Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “RESPIRATORY TRACT”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,351 records · Page 75Linked to original sources
PubMedDate not supplied

Glycyl-L-glutamine-enriched total parenteral nutrition maintains small intestine gut-associated lymphoid tissue and upper respiratory tract immunity.

BACKGROUND: i.v. administration of a total parenteral nutrition (TPN) solution results in small intestinal gut-associated lymphoid tissue (GALT) atrophy, lowers small intestinal immunoglobulin A (IgA) levels, and impairs upper respiratory tract secretory IgA-mediated mucosal immunity; isonitrogenous supplementation of TPN with 2% glutamine attenuates these changes. This experiment examines whether a 2% glycyl-L-glutamine-enriched TPN solution reverses i.v. TPN-induced changes as effectively as L-glutamine. METHODS: Male Institute of Cancer Research (ICR) mice underwent intranasal inoculation with H1N1 influenza virus to establish immunity. After 3 weeks, mice were randomized to chow, i.v. feeding of a TPN solution, glutamine-enriched TPN, or glycyl-L-glutamine-enriched TPN. After 4 days of feeding, mice were challenged intranasally with influenza virus and killed at 40 hours to determine viral shedding from the respiratory tract; normal convalescent mice do not shed virus because they possess intact IgA-mediated mechanisms Lymphocytes were isolated from Peyer's patches, the intraepithelial layer, and lamina propria to determine cell yields. RESULTS: Total lymphocyte yield in the Peyer's patches, the intraepithelial layer, and lamina propria decreased with TPN but remained normal with glutamine and glycyl-L-glutamine. Upon challenge, 70% of the mice in the TPN group shed virus in nasal secretions, whereas only 20% of the glutamine-treated group, 18% of glycyl-L-glutamine group and none of the Chow group were virus positive. CONCLUSIONS: L-Glutamine and glycyl-L-glutamine have similar effects on i.v. administered TPN-associated (GALT) atrophy and decreased upper respiratory tract immunity.

Animal Nutritional Physiological Phenomena↗
PubMed1982

A case of IgA nephropathy associated with marked hematuria after upper respiratory tract infections.

IgA nephropathy is characterized by recurrent hematuria which is occasionally associated with upper respiratory infections. Since serial follow-up of IgA nephropathy has not been reported, a 43 year old patient who showed a typical course of this disease is described. Hematuria was markedly increased each time after upper respiratory infections. Renal biopsy revealed typical features of IgA nephropathy by light and immunofluorescent microscopy. Marked hematuria subsided after administration of antibiotics. Upper respiratory tract infections might be a risk factor in some patients with IgA nephropathy. In some patients upper respiratory tract infections may exacerbate IgA nephropathy.

Adult↗
PubMed1985

Respiratory tract infections. Goals for 1995.

Goals to be identified for 1995, a decade hence, in the prevention, diagnosis, and management of respiratory tract infections may conveniently be divided into diagnostic goals and goals in therapy and prophylaxis. Major diagnostic goals for bacterial, viral, and mycoplasmal infections of the respiratory tract focus on the development of systems to identify microbial components, such as specific antigens or segments of DNA, using monoclonal antibody techniques or DNA probes for hybridization. Sputum cultures, in the traditional sense, should ultimately become obsolete. Management goals include the development of algorithms to identify patients who should be hospitalized, in contrast to those who can safely be treated on an outpatient basis. New antibiotic drug development should include drugs active against methicillin-resistant staphylococci, broad-spectrum beta-lactam drugs that are orally active against gram-negative bacilli, and drugs that can be used parenterally on a once-daily basis in settings other than the acute care hospital. There are certainly needs to enhance the present spectrum of antiviral drugs and to develop therapeutically useful immunomodulators. There are promising prospects for vaccine development, including live attenuated influenza virus vaccine, parainfluenza virus vaccine, respiratory syncytial virus vaccine, and a Mycoplasma pneumoniae vaccine. With major research support, such vaccines could possibly be fully developed by 1995. Finally, of greatest importance is the need to achieve greater utilization of existing vaccines, that is, inactivated influenza vaccine and the current 23-valent pneumococcal vaccine. A legitimate goal for 1995 would be to achieve 70 percent or greater utilization of these vaccines within the recommended target populations.

Anti-Bacterial Agents↗
PubMed2001

The prevalence of potential pathogenic bacteria in nasopharyngeal samples from individuals with a respiratory tract infection and a sore throat--implications for the diagnosis of pharyngotonsillitis.

BACKGROUND: Treatment failure in patients with pharyngotonsillitis after a traditional course of penicillin V is a common finding. Several factors have been proposed to explain the failure rate, but the presence of aetiological agents other than group A beta-haemolytic streptococci has attracted little attention. OBJECTIVES: The aim of the present study was to investigate if a nasopharyngeal sample could suggest the aetiology of a sore throat in patients with a respiratory tract infection. METHODS: The prevalence of potentially pathogenic bacteria (Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis) in nasopharyngeal samples from 618 healthy individuals was compared with that from 108 patients with a respiratory tract infection and a sore throat. RESULTS: The prevalence of H.influenzae was higher in patients with a sore throat than in healthy individuals of the same age. For the adult patients with a sore throat, the prevalence was 27.5% compared with 2.7% for the healthy carriers (P < 10(-7)). The corresponding figures for schoolchildren were 31.3% versus 6.1% (P = 0.004) and for pre-school children 37.8% versus 13.2% (P = 0.0003). CONCLUSIONS: If H.influenzae is found in a nasopharyngeal sample from a patient with a respiratory tract infection and a sore throat, it might be the aetiological agent.

Adolescent↗
PubMed1988

[Per rectal administration of antibiotics. Clinical use of ampicillin in respiratory tract infection in children].

As one of our clinical studies on per rectal administration of antibiotics, children who suffered respiratory tract infection (RTI) were administered with ampicillin (ABPC) through this route. Our conclusions drawn from this study are as follows: 1. One hundred and eighty strains of aerobic bacteria which were isolated by us in 1984-1985 were tested for the sensitivity to ABPC using plate-disk method. MIC's of ABPC for all the strains of Streptococcus pyogenes were lower than 0.024 micrograms/ml. MIC's for all the strains of Streptococcus haemolyticus were 0.05-0.20 microgram/ml. MIC's for 88% of the strains tested of Haemophilus influenzae were 0.10-0.78 microgram/ml. 2. Bacterial flora in the respiratory tract of 97 cases of children, who suffered RTI, were cultured. Almost half of them were Gram-positive cocci, the rest belonged to Gram-negative groups. This indicates that broad-spectrum antibiotics should be chosen first even before the diagnosis of causative organisms is established. 3. Soon after a per rectal administration of ABPC to children, high blood concentrations of the drug were observed by paper-disk method. 4. Eleven cases, which included 2 cases of pneumonia, of 15 children who suffered RTI and were given this antibiotic were greatly improved within 3-10 days. No serious side effects were observed. 5. Our brief study reported here indicates that ABPC administration by rectal route is safe and useful for the clinical treatment of RTI of children.

Age Factors↗
PubMed1988

[Clinical experience with ofloxacin in the treatment of chronic respiratory tract disease aggravated by acute infection].

We studied the clinical usefulness of ofloxacin (OFLX) in 13 patients with chronic respiratory tract diseases aggravated by acute infections with identified causative bacteria. 1. Overall clinical efficacies were: highly effective 5, effective 6, slightly effective 2, and ineffective none, showing an efficacy rate of 84.6%. 2. In 6 patients with fever of over 37 degrees C, time lengths in days for symptoms to have been alleviated due to OFLX treatment were; 1 day: 4 cases, 3 days: 1 case and 5 days: 1 case (2.0 days on average). 3. As to bacterial transitions, in 9 of 10 patients Haemophilus influenzae was eliminated and in 1 patient it was substituted by Pseudomonas aeruginosa. In 3 patients Branhamella catarrhalis was eliminated and in 1 patient, the number of P. aeruginosa was reduced. OFLX is expected to have a potent bacteriological effect on H. influenzae and B. catarrhalis. 4. As to side effects, 1 of the 13 patients (7.7%) complained of discomfort in the epigastrium. This discomfort disappeared when a gastric mucosa protective agent was administered. There was no abnormality in laboratory test values. Judging from the above results, we consider OFLX a useful drug for the treatment of patients with chronic respiratory tract diseases aggravated by acute infections.

Acute Disease↗
PubMed1994

Inflammatory markers of lower respiratory tract infection in elderly people.

Bacterial infections of the respiratory tract are a major cause of morbidity and mortality in elderly people. The inflammatory response to such infection is an important protective process and has been suggested to be less effective in elderly patients. To investigate the inflammatory response in respiratory infections acquired in the community by elderly people we studied 52 consecutive patients who met the criteria for either a non-pneumonic chest infection or pneumonia. After exclusion, 41 patients were available for evaluation, with 25 fulfilling the criteria of pneumonia and 16 the criteria of chest infection. Pyrexia was a feature of the patients with pneumonia. Circulating levels of neutrophil elastase-alpha-1-antitrypsin complex and C-reactive protein were greater in the patients with pneumonia than in those with a chest infection and were reduced following antibiotic treatment. No changes occurred in the chest infection group for these markers of inflammation. In both groups, a further neutrophil granule protein, lactoferrin, was unaffected by antibiotic treatment. This study indicates that elderly patients with pneumonia can initiate an appropriate inflammatory response as demonstrated by clinical indicators and circulating mediators of the inflammatory response.

Age Factors↗
PubMed1993

Fetal upper respiratory tract function in cases of antenatally diagnosed congenital diaphragmatic hernia: preliminary observations.

Fetal upper respiratory tract function was studied in five cases of antenatally diagnosed congenital diaphragmatic hernia and in 16 cases of uncomplicated pregnancy at gestational ages ranging from 27 to 38 weeks. The evaluation of fetal upper respiratory tract function was performed using ultrasonography combined with color-flow and spectral Doppler analysis. In all cases with uncomplicated pregnancy, fetal breathing-related nasal and oropharyngeal fluid flow was seen at the level of the nose. The five cases with congenital diaphragmatic hernia all demonstrated fetal breathing activity by thoracic wall movement. In four of the fetuses, perinasal fluid flow was seen by the Doppler technique. The fetus with no demonstrated perinasal flow during breathing movements died in the early neonatal period and had pulmonary hypoplasia. Observation of the fetal breathing-related nasal and oropharyngeal fluid flow in cases of antenatally diagnosed congenital diaphragmatic hernia provides a rationale to hypothesize that the absence of this phenomenon is a useful marker for prenatal prediction of pulmonary hypoplasia.

Journal Article↗
PubMedDate not supplied

Radionuclide detection of gastroesophageal reflux in children suffering from recurrent lower respiratory tract infection.

Radionuclide gastro-esophageal scintigraphy was performed on 25 control and 183 children suffering from recurrent lower respiratory tract infection. Gastro-esophageal reflux (GER) of varying grades was observed in 135 patients. The severity of clinical symptoms in the patients was found to be directly related to the severity of reflux observed in the radionuclide study. In some patients an attempt was also made to quantitate GER by calculating the Gastro-esophageal reflux index. The results of the scintigraphic study were correlated with the results of the other commonly used and more conventional Barium swallow and fluoroscopy study. Gastro-esophageal scintigraphy was found to be much superior in terms of sensitivity, specificity and accuracy in detecting GER. It was also possible to objectively evaluate and monitor response to treatment following conservative or corrective surgical therapy using the radionuclide technique. The results of the study demonstrated a remarkably high incidence of GER in the patients. Whether GER is the cause of recurrent lower respiratory tract infection or not is difficult to establish firmly. But within the preview of the study the association seems to be very strong and cannot be easily ignored.

Child↗
PubMed1999

[Influence of respiratory viruses, cold weather and air pollution in the lower respiratory tract infections in infants children].

BACKGROUND: All winters, there is an increase in the number of pediatric consultations, associated to three factors: cold weather, air pollution and respiratory virus epidemics. AIM: To study the influence of these three factors in the demand for pediatric consultations between March and September, in an area of Metropolitan Santiago. PATIENTS AND METHODS: The number of consultations between March and September 1998 in the emergency room and the number of hospital discharges due to lower respiratory tract infections, were registered in a public pediatric hospital of Santiago. A respiratory virus surveillance (respiratory syncytial virus, adenovirus, influenza and parainfluenza virus) was done among children admitted for lower respiratory infections. Atmospheric temperature values and air pollution, measured as the number of particles of 10 microns or more per m3 (MP 10), were obtained from local health services. RESULTS: Two elevation waves of outpatient consultations were detected at weeks 19 and 26, that coincided with the periods of maximal detection of influenza and syncytial respiratory virus, respectively. The epidemics of respiratory syncytial virus coincided with the maximal number of hospital admissions for lower respiratory tract infections at week 27. There was no correlation between air pollution and the number of pediatric consultations. The lower ambient temperatures coincided with the higher detection of respiratory syncytial virus at week 28, moment in which the demand for consultations or hospital admissions was descending. CONCLUSIONS: There is a direct relationship between respiratory virus epidemics and the demand for pediatric consultations. There is also a minor influence of ambient temperature.

Acute Disease↗
PubMed1995

Endoscopy of the upper respiratory tract during treadmill exercise: a clinical study of 100 horses.

Endoscopy of the upper respiratory tract was performed in 100 horses during high speed treadmill exercise. Reasons for endoscopy were a history of an abnormal noise during exercise in 75 horses, poor performance in 17 horses and to evaluate the results of upper respiratory tract surgery in 8 horses. Of the 75 horses with a history of an abnormal noise during exercise the cause was determined in 67 (89%). Endoscopic abnormalities were detected at rest in 40 of these 75 horses (53%). In these 40 horses, a similar diagnosis as to the cause of the abnormal noise was made at rest and during exercise on the treadmill in 19 cases, while in the remaining 21 the endoscopic findings during exercise varied from that seen at rest. This included 3 horses in which a diagnosis was made at rest but no abnormalities were detected during exercise. Some of the findings during treadmill endoscopy included laryngeal dysfunction, grades 3, 4 and 5 (22 cases), dorsal displacement of the soft palate (20), epiglottic entrapment (8), epiglottic flutter (4), aryepiglottic fold flutter (4), pharyngeal collapse (3), arytenoiditis (3), vocal cord flutter (3), false nostril noise (2), pharyngeal lymphoid hyperplasia (2), soft palate haemorrhage (1) and positional arytenoid collapse (1). More than one abnormality was observed during exercise in 7 horses. A complete and correct diagnosis based on the resting endoscopy findings alone was made in 19 (25%) of these 75 cases. In the 17 horses examined because of poor performance, no abnormalities were detected during treadmill endoscopy that were not evident at rest.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

Memory associated with IgA in the porcine respiratory tract.

Pigs which had been immunised intraperitoneally with ovalbumin were subsequently challenged intratracheally with ovalbumin at intervals over a 200 day period. Intratracheal challenge 74 and 77 days after intraperitoneal priming resulted in a significant antigen-specific IgA response in respiratory tract secretion (RTS) on day 81. After a further 91 days, similar intratracheal challenge resulted in a lesser antigen specific IgA response in RTS. These trends were examined relative to antigen-specific IgA levels in serum and relative to antigen-specific IgG levels in serum and RTS. In addition, at the completion of the experiment the majority of anti-ovalbumin containing cells (AOCC) in the tracheal lamina propria were of the IgA class. Previously it has been shown that intratracheal challenge alone with ovalbumin had a negligible effect on AOCC in the trachea, and on specific antibody levels in respiratory tract secretion. The present findings suggest the existence of a memory mechanism operating in the porcine respiratory tract.

Animals↗
PubMed1999

Clinical and immunoregulatory effects of roxithromycin therapy for chronic respiratory tract infection.

The clinical and immunoregulatory effects of long-term macrolide antibiotic therapy for patients with chronic lower respiratory tract infections (CLRTI) were investigated. Clinical parameters and neutrophil chemotactic mediators in the epithelial lining fluid (ELF) of CLRTI patients (n = 10) were examined before and after 3 months oral administration of roxithromycin (RXM). The in vitro effects of RXM were also examined on the release of these mediators from alveolar macrophages (AM) and neutrophils. Arterial oxygen tension (p<0.05), vital capacity (VC) (p<0.001), %VC (p<0.05) and forced expiratory volume in one second (p<0.01) were improved after RXM treatment, but airway bacteria were not eradicated. Among the mediators, the levels of interleukin (IL)-8, neutrophil elastase (NE) and leukotriene B4 (LTB4) were higher in ELF than in plasma of CLRTI patients and they decreased after RXM treatment (n = 7, p<0.05 for each). RXM concentrations were significantly increased in the bronchoalveolar lavage cells of the treated patients. In in vitro experiments, RXM showed inhibitory effects on IL-8 release from AM and neutrophils. In conclusion, interleukin-8, neutrophil elastase and leukotriene B4 contribute to the neutrophilic inflammation in the airways of chronic lower respiratory tract infection patients and the clinical effects of roxithromycin may, in part, be attributable to the suppression of excess release of the chemotactic mediators from inflammatory cells.

Anti-Bacterial Agents↗
PubMed2002

Natural history of serum immunoglobulin concentrations in low birth weight infants and association with respiratory tract infections.

UNLABELLED: Infections are a significant cause of morbidity and mortality among low birth weight (LBW) infants. THE AIMS OF OUR STUDY WERE: (1) to investigate whether serum antibody concentrations in 62 LBW infants (1,500-2,500 g) were normalized by 1 year of life, and (2) to determine the clinical relevance of humoral immaturity in these children during the 1st year compared to 20 appropriate-for-gestational-age (AGA) term infants. At 1 year of life, immunoglobulin serum concentrations in LBW infants were comparable to those of the control group. The incidence of respiratory tract infections during the 1st year of life was not significantly different between LBW and AGA term infants. Interestingly, we demonstrated that LBW infants with a higher frequency of reported febrile upper respiratory tract infections had more elevated serum total IgG, IgG(1), IgG(3), total IgA, and IgA(1) concentrations. Thus, infants with a birth weight of 1,500-2,500 g do not appear to have an increased risk of respiratory tract infections compared to AGA term children during the 1st year of life. Furthermore, our data suggest that especially febrile infections induce higher serum immunoglobulin concentrations in LBW infants.

Birth Weight↗
PubMed1991

[A new respiratory tract pathogen].

Chlamydia pneumoniae strain TWAR, a newly described Chlamydia organism is a common cause of pneumonia and other acute respiratory tract infections. Most TWAR infections are mild or asymptomatic, but occasionally severe pneumonia in elderly patients or with on going chronic diseases has been observed. Population antibody prevalence has shown that TWAR infection is world-wide infection and an important health problem since under-developing countries where the high rate of child death is predominant, TWAR infections cause acute respiratory tract infection in children who are less than 5 yrs of age. Re-infection during life-time emphasizes the importance of Chlamydia pneumoniae.

Antibodies, Bacterial↗
PubMed2005

Diagnostic value of C reactive protein in infections of the lower respiratory tract: systematic review.

OBJECTIVES: To evaluate the diagnostic accuracy of C reactive protein in detecting radiologically proved pneumonia and to evaluate how well it can discriminate between bacterial and viral infections of the lower respiratory tract. DATA SOURCES: Medline and Embase (January 1966 to April 2004), with reference checking. STUDY SELECTION: We included articles comparing C reactive protein with a chest radiograph or with microbiological work-up as a reference test. Two authors independently assessed methodological items. RESULTS: None of the studies met all validity criteria. Six studies used an infiltrate on chest radiograph as reference test. Sensitivities ranged from 10% to 98%, specificities from 44% to 99%. For adults, the relation of C reactive protein with an infiltrate (in a subgroup analysis of five studies) showed an area under the curve of 0.80 (95% confidence interval 0.75 to 0.85). In 12 studies, the relation of C reactive protein with a bacterial aetiology of infection of the lower respiratory tract was studied. Sensitivities ranged from 8% to 99%, specificities from 27% to 95%. These data were epidemiologically and statistically heterogeneous, so overall outcomes could not be calculated. CONCLUSION: Testing for C reactive protein is neither sufficiently sensitive to rule out nor sufficiently specific to rule in an infiltrate on chest radiograph and bacterial aetiology of lower respiratory tract infection. The methodological quality of the diagnostic studies is generally poor. The evidence not consistently and sufficiently supports a wide introduction of C reactive protein as a rapid test to guide antibiotics prescription.

Area Under Curve↗
PubMedDate not supplied

Assessment of upper respiratory tract and ocular irritative effects of volatile chemicals in humans.

Accurate assessment of upper respiratory tract and ocular irritation is critical for identifying and remedying problems related to overexposure to volatile chemicals, as well as for establishing parameters of irritation useful for regulatory purposes. This article (a) describes the basic anatomy and physiology of the human upper respiratory tract and ocular mucosae, (b) discusses how airborne chemicals induce irritative sensations, and (c) reviews practical means employed for assessing such phenomena, including psychophysical (e.g., threshold and suprathreshold perceptual measures), physiological (e.g., cardiovascular responses), electrophysiological (e.g., event-related potentials), and imaging (e.g., magnetic resonance imaging) techniques. Although traditionally animal models have been used as the first step in assessing such irritation, they are not addressed here since (a) there are numerous reviews available on this topic and (b) many rodents and rabbits are obligate nose breathers whose nasal passages differ considerably from those of humans, potentially limiting generalization of animal-based data to humans. A major goal of this compendium is to inform the reader of procedures for assessing irritation in humans and to provide information of value in the continued interpretation and development of empirical databases upon which future reasoned regulatory health decisions can be made.

Air Pollutants, Occupational↗
PubMed2002

Concurrent serious bacterial infections in 2396 infants and children hospitalized with respiratory syncytial virus lower respiratory tract infections.

BACKGROUND: At Driscoll Children's Hospital (Corpus Christi, Tex), we observed that most infants and children hospitalized for treatment of respiratory syncytial virus (RSV) bronchiolitis and/or pneumonia received broad-spectrum intravenous antibiotics despite having typical RSV signs and symptoms and positive RSV-rapid-antigen tests on admission. Physicians were concerned about the possibility of concurrent serious bacterial infections, especially in infants younger than 3 months and in those with infiltrates present on the chest x-ray films. OBJECTIVE: To report the frequency of concurrent serious bacterial infections in infants and children hospitalized for treatment of RSV lower respiratory tract infections. METHODS: The medical records of 2396 infants and children admitted to Driscoll Children's Hospital with RSV bronchiolitis and/or pneumonia during 7 RSV seasons from July 1, 1991, through June 30, 1998, were reviewed. RESULTS: There were positive cultures obtained from initial sepsis/meningitis workups on admission in 39 infants and children (1.6%). Of these, 12 (31%) were positive blood cultures and 27 (69%) were positive urine cultures. There were no positive cerebrospinal fluid cultures. All of the positive blood cultures contained either Staphylococcus epidermidis, Staphylococcus warneri, or Bacillus species, which are common contaminants. None of the patients received a standard 10-day course of intravenous antibiotic therapy. All of the positive urine cultures were typical urinary tract pathogens. All of the patients were treated. CONCLUSIONS: Concurrent serious bacterial infections are rare in infants and children hospitalized with RSV lower respiratory tract infections and the empiric use of broad-spectrum intravenous antibiotics is unnecessary in children with typical signs and symptoms of RSV bronchiolitis.

Anti-Bacterial Agents↗