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Wagner D, Tissot M, Gordon D. Task-related environment alters the cuticular hydrocarbon composition of harvester ants. J Chem Ecol 2001; 27:1805-19. [PMID: 11545372 DOI: 10.1023/a:1010408725464] [Citation(s) in RCA: 98] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Within a colony of harvester ants (Pogonomyrmex barbatus), workers in different task groups differ in the hydrocarbon composition of the cuticle. Foragers and patrollers, which spend extended periods of time outside the nest, have a higher proportion of saturated, unbranched hydrocarbons (n-alkanes) on the cuticle than nest maintenance workers, which spend only short periods of time outside the nest. We tested whether these task-related differences in ant cuticular chemistry arise from exposure to conditions outside the nest. Nest maintenance workers experiencing daily, short-term outside exposure developed a higher proportion of n-alkanes on the cuticle than workers kept inside the lab. Independent manipulations of ultraviolet radiation, relative humidity, and temperature revealed that only the combination of high temperature (ca. 38 degrees C) and low relative humidity (ca. 8%) increased the proportion of cuticular n-alkanes. The results indicate that warm dry conditions, such as those encountered when an ant leaves the nest, trigger changes in cuticular chemistry.
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Li JP, Chang TM, Wagner D, Chey WY. Pancreatic phospholipase A2 from the small intestine is a secretin-releasing factor in rats. Am J Physiol Gastrointest Liver Physiol 2001; 281:G526-32. [PMID: 11447033 DOI: 10.1152/ajpgi.2001.281.2.g526] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
A secretin-releasing activity exists in the upper small intestine and pancreatic juice in the rat and the dog. Group I pancreatic phospholipase A2 (PLA2) in canine pancreatic juice and porcine pancreatic PLA2 stimulate the release of secretin from both STC-1 cells and a secretin-producing cell (S cell)-enriched preparation isolated from rat duodenal mucosa. We investigated the distribution and release of pancreatic PLA2-like immunoreactivity in the gastrointestinal tract and the role of PLA2 on the release of secretin and pancreatic exocrine secretion in response to duodenal acidification in anesthetized rats. PLA2-like immunoreactivity was detected in the mucosa throughout the gastrointestinal tract. High concentrations of PLA2 were found in both the small intestine and the pancreas. Duodenal acidification significantly increased the release of PLA2 from the upper small intestine (385% over basal secretion). Intravenous infusion of an anti-PLA2 serum (anti-PLA2) dose-dependently inhibited the release of secretin and pancreatic exocrine secretion in response to duodenal acid perfusion. Preincubation of the concentrate of intestinal acid perfusate (10-fold) from donor rats with the anti-PLA2 significantly suppressed its stimulation of secretin release and pancreatic exocrine secretion in recipient rats. We conclude that pancreatic PLA2 also functions as a secretin-releasing factor in the small intestine that mediates acid-stimulated release of secretin in rats.
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Limia A, Sangari FJ, Wagner D, Bermudez LE. Characterization and expression of secA in Mycobacterium avium. FEMS Microbiol Lett 2001; 197:151-7. [PMID: 11313128 DOI: 10.1111/j.1574-6968.2001.tb10597.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Mycobacterium avium is both a pathogen that infects several hosts such as humans, pigs, and birds, as well as a microorganism that is encountered in environmental sources (soil and water). Protein secretion by the bacterium is likely to influence its ability to overcome adverse and competitive conditions both within or outside the host. Using a combination of cloning and information available in the databank, we characterized the secA gene from M. avium, encoding for a major preprotein translocase subunit associated with the secretion system of prokaryotics. In addition, we cloned the secA promoter sequence in a reporter construct upstream of a promoterless gfp. It was determined that the secA of M. avium shares large homology with the secA of Mycobacterium tuberculosis but not with secA of Mycobacterium leprae. secA expression was determined to be greater at logarithmic growth phase although it was also expressed at low levels during the stationary phase. secA expression was also observed when the bacteria were incubated in water as well as within human monocyte-derived macrophages and in conditions that are associated with biofilm formation. Future evaluation of the sec pathway in M. avium might provide important information about secreted proteins that are required for survival in different environments.
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Bermudez LE, Wagner D, Sosnowska D. Mechanisms of Mycobacterium avium pathogenesis. Arch Immunol Ther Exp (Warsz) 2001; 48:521-7. [PMID: 11197607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
Infections caused by Mycobacterium avium are common in AIDS patients and patients with chronic lung diseases. The bacterium can be acquired both through the intestinal route and respiratory route. M. avium is capable of invading mucosal epithelial cells and translocating across the mucosa. The bacterium can infect macrophages, interfering with several functions of the host cell. The host defense against M. avium is primarily dependent on CD4+ T lymphocytes and natural killer cells. Activated macrophages can inhibit or kill intracellular bacteria by mechanisms that are currently unknown, but M. avium can invade resting macrophages and suppress key aspects of their function by triggering the release of transforming growth factor beta and interleukin 10. Co-infection with HIV-1 appears to be mutually beneficial, with both organisms growing faster.
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Zhao S, White DG, Ge B, Ayers S, Friedman S, English L, Wagner D, Gaines S, Meng J. Identification and characterization of integron-mediated antibiotic resistance among Shiga toxin-producing Escherichia coli isolates. Appl Environ Microbiol 2001; 67:1558-64. [PMID: 11282605 PMCID: PMC92769 DOI: 10.1128/aem.67.4.1558-1564.2001] [Citation(s) in RCA: 167] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A total of 50 isolates of Shiga toxin-producing Escherichia coli (STEC), including 29 O157:H7 and 21 non-O157 STEC strains, were analyzed for antimicrobial susceptibilities and the presence of class 1 integrons. Seventy-eight (n = 39) percent of the isolates exhibited resistance to two or more antimicrobial classes. Multiple resistance to streptomycin, sulfamethoxazole, and tetracycline was most often observed. Class 1 integrons were identified among nine STEC isolates, including serotypes O157:H7, O111:H11, O111:H8, O111:NM, O103:H2, O45:H2, O26:H11, and O5:NM. The majority of the amplified integron fragments were 1 kb in size with the exception of one E. coli O111:H8 isolate which possessed a 2-kb amplicon. DNA sequence analysis revealed that the integrons identified within the O111:H11, O111:NM, O45:H2, and O26:H11 isolates contained the aadA gene encoding resistance to streptomycin and spectinomycin. Integrons identified among the O157:H7 and O103:H2 isolates also possessed a similar aadA gene. However, DNA sequencing revealed only 86 and 88% homology, respectively. The 2-kb integron of the E. coli O111:H8 isolate contained three genes, dfrXII, aadA2, and a gene of unknown function, orfF, which were 86, 100, and 100% homologous, respectively, to previously reported gene cassettes identified in integrons found in Citrobacter freundii and Klebsiella pneumoniae. Furthermore, integrons identified among the O157:H7 and O111:NM strains were transferable via conjugation to another strain of E. coli O157:H7 and to several strains of Hafnia alvei. To our knowledge, this is the first report of integrons and antibiotic resistance gene cassettes in STEC, in particular E. coli O157:H7.
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Xiang M, Gan L, Li D, Zhou L, Chen ZY, Wagner D, O'Malley BW, Klein W, Nathans J. Role of the Brn-3 family of POU-domain genes in the development of the auditory/vestibular, somatosensory, and visual systems. COLD SPRING HARBOR SYMPOSIA ON QUANTITATIVE BIOLOGY 2001; 62:325-36. [PMID: 9598366] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Shields JA, Carvalho C, Shields CL, Singh AD, Wagner D. Bilateral choroidal metastasis from adenoid cystic carcinoma of the submandibular gland. Retina 2001; 20:406-7. [PMID: 10950424 DOI: 10.1097/00006982-200004000-00018] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Sobotta G, Wagner D. Critical phenomena of random spin systems: a renormalisation group approach. ACTA ACUST UNITED AC 2001. [DOI: 10.1088/0022-3719/11/7/035] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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185
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Pandit UA, Collier PJ, Malviya S, Voepel-Lewis T, Wagner D, Siewert MJ. Oral transmucosal midazolam premedication for preschool children. Can J Anaesth 2001; 48:191-5. [PMID: 11220430 DOI: 10.1007/bf03019734] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
PURPOSE To evaluate the acceptance and effectiveness of 0.2 mg x kg(-1) of oral transmucosal midazolam as a premedicant in infants and preschool children. METHOD In a randomized, prospective double-blind placebo controlled study, 44 healthy children, between the ages of eight months to six years, presenting for elective surgery were divided in two groups. The medicated group received 0.2 mg x kg(-1) of injectable midazolam mixed with an equal volume of strawberry syrup and the placebo group received plain syrup 0.08 ml x kg(-1). Medications were placed on the anterosuperior aspect of the child's tongue in 3-5 aliquots of 0.2-0.4 ml. A blinded observer assessed the acceptance of the medication by willingness to open the mouth for the next aliquot and the efficacy of the medication was assessed by ease of separation from the parent. RESULTS Ninety-six percent of the children in the placebo group and 95% in the midazolam group willingly accepted the medication. Separation of children from parents was successful in 95% of the medicated children compared with 59% in the placebo group (P = 0.006). CONCLUSION Oral midazolam in thick strawberry syrup, administered in small aliquots via the oral transmucosal route was well accepted and proved to be an effective premedicant in infants and preschool children.
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Albertia S, Arnold A, Borie E, Dammertz G, Erckmann V, Garin P, Giguet E, Illy S, Le Cloarec G, Le Goff Y, Magne R, Michel G, Piosczyk B, Tran C, Tran M, Thumm M, Wagner D. European high-power CW gyrotron development for ECRH systems. FUSION ENGINEERING AND DESIGN 2001. [DOI: 10.1016/s0920-3796(00)00514-7] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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187
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Plaum B, Wagner D, Kasparek W, Thumm M. Optimization of oversized waveguide components using a genetic algorithm. FUSION ENGINEERING AND DESIGN 2001. [DOI: 10.1016/s0920-3796(00)00526-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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188
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Weiner R, Bockhorn H, Rosenthal R, Wagner D. A prospective randomized trial of different laparoscopic gastric banding techniques for morbid obesity. Surg Endosc 2001; 15:63-8. [PMID: 11178766 DOI: 10.1007/s004640000303] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
BACKGROUND Slippage of the stomach is the most common postoperative complication after laparoscopic adjustable silicone gastric banding (LASGB) for morbid obesity. Retrogastric placement (RGP) of the band through the lesser sac can cause posterior slippage Incomplete suturing often is responsible for anterior slippage. A randomized prospective study was constructed to determine whether laparoscopic esophagogastric placement (EGP) is associated with a lower incidence of postoperative slippage and pouch dilation than RGP. METHODS Morbid obese patients presenting for LASGB were randomized to undergo either an EGP (n = 50) or an RGP (n = 51). Patients were blinded to which procedure they underwent, and follow-up date were obtained by a blinded independent investigator. Standardized clinical and radiologic controls were used to assess pouch enlargement and slippage. RESULTS Operating time was similar for the two procedures (54.5 min for EGP vs 58 min for RGP). There was no significant difference in postoperative weight loss (34 kg after EGP vs 37 kg after RGP within 12 months), esophagus dilation, or postoperative quality of life. There were two postoperative slippages and one pouch dilation in the RGP group and no postoperative complication in the EGP group. CONCLUSIONS The placement of a LAP-BAND adjustable gastric banding system by the EGP technique is safe and results in a lower frequency of postoperative complications than its placement by the RGP technique. Clear anatomic landmarks are a benefit to education and to the learning curve for LASGB.
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Wagner J, Martin Cabrejas LM, Grossmith CE, Papageorgiou C, Senia F, Wagner D, France J, Nolan SP. Synthesis of macrolide analogues of sanglifehrin by RCM: unique reactivity of a ruthenium carbene complex bearing an imidazol-2-ylidene ligand. Ring-closing metathesis. J Org Chem 2000; 65:9255-60. [PMID: 11149884 DOI: 10.1021/jo001296u] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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190
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Leelawattana R, Ziambaras K, Roodman-Weiss J, Lyss C, Wagner D, Klug T, Armamento-Villareal R, Civitelli R. The oxidative metabolism of estradiol conditions postmenopausal bone density and bone loss. J Bone Miner Res 2000; 15:2513-20. [PMID: 11127217 DOI: 10.1359/jbmr.2000.15.12.2513] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Because lifelong exposure to estrogen is a strong determinant of bone mass, we asked whether metabolic conversion of estrogen to either inactive or active metabolites would reflect postmenopausal bone mineral density (BMD) and rate of bone loss. Biochemical markers of inactive estrogen metabolites, urinary 2-hydroxyestrogen (2OHE1) and 2-methoxyestrogen (2MeOE1), and active metabolites, urinary 16alpha-hydroxyestrone (16alphaOHE1), estradiol (E2), and estriol (E3), were determined in 71 untreated, healthy postmenopausal women (age, 47-59 years) followed prospectively for 1 year. Urinary 2MeOE1 was correlated negatively with baseline vertebral (anteroposterior [AP] projection, r = -0.23 andp < 0.05; lateral view, r = -0.27 and p < 0.05) and proximal femur bone density measured by dual-energy X-ray absorptiometry (DXA; total, r = -0.38 and p < 0.01; neck, r = -0.28 and p = 0.02; trochanter, r = -0.44 and p < 0.01). BMDs of women in the lowest quartile of urinary 2MeOE1 (< 15 ng/g) were significantly higher than those in the highest quartile at all skeletal sites (p < 0.05). Likewise, women in the lowest quartile of urinary 2OHE1/16alphaOHE1 ratio (< 1.6) did not experience bone loss after 1 year, in contrast to women in the higher quartiles. We propose that the rate of inactivation of estrogens through 2-hydroxylation may contribute to postmenopausal osteoporosis.
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Wagner D, Wohlfarth EP. The pressure dependence of the Curie temperature of heterogeneous ferromagnetic alloys. ACTA ACUST UNITED AC 2000. [DOI: 10.1088/0305-4608/11/11/023] [Citation(s) in RCA: 70] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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192
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Irsigler P, Wagner D, Dunstan DJ. On the application of the Meyer-Neldel rule to a-Si:H. ACTA ACUST UNITED AC 2000. [DOI: 10.1088/0022-3719/16/34/010] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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193
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Mohn P, Wagner D, Wohlfarth EP. Magnetoelastic anomalies due to spin fluctuations in weakly itinerant ferromagnetic systems. ACTA ACUST UNITED AC 2000. [DOI: 10.1088/0305-4608/17/1/003] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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194
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Conforti L, Tarlton A, Mack TG, Mi W, Buckmaster EA, Wagner D, Perry VH, Coleman MP. A Ufd2/D4Cole1e chimeric protein and overexpression of Rbp7 in the slow Wallerian degeneration (WldS) mouse. Proc Natl Acad Sci U S A 2000; 97:11377-82. [PMID: 11027338 PMCID: PMC17208 DOI: 10.1073/pnas.97.21.11377] [Citation(s) in RCA: 212] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Exons of three genes were identified within the 85-kilobase tandem triplication unit of the slow Wallerian degeneration mutant mouse, C57BL/Wld(S). Ubiquitin fusion degradation protein 2 (Ufd2) and a previously undescribed gene, D4Cole1e, span the proximal and distal boundaries of the repeat unit, respectively. They have the same chromosomal orientation and form a chimeric gene when brought together at the boundaries between adjacent repeat units in Wld(S). The chimeric mRNA is abundantly expressed in the nervous system and encodes an in-frame fusion protein consisting of the N-terminal 70 amino acids of Ufd2, the C-terminal 302 amino acids of D4Cole1e, and an aspartic acid formed at the junction. Antisera raised against synthetic peptides detect the expected 43-kDa protein specifically in Wld(S) brain. This expression pattern, together with the previously established role of ubiquitination in axon degeneration, makes the chimeric gene a promising candidate for Wld. The third gene altered by the triplication, Rbp7, is a novel member of the cellular retinoid-binding protein family and is highly expressed in white adipose tissue and mammary gland. The whole gene lies within the repeat unit leading to overexpression of the normal transcript in Wld(S) mice. However, it is undetectable on Northern blots of Wld(S) brain and seems unlikely to be the Wld gene. These data reveal both a candidate gene for Wld and the potential of the Wld(S) mutant for studies of ubiquitin and retinoid metabolism.
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Weiner R, Wagner D, Blanco-Engert R, Bockhorn H. [A new technique for laparoscopic placement of the adjustable gastric band (LAP-band) for preventing slippage]. Chirurg 2000; 71:1243-50. [PMID: 11077586 DOI: 10.1007/s001040051210] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
BACKGROUND Slippage (SP) of the stomach is the most common postoperative complication after laparoscopic adjustable silicone gastric banding (LAS-GB) for morbid obesity. METHODS AND PATIENTS A randomized prospective study was constructed in order to determine whether laparoscopic placement behind the cardia (RKP) is associated with a lower incidence of postoperative SP and pouch dilation than after a retrogastric placement (RGP) of the LAP band using a common technique. Morbidly obese patients presenting for LASGB were randomized to undergo either an RKP (n = 50) or an RGP (n = 51). RESULTS There were three postoperative SP and three pouch dilations in the RGP group versus no postoperative complication in the RKP group. CONCLUSIONS The placement of LAP band by the RKP technique is safe and followed by a lower frequency of postoperative complications than with the RGP technique. Clear anatomical landmarks are a benefit to the education and learning curve of LASGB.
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Simmons DL, Wagner D, Westover K. Nonsteroidal anti-inflammatory drugs, acetaminophen, cyclooxygenase 2, and fever. Clin Infect Dis 2000; 31 Suppl 5:S211-8. [PMID: 11113025 DOI: 10.1086/317517] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Nonsteroidal anti-inflammatory drugs (NSAIDs) are frequently used antipyretic agents that most probably exert their antifever effect by inhibiting cyclooxygenase (COX)-2. Thus, COX-2-selective drugs or null mutation of the COX-2 gene reduce or prevent fever. Acetaminophen is antipyretic and analgesic, as are NSAIDs, but it lacks the anti-inflammatory and anticoagulatory properties of these drugs. This has led to the speculation that a COX variant exists that is inhibitable by acetaminophen. An acetaminophen-inhibitable enzyme is inducible in the mouse J774.2 monocyte cell line. Induction of acetaminophen-inhibitable prostaglandin E(2) synthesis parallels induction of COX-2. Thus, inhibition of pharmacologically distinct COX-2 enzyme activity by acetaminophen may be the mechanism of action of this important antipyretic drug.
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Brody S, Wagner D, Heinrichs M, James A, Hellhammer D, Ehlert U. Social desirability scores are associated with higher morning cortisol levels in firefighters. J Psychosom Res 2000; 49:227-8. [PMID: 11119778 DOI: 10.1016/s0022-3999(00)00169-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
OBJECTIVE To examine the association of social desirability (SD) responding ("defensiveness") and cortisol levels. METHODS Marlowe-Crowne SD scores and morning salivary cortisol were measured in firefighters. RESULTS SD scores were associated with higher cortisol levels (r=.28) in 60 firefighters under age 45, but not in 25 older firefighters (or the combined sample). CONCLUSION The results are consistent not only with SD scores being an indicator of coarctation of experience as a coping mechanism, but also (at least for younger persons) perhaps a risk factor for the psychobiological dysfunctions associated with chronic elevations of cortisol.
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Schneider G, Seidel R, Uder M, Wagner D, Weinmann HJ, Kramann B. In vivo microscopic evaluation of the microvascular behavior of FITC-labeled macromolecular MR contrast agents in the hamster skinfold chamber. Invest Radiol 2000; 35:564-70. [PMID: 10982002 DOI: 10.1097/00004424-200009000-00008] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
RATIONALE AND OBJECTIVES The extravasation properties of two macromolecular MR imaging contrast media (CM) in relation to structural differences of the terminal vascular bed were investigated to determine whether differentiation between normal (physiological) and tumor (pathological) tissue can be achieved by means of extravasation characteristics. METHODS Gd-DTPA-polylysine (50 kD, CM1) and Gd-DOTA cascade polymer (Gadomer 17; 20 kD, CM2) were labeled with fluorescein isothiocyanate (FITC) to enable in vivo fluorescence microscopy of the microcirculation. After implantation of a dorsal skinfold chamber and 7 days (range, 6-8) after induction of an amelanotic melanoma (A-Mel-3), 14 male hamsters weighing 85 g (range, 70-95 g) received 200 micromol/kg of CM1 by intravenous injection into the jugular vein. CM2 was similarly investigated after an interval of 24 hours. Fluorescence microscopy was performed in areas of subcutaneous tissue, striated muscle, and tumor tissue. Microscopic images were registered by a charge-coupled-device video camera and transferred to a video system. Distribution intensities of CM were evaluated on a digitally based measurement system. A control investigation was performed with FITC-dextran (150 kD). RESULTS Gd-DTPA-polylysine showed no extravasation into physiological tissue for the first 10 minutes after injection. After this period, however, the first signs of leakage became apparent. Gd-DOTA cascade polymer was extravasated after 5 minutes into the tumor-free tissue. In tumor capillaries, Gd-DTPA-polylysine could be detected in the extravasal space as well as in physiological tissue after 15 minutes. After injection of Gd-DOTA cascade polymer, direct leakage from tumor capillaries was observed, with a contrast maximum between tumor and surrounding tissue occurring 3 to 5 minutes after CM injection. Good delineation of tumor vascularization from striated muscle and subcutaneous tissue was achieved. CONCLUSIONS The CM studied showed different microvascular permeation properties. Faster leakage of Gd-DOTA cascade polymer was observed in areas with neoplastic tumor vessels, whereas extravasation in physiological tissue was detected after a period of 5 minutes. Gd-DTPA-polylysine demonstrated nonspecific leakage at later time points.
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May A, Wagner D, Langenbeck U, Weber A. [Family study of patients with aspirin intolerance and rhinosinusitis]. HNO 2000; 48:650-4. [PMID: 11056852 DOI: 10.1007/s001060050634] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
The high prevalence of aspirin intolerance in asthmatics and patients with nasal polyps as well as reports of familial clustering suggest a genetic disposition of this disease. Our study aimed at obtaining further evidence of hereditary factors in this disease. We included 33 unselected patients from 28 families with aspirin intolerance and rhinosinusitis in this study. Controls were recruited from individuals treated in our ENT clinic for diseases other than aspirin intolerance (n = 52). A questionnaire focused on family histories as well as reports on diseases of the upper respiratory tract or allergies. ASS intolerance was verified either by bronchial or nasal provocation tests. We found cases of aspirin intolerance among parents, siblings, and children of ASS intolerant probands. The children of probands had nasal polyps and rhinosinusitis more often than the children of controls. We propose that ASS intolerance with nasal polyps and asthma represents a complex phenotype, with genetic and environmental factors contributing to its manifestation.
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Shiromani PJ, Basheer R, Thakkar J, Wagner D, Greco MA, Charness ME. Sleep and wakefulness in c-fos and fos B gene knockout mice. BRAIN RESEARCH. MOLECULAR BRAIN RESEARCH 2000; 80:75-87. [PMID: 11039731 DOI: 10.1016/s0169-328x(00)00123-6] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
G-protein coupled receptor (GPCR) stimulation has been implicated in the regulation of sleep. Upon stimulation of a GPCR an intracellular cascade involving second and third messengers is initiated. The latter include the fos-family of immediate early genes (IEGs). Although there is considerable evidence indicating that IEGs are expressed in response to sleep, the effects of their deletion on sleep is not known. The present study examined sleep-wakefulness in mice lacking the c-fos or fos B genes. Null c-fos mice compared to their wildtype (WT) and heterozygote (het) siblings had more wakefulness and less slow wave sleep (SWS); REM sleep was not affected. The null c-fos mice also had increased delta activity (0.3-4 Hz). In contrast, the null and heterozygote fos B mice had less REM sleep, but the time spent in SWS or wakefulness was not different from their wild-type (WT) siblings. In the null c-fos mice, the increased wakefulness and the reduction in SWS could not be due to a systemic alteration in temperature since the core temperature was similar in all mice. By demonstrating that these IEGs are involved in sleep, we suggest that the deletion of specific genes, even within a family of genes, can have a specific effect on sleep.
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