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21.
Nancy Ballard Lois Robley Darcy Barrett Danielle Fraser Inocencia Mendoza 《American journal of critical care》2006,15(1):86-94; quiz 95
BACKGROUND: Neuromuscular blocking agents used for therapeutic purposes, such as facilitating mechanical ventilation and relieving life-threatening agitation, paralyze patients but leave them fully conscious. Aggressive sedation or analgesia is necessary to reduce awareness, relieve fear, produce comfort, decrease anxiety, induce unconsciousness, and minimize possible complications such as posttraumatic stress syndrome. Little information is available on the extent to which patients experience awareness during therapeutic paralysis. OBJECTIVES: To determine and describe the remembered experiences of critical care patients who were given neuromuscular blocking agents and sedatives and/or analgesics to facilitate mechanical ventilation, improve hemodynamic stability, and improve oxygenation. METHODS: A phenomenological approach with in-depth interviews with 11 patients was used. Data were analyzed by using the constant comparative approach. RESULTS: A total of 4 themes and 3 subthemes were identified. The first theme was back and forth between reality and the unreal, between life and death; the subtheme was having weird dreams. The second theme was loss of control; the 2 subthemes were (1) fighting or being tied down and (2) being scared. The third theme was almost dying, and the fourth theme was feeling cared for. CONCLUSIONS: Patients can remember having both negative and positive experiences during neuromuscular blockade. Steps to improve the experiences of patients receiving neuromuscular blockers include improving assessment parameters, developing and using sedation/analgesia guidelines, and investing in quality improvement programs to provide assessment of awareness during therapeutic paralysis and follow-up and referral as necessary. Ways to decrease the use of neuromuscular blockers would also be useful. 相似文献
22.
Adenocarcinomas of the colon arise from adenomatous polyps. We hypothesized that sucrase-isomaltase (SI), a glycoprotein hydrolase, found in normal small intestine, fetal colon, and colon carcinomas is a marker associated with progression of adenomatous polyps with dysplasia to adenocarcinomas. To examine this hypothesis, we performed immunostaining using a polyclonal antihuman SI antibody in 32 adenomatous polyps with varying degrees of dysplasia. In addition, sucrase enzyme activity was determined in three sets of simultaneously harvested polyps, cancer, and adjacent normal mucosa from the same patient. All severely dysplastic polyps (6/6) exhibited SI staining. Most polyps (85%) with 3+ staining (i.e., greater than 10% of polyp positive for SI) had severe dysplasia, whereas those with mild dysplasia had either 1% to 5% staining or no staining in 95% of the cases. These data indicate that the extent of SI immunostaining in polyps correlates with the degree of dysplasia (p = 0.0001). Sucrase-isomaltase activity in the polyps was 18.1 +/- 1.8 mU/mg (mean +/- SD); in adjacent carcinoma SI activity was 29.1 +/- 1.8 mU/mg. Adjacent mucosa showed no activity in all cases. In summary, our results suggest that SI expression correlates with the progression of dysplastic adenomatous polyps to carcinoma. Sucrase-isomaltase expression may be useful as a clinical marker to improve our prognostic capabilities in patients with dysplastic lesions of the colon, that is, inflammatory bowel disease. 相似文献
23.
G W Daneker A M Mercurio L Guerra B Wolf R R Salem D J Bagli G D Steele 《Archives of surgery (Chicago, Ill. : 1960)》1987,122(12):1470-1474
We are studying the ability of colorectal carcinomas, which vary in degree of differentiation, to assemble a basement membrane and the relationship between differences in this ability and perturbations in laminin expression. For these studies, we are using human colorectal carcinoma cells grown both in vitro and in nude mice as well as tumors obtained at surgery. Immunoperoxidase staining of human tumors indicates that laminin is present in a defined basement membrane in moderately to well-differentiated tumors. This staining pattern is absent in poorly differentiated tumors. In these tumors, staining is discontinuous and sometimes observed intracellularly. The laminin synthesized by in vitro cells was immunoprecipitated and analyzed by acrylamide electrophoresis. Neither poorly nor well-differentiated carcinoma cells exhibit marked differences in the rate of synthesis of laminin. Differences are present in the rate at which newly synthesized laminin is secreted. These differences may result from alterations in posttranslational processing. Such alterations may contribute, along with other factors, to the inability of poorly differentiated tumors to make a basement membrane. 相似文献
24.
Allegria Kessous Pierre Colombies Martine Sudries Georges Bourrouillou Jacques Pris Danielle Clement 《Cancer Genetics and Cytogenetics》1980,2(4):335-337
This report describes a new case of chronic myeloid leukemia with an unusual Philadelphia chromosome translocation involving chromosomes No. 4,9, and 22; t(4,9,22) (q31;q34;q11). 相似文献
25.
Mounir Chennaoui Danielle Gomez-Marino Catherine Drogou Cyprien Bourrilhon Samuel Sautivet Charles Yannick Guezennec 《Revue canadienne de physiologie appliquée》2004,29(6):714-730
The aim of this study was to examine hormonal and metabolic changes in a group of 18 professional male cyclists ((.)VO(2)max 69.9 [95 % CI 64.9 to 74.9] mL x kg(-1) x min(-1) ) during two successive periods of adapted intensive training. The second training period included 4 days of cycling competition. Intensity was increased while volume was decreased in the second training. Anthropometric data were collected before and at the end of the two training periods. Venous blood samples were taken in a basal state before the two training sessions and after each training session. Serum concentrations of cortisol (C), testosterone (T), dehydroepiandrosterone sulfate (DHEAs), and catecholamines were determined as well as branched-chain amino acids (valine, leucine, isoleucine) (BCAA) and free fatty acids (FFAs). At the end of the two training periods, the subjects lost fat mass whereas mean body mass was unchanged. The T/C ratio was reduced transiently after the first training session (45.90 %), while DHEAs/C remained unchanged. T/C and DHEAs/C were significantly increased after the second training session compared to the first (48.40 and 97.18 %, respectively). Catecholamines and FFAs were unchanged. The significant increase in BCAA levels after the second training session was of note as it might constitute a "store shape" of amino acids in anticipation of future intense training loads. Based on the responses of testosterone, DHEAs, and cortisol, and on the training-induced increase in BCAA, there appeared to be hormonal and metabolic adaptation despite the inherent psychological stress of competition. 相似文献
26.
Chlamydiales are important intracellular bacterial pathogens, causing a wide variety of diseases in vertebrates, including humans. Besides the well-known species in the family Chlamydiaceae, new chlamydial organisms have recently been discovered, forming three new families: Parachlamydiaceae, Simkaniaceae and Waddliaceae. Parachlamydia acanthamoebae and Simkania negevensis are currently investigated as emerging human respiratory pathogens. Additional chlamydial lineages have been discovered by 16S rDNA-based molecular studies, and their implication in human infections is poorly known. By using a pan-chlamydia 16S rDNA PCR, we have searched for the presence of chlamydiae in 228 clinical samples that all previously had been shown to be PCR-negative for Chlamydophila pneumoniae: 170 respiratory samples, 45 atheromatic plaques and 13 peripheral blood mononuclear cell samples. Nine respiratory samples tested positive. Sequence analysis has allowed us to assign four sequences to Chlamydophila psittaci, three sequences to Chlamydophila felis, and two sequences to two novel phylotypes belonging to the Parachlamydiaceae. These latter sequences showed similarity values of more than 93% with each other and with the P. acanthamoebae sequence, thus belonging to novel, unrecognized species. In conclusion, this report showed that a variety of non-C. pneumoniae chlamydial respiratory infection is present in humans, and that new parachlamydiae distinct from P. acanthamoebae may be detected in human clinical samples. Future studies will be of interest in order to estimate the diversity of these novel chlamydiae in both clinical and environmental samples, as well as their possible clinical implication in human and animal infections. 相似文献
27.
Nina M. Griffiths Chehrazade Brick-Ghannam Sylvie Siaume-Perez Danielle Chabardès 《Pflügers Archiv : European journal of physiology》1993,422(6):577-584
The effects of calcitonin, vasoactive intestinal peptide (VIP), parathyroid hormone (PTH) and isoprenaline on intracellular cAMP accumulation were determined in the distal tubule (DCT) microdissected from collagenase-treated rabbit kidney. In DCTb (the initial bright portion) calcitonin (10 ng/ml) elicited a highly reproducible response 203.7±19.1 fmol cAMP mm–1 4 min–1 (SE, N=13) whereas VIP-induced cAMP accumulation was less and more variable from one experiment to another (1 M, 97.2±17.8 fmol mm–1 4 min–1, SE, N=12). When used in combination, these two agonists were non-additive, indicating stimulation of a single pool of cAMP in DCTb. In DCTg, (granular) which consists of at least two cell types, PTH (100 nM) elicited a marked, reproducible accumulation of cAMP (154.3±27.0 fmol mm–1 4 min–1; SE, N=5). Isoprenaline (1 M) and VIP (1 M) induced much smaller increases in cAMP levels 20.9±2.7 and 29.4±4.1 fmol mm–1 4 min–1 (SE, N=5) respectively, and, when used in combination, were non-additive, demonstrating that VIP and isoprenaline are active on the same cell type. In DCTb, prostaglandin E2 (PGE2) inhibited both calcitoninand VIP-stimulated cAMP accumulation (calcitonin 57.8±2.7% inhibition, SE, N=16; VIP, 80.6±2.1% inhibition, SE, N=5). The EC50 values for calcitonin were 1.21±0.33 ng/ml and 1.83±0.25 ng/ ml (SD, N=3) in the absence and presence of PGE2 (300 nM) respectively with an IC50 for PGE2 of 26.3±6.3 nM (SE, N=4). In contrast, no effects of PGE2 were seen in DCTg vis à vis PTH, isoprenaline or VIP. The percentage inhibition of calcitonin-stimulated cAMP accumulation by PGE2 was of the same order in the presence of isobutylmethylxanthine (an inhibitor of all types of phosphodiesterase), Ro 20-1724 (inhibitor of low-K
m cAMP-specific phosphodiesterase) or in the absence of inhibitor. Preincubation of DCTb with pertussis toxin for up to 8 h in different experimental conditions did not relieve the inhibition by PGE2. Protein kinase C activation by phorbol ester did not attenuate calcitonin responses. These data demonstrate that the inhibition by PGE2 of cAMP production is restricted to the initial portion (DCTb) of the distal convoluted tubule and is effective on both calcitonin and VIP responses. When tested in the presence of Ro 20-1724, ionomycin, A1-adenosine, 2-adrenergic and muscarinic agonists were without effect on calcitoninand PTH-stimulated cAMP accumulation in DCTb and DCTg respectively. 相似文献
28.
Danielle K. Bourque Inara Chacon Fonseca Andrea Staines Ronni Teitelbaum Michelle M. Axford Rebekah Jobling David Chiasson David Chitayat 《American journal of medical genetics. Part A》2019,179(7):1325-1329
Alveolar capillary dysplasia with misalignment of the pulmonary veins (ACDMPV) is a rare, autosomal dominant disorder of interstitial lung development, leading to pulmonary hypertension, and death in infancy. Associated features include malformations of the heart, gastrointestinal tract, and genitourinary system. ACDMPV is caused by heterozygous variants in the FOXF1 gene or microdeletions involving FOXF1. We present a male infant with ACDMPV, hypoplastic left heart sequence (HLHS), duodenal atresia, and imperforate anus due to a de novo, in frame deletion in FOXF1: c.209_214del (p.Thr70_Leu71del). Previous reports have suggested that microdeletions involving FOXF1 are associated with ACDMPV with congenital heart defects, including HLHS, gastrointestinal atresias, and other anomalies; whereas likely pathogenic variants within FOXF1 have not been reported with ACDMPV and HLHS. This is the first patient reported with ACDMPV, HLHS, imperforate anus, and duodenal atresia associated with a likely pathogenic variant in the FOXF1 gene. 相似文献
29.
Ejim LJ D'Costa VM Elowe NH Loredo-Osti JC Malo D Wright GD 《Infection and immunity》2004,72(6):3310-3314
The biosynthesis of methionine in bacteria requires the mobilization of sulfur from Cys by the formation and degradation of cystathionine. Cystathionine beta-lyase, encoded by metC in bacteria and STR3 in Schizosaccharomyces pombe, catalyzes the breakdown of cystathionine to homocysteine, the penultimate step in methionine biosynthesis. This enzyme has been suggested to be the target for pyridinamine antimicrobial agents. We have demonstrated, by using purified enzymes from bacteria and yeast, that cystathionine beta-lyase is not the likely target of these agents. Nonetheless, an insertional inactivation of metC in Salmonella enterica serovar Typhimurium resulted in the attenuation of virulence in a mouse model of systemic infection. This result confirms a previous chemical validation of the Met biosynthetic pathway as a target for the development of antibacterial agents and demonstrates that cystathionine beta-lyase is important for bacterial virulence. 相似文献
30.
Blacker D Bertram L Saunders AJ Moscarillo TJ Albert MS Wiener H Perry RT Collins JS Harrell LE Go RC Mahoney A Beaty T Fallin MD Avramopoulos D Chase GA Folstein MF McInnis MG Bassett SS Doheny KJ Pugh EW Tanzi RE;NIMH Genetics Initiative Alzheimer's Disease Study Group 《Human molecular genetics》2003,12(1):23-32
Alzheimer's disease (AD) is a devastating neurodegenerative disorder of late life with complex inheritance. Mutations in three known genes lead to the rare early-onset autosomal dominant form of AD, while a common polymorphism (epsilon 4) in the gene encoding apolipoprotein E (APOE ) is a risk factor for more typical late-onset (>60 years) AD. A recent study concluded that there are up to four additional genes with an equal or greater contribution to the disease. We performed a 9 cM genome screen of 437 families with AD, the full National Institute of Mental Health (NIMH) sample, which has been carefully ascertained, evaluated and followed by our group over the last decade. Performing standard parametric and non-parametric linkage analyses, we observed a 'highly significant' linkage peak by Lander and Kruglyak criteria on chromosome 19q13, which probably represents APOE. Twelve additional locations-on 1q23, 3p26, 4q32, 5p14, 6p21, 6q27, 9q22, 10q24, 11q25, 14q22, 15q26 and 21q22-met criteria for 'suggestive' linkage [i.e. two-point lod score (TLS) >/=1.9 and/or multipoint lod score (MLS) >/=2.2] in at least one of our analyses. Although some of these will surely prove to be false positives, these linkage signals should provide a valuable framework for future studies aimed at identifying additional susceptibility genes for late-onset AD. 相似文献