scholarly journals Immune challenge retards seasonal reproductive regression in rodents: evidence for terminal investment

2006 ◽  
Vol 2 (3) ◽  
pp. 393-396 ◽  
Author(s):  
Zachary M Weil ◽  
Lynn B Martin ◽  
Joanna L Workman ◽  
Randy J Nelson
Keyword(s):  
Small Mammals ◽  
Environmental Conditions ◽  
Reproductive Function ◽  
Gram Negative Bacteria ◽  
Growth And Survival ◽  
Siberian Hamsters ◽  
The Face ◽  
Probability Of Death ◽  
Seasonally Breeding ◽  
Survival Mechanisms

Animals must balance investments in different physiological activities to allow them to maximize fitness in the environments they inhabit. These adjustments among reproduction, growth and survival are mandated because of the competing high costs of each process. Seasonally breeding rodents generally bias their investments towards reproduction when environmental conditions are benign, but shift these investments towards processes that promote survival, including immune activity, when environmental conditions deteriorate. Because survival probability of non-tropical small mammals is generally low in winter, under certain circumstances, these animals may not allocate resources to survival mechanisms in an effort to produce as many offspring as possible in the face of increased probability of death. Such ‘terminal investments’ have been described in passerines, but there are few examples of such phenomena in small mammals. Here, we show that male Siberian hamsters ( Phodopus sungorus ) challenged with lipopolysaccharide (a component of gram-negative bacteria that activates the immune system) induced a small, but significant, retardation of seasonal regression of the reproductive system relative to saline-injected hamsters. This delayed reproductive regression likely reflects a strategy to maintain reproductive function when survival prospects are compromised by infection.

scholarly journals Nuclear CD40 interacts with c-Rel and enhances proliferation in aggressive B-cell lymphoma

Blood ◽  
2007 ◽  
Vol 110 (6) ◽  
pp. 2121-2127 ◽  
Author(s):  
Hai-Jun Zhou ◽  
Lan V. Pham ◽  
Archito T. Tamayo ◽  
Yen-Chiu Lin-Lee ◽  
Lingchen Fu ◽  
...  
Keyword(s):  
B Cells ◽  
B Cell ◽  
Target Genes ◽  
Cell Lymphoma ◽  
B Cell Lymphoma ◽  
Promoter Activation ◽  
Growth And Survival ◽  
Survival Mechanisms ◽  
Lymphoma Therapy ◽  
Receptor Family

Abstract CD40 is an integral plasma membrane–associated member of the TNF receptor family that has recently been shown to also reside in the nucleus of both normal B cells and large B-cell lymphoma (LBCL) cells. However, the physiological function of CD40 in the B-cell nucleus has not been examined. In this study, we demonstrate that nuclear CD40 interacts with the NF-κB protein c-Rel, but not p65, in LBCL cells. Nuclear CD40 forms complexes with c-Rel on the promoters of NF-κB target genes, CD154, BLyS/BAFF, and Bfl-1/A1, in various LBCL cell lines. Wild-type CD40, but not NLS-mutated CD40, further enhances c-Rel–mediated Blys promoter activation as well as proliferation in LBCL cells. Studies in normal B cells and LBCL patient cells further support a nuclear transcriptional function for CD40 and c-Rel. Cooperation between nuclear CD40 and c-Rel appears to be important in regulating cell growth and survival genes involved in lymphoma cell proliferation and survival mechanisms. Modulating the nuclear function of CD40 and c-Rel could reveal new mechanisms in LBCL pathophysiology and provide potential new targets for lymphoma therapy.

scholarly journals Supplementation of Underfed Twin-Bearing Ewes with Herbal Vitamins C and E: Impacts on Birth Weight, Postnatal Growth, and Pre-Weaning Survival of the Lambs

Animals ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 652
Author(s):  
Víctor H. Parraguez ◽  
Francisco Sales ◽  
Oscar A. Peralta ◽  
Eileen Narbona ◽  
Raúl Lira ◽  
...  
Keyword(s):  
Birth Weight ◽  
Environmental Conditions ◽  
Postnatal Growth ◽  
Vitamin Supplementation ◽  
Growth And Survival ◽  
Maternal Undernutrition ◽  
Nutritional Strategy ◽  
Total Antioxidant ◽  
Positive Effect ◽  
Natural Prairie

Twin-bearing pregnancies of sheep reared in harsh environmental conditions result in maternal undernutrition and feto-maternal oxidative stress, leading to intrauterine growth restriction (IUGR). We assessed the efficiency of supplementation with antioxidant herbal vitamins C and E alone or in combination with concentrate throughout gestation on pregnancy outcomes, pre-weaning growth, and survival of twin lambs from grazing ewes at the Magellan Steppe. Four groups (n = 30 each) of twin-bearing ewes received a base natural prairie (P) diet, supplemented with either herbal vitamins C 500 mg and E 350 IU per day (V) or concentrated food (S); groups were: P, P + V, P + S, and P + VS. Vitamins and concentrate were supplemented until parturition. At birth, lambs were weighed, and blood was drawn for total antioxidant capacity (TAC) evaluation. Lamb body weight (BW) and survival rate were evaluated at mid-lactation (60 days) and at weaning (120 days). Vitamin supplementation resulted in increased lamb birth weight and TAC, with a trend towards higher BW at weaning, while nutritional supplementation only had a positive effect on birth weight. Lamb survival was higher in both vitamin supplemented groups. In conclusion, supplementation with herbal vitamins C and E alone or in combination with concentrate food during pregnancy may constitute a good nutritional strategy for sheep reared in harsh environmental conditions.

scholarly journals Photoperiod Influences the Effects of Exercise and Food Restriction on an Antigen-Specific Immune Response in Siberian Hamsters

Endocrinology ◽  
2004 ◽  
Vol 145 (2) ◽  
pp. 556-564 ◽  
Author(s):  
Staci D. Bilbo ◽  
Randy J. Nelson
Keyword(s):  
Body Mass ◽  
Food Restriction ◽  
Severity Of Illness ◽  
Reproductive Function ◽  
Delayed Type Hypersensitivity ◽  
Siberian Hamsters ◽  
Trade Offs ◽  
Access To Food ◽  
Short Days ◽  
Activity Condition

Abstract Environmental conditions influence the onset and severity of illness and infection and may compromise survival. Energetically challenging conditions during winter may directly induce death through hypothermia, starvation, or shock. The ability to forecast and prepare for the arrival of challenging conditions associated with winter (e.g. low temperatures, decreased food) likely confers survival advantages. Siberian hamsters (Phodopus sungorus) stop reproduction and reduce body mass (∼25%) during short, winter-like day lengths, resulting in energetic savings. Hamsters also increase circulating glucocorticoids and lymphocytes (e.g. T cells, NK cells), and exhibit enhanced antigen-specific delayed-type-hypersensitivity (DTH) responses in the skin during short days (SDs). We tested the hypothesis that Siberian hamsters use SD lengths to signal the onset of winter to mediate the energetic trade-offs among body mass, reproductive function, and immune function. Long-day (LD; 16 h light, 8 h dark) and SD (8 h light, 16 h dark) hamsters were either food restricted (25%) or provided ad libitum (ad lib) food for 4 wk; half of all hamsters in each food condition had voluntary access to a running wheel, and half remained sedentary. SD hamsters enhanced DTH responses compared with LD hamsters under sedentary ad lib conditions. Exercise enhanced DTH in LD hamsters regardless of food intake. Furthermore, food-restriction did not significantly influence DTH in LD hamsters. In contrast, food-restriction suppressed DTH in SD hamsters regardless of activity condition, and exercise modestly enhanced DTH only in SD hamsters with ad lib access to food. In sum, moderate energetic deficiency suppressed DTH in SD (but not LD) hamsters, and this suggests that hamsters may have evolved to enhance immune responses during winter in preparation for increased metabolic stressors.

scholarly journals MT1 Melatonin Receptors Mediate Somatic, Behavioral, and Reproductive Neuroendocrine Responses to Photoperiod and Melatonin in Siberian Hamsters (Phodopus sungorus)

Endocrinology ◽  
2010 ◽  
Vol 151 (2) ◽  
pp. 714-721 ◽  
Author(s):  
Brian J. Prendergast
Keyword(s):  
Reproductive Function ◽  
Melatonin Receptors ◽  
Day Length ◽  
Phodopus Sungorus ◽  
Receptor Subtypes ◽  
Gonadotropin Secretion ◽  
Siberian Hamsters ◽  
The Central Nervous System ◽  
Necessary And Sufficient ◽  
And Behavior

Environmental day length drives nocturnal pineal melatonin secretion, which in turn generates or entrains seasonal cycles of physiology, reproduction, and behavior. In mammals, melatonin (MEL) binds to a number of receptor subtypes including high-affinity (MT1 and MT2) and low-affinity (MT3, nuclear orphan receptors) binding sites, which are distributed throughout the central nervous system and periphery. The MEL receptors that mediate photoperiodic reproductive and behavioral responses to MEL have not been identified in a reproductively photoperiodic species. Here I tested the hypothesis that MT1 receptors are necessary and sufficient to engage photoperiodic responses by challenging male Siberian hamsters (Phodopus sungorus), a species that does not express functional MT2 receptors, with ramelteon (RAM), a specific MT1/MT2 receptor agonist. In hamsters housed in a long-day photoperiod, late-afternoon RAM treatment inhibited gonadotropin secretion, induced gonadal regression, and suppressed food intake and body mass, mimicking effects of MEL. In addition, chronic (24 h/d) RAM infusions were sufficient to obscure endogenous MEL signaling, and these treatments attenuated gonadal regression in short days. Together, the outcomes indicate that signaling at the MT1 receptor is sufficient and necessary to mediate the effects of photoperiod-driven changes in MEL on behavior and reproductive function in a reproductively photoperiodic mammal.

scholarly journals Growth and Survival Mechanisms Associated with Perineural Invasion in Prostate Cancer

2004 ◽  
Vol 64 (17) ◽  
pp. 6082-6090 ◽  
Author(s):  
Gustavo E. Ayala ◽  
Hong Dai ◽  
Michael Ittmann ◽  
Rile Li ◽  
Michael Powell ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Perineural Invasion ◽  
Growth And Survival ◽  
Survival Mechanisms

scholarly journals The phenomenon of rosacea-rushes (theoretical aspects)

2021 ◽  
Vol 26 (2) ◽  
pp. 33-39
Author(s):  
V.A. Bocharov ◽  
V.V. Bocharova ◽  
M.M. Lebediuk ◽  
A.A.S. Sarayreh ◽  
L.V. Kuts
Keyword(s):  
Clinical Manifestations ◽  
Reproductive Function ◽  
Local Heat ◽  
Cellular Level ◽  
Reproductive Age ◽  
Theoretical Substantiation ◽  
Promising Area ◽  
The Face ◽  
Relationship Of ◽  
The Relationship

According to the decisions of international scientific forums, the problem of phenomenon of rosacea (acne rosacea), a common dermatosis with numerous unexplained aspects of etiopathogenesis is a promising area of modern medical research. The aim of the study was theoretical substantiation of the essential features of the mechanisms of occurrence, development and clinical manifestations of the first signs of rosacea in women of reproductive age. The use of a systematic analytical methodical approach to assess the data of clinical and laboratory examinations of women with rosacea, conducted in different regions of the world, allowed to establish the originality of such manifestations of dermatosis as the appearance of unexpected rushes to limited areas of the face, accompanied by local redness and local heat areas of the skin differring significantly from similar rushes in other diseases or syndromes (menopause, migraine, etc.). It is established that the peculiarity of the relationship of these clinical characteristics (from English: rush, ruddy, redness, rosacea, reproductive age of women, reaction) allows to indicate the first signs of dermatosis as a phenomenon inherent in this disease Rush-Ruddy-Rosacea-Reproduce-Reaction (abbreviated – «5-R»), the key pathophysiological target of which (as well as the disease as a whole) is a disorder of a set of hierarchically dependent mechanisms of the evolutionarily determined motivational need to ensure reproductive function in women (both at the cellular level and extracellular structures of the ovaries, and at different levels of subcortical formations and centers of the cortex of the cerebral hemispheres). The phenomenon of rosacea rush is closely related to other phenomena of this dermatosis – hypersensitivity of bradykinin receptors, actinic elastosis, development of post erythematous telangiectasia. The prospect of further research on the problem of rosacea is to study the relationship of disorders in the functional systems of molecules of signaling compounds of different classes (hormones, eicosanoids, neuropeptides, kinins, cytokines and others) in the pathogenesis of the disease.

scholarly journals Sunburn Protection by Sunscreen Sprays at Beach

2017 ◽  
Author(s):  
Hao Ou-Yang ◽  
Richard Bradley Rzendzian
Keyword(s):  
Environmental Conditions ◽  
Healthy Subjects ◽  
Human Subjects ◽  
Real Life ◽  
The Body ◽  
Single Center ◽  
Human Behaviors ◽  
Actual Usage ◽  
Neck Area ◽  
The Face

Background: The efficacy of sunscreen is evaluated by SPF values, which are quantitatively determined in laboratories on the backs of human subjects according to a standardized procedure. However, SPF cannot be directly translated to sunburn protection under real-life situations because actual efficacy depends on various factors related to human behaviors and environmental conditions. This study clinically evaluated the efficacy of two sunscreen sprays (SPF 30 and SPF 70) under natural sunlight exposure on healthy subjects at the beach. Methods: Twenty subjects were divided into two cells for the two sunscreen sprays (SPF 70 and SPF 30) in a single-center, actual usage test. The primary endpoint of the study was sunburn protection on the dorsal arms and the secondary endpoint was protection on the face and neck. Subjects stayed at the beach for 4 h after application of the sunscreens with normal beach activities. Subjects’ behavior at the beach, the amounts of sunscreen applied and reapplied, and environmental conditions were all recorded. Results: There was no significant sunburn for a majority of the subjects in either cell. However, neither sunscreen completely blocked the sunburn, especially for the face/neck area. We found that the SPF 70 sunscreen was more effective than the SPF 30 sunscreen. Conclusion: Modern sunscreen sprays, applied liberally, are effective in providing sunburn protection for the body in a beach setting.

scholarly journals Major Regularities of Transformation of the Small Mammal Ovaries in Unfavourable Environmental Conditions: Ecological and Morphological Aspects

2021 ◽  
Vol 10 (4) ◽  
pp. 28-35
Author(s):  
E. V. Blinova ◽  
N. N. Shevlyuk
Keyword(s):  
Small Mammals ◽  
Small Mammal ◽  
Environmental Conditions ◽  
Functional Organization ◽  
Common Shrew ◽  
Mammal Species ◽  
Wood Mice ◽  
Wide Range ◽  
Mole Vole ◽  
Cortical Substance

The aim of the study was to determine the patterns of structural and functional organization of the ovaries of female small mammals inhabiting technogenically altered ecosystems.Material and methods. We studied the ovaries of small mammal species belonging to the insectivore and rodent families (common shrew, field and pygmy wood mice, common and bank voles, mole vole, steppe pied) that live in anthropogenically altered ecosystems (zones of influence of ferrous and nonferrous metallurgy, as well as gas processing factory). The resulting material was processed using observational histological, histochemical, immunohistochemical and morphometric tests.Results. The results obtained demonstrated that in technogenically altered ecosystems the intensified reproduction results in a complex of morphofunctional reactive and adaptive changes in the ovaries of females of the studied species. The size of the ovaries was reduced; the area of the cortical substance was reduced. In the cortex, there was revealed a decrease in the number of follicles varying over a wide range - from a moderate decrease to their almost complete absence. There was found a decrease in the area of the vessels of the microvasculature; this was one of the major reasons for the increased follicular atresia. In follicles of various types, there was an increase in the proportion of cells expressing the proapoptotic protein P53. A decrease in the number of follicles resulted in the connective tissue overgrowth. The presence of cysts lined with epithelium of various heights was revealed in the cortex and medulla. Conclusion. The results obtained evidence that in technogenically altered ecosystems a decreased ovarian reserve is observed in the ovaries of female small mammals; it is associated with a more rapid depletion of the follicle reserve in the cortex due to both - intensification of reproduction and more rapid death of follicles in unfavourable environmental conditions.

scholarly journals Bacillus subtilis Modulates Its Usage of Biofilm-Bound Iron in Response to Environmental Iron Availability

2020 ◽  
Vol 86 (22) ◽  
Author(s):  
Adrien Rizzi ◽  
Julie Leroux ◽  
Vincent Charron-Lamoureux ◽  
Sébastien Roy ◽  
Pascale B. Beauregard ◽  
...  
Keyword(s):  
Bacillus Subtilis ◽  
Environmental Conditions ◽  
Life Forms ◽  
Local Source ◽  
Extracellular Electron Transfer ◽  
Gram Negative Bacteria ◽  
Iron Availability ◽  
Content Type ◽  
Fe Isotopes ◽  
Fe Homeostasis

ABSTRACT Iron (Fe) is one of the most important micronutrients for most life forms on earth. While abundant in soil, Fe bioavailability in oxic soil is very low. Under environmental conditions, bacteria need to acquire sufficient Fe to sustain growth while limiting the energy cost of siderophore synthesis. Biofilm formation might mitigate this Fe stress, since it was shown to accumulate Fe in certain Gram-negative bacteria and that this Fe could be mobilized for uptake. However, it is still unclear if, and to what extent, the amount of Fe accumulated in the biofilm can sustain growth and if the mobilization of this local Fe pool is modulated by the availability of environmental Fe (i.e., Fe outside the biofilm matrix). Here, we use a nondomesticated strain of the ubiquitous biofilm-forming soil bacterium Bacillus subtilis and stable Fe isotopes to precisely evaluate the origin of Fe during growth in the presence of tannic acid and hydroxides, used as proxies for different environmental conditions. We report that this B. subtilis strain can accumulate a large quantity of Fe in the biofilm, largely exceeding Fe associated with cells. We also report that only a fraction of biofilm-bound Fe is available for uptake in the absence of other sources of Fe in the vicinity of the biofilm. We observed that the availability of environmental Fe modulates the usage of this pool of biofilm-bound Fe. Finally, our data suggest that consumption of biofilm-bound Fe relates to the efficacy of B. subtilis to transport Fe from the environment to the biofilm, possibly through siderophores. IMPORTANCE Recent pieces of evidence suggest that Fe bound to the biofilm could assume at least two important functions, a local source of Fe for uptake and a support to extracellular metabolism, such as extracellular electron transfer. Our results show that B. subtilis can use biofilm-bound Fe for uptake only if it does not compromise Fe homeostasis of the biofilm, i.e., maintains a minimum Fe concentration in the biofilm for extracellular purposes. We propose a theoretical framework based on our results and recent literature to explain how B. subtilis manages biofilm-bound Fe and Fe uptake in response to environmental Fe availability. These results provide important insights into the management of biofilm-bound and environmental Fe by B. subtilis in response to Fe stress.

scholarly journals Stress Management in Cyst-Forming Free-Living Protists: Programmed Cell Death and/or Encystment

2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Naveed Ahmed Khan ◽  
Junaid Iqbal ◽  
Ruqaiyyah Siddiqui
Keyword(s):  
Cell Death ◽  
Programmed Cell Death ◽  
Stress Management ◽  
Environmental Conditions ◽  
Free Living ◽  
Cyst Form ◽  
The Face ◽  
A Cell ◽  
Cellular Machinery ◽  
Harsh Conditions

In the face of harsh conditions and given a choice, a cell may (i) undergo programmed cell death, (ii) transform into a cancer cell, or (iii) enclose itself into a cyst form. In metazoans, the available evidence suggests that cellular machinery exists only to execute or avoid programmed cell death, while the ability to form a cyst was either lost or never developed. For cyst-forming free-living protists, here we pose the question whether the ability to encyst was gained at the expense of the programmed cell death or both functions coexist to counter unfavorable environmental conditions with mutually exclusive phenotypes.

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