Biomedical subjects

A Gungor

Publications and source records attributed to A Gungor.

At least 19 recordsLinked to original sources

PubMed2003

Evaluation of the outcomes of short bowel syndrome and indications for intestinal transplantation.

Long-term parenteral nutrition (PN) and intestinal transplantation (IT) are life-saving therapies for patients with short bowel syndrome (SBS). However, indications and timing of these therapies are controversial. In this study we aimed to evaluate the indications for IT. Forty-two patients, each with <100 cm of small bowel, were divided into three groups according to the length of remnant: group I patients (n = 18): colon plus 50 to 100 cm of small bowel (SB); group II patients (n = 14): colon plus <50 cm of SB; and group III patients (n = 10): <50 cm of SB without colon. One-year mortality rates for groups I, II, and III were 50%, 72%, and 100%, respectively. All group I survivors developed intestinal adaptation, returning to regular oral feedings at 1 year. Interestingly, three of four surviving patients in group II developed adaptation and were fed an oral short bowel diet (SBD) at 1 year. None of the group III patients survived >1 year, dying due to multiorgan failure in the early postoperative period or from sepsis within 1 year. We conclude that patients with a very short bowel are candidates for IT when stable. If the colon is intact, however, regardless of small bowel remnant length, the patient should be given a chance to develop intestinal adaptation before making the decision for permanent PN or IT.

Adolescent↗

PubMed2002

Single-photon tunneling via localized surface plasmons.

Strong evidence of a single-photon tunneling effect, a direct analog of single-electron tunneling, has been obtained in the measurements of light tunneling through individual subwavelength pinholes in a gold film covered with a layer of polydiacetylene. The transmission of some pinholes reached saturation because of the optical nonlinearity of polydiacetylene at a very low light intensity of a few thousand photons per second. This result is explained theoretically in terms of a "photon blockade," similar to the Coulomb blockade phenomenon observed in single-electron tunneling experiments. Single-photon tunneling may find applications in the fields of quantum communication and information processing.

Journal Article↗

PubMed2001

Antibiotic theory in otitis media.

Otitis media is currently the most common diagnosis made by clinicians, which has a major impact on managed care. The emergence of resistant bacterial pathogens has caused controversy over the use of antibiotics when acute otitis media (AOM) is diagnosed. All infants with AOM and all older children with severe AOM should be treated with antibiotics, despite concerns about rising rates of resistant bacterial pathogens. Some older children with nonsevere AOM may be candidates for initial observation, although this is not confirmed by clinical trials. Antimicrobial agents are not required for otitis media with effusion of recent onset but may be considered if this effusion becomes chronic; in these cases, tympanostomy tube placement may be indicated. Antimicrobial prophylaxis for prevention of recurrent AOM should be reserved for selected patients because of the possible emergence of resistant organisms. Tympanostomy tube placement is a more reasonable option today.

Anti-Bacterial Agents↗

PubMed2000

Location and gross morphology of the nasopalatine duct in human adults.

OBJECTIVE: To characterize the nasal opening of the human nasopalatine duct (NPD; a major duct of the vomeronasal system used in animals for chemical communication) by identifying its location, categorizing variations in physical characteristics, and assessing frequency of detection. DESIGN: Two studies: (1) general study incorporating endoscopic examinations documented by videotapes and photographs, and an investigation of detection bias in terms of method of visualization and defining criteria for NPD identification; and (2) cadaver dissections examining NPD gross anatomy and proximity to the putative vomeronasal organ (VNO), the second major duct of the vomeronasal system. SETTING: Department of Otolaryngology, University of Chicago Hospitals, Chicago, Ill. SUBJECTS: A total of 125 university community volunteers, with a mean age of 23 years. RESULTS: (1) General study: NPD was located 1.9+/-0.02 cm (mean+/-SEM) dorsal to the columella nasi, and 0.2+/-0.01 cm above the nasal floor/septum junction, in both nostrils (90% bilateral), and was symmetrical in shape. An NPD was detected in 94% of 221 nostrils unobstructed in the region of interest. Fossa shapes were oval (57%), round (18%), spindle-shaped (18%), and tubular (7%). A small, round aperture was visualized in 30% of fossae. Among 3 observers, NPD detection frequency ranged from 94% to 40%, with the disparity due to inclusion of different defining characteristics. (2) Cadaver dissection study: bilateral nasal NPD fossae were found in every specimen probed to maximum approximate depth of 8 mm. No buccal pits associated with patent NPD were detected. Putative VNOs superior and just anterior to NPD fossae were detected in fewer than half the specimens. CONCLUSIONS: The nasal opening of the NPD is bilateral and symmetrical, located at the base of the nasal septum. Unusually contradictory anatomical descriptions in the human putative VNO literature may be attributable to inexact descriptions or misidentification of structures. The function of NPD remains controversial.

Adolescent↗

PubMed2000

Pediatric obstructive sleep apnea syndrome.

Pediatric obstructive sleep apnea occurs in about 2% of children, and manifests as snoring, difficulty breathing, and witnessed apneic spells. Daytime symptoms include excessive sleepiness with poor performance and behavior problems. Severe forms may be associated with failure-to-thrive or death. The gold standard diagnostic procedure is overnight polysomnography and is indicated in high-risk patients. While most pediatric patients with obstructive sleep apnea can be treated with tonsillectomy and adenoidectomy; uvulopalatopharyngoplasty, tracheotomy, or other procedures are sometimes indicated. Nonsurgical treatment with continuous positive airway pressure is used in some children. Postoperative management in high-risk children includes careful perioperative monitoring and postoperative polysomnography.

Child↗

PubMed2000

ImmunoCAP and HY*TEC enzyme immunoassays in the detection of allergen-specific IgE compared with serial skin end-point titration by receiver operating characteristic analysis.

OBJECTIVES: In this study, we compared 2 different immunoassays, HY*TEC enzyme immunoassay (Hycor Biomedical Inc, Garden Grove, CA) and Pharmacia Upjohn ImmunoCAP (Pharmacia and Upjohn, Kalamazoo, MI) using skin end-point titration as a gold standard by receiver operating characteristic analysis. MATERIALS: One hundred patients were enrolled in this study and were tested with the above 3 modalities. The results were analyzed by receiver operating characteristic analysis, in which the curves give a decision criterion for any diagnostic test relative to its sensitivity and specificity against an accepted gold standard test. Only inhalant allergens (Dermatophagoides pteronyssinus, Dermatophagoides farina, cat dander, giant ragweed, English plantain weed, timothy grass, Alternaria tenuis, Aspergillus fumigatus, meadow fescue, oak tree, white ash tree, and lamb's-quarter weed) were studied. RESULTS: The results obtained with both ImmunoCAP and HY*TEC showed a good correlation with skin end-point titration for D pteronyssinus, D farina, cat dander, giant ragweed, timothy grass, A tenuis, and meadow fescue, with sensitivities ranging from 71% to 88%. However, the sensitivity of both tests to English plantain weed, lamb's-quarter weed, oak tree, and white ash tree was lower (66% down to 39%). Additionally, HY*TEC results were not satisfactory for detecting specific IgE to A fumigatus (30% sensitivity). The overall sensitivity for each test was 65.67% for the HY*TEC and 71.25% for the ImmunoCAP. CONCLUSION: The 2 in vitro testing systems are comparable for most of the allergens, except for A fumigatus, English plantain, lamb's-quarter, and white ash tree; ImmunoCAP and HY*TEC would benefit from improved technology for detecting these specific IgE antibodies. The HY*TEC assay did not give acceptable results for A fumigatus. The overall assay characteristics were good to excellent for each system tested.

Adolescent↗

PubMed2000

Loratadine/pseudoephedrine for nasal symptoms in seasonal allergic rhinitis: a double-blind, placebo-controlled study.

In this double-blind, placebo-controlled, crossover, parallel study, we treated 20 adults who had seasonal allergic rhinitis with once-daily fixed-combination loratadine/pseudoephedrine sulfate to observe its effect on relieving symptoms, primarily nasal congestion. Acoustic rhinometry detected a trend toward improvement in nasal patency, although the difference between pre- and post-treatment measures was not statistically significant. Endoscopic inferior turbinate photography documented that treatment led to statistically significant reductions in the amount of nasal edema and nasal secretions. The results of a quality-of-life questionnaire suggested that treatment alleviated nasal and ocular symptoms of rhinoconjunctivitis. An analysis of subjective visual analog scale scores showed a trend toward improvement in most but not all nasal symptoms. We conclude that once-a-day fixed-combination loratadine/pseudoephedrine is effective in relieving nasal congestion in patients with seasonal allergic rhinitis.

Adult↗

PubMed1999

Effect of nasal surgery on the nasal cavity as determined by acoustic rhinometry.

Acoustic rhinometry (AR) was used to objectively measure the success of septoplasty in relieving nasal obstruction caused by septal deviation. In addition, the patients were given a questionnaire to subjectively assess symptoms of congestion, rhinorrhea, and sneezing. Patients diagnosed with a septal deviation requiring surgery to eliminate obstruction were enrolled in this study. A septal deviation often results in concomitant sinonasal or respiratory problems that require septoplasty plus other surgeries to treat the patient effectively. AR measurements for patients who underwent septoplasty or septoplasty plus other surgeries were taken before and after surgery. To avoid confounding results caused by different levels of congestion, we used only postdecongestant values to analyze the data and only the side of the nose with the smaller volume for analysis. Patients in the septoplasty-only group showed a statistically significant (P < 0.01) increase in volume as measured by AR, a decrease in the symptom of congestion, and a decrease in the symptom of rhinorrhea. Patients who had septoplasty plus other sinonasal procedures showed significant increases in volume and cross-sectional area (CSA) 3, whereas CSAs 1 and 2 increased also, but not significantly.

Adult↗

PubMed1999

Decreased neuropeptide release may play a role in the pathogenesis of nasal polyps.

In this in vivo prospective, controlled study, we have examined the capsaicin-induced levels and secretion patterns of the colocalized neuropeptides substance P, calcitonin gene-related peptide (CGRP), and neurokinin A in nasal secretions of subjects with nasal polyps, and we compared these with secretion patterns from healthy subjects and from subjects with allergic rhinitis. Capsaicin was used to elicit neuropeptide release. The neuropeptide levels were measured by an ELISA technique. For substance P, subjects with nasal polyps responded very poorly to capsaicin stimulation. The atopic group was more reactive to capsaicin stimulation than control subjects. For CGRP the increase was immediate in all groups. Atopic subjects and subjects with polyps had a less pronounced but sustained response to capsaicin stimulation. CGRP levels in atopic subjects and those with polyps were restored rapidly. Atopic subjects had higher neurokinin A levels with an immediate and sustained response to capsaicin. Control subjects had higher levels than those with polyps, but both groups were nonresponsive to capsaicin stimulation.

Adolescent↗

PubMed1999

Detection of the nasal cycle with acoustic rhinometry: techniques and applications.

Acoustic rhinometry is an appropriate method for detecting and recording the nasal cycle in normal subjects in terms of the cross-sectional areas and volume of the nasal cavity. In this study, we tried to detect and to define the nasal cycle in normal subjects so that we might develop a reliable and reproducible technique to be used in conjunction with studies on the physiology and pathology of nasal disease. We used normal volunteer adult subjects and performed bilateral acoustic rhinometry measurements every 15 minutes over 4 hours, along with the use of a visual analog scale for assessment of the subjective feeling of congestion (or patency) just before each acoustic rhinometry measurement. Volume and cross-sectional area changes were observed along with subjective patency-score changes in each subject. The subjective feeling of patency was not related to the volume and cross-sectional area changes measured simultaneously. The technique of recording the nasal cycle with acoustic rhinometry in nasal research is presented.

Acoustics↗

PubMed1999

Comparison of the response to histamine challenge of the nose and the maxillary sinus: effect of loratadine.

To study the response of the maxillary sinus to histamine provocation, we performed a double-blind, randomized, crossover trial during which nonallergic subjects without symptoms of rhinitis (n = 25) received either 10 mg loratadine or placebo once daily for a week and then underwent nasal challenge with histamine (3, 10, and 30 mg/ml) followed, 24 h later, by a maxillary sinus challenge while still receiving the medication. Nasal challenge with histamine led to significant increases in vascular permeability, reflex nasal secretions, sneezing, and other nasal symptoms. Sinus challenge resulted in significant increases in vascular permeability within the sinus cavity (P < 0.01) and some nasal symptoms but no significant change in reflex nasal secretions. The response of the sinus mucosa to histamine was lower in magnitude than that of the nose. Treatment with loratadine resulted in a significant inhibition of the histamine-induced changes in both nasal and sinus cavities. Our data suggest the lack of a sinonasal reflex response to histamine provocation of the maxillary sinus of nonallergic individuals.

Adult↗

PubMed1998

Allergy for the laryngologist.

Allergic disease can affect any portion of the respiratory tract, including the larynx, trachea, bronchial tree, nasal cavity, paranasal sinuses, nasopharynx, and pharynx. This review evaluates laryngeal manifestations of allergic disease and the impact of allergic mechanisms in disorders, within the scope of laryngology.

Anti-Allergic Agents↗

PubMed1998

Normative standards for nasal cross-sectional areas by race as measured by acoustic rhinometry.

Acoustic rhinometry evaluates the geometry of the nasal cavity with acoustic reflections and provides information about nasal cross-sectional area and nasal volume within a given distance. Variations in internal nasal diameters have attracted increased interest since the advent of endoscopic surgical techniques. Race is known to be one of the most important factors affecting the nasal structure. In this study, we evaluated 106 healthy adult volunteers with acoustic rhinometry to determine internal nasal diameters and volumes and obtained normative data for four racial/ethnic groups. The data were analyzed with regard to race, sex, height, and weight. All measurements were made before and after the application of a topical nasal decongestant so that the effects of the nasal cycle were eliminated by decongestion.

Acoustics↗

PubMed1998

Fungal sinusitis: progression of disease in immunosuppression--a case report.

Fungal sinusitis is a disease which can be grouped into invasive and noninvasive forms. The invasive entities include the acute/fulminant and chronic/indolent forms. The noninvasive entities include the fungus ball and allergic forms. The noninvasive forms, however, can develop into invasive disease under certain immunosuppressive states. The patient in this case report had the fungus ball form of fungal sinusitis which evolved into chronic, and then the acute/fulminant form approximately two weeks after undergoing cadaver-donor kidney transplantation. Due to the patient's immunosuppressed state, the fungus spread beyond the sinus region and eventually lead to fulminant disseminated disease. The severity of the fungal disease corresponded directly to the severity of the patient's immunosuppression.

Aspergillosis↗

PubMed1997

A comparison of the nasal cross-sectional areas and volumes obtained with acoustic rhinometry and magnetic resonance imaging.

Acoustic rhinometry (AR) evaluates the geometry of the nasal cavity with acoustic reflections and provides information about nasal cross-sectional areas (CSA) and nasal volume within a given distance. The accuracy of the information obtained by AR was compared with that of magnetic resonance imaging (MRI) of the nasal cavity. Five healthy subjects were evaluated with AR and the MRI before and after the application of a long-acting nasal decongestant spray, to eliminate possible interference of the nasal cycle with both measurement techniques. The MRI images of 2 mm coronal sections of the nasal cavity were traced by three independent observers and the CSAs were calculated by computer-aided imaging digitization, to be compared with the calculated CSAs obtained with the AR at the corresponding distance from the nasal tip. Digitized data from the MRI images were also used to calculate the nasal volume within the first 6 cm from the nasal tip and compared with the AR volume measurements. The interobserver variation of digitized MRI data predecongestant and postdecongestant was not significant. The correlations of CSA and volume measurements between the AR and MRI were high (0.969) after the application of the decongestant. The correlation between the AR and MRI measurements before the decongestant was low (0.345). This may have been the result of interference of the nasal cycle during the long MRI measurements (1 hour) or other unknown factors. We conclude that AR measurements of nasal CSAs and volumes provide accurate information when compared with the MRI of the decongested nasal airway.

Acoustics↗

PubMed1997

Prevalence of mold-specific immunoglobulins in a Midwestern allergy practice.

Mold allergy surveys are an important part of the correct identification and treatment of mold allergies. This study included 100 patients who were referred to a Midwestern allergy clinic for the evaluation of rhinitis, suspected to be of allergic origin. An in vitro screening test for allergen-specific IgE (ImmunoCAP) comprised of 10 allergens, including Candida, Aspergillus, Helminthosporium, and Alternaria, was used. To assess the seasonal distribution of mold allergies, we randomly selected 8 patients out of the 100 from each season during which the clinical contact occurred, and we tested them for 14 varieties of mold. The overall incidence of mold allergy in atopic subjects was 44%. The most common molds were (in descending order of frequency) Alternaria, Helminthosporium, Aspergillus, Candida, and Curvularia. Mold allergy was diagnosed most frequently in the winter; the second highest period was the fall. Population surveys of IgE antibody sensitization by in vitro techniques can provide useful information about fungal allergy.

Adolescent↗

PubMed1997

Evaluation of the nasal cavity by acoustic rhinometry in normal and allergic subjects.

With acoustic rhinometry, one can detect a difference in response to a topical decongestant between normal and allergic subjects at the minimal cross-sectional area. The minimal cross-sectional area corresponds in most cases to the anterior end of the inferior turbinate or the first valley, which occurs after the nose piece of the acoustic rhinometer on the acoustic rhinometry graph. Allergic patients typically have an increase in nasal mucosal swelling, which leads to a decrease in the nasal volume and area and, subsequently, to an increase in congestion. In this study acoustic rhinometry was used to test normal and allergic subjects before and after the application of a topical decongestant (1% phenylephrine (Neo-Synephrine)). Symptoms were measured by a five-point scale. Results showed that increasing symptom scores demonstrated a trend toward being related to decreasing area as measured at the minimal cross-sectional area or nasal valve. The average total percent change at the minimal cross-sectional area was calculated for both groups and compared. The normal subjects had an average total percent area change at the minimal cross-sectional area of 15.6% +/- 14.8%, and the allergic subjects had a percent change of 24.6% +/- 20.8%. This represents a significant difference between the normal and allergic subjects in response to the topical decongestant at the minimal cross-sectional area (p = 0.04). However, the average total percent change was not significantly different between the two groups at the second and third valleys. At the second valley, the normal subjects had a percent change of 40% +/- 17.5%, and the allergic subjects had a percent change of 36% +/- 18.5%. At the third valley, the normal subjects had a percent change of 35% +/- 15.4%, and the allergic subjects had a percent change of 32% +/- 20.6% (p = 0.4 and 0.5, respectively). The total area was calculated by adding measurements from both right and left nasal cavities for each subject in an attempt to control the effect of the nasal cycle. Acoustic rhinometry makes it possible to detect a trend in the relationship between either a decrease in area at the minimal cross-sectional area or a decrease in the total volume from 0 to 7 cm into the nasal cavity and congestion. A statistically significant difference between normal and allergic subjects in their response to a topical decongestant at the minimal cross-sectional area was detected by acoustic rhinometry at the nasal valve.

Acoustics↗

PubMed1997

Pediatric sinusitis: a literature review with emphasis on the role of allergy.

Evaluation and treatment of pediatric sinusitis is a challenging area that has been subject to many different opinions and options during the past decade. Sinusitis is among the most commonly encountered diseases of childhood and has been the major area of interest for many otolaryngologists, allergists, and pediatricians. We have searched the medical literature to review the many aspects of the problem and the opinions of various authors. The increasing importance of allergic diseases and their relationship to sinus disease have been evaluated through a review of relevant literature. The poorly understood variations of the presentation of sinusitis and its signs and symptoms in the pediatric age group have been reviewed. Recommendations concerning the method, duration, and timing of the therapeutic intervention or interventions are summarized. The natural course of pediatric sinusitis in association with related respiratory tract diseases is discussed. Allergies and viral upper respiratory infections are among the most common predisposing factors of sinus disease. Every child with sinusitis is a candidate for an allergy evaluation.

Child↗