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31.
A simple chemosensory response in Drosophila and the isolation of acj mutants in which it is affected. 总被引:5,自引:2,他引:5 下载免费PDF全文
M McKenna P Monte S L Helfand C Woodard J Carlson 《Proceedings of the National Academy of Sciences of the United States of America》1989,86(20):8118-8122
Although the Drosophila visual system has been described extensively, little is known about its olfactory system. A major reason for this discrepancy has been the lack of simple, reliable means of measuring response to airborne chemicals. This paper describes a jump response elicited by exposing Drosophila to chemical vapors. This behavior provides the basis for a single-fly chemosensory assay. The behavior exhibits dose dependence and chemical specificity: it is stimulated by exposure to ethyl acetate, benzaldehyde, and propionic acid but not ethanol. Animals can respond repeatedly at short intervals to ethyl acetate and propionic acid. The response relies on the third antennal segments. To illustrate the use of this behavior in genetic analysis of chemosensory response, nine acj mutants defective in response are isolated (acj = abnormal chemosensory jump), and their responses to two chemicals are characterized. All of the acj mutants are normal in giant fiber system physiology, and two exhibit defects in visual system physiology. 相似文献
32.
A recalcitrant, erythematous, desquamating disorder associated with toxin-producing staphylococci in patients with AIDS. 总被引:3,自引:0,他引:3
L A Cone D R Woodard R G Byrd K Schulz S M Kopp P M Schlievert 《The Journal of infectious diseases》1992,165(4):638-643
Although staphylococcal infections are common in patients with AIDS, staphylococcal toxin-related disorders have rarely been described. Five cases of a staphylococcal toxin-associated syndrome characterized by prolonged erythema, extensive cutaneous desquamation, hypotension, tachycardia, and multiple organ involvement are described in patients with AIDS. These illnesses were recurrent and recalcitrant with a mean duration of 50 days. Toxic shock syndrome toxin-1-producing staphylococci were isolated from three and staphylococcal enterotoxins B and A from one patient each. Sources of organisms were blood, one patient, and soft tissues and nasal accessory sinuses, two patients each. Three of the five patients died of renal failure and central nervous system abnormalities. One survivor required intubation for respiratory failure. All individuals manifested a marked diminution of CD4+ cells. Other laboratory abnormalities included azotemia and prolongation of partial thromboplastin time. Oliguria occurred in three patients. Thus, this recalcitrant erythematous desquamative disorder appears to be a variant of staphylococcal toxic shock syndrome in certain subsets of immunocompromised individuals. 相似文献
33.
Arrhythmogenic Evidence for Epicardial Adipose Tissue: Heart Rate Variability and Turbulence are Influenced by Epicardial Fat Thickness 下载免费PDF全文
34.
Todd Woodard Sigurdur Sigurdsson John D. Gotal Alyssa A. Torjesen Lesley A. Inker Thor Aspelund Gudny Eiriksdottir Vilmundur Gudnason Tamara B. Harris Lenore J. Launer Andrew S. Levey Gary F. Mitchell 《Journal of the American Society of Nephrology : JASN》2015,26(5):1181-1187
Aortic stiffening, assessed by carotid-femoral pulse wave velocity, is associated with CKD. Transmission of excessive flow pulsatility into the low-impedance renal microvasculature may mediate this association. However, direct analyses of macrovascular–microvascular relations in the kidney are limited. Using arterial tonometry, iohexol clearance, and magnetic resonance imaging, we related arterial stiffness, GFR, urinary albumin excretion, and potential mediators, including renal artery pulsatility index, renal vascular resistance, and arterial volume in the cortex, in 367 older adults (ages 72–92 years) participating in the Age, Gene/Environment Susceptibility-Reykjavik Study. In a model adjusted for age, sex, heart rate, and body size, aortic stiffness was related to GFR (Slope of regression B=−2.28±0.85 ml/min per SD, P=0.008) but not urine albumin (P=0.09). After accounting for pulsatility index, the relation between aortic stiffness and GFR was no longer significant (P=0.10). Mediation analysis showed that 34% of the relation between aortic stiffness and GFR was mediated by pulsatility index (95% confidence interval of indirect effect, −1.35 to −0.29). An additional 20% or 36% of the relation was mediated by lower arterial volume in the cortex or higher renal vascular resistance, respectively, when offered as mediators downstream from higher pulsatility index (95% confidence interval of indirect effect including arterial volume in the cortex, −2.22 to −0.40; 95% confidence interval of indirect effect including renal vascular resistance, −2.51 to −0.76). These analyses provide the first evidence that aortic stiffness may contribute to lower GFR by transferring excessive flow pulsatility into the susceptible renal microvasculature, leading to dynamic constriction or vessel loss. 相似文献
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37.
Comparative evolutionary genetics of spontaneous mutations affecting fitness in rhabditid nematodes 下载免费PDF全文
Baer CF Shaw F Steding C Baumgartner M Hawkins A Houppert A Mason N Reed M Simonelic K Woodard W Lynch M 《Proceedings of the National Academy of Sciences of the United States of America》2005,102(16):5785-5790
Deleterious mutations are of fundamental importance to all aspects of organismal biology. Evolutionary geneticists have expended tremendous effort to estimate the genome-wide rate of mutation and the effects of new mutations on fitness, but the degree to which genomic mutational properties vary within and between taxa is largely unknown, particularly in multicellular organisms. Beginning with two highly inbred strains from each of three species in the nematode family Rhabditidae (Caenorhabditis briggsae, Caenorhabditis elegans, and Oscheius myriophila), we allowed mutations to accumulate in the relative absence of natural selection for 200 generations. We document significant variation in the rate of decay of fitness because of new mutations between strains and between species. Estimates of the per-generation mutational decay of fitness were very consistent within strains between assays 100 generations apart. Rate of mutational decay in fitness was positively associated with genomic mutation rate and negatively associated with average mutational effect. These results provide unambiguous experimental evidence for substantial variation in genome-wide properties of mutation both within and between species and reinforce conclusions from previous experiments that the cumulative effects on fitness of new mutations can differ markedly among related taxa. 相似文献
38.
Plasma levels of plasminogen activator inhibitor type-1 (PAI-1), beta- thromboglobulin (beta TG), and fibrinopeptide A (FPA) were followed over 24 hours in 30 patients treated with alteplase for acute myocardial infarction. Samples were taken at baseline (T Oh), after 90 minutes (under alteplase, no heparin, T 1.5h), after 120 minutes (under alteplase and heparin, T 2h), 30 minutes after thrombolytic therapy (T 3.5h), as well as 12 hours (T 12h) and 24 hours (T 24h) after baseline. PAI-1 antigen levels (55 +/- 9 ng/mL at T Oh, mean +/- SEM) decreased to 35 +/- 5 (T 1.5h) and 40 +/- 6 (T 2h) ng/mL under alteplase, before increasing to 84 +/- 22 (T 3.5h), 130 +/- 30 (T 12h), and 64 +/- 7 (T 24h) ng/mL after therapy, P less than .001. A high baseline PAI-1 activity (18 +/- 3 ng/mL) decreased to 2.0 +/- 0.4 (T 1.5h) and 1.7 +/- 0.2 (T 2h) under alteplase and increased to 32 +/- 5 (T 12h) and 19 +/- 3 (T 24h) ng/mL after therapy (P less than .0001). beta TG levels (339 +/- 105 ng/mL at T Oh) decreased to 203 +/- 48 (T 2h), 154 +/- 51 (T 3.5h), 187 +/- 40 (T 12h), and 142 +/- 32 (T 24h) ng/mL under heparin (P less than .01). FPA levels (34 +/- 9 ng/mL at T Oh) increased to 85 +/- 15 ng/mL under alteplase alone (T 1.5h) and normalized under heparin (11 +/- 4, 6 +/- 2, 4 +/- 2, and 3 +/- 1 ng/mL at T 2h, T 3.5h, T 12h, and T 24h, respectively). A high level of FPA at T 3.5h correlated with reocclusion (33 +/- 12 ng/mL, n = 4 v 2.9 +/- 0.5 ng/mL, n = 21, P less than .005). We conclude that plasma levels of PAI- 1 antigen as well as activity markedly increase after alteplase therapy of acute myocardial infarction. The high activity of PAI-1 and decreasing beta TG levels suggest that platelets do not contribute significantly to this phenomenon. The marked increase of FPA levels under recombinant tissue-type plasminogen activator alone and its normalization under heparin emphasize the important role of concomitant anticoagulation in controlling further intravasal fibrin generation under alteplase. 相似文献
39.
Mahmoud Salama M. Lambertini MS Christianson Y. Jayasinghe A. Anazodo M. De Vos F. Amant C. Stern L. Appiah T. L. Woodard R. A. Anderson L. M. Westphal R. E. Leach K. A. Rodriguez-Wallberg P. Patrizio Teresa K. Woodruff 《Journal of assisted reproduction and genetics》2022,39(2):505
PurposeAs a further step to elucidate the actual diverse spectrum of oncofertility practices for breast cancer around the globe, we present and discuss the comparisons of oncofertility practices for breast cancer in limited versus optimum resource settings based on data collected in the Repro-Can-OPEN Study Part I & II.MethodsWe surveyed 39 oncofertility centers including 14 in limited resource settings from Africa, Asia & Latin America (Repro-Can-OPEN Study Part I), and 25 in optimum resource settings from the United States, Europe, Australia and Japan (Repro-Can-OPEN Study Part II). Survey questions covered the availability of fertility preservation and restoration options offered to young female patients with breast cancer as well as the degree of utilization.ResultsIn the Repro-Can-OPEN Study Part I & II, responses for breast cancer and calculated oncofertility scores showed the following characteristics: (1) higher oncofertility scores in optimum resource settings than in limited resource settings especially for established options, (2) frequent utilization of egg freezing, embryo freezing, ovarian tissue freezing, GnRH analogs, and fractionation of chemo- and radiotherapy, (3) promising utilization of oocyte in vitro maturation (IVM), (4) rare utilization of neoadjuvant cytoprotective pharmacotherapy, artificial ovary, and stem cells reproductive technology as they are still in preclinical or early clinical research settings, (5) recognition that technical and ethical concerns should be considered when offering advanced and innovative oncofertility options.ConclusionsWe presented a plausible oncofertility best practice model to guide oncofertility teams in optimizing care for breast cancer patients in various resource settings. 相似文献
40.
Vessel wall-derived endothelial cells rapidly proliferate because they contain a complete hierarchy of endothelial progenitor cells 总被引:10,自引:2,他引:10 下载免费PDF全文
Endothelial progenitor cells (EPCs) can be isolated from adult peripheral and umbilical cord blood and expanded exponentially ex vivo. In contrast, human umbilical vein endothelial cells (HUVECs) or human aortic endothelial cells (HAECs) derived from vessel walls are widely considered to be differentiated, mature endothelial cells (ECs). However, similar to adult- and cord blood-derived EPCs, HUVECs and HAECs derived from vessel walls can be passaged for at least 40 population doublings in vitro. Based on this paradox, we tested whether EPCs reside in HUVECs or HAECs utilizing a novel single cell deposition assay that discriminates EPCs based on their proliferative and clonogenic potential. We demonstrate that a complete hierarchy of EPCs can be identified in HUVECs and HAECs derived from vessel walls and discriminated by their clonogenic and proliferative potential. This study provides evidence that a diversity of EPCs exists in human vessels and provides a conceptual framework for determining both the origin and function of EPCs in maintaining vessel integrity. 相似文献