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C Gutierrez

Publications and source records attributed to C Gutierrez.

206 records · Page 12Linked to original sources
PubMedDate not supplied

Nasal nitric oxide is independent of nasal cavity volume.

This study was performed to evaluate the relationship between nasal nitric oxide (NO) and changes in nasal cavity volume resulting from the topical application of xylometazoline and saline and between upright and supine posture. Nasal NO was measured using a fixed high flow technique that avoids contamination with lower airways NO. In nine healthy subjects nasal NO concentration was measured by a rapid response chemiluminescent analyzer. A tapered tube was inserted in one nostril, into which room air was insufflated to produce a constant flow of 100 mL/second; another tube was inserted into the opposite nostril for NO sampling (air exit side). Subjects were instructed to keep the vellum closed while NO was sampled through a sideport connected to the analyzer. Nasal cavity volume was measured by acoustic rhinometry from a segment of the acoustic pathway, 2 to 5 cm from the nostril. Nasal cavity volume and NO measurements were made at baseline, 15 minutes, and 60 minutes after intervention (administration of saline 0.9%, xylometazoline or posture changes on 3 consecutive days). Xylometazoline produced a significant increase in nasal cavity volume, together with a significant reduction in NO level at 15 and 60 minutes after intervention. In addition, the change from seated to supine position decreased the total nasal volume significantly, but without changes in nasal NO. No correlation was found between the magnitudes of changes in nasal NO and the changes in nasal volume. Topical application of xylomethazoline resulted in increased nasal cavity volume and reduced NO output. In contrast to previous published reports, a technique using high flow rate insufflation demonstrated an abscence of correlation between the magnitudes of changes in nasal NO and nasal cavity volume brought about by decongestant, saline, or posture.

Acoustic Stimulation↗
PubMedDate not supplied

Nasal nitric oxide: a comparison of measurement techniques.

Nasal nitric oxide measurement may be a surrogate marker of upper airway inflammation. There is, however, no standardized measurement technique; and this led us to examine measurement techniques for acceptability and reproducibility. In five subjects we examined the flow dependence of nasal NO. In 13 healthy volunteers, nasal NO was measured on-line by five methods: 1) Tidal nasal and oral breathing: NO sampling during exclusive nasal followed by exclusive oral tidal breathing; 2) Fixed flow exhalation: NO sampling during exclusive nasal followed by exclusive oral exhalation at 100 mL/second from total lung capacity; 3) Nasal-oral aspiration: air aspirated from the mouth via both nares at 100 mL/second with glottis closure; 4) Aspiration from one nares: air aspirated from one nares at 3.3 mL/second using nitric oxide analyzer sample line with velum closure; 5) Nasal Insufflation: NO sampled at one nares as air insufflated into the other nares at a flow of 100 mL/second with velum closure. Acceptability of all methods was assessed by subjects and technicians. Nasal NO concentration showed a significant inverse correlation with transnasal flow rate. All methods showed excellent reproducibility as assessed by the intraclass correlation coefficient except tidal breathing, which showed highly variable breath-to-breath NO levels, although mean breath values were reproducible. Mean nasal NO concentrations with methods 1, 2, 3, 4, and 5 were 32.1, 50.2, 62.8, 1381, and 60.0 ppb, respectively. Velum closure was not always achieved in methods 4 and 5, whereas methods 1 and 2 required separate nasal and oral procedures. Method 5 had reduced acceptability. NO concentrations were similar with methods that used the same airflow (2, 3, and 5). Nasal NO can be sampled in different ways with excellent reproducibility. In view of the flow dependence of nasal NO, it is vital to use a constant flow rate, and lower airway NO contribution must be excluded or subtracted. The fixed flow exhalation appears to be the preferred method as it is highly reproducible and acceptable.

Analysis of Variance↗
PubMedDate not supplied

Group A streptococcal sepsis and ovarian vein thrombosis after an uncomplicated vaginal delivery.

BACKGROUND: Group A streptococcal puerperal sepsis is an uncommon peripartum infection that can quickly progress to a fulminant, multisystemic infection and life-threatening toxin-mediated shock. This infection can be asymptomatic during a short hospital stay after a routine delivery. Early treatment with antibiotics might not alter the course of tissue destruction caused by the exotoxin A. METHODS: Literature searches were performed using the key words "puerperal infections," "streptococcal infections," "septic sacroiliitis," "postpartum septic arthritis," and "postpartum ovarian vein thrombosis." After patient consent was obtained, a report was prepared documenting the disease course, diagnosis, and treatment of a case of puerperal sepsis with multiple serious complications. RESULTS AND CONCLUSION: Puerperal sepsis occurs when streptococci colonizing the genital tract or acquired nosocomially invade the endometrium, adjacent structures, lymphatics, and bloodstream. A lack of symptoms early in the course of infection is common; later, minor somatic complaints can quickly progress to septic shock as effects of the exotoxin A are manifest. Women who complain of fever, pelvic pain, or unexplained systemic symptoms in the early postpartum period should have a detailed history and physical examination. All sites of suspected infection should be cultured. If sepsis is suspected, diagnostic imaging includes chest radiographs, contrast-enhanced computed tomographic scans, or magnetic resonance imaging to rule out ovarian vein thrombosis, pelvic abscess, or sacroiliac septic arthritis. Broad-spectrum antibiotic coverage must be initiated immediately after collection of cultures. Clindamycin plus a beta-lactam antibiotic is preferred for streptococcal toxic shock syndrome.

Adult↗
PubMedDate not supplied

Automated spectrophotometric method using 2,2'-dithiodipyridine acid for determination of cholinesterase in whole blood.

An automated method using 2,2'-dithiodipyridine (2-PDS) as chromophore for determination of whole-blood cholinesterase activity was developed. Assay procedures, optimal concentrations of chromophore and substrate, detection limit, precision, backgrounds, and sensitivity of the method were compared with those of an earlier automated method based on the Ellman method and using 5,5'-dithiobis(2-nitrobenzoic acid) (DTNB) as chromophore. The new method has the advantages of automation (resulting in increase throughput rate and decrease in amount of reagents used) and good precision and sensitivity. Sample dilutions also are reduced in the new method because hemoglobin interference is less.

2,2'-Dipyridyl↗