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41.
42.
Esophageal chest pain 总被引:1,自引:0,他引:1
Captain Carol A. Lee MD James C. Reynolds MD Dr. Ann Ouyang MD Lori Baker BA Sidney Cohen MD 《Digestive diseases and sciences》1987,32(7):682-688
The unequivocal diagnosis of esophageal chest pain requires the demonstration of simultaneous manometric changes and chest pain. Numerous provocative agents have been used to enhance the diagnostic value of esophageal manometry. Our aims were to: evaluate consecutively a large group of patients with proven noncardiac chest pain and normal baseline manometric studies, using edrophonium chloride, 10 mg, and determine the value of provocative testing in clinical practice. One hundred twenty patients with normal standard baseline esophageal manometries were studied using blinded testing with edrophonium chloride and followed clinically by questionnaire. A positive response of both chest pain and manometric changes was observed in 34%, a negative response in 49%, and an indeterminate response in 17% of patients. Baseline manometric features, including high-amplitude contractions, did not predict the response to edrophonium chloride. Following edrophonium chloride administration, the change in amplitude, duration, and number of repetitive contractions from baseline was significantly greater in positive responders. Edrophonium decreased the velocity of propagated contractions in positive responders (P less than 0.05), but not in nonresponders. Response to edrophonium chloride could not be predicted by patient age, sex, or clinical symptomatology. Seventy percent of patients in both groups had symptoms indistinguishable from ischemic heart disease. After making a specific diagnosis of esophageal chest pain, patients showed a marked clinical improvement, with a significant decrease in physical limitation, emergency room visits, hospital and CCU admissions, and in further cardiac testing. We conclude that provocative testing with edrophonium chloride will make it possible to definitively implicate the esophagus in over 30% of patients with normal baseline manometric findings and noncardiac chest pain. 相似文献
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Holland Charity A. McElhoe Jennifer A. Gaston-Sanchez Sidney Holland Mitchell M. 《International journal of legal medicine》2021,135(1):91-106
International Journal of Legal Medicine - Massively parallel sequencing (MPS) of mitochondrial (mt) DNA allows practitioners the ability to fully resolve heteroplasmic sites. In forensic DNA... 相似文献
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Thamyres Fernandes Messa Moreira Sidney Aquino Neto Charly Lemoine Kouakou Boniface Kokoh Cludia Morais Teko Wilhelmin Napporn Paulo Olivi 《RSC advances》2020,10(58):35310
The development of efficient catalysts for ethanol oxidation in alkaline medium requires a synthetic approach that may prevent the surfactant molecules from being adsorbed at the catalytic sites and decreasing the electrochemical performance of the final direct ethanol fuel cell. Toward this goal, the recently reported surfactant-less Bromide Anion Exchange (BAE) method, appears as a promising route to conveniently aim at preparing PtRh alloys dispersed on carbon substrates. The catalysts prepared herein by the BAE method were characterized physicochemically to obtain structural information on the PtRh/C nanomaterials, their morphology (size and shape), and their chemical and surface composition. Electrochemical behavior and properties of these electrodes were then investigated in a half-cell before the implementation of a direct ethanol fuel cell (DEFC) in a home-made anion exchange membrane Teflon cell. The analysis of the electrolytic solution in the anodic compartment by chromatography revealed that acetate was the major reaction product and the carbonate amount increased with the Rh content in the bimetallic composition. With 2.8–3.6 nm particle sizes, the Pt50Rh50/C catalyst exhibited the highest activity towards the ethanol electrooxidation.The development of efficient catalysts for ethanol oxidation in alkaline medium requires an approach that avoids surfactant molecules from being adsorbed at active sites and decreasing the electrochemical performance of the direct ethanol fuel cell. 相似文献
47.
Steady-state intrapulmonary concentrations of moxifloxacin, levofloxacin, and azithromycin in older adults 总被引:5,自引:0,他引:5
STUDY OBJECTIVE: To determine the steady-state, extracellular, and intracellular pulmonary disposition of moxifloxacin (MXF), levofloxacin (LEVO), and azithromycin (AZI) relative to that of the plasma over a 24-h dosing interval. DESIGN: Randomized, multicenter, open-label investigation. PATIENTS: Forty-seven older adults (mean [+/- SD] age, 62 +/- 13 years) undergoing diagnostic bronchoscopy. INTERVENTIONS: Oral administration of MXF, 400 mg, LEVO, 500 mg daily for five doses, or AZI, 500 mg for one dose, then 250 mg daily for four doses. BAL and venipuncture were completed at 4, 8, 12, or 24 h following the administration of the last dose. MEASUREMENTS AND RESULTS: Steady-state MXF, LEVO, and AZI concentrations were determined in the plasma, epithelial lining fluid (ELF), and alveolar macrophages (AMs). The concentrations of all three agents were greatest in the AMs followed by the ELF compared to the plasma. Plasma concentrations were similar to those previously reported with these agents. The mean ELF concentrations at 4, 8, 12, and 24 h were as follows: MXF, 11.7 +/- 11.9, 7.8 +/- 5.1, 10.5 +/- 3.7, and 5.7 +/- 6.3 micro g/mL, respectively; LEVO, 15.2 +/- 4.5, 10.2 +/- 6.7, 6.9 +/- 4.4, and 2.9 +/- 1.7 micro g/mL, respectively; and AZI, 0.6 +/- 0.4, 0.7 +/- 0.4, 0.9 +/- 0.5, and 0.9 +/- 0.7 micro g/mL, respectively. The AM concentrations at 4, 8, 12, and 24 h were as follows: MXF, 47.7 +/- 47.6, 123.3 +/- 126.4, 26.2 +/- 19.4, and 32.8 +/- 16.5 micro g/mL, respectively; LEVO, 28.5 +/- 30.2, 26.1 +/- 15.7, 28.3 +/- 12.6, and 8.2 +/- 6.1 micro g/mL, respectively; and AZI, 71.8 +/- 50.1, 73.8 +/- 75.3, 155.9 +/- 81.3, and 205.2 +/- 256.3 micro g/mL, respectively. CONCLUSIONS: The intrapulmonary concentrations of MXF, LEV, and AZI were superior to those obtained in the plasma. The AM concentrations of all agents studied were more than adequate relative to the minimum concentration required to inhibit 90% of the organism population (MIC(90)) of the common intracellular pathogens (< 1 micro g/mL). These data indicate that attainable extracellular concentrations of AZI are insufficient to reliably eradicate Streptococcus pneumoniae, based on the agent's current minimum inhibitory concentration profile, whereas the mean concentrations of MXF and LEVO in the ELF exceed the MIC(90) of the S pneumoniae population. Moreover, MXF concentrations exceeded the S pneumoniae susceptibility breakpoint (1.0 micro g/mL) at all time points, while 2 of 15 concentrations (13%) failed to maintain LEVO concentrations above the breakpoint (2.0 micro g/mL) throughout the dosing interval. 相似文献
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Edna Cleide Mendes Muricy Romilda Aparecida Lemes Sidney Bombarda Lucilaine Ferrazoli Erica Chimara 《Revista do Instituto de Medicina Tropical de S?o Paulo》2014,56(5):397-401
New methodologies were developed for the identification of
Nocardia but the initial diagnosis still requires a fast
and accurate method, mainly due to the similarity to
Mycobacterium, both clinical and bacteriologically. Growth
on Löwenstein-Jensen (LJ) medium, presence of acid-fast bacilli
through Ziehl-Neelsen staining, and colony morphology can be confusing aspects
between Nocardia and Mycobacterium. This study
describes the occurrence of Nocardia spp. in a
mycobacterial-reference laboratory, observing the main difficulties in
differentiating Nocardia spp. from
Mycobacterium spp., and correlating isolates with
nocardiosis cases. Laboratory records for the period between 2008 and 2012 were
analyzed, and the isolates identified as Nocardia sp. or as
non-acid-fast filamentous bacilli were selected. Epidemiological and
bacteriological data were analyzed as well. Thirty-three isolates identified as
Nocardia sp. and 22 as non-acid-fast bacilli were selected
for this study, and represented 0.12% of isolates during the study period.
The presumptive identification was based on macroscopic and microscopic
morphology, resistance to lysozyme and restriction profiles using the
PRA-hsp65 method. Nocardia spp. can grow
on media for mycobacteria isolation (LJ and BBL MGIT™) and
microscopy and colony morphology are very similar to some mycobacteria species.
Seventeen patients (54.8%) were reported and treated for
tuberculosis, but presented signs and symptoms of nocardiosis. It was concluded
that the occurrence of Nocardia sp. during the study period was
0.12%. Isolates with characteristics of filamentous bacilli, forming aerial
hyphae, with colonies that may be pigmented, rough and without the BstEII
digestion pattern in PRA-hsp65 method are suggestive of
Nocardia spp. For a mycobacterial routine laboratory, a
flow for the presumptive identification of Nocardia is
essential, allowing the use of more accurate techniques for the correct
identification, proper treatment and better quality of life for patients. 相似文献