Süreyya Özbek MD Abstract Purpose We undertook this study to evaluate the frequency of visualization and the sonographic appearances of urachal remnants (URs) in asymptomatic children. Methods One hundred eighty-two children without any urachus-related symptoms underwent sonography of the prevesical region and urinary bladder with high-frequency transducers. Results A UR was visualized in 180 (99%) of the children. The URs had a mean length ± standard deviation of 13 ± 5 mm. Most of the URs were ovoid, and most demonstrated a moderate protrusion into the bladder cavity. The URs with a central echogenic area were larger than those without central echogenicity. In 36 (61%) of the 59 URs that were evaluated with color Doppler sonography, vascular signals were demonstrated within the lesion. The URs with internal vascular signals were significantly larger than those without internal vascular signals. Conclusions The gray-scale and color Doppler sonographic characteristics of URs seem to be related to their size and their degree of involution rather than to the age of the child. We think that URs are present in almost all children. URs should be considered normal findings if they are asymptomatic and their length is not significantly greater than 22.5 mm, the 95th percentile in our study. © 2001 John Wiley & Sons, Inc. J Clin Ultrasound 29:218,222, 2001. [source] Thiazolidinedione treatment and constitutive-PPAR, activation induces ectopic adipogenesis and promotes age-related thymic involutionAGING CELL, Issue 4 2010Yun-Hee Youm Summary Age-related thymic involution is characterized by reduction in T cell production together with ectopic adipocyte development within the hematopoietic and thymic niches. Peroxisome proliferator-activated receptor gamma (PPAR,) is required for adipocyte development, glucose homeostasis and is a target for several insulin-sensitizing drugs. Our prior studies showed that age-related elevation of PPAR, expression in thymic stromal cells is associated with thymic involution. Here, using clinically relevant pharmacological and genetic manipulations in mouse models, we provide evidence that activation of PPAR, leads to reduction in thymopoiesis. Treatment of aged mice with antihyperglycemic PPAR,-ligand class of thiazolidinedione drug, rosiglitazone caused robust thymic expression of classical pro-adipogenic transcripts. Rosiglitazone reduced thymic cellularity, lowered the naïve T cell number and T cell receptor excision circles (TRECs) indicative of compromised thymopoiesis. To directly investigate whether PPAR, activation induces thymic involution, we created transgenic mice with constitutive-active PPAR, (CA-PPARg) fusion protein in cells of adipogenic lineage. Importantly, CA-PPAR, transgene was expressed in thymus and in fibroblast-specific protein-1/S100A4 (FSP1+) cells, a marker of secondary mesenchymal cells. The CAPPAR, fusion protein mimicked the liganded PPAR, receptor and the transgenic mice displayed increased ectopic thymic adipogenesis and reduced thymopoiesis. Furthermore, the reduction in thymopoiesis in CA-PPAR, mice was associated with higher bone marrow adiposity and lower hematopoietic stem cell progenitor pool. Consistent with lower thymic output, CAPPAR, transgenic mice had restricted T cell receptor repertoire diversity. Collectively, our data suggest that activation of PPAR, accelerates thymic aging and thymus-specific PPAR, antagonist may forestall age-related decline in T cell diversity. [source] Declining expression of a single epithelial cell-autonomous gene accelerates age-related thymic involutionAGING CELL, Issue 3 2010Liguang Sun Summary Age-related thymic involution may be triggered by gene expression changes in lymphohematopoietic and/or nonhematopoietic thymic epithelial cells (TECs). The role of epithelial cell-autonomous gene FoxN1 may be involved in the process, but it is still a puzzle because of the shortage of evidence from gradual loss-of-function and exogenous gain-of-function studies. Using our recently generated loxP -floxed- FoxN1(fx) mouse carrying the ubiquitous CreERT (uCreERT) transgene with a low dose of spontaneous activation, which causes gradual FoxN1 deletion with age, we found that the uCreERT -fx/fx mice showed an accelerated age-related thymic involution owing to progressive loss of FoxN1+ TECs. The thymic aging phenotypes were clearly observable as early as at 3,6 months of age, resembling the naturally aged (18,22-month-old) murine thymus. By intrathymically supplying aged wild-type mice with exogenous FoxN1-cDNA, thymic involution and defective peripheral CD4+ T-cell function could be partially rescued. The results support the notion that decline of a single epithelial cell-autonomous gene FoxN1 levels with age causes primary deterioration in TECs followed by impairment of the total postnatal thymic microenvironment, and potentially triggers age-related thymic involution in mice. [source] The enigma of increased non-cancer mortality after weight loss in healthy men who are overweight or obeseJOURNAL OF INTERNAL MEDICINE, Issue 1 2002P. M. NILSSON Abstract.,Nilsson PM, Nilsson J-A, Hedblad B, Berglund G, Lindgärde F. (University Hospital, Malmö, Sweden). The enigma of increased non-cancer mortality after weight loss in healthy men who are overweight or obese. J Intern Med 2002; 252: 70,78. Objective.,To study effects on non-cancer mortality of observational weight loss in middle-aged men stratified for body mass index (BMI), taking a wide range of possible confounders into account. Design.,Prospective, population based study. Setting.,Male population of Malmö, Sweden. Participants.,In all 5722 men were screened twice with a mean time interval of 6 years in Malmö, southern Sweden. They were classified according to BMI category at baseline (<21, 22,25, overweight: 26,30, and obesity: 30+ kg m,2) and weight change category until second screening (weight stable men defined as having a baseline BMI ± 0.1 kg m,2 year,1 at follow-up re-screening). Main outcome measures.,Non-cancer mortality calculated from national registers during 16 years of follow-up after the second screening. Data from the first year of follow-up were excluded to avoid bias by mortality caused by subclinical disease at re-screening. Results.,The relative risk (RR; 95% CI) for non-cancer mortality during follow-up was higher in men with decreasing BMI in all subgroups: RR 2.64 (1.46,4.71, baseline BMI <21 kg m,2), 1.39 (0.98,1.95, baseline BMI 22,25 kg m,2), and 1.71 (1.18,2.47, baseline BMI 26+ kg m,2), using BMI-stable men as reference group. Correspondingly, the non-cancer mortality was also higher in men with increasing BMI, but only in the obese group (baseline BMI 26+ kg m,2) with RR 1.86 (1.31,2.65). In a subanalysis, nonsmoking obese (30+ kg m,2) men with decreased BMI had an increased non-cancer mortality compared with BMI-stable obese men (Fischer's test: P=0.001). The mortality risk for nonsmoking overweight men who increased their BMI compared with BMI-stable men was also significant (P=0.006), but not in corresponding obese men (P=0.094). Conclusions.,Weight loss in self-reported healthy but overweight middle-aged men, without serious disease, is associated with an increased non-cancer mortality, which seems even more pronounced in obese, nonsmoking men, as compared with corresponding but weight-stable men. The explanation for these observational findings is still enigmatic but could hypothetically be because of premature ageing effects causing so-called weight loss of involution. [source] Metamorphosis of cinctoblastula larvae (Homoscleromorpha, porifera)JOURNAL OF MORPHOLOGY, Issue 6 2007Alexander V. Ereskovsky Abstract The metamorphosis of the cinctoblastula of Homoscleromorpha is studied in five species belonging to three genera. The different steps of metamorphosis are similar in all species. The metamorphosis occurs by the invagination and involution of either the anterior epithelium or the posterior epithelium of the larva. During metamorphosis, morphogenetic polymorphism was observed, which has an individual character and does not depend on either external or species specific factors. In the rhagon, the development of the aquiferous system occurs only by epithelial morphogenesis and subsequent differentiation of cells. Mesohylar cells derive from flagellated cells after ingression. The formation of pinacoderm and choanoderm occurs by the differentiation of the larval flagellated epithelium. This is possibly due to the conservation of cell junctions in the external surface of the larval flagellated cells and of the basement membrane in their internal surface. The main difference in homoscleromorph metamorphosis compared with Demospongiae is the persistence of the flagellated epithelium throughout this process and even in the adult since exo- and endopinacoderm remain flagellated. The antero-posterior axis of the larva corresponds to the baso-apical axis of the adult in Homoscleromorpha. J. Morphol., 2007. © 2007 Wiley-Liss, Inc. [source] Ultrastructure of testicular macrophages in aging miceJOURNAL OF MORPHOLOGY, Issue 1 2005Francesco Giannessi Abstract Testicular macrophages of aging mice were studied by TEM. Testicular macrophages retained with Leydig cells the close morphological relationships observed in the adult young animals, but digitations were not found. Lipofuscin granules like those of the Leydig cells from aging mice were observed in the cytoplasm. These organelles were generally absent in the testicular macrophages of young adult mice. Testicular macrophages did not display phagocytosis of the lipofuscin granules. In addition, the latter were not found in the intercellular spaces. These observations indicated that lipofuscin granules were formed, at least in a great part, within testicular macrophages as a consequence of metabolic changes occurring with age. Fine lamellar organization was seen in the lipofuscin granules of both Leydig cells and testicular macrophages. Frequently, lipofuscin granules originated from secondary lysosomes containing lipidic vacuoles only. Together with accumulation of the lipofuscin granules, changes of testicular macrophage fine morphology were observed. Endoplasmic reticulum and Golgi apparatus became poorly developed, and coated vesicles were rarely found. Fewer mitochondria were encountered, but their ultrastructure was not altered. These results suggest that in testicular macrophages lipofuscin accumulation is associated with a functional involution. J. Morphol. 263:39,46, 2005.© 2004 Wiley-Liss, Inc. [source] The Medial Amygdala Modulates Body Weight but not Neuroendocrine Responses to Chronic StressJOURNAL OF NEUROENDOCRINOLOGY, Issue 1 2010M. B. Solomon Stress pathologies such as depression and eating disorders (i.e. anorexia nervosa) are associated with amygdalar dysfunction, which are linked with hypothalamic-pituitary-adrenal axis (HPA) axis hyperactivity. The medial amygdaloid nucleus (MeA), a key output nucleus of the amygdaloid complex, promotes HPA axis activation to acute psychogenic stress and is in a prime position to mediate the deleterious effects of chronic stress on physiology and behaviour. The present study tests the hypothesis that the MeA is necessary for the development of maladaptive physiological changes caused by prolonged stress exposure. Male rats received bilateral ibotenate or sham lesions targeting the MeA and one half underwent 2 weeks of chronic variable stress (CVS) or served as home cage controls. Sixteen hours post CVS, all animals were exposed to an acute restraint challenge. CVS induced thymic involution, adrenal hypertrophy, and attenuated body weight gain and up-regulation of hypothalamic corticotrophin-releasing hormone mRNA expression. Consistent with previous literature, lesions of the MeA dampened stress-induced increases in corticosterone after 30 min of exposure to acute restraint stress. However, this effect was independent of CVS exposure, suggesting that the MeA may not be critical for modulating neuroendocrine responses after chronic HPA axis drive. Interestingly, lesion of the MeA modestly exaggerated the stress-induced attenuation of weight gain. Overall, the data obtained suggest that the MeA modulates the neuroendocrine responses to acute but not chronic stress. In addition, the data suggest that the MeA may be an important neural component for the control of body weight in the face of chronic stress. [source] Perinatal Influences of Melatonin on Testicular Development and Photoperiodic Memory in Siberian HamstersJOURNAL OF NEUROENDOCRINOLOGY, Issue 8 2005C. R. Tuthill Abstract We assessed the influence of perinatal melatonin on reproductive development and adult responsiveness to melatonin. Testicular growth in an intermediate day length (14 : 10 h light/dark cycle) was substantially reduced in Siberian hamsters gestated by pinealectomised compared to pineal-intact females; gonadal development was normalised in offspring of pinealectomised dams that were pinealectomised at 3,4 days of age. Hamsters deprived of melatonin only during gestation, or both pre- and postnatally, underwent testicular involution during treatment with melatonin in adulthood. Photoperiodic histories acquired prenatally did not endure as long as those acquired by adult hamsters. Hamsters first exposed to melatonin in adulthood were not more proficient in acquiring photoperiodic histories than were normal males. These findings indicate that pre- versus postnatal differences in melatonin signal duration determine rates of testicular development. Exposure to melatonin perinatally does not appear to organise the neuroendocrine substrate that mediates effects of day length and melatonin on the gonads of adult hamsters. [source] Abdominal hernias in pregnancyJOURNAL OF OBSTETRICS AND GYNAECOLOGY RESEARCH (ELECTRONIC), Issue 2 2009Goran Augustin Abstract A hernia is an area of weakness or complete disruption of the fibromuscular tissues of the body wall. In addition to the body wall, hernias can occur in the diaphragm, pelvic wall, perineum, pelvic floor, and internal abdominal viscera (hernias through omental or mesenteric defects, ligaments and folds). Surgical repair of different types of hernia is the most common general surgical procedure with more than 20 million hernioplasties performed each year. Abdominal wall hernias are not common during pregnancy. Hernias can be symptomless or have minimal symptoms, including slight discomfort or pain. Such hernias are not life-threatening and should be controlled on regular basis. After spontaneous delivery and uterine involution, they should be repaired on an elective basis. It is of utmost importance for a clinician to diagnose emergent situations, which include incarceration, strangulation and perforation caused by hernia because consultation with a surgeon and emergency operation are mandatory. There is still no consensus for irreducible hernia during pregnancy, but complications during pregnancy outweigh elective operation. Therefore, hernioplasty is recommended during pregnancy, especially in early gestation. [source] Thick Prescriptions: Toward an Interpretation of Pharmaceutical Sales PracticesMEDICAL ANTHROPOLOGY QUARTERLY, Issue 3 2004MICHAEL J. OLDANI Anthropologists of medicine and science are increasingly studying all aspects of pharmaceutical industry practices,from research and development to the marketing of prescription drugs. This article ethnographically explores one particular stage in the life cycle of pharmaceuticals: sales and marketing. Drawing on a range of sources,investigative journalism, medical ethics, and autoethnography,the author examines the day-to-day activities of pharmaceutical salespersons, or drug reps, during the 1990s. He describes in detail the pharmaceutical gift cycle, a three-way exchange network between doctors, salespersons, and patients and how this process of exchange is currently in a state of involution. This gift economy exists to generate prescriptions (scripts) and can mask and/or perpetuate risks and side effects for patients. With implications of pharmaceutical industry practices impacting everything from the personal-psychological to the global political economy, medical anthropologists can play a lead role in the emerging scholarly discourse concerned with critical pharmaceutical studies. [source] Age-dependent changes in the nervous and endocrine control of the thymusMICROSCOPY RESEARCH AND TECHNIQUE, Issue 2 2004Jonas Hannestad Abstract The immune system, especially the thymus, undergoes age-related modifications leading to structural and functional changes in the lymphoid organs and immunocompetent cells. Nevertheless, the consequences of thymic involution in the peripheral pool of T-cells are still a matter of controversy. The control of the thymic function is very complex and involves intrathymic signals, the autonomic nervous system, and the endocrine system. Both thymocytes and thymic stromal cells express receptors for a wide range of hormones, as well as for neurotransmitters and neuropeptides, thus affecting thymocytes maturation. This review summarizes the age-dependent variations in the extrathymic components of the thymic microenvironment, i.e., vegetative nerves and hormones, and the possible effects of those changes in the immune function. Microsc. Res. Tech. 63:94,101, 2004. © 2004 Wiley-Liss, Inc. [source] Communities of complicity: Notes on state formation and local sociality in rural ChinaAMERICAN ETHNOLOGIST, Issue 3 2010DR. HANS STEINMÜLLER ABSTRACT In this article, I deal with the tension in rural China between vernacular practice in local sociality and official representations related to processes of state formation and with the ways in which this tension is revealed and concealed through gestures of embarrassment, irony, and cynicism. Such gestures point toward a space of intimate self-knowledge that I call a "community of complicity," a concept derived from Michael Herzfeld's outline of "cultural intimacy." I illustrate how such communities are constituted with examples involving Chinese geomancy (fengshui), funerary rituals, and corruption. I contrast this approach with arguments made about "state involution" in China. [source] Revision of the genus Acrochordiceras Hyatt, 1877 (Ammonoidea, Middle Triassic): morphology, biometry, biostratigraphy and intra-specific variabilityPALAEONTOLOGY, Issue 5 2010CLAUDE MONNET Abstract:, The family Acrochordiceratidae Arthaber, 1911 ranges in age from latest Spathian to the middle/late Anisian boundary, and it represents a major component of ammonoid faunas during that time. The middle Anisian genus Acrochordiceras Hyatt, 1877 is the most widespread taxon of the family and occurs abundantly worldwide within the low paleolatitude belt. However, there is a profusion of species names available for Acrochordiceras. This excessive diversity at the species level essentially results from the fact that sufficiently large samples were not available, thus leading to a typological approach to its taxonomy. Based on new extensive collections obtained from the Anisian (Middle Triassic) Fossil Hill Member (Star Peak Group, north-west Nevada) for which a high resolution biostratigraphic frame is available, the taxonomy and biostratigraphy of the genus Acrochordiceras Hyatt, 1877 is herein revised with respect to its intra-specific variation. Morphological and biometric studies (c. 550 bedrock-controlled specimens were measured) show that only one species occurs in each stratigraphic level. Continuous ranges of intra-specific variation of studied specimens enable us to synonymize Haydenites Diener, 1907, Silesiacrochordiceras Diener, 1916 and Epacrochordiceras Spath, 1934 with Acrochordiceras Hyatt, 1877. Three stratigraphically successive species are herein recognized in the low paleolatitude middle Anisian faunas from Nevada: A. hatschekii (Diener, 1907), A. hyatti Meek, 1877 and A. carolinae Mojsisovics, 1882. Moreover, an assessment of intra-specific variation of the adult size range does not support recognition of a dimorphic pair (Acrochordiceras and Epacrochordiceras) as previously suggested by other workers (Epacrochordiceras is the compressed and weakly ornamented end-member variant of Acrochordiceras). The successive middle Anisian species of Acrochordiceras form an anagenetic lineage characterized by increasing involution, adult size and intra-specific variation. This taxonomic revision based on new bedrock-controlled collections is thus an important prerequisite before studying the evolution of the group. [source] | |||||||||||||||||||||||||||||||||||||