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At least 1,153 records · Page 64Linked to original sources
PubMed1977

Cryptococcosis, with emphasis on the significance of isolation of Cryptococcus neoformans from the respiratory tract.

Cryptococcus neoformans was isolated from 65 patients: 11 had meningitis, 11 had disseminated cryptococcosis without meningitis, and 43 had C neoformans isolated from the respiratory tract. Predisposing conditions and the diagnostic value of cultures from various sites and of the latex agglutination test on cerebrospinal fluid and serum are analyzed for patients with extrapulmonary disease. Nine patients had pleural effusions; the effusion was cultured in six and yielded C neoformans in four. None of 11 deaths among 43 patients with respiratory tract isolates could be attributed to cryptococosis. The 32 survivors were nor treated with antifungal agents. Twenty-six of 43 patients with respiratory isolates had various bronchopulmonary disorders, with chronic obstructive pulmonary diseases and asthma the most common (28 percent). Seven of 28 patients (25 percent) with roentgenographically detected lung lesions had carcinoma of the lung. Roentgenographic evidence of a lung lesion and C neoformans grown from the respiratory tract warrant a further search for carcinoma of the lung.

Adult↗
PubMed2004

Anatomical features of anti-viral immunity in the respiratory tract.

The mucosal surfaces of the lungs are a major portal of entry for virus infections and there are urgent needs for new vaccines that promote effective pulmonary immunity. However, we have only a rudimentary understanding of the requirements for effective cellular immunity in the respiratory tract. Recent studies have revealed that specialized cellular immune responses and lymphoid tissues are involved in the protection of distinct anatomical microenvironments of the respiratory tract, such as the large airways of the nose and the alveolar airspaces. This review discusses some of the anatomical features of anti-viral immunity in the respiratory tract including the role of local lymphoid tissues and the relationship between effector and memory T cells in the airways, the lung parenchyma, and lymphoid organs.

Animals↗
PubMed2001

Food allergy and the respiratory tract.

Previous studies have confirmed that IgE-mediated, food allergy-induced respiratory tract symptoms occur, typically accompanied by cutaneous or gastrointestinal symptoms. The possibility that respiratory tract symptoms are food allergy induced should be considered in patients who have a current or past history of one or more of the following: atopic dermatitis, wheezing (or experiencing anaphylactic symptoms) after ingesting a particular food or foods, and confirmed food allergy. Moreover, the work-up of food allergy in asthma should be considered in patients in whom asthma is poorly controlled despite persistent use of appropriate asthma medications. A definitive diagnosis of food allergy should be based on clinical history, appropriate laboratory testing, and, when indicated, well-controlled oral food challenges. Treatment is based on establishing a safe elimination diet and an emergency plan for managing reactions caused by accidental ingestion.

Australia↗
PubMed1994

Study on the children of Kaohsiung with acute viral infection of lower respiratory tract by direct immunofluorescence assay.

This study retrospectively reviewed those pediatric patients of acute lower respiratory tract infection with positive virus identification by direct immunofluorescence assay (Direct IF) from Jan, 1992 to Dec, 1993. One hundred and eighteen patients with 133 positive Direct IF results (107 cases with single virus identified, and 11 cases with more than one) were included. The sex ratio was 1.6:1 with males predominant; age, 22.1 (1 approximately 154.8) (months); duration of admission, 5.7 (1 approximately 69) (days); peripheral white blood cell count, 10,600 +/- 3,800/mm3; C-reactive protein, 17.0 (0 approximately 163.3) mu/ml; body temperature, 37.1 +/- 1.1 degrees C in those cases with single virus. The symptoms were cough 105 cases (98.1%), rhinorrhea 46 cases (43.0%), dyspnea and/or tachypnea 43 cases (40.2%) and diarrhea 15 cases (14.0%). The viruses identified were: Adenovirus (52 cases, 39.1%). Influenza B (45 cases, 33.8%), Parainfluenza 1 (28 cases, 20.1%), Parainfluenza 3 (19 cases 14.3%), Respiratory Syncytial virus (17 cases, 12.8%), and Influenza A (9 cases, 6.8%). The seasonal incidence rates were spring (49 cases, 36.8%), summer (46 cases, 34.6%), autumn (23 cases, 17.3%), and winter (15 cases, 11.3%). The results showed much similarity with others, except the commonest viral type (Adenovirus in this study; Respiratory Syncytial virus in others) and the seasonal incidence rate (higher in spring and summer in this study but not in others). In conclusion, most children with acute viral lower respiratory tract infection had an uneventful course and Direct IF is a reliable method for viral detection in that disease.

Acute Disease↗
PubMed1989

Histologic changes in the respiratory tract induced by inhalation of xenobiotics: physiologic adaptation or toxicity?

Toxicologists and pathologists are often faced with the dilemma of categorizing changes observed in the respiratory tract of laboratory animals as either "adaptive" or "toxic." However, it is often difficult to interpret the nature of a given change as either "adaptive" or "toxic." Certain lesions or changes in the respiratory tract are to be expected from the concentration of materials given or the experimental design of a study. Careful analysis suggests that some of these changes may be more properly described as adaptive rather than toxic within the context of a given study or situation. Tissue changes discussed in this paper include squamous metaplasia of laryngeal epithelium, goblet cell change in respiratory epithelium, macrophage accumulation within alveoli, and bronchiolization of alveolar epithelium. Examples provided show that some of these changes observed in inhalation studies are similar in severity but slightly increased in frequency over sham control animals. The introduction of exogenous material into the respiratory tract of laboratory animals in an experimental setting should be expected to result in certain changes. The challenge scientists must accept is to interpret these changes so that toxic events may be separated from adaptive changes. In order to meet this challenge, studies incorporating several species and novel technologies may have to be utilized.

Adaptation, Physiological↗
PubMed1992

Cilia in children with recurrent upper respiratory tract infections: ultrastructural observations.

We investigated the ultrastructure of nasal cilia in 27 children suffering from recurrent infections of the upper respiratory tract, during and after the onset of an acute respiratory infection, and after a convalescent period of 12 weeks. Our results demonstrated that in seven subjects after resolution of infection, the morphology of a large proportion of the cilia (32%) was not back to normal. These findings suggest a long-term residual effect of infection, or the inability to reestablish normal ciliary structure during the convalescent period in some subjects with recurrent upper respiratory tract infection.

Acute Disease↗
PubMed1991

[Clinical and pharmacokinetics studies of ceftriaxone upon 2g once daily administration in respiratory tract infections].

Clinical studies on ceftriaxone (CTRX) were conducted with 2 g once daily administration to respiratory tract infections. In addition, CTRX concentrations in serum, sputum and urine were determined. The results obtained are summarized as follows: 1. Clinical responses to CTRX in a total of 29 cases with respiratory tract infections were excellent in 7 cases, good in 13, fair in 8 and poor in 1 with a response rate of 69.0%. 2. CTRX concentrations in serum, sputum and urine (total and free body) were determined in 3 cases after intravenous drip infusion of 2g CTRX. Peak levels in sputum were 2.6 to 7.8 micrograms/ml, and CTRX maintained high sputum levels for 12 to 24 hours after administration.

Aged↗
PubMed1988

Mucosal immunology--with special reference to specific immune defence of the upper respiratory tract.

The mucosa of the upper respiratory tract is protected by a secretory immune system which is under complex immunoregulatory control. B cells with a potential for J-chain expression are initially stimulated in mucosa-associated lymphoid tissue (probably including the tonsils) and thereafter migrate through lymph and blood to glandular sites where they differentiate to immunoglobulin-producing immunocytes. Most locally produced immunoglobulin normally consists of dimeric IgA which is selectively transported through serous glandular cells by means of an epithelial receptor protein called the secretory component (SC). IgM is also subjected to SC-mediated transport. In patients with selective IgA deficiency, secretory IgA is lacking, but it may be satisfactorily replaced by protective secretory IgM. In other IgA-deficient patients, however, immunoregulatory compensation gives rise to a large number of IgD-producing cells in respiratory mucosae. IgD cannot act as a secretory antibody and these patients are prone to have recurrent infections. There are thus large individual variations in the secretory immune system, which in the future hopefully may be subjected to regulatory manipulation.

B-Lymphocytes↗
PubMed1999

Chlamydia trachomatis (mouse pneumonitis strain) induces cardiovascular pathology following respiratory tract infection.

Chlamydia, especially Chlamydia pneumoniae, infection is closely associated with human cardiovascular diseases. Thus far, however, few experimental studies have been carried out to investigate whether natural C. trachomatis infection can induce cardiovascular pathological changes. In this article, we report that pulmonary infection with C. trachomatis mouse pneumonitis strain (MoPn) can induce myocardial and perivascular inflammation and fibrosis in C57BL/6 mice. The pulmonary MoPn infection appeared to be disseminated systemically, because chlamydial antigens were readily detectable in multiple organs including the cardiovascular tissues. In addition, gamma interferon gene knockout mice with a C57BL/6 genetic background showed significant endocarditis and pancarditis characterized by vegetation in aortic valves, interstitial and pericardial inflammatory cellular infiltration, and growth of the organisms in the heart following respiratory tract MoPn infection. The results indicate that C. trachomatis can induce cardiovascular diseases following respiratory tract infection and suggest that murine MoPn respiratory tract infection may be a useful experimental model for investigating cardiovascular diseases caused by chlamydial infection.

Animals↗
PubMed2001

Principles of appropriate antibiotic use for treatment of acute respiratory tract infections in adults: background, specific aims, and methods.

The need to decrease excess antibiotic use in ambulatory practice has been fueled by the epidemic increase in antibiotic-resistant Streptococcus pneumoniae. The majority of antibiotics prescribed to adults in ambulatory practice in the United States are for acute sinusitis, acute pharyngitis, acute bronchitis, and nonspecific upper respiratory tract infections (including the common cold). For each of these conditions--especially colds, nonspecific upper respiratory tract infections, and acute bronchitis (for which routine antibiotic treatment is not recommended)--a large proportion of the antibiotics prescribed are unlikely to provide clinical benefit to patients. Because decreasing community use of antibiotics is an important strategy for combating the increase in community-acquired antibiotic-resistant infections, the Centers for Disease Control and Prevention convened a panel of physicians representing the disciplines of internal medicine, family medicine, emergency medicine, and infectious diseases to develop a series of "Principles of Appropriate Antibiotic Use for Treatment of Acute Respiratory Tract Infections in Adults." These principles provide evidence-based recommendations for evaluation and treatment of adults with acute respiratory illnesses.This paper describes the background and specific aims of and methods used to develop these principles. The goal of the principles is to provide clinicians with practical strategies for limiting antibiotic use to the patients who are most likely to benefit from it. These principles should be used in conjunction with effective patient educational campaigns and enhancements to the health care delivery system that facilitate nonantibiotic treatment of the conditions in question.

Acute Disease↗
PubMed1988

Respiratory tract infections increase susceptibility to neurogenic inflammation in the rat trachea.

This study reveals that respiratory tract infections make the tracheal mucosa of rats more susceptible to neurogenic inflammation, which is a type of inflammation mediated by neuropeptides released from sensory nerves. Neurogenic inflammation was produced in the tracheas of 2 groups of Long-Evans rats by electrical stimulation of the vagus nerve (5 V, 1 ms, 20 Hz for 5 min) or by an injection of capsaicin (15 to 200 micrograms/kg i.v.) or substance P (0.05 to 5.0 micrograms/kg i.v.). Rats of one group were pathogen-free; the others had serologic evidence of naturally occurring airway infections caused by Sendai virus, coronavirus, and Mycoplasma pulmonis. The stimuli produced neurogenic inflammation in both groups of rats, but the magnitude of this inflammation was much greater in the infected rats. The susceptibility of the infected rats to neurogenic inflammation was manifested by a 2.0 to 3.1 times larger increase in vascular permeability to Monastral blue, 5 times larger increase in number of neutrophils adhering to the endothelium of venules, and conspicuous morphologic changes in the tracheal epithelium. When pathogen-free rats acquired respiratory tract infections, they too became susceptible to neurogenic inflammation. Other experiments showed that infection by Sendai virus was essential for the change, although infection by M. pulmonis or coronavirus may also be necessary. The susceptibility to neurogenic inflammation outlasted the transient pathologic changes caused in the airway mucosa by the viral infections and may have been permanent.

Animals↗
PubMed2003

Epidemiology and seasonality of respiratory tract virus infections in the tropics.

Acute viral respiratory tract infections are a significant cause of morbidity worldwide. Information on the epidemiology and seasonality of these infections is important in planning vaccination and treatment strategies. In temperate climes, there are distinct seasonal peaks in the winter months. This paper reviews the seasonal trends of respiratory viral infections in the tropics. Despite the absence of a winter season, consistent seasons of infection, albeit less distinct, have been observed. With few exceptions, respiratory syncytial virus and influenza infections have been observed mainly during the rainy seasons in Asian, African and South American countries.

Age Distribution↗
PubMed1992

[Bacterial adherence to the alveolar and respiratory tract system].

Bacterial adherence to the alveolar and respiratory tract system was broadly divided into specific and non-specific adhesion, and effects such as aging were investigated. In specific adhesion, various types of lectin that specifically bind to oligosaccarids as bacterial receptors were used, and lectin specific sugers map of the alveolar and respiratory system were prepared. However, no quantitative difference in oligosaccarids distribution was noted between elderly and young subjects. Meanwhile, in nonspecific adhesion, a study on K. pneumonia infection in mice revealed a pattern of glycocalyx production by the bacteria and their adhesion to the alveolar wall. Clinically, in cases of chronic respiratory infection, a pattern of production of and assembly around glycocalices by P. aeruginosa was observed (biofilm). In vitro tests showed that bacteria in the biofilm are resistant to antibacterial drugs. In the elderly, many factors match the conditions that facilitate the production of glycocalices by bacteria, and many infections of the respiratory organs in the elderly are attributed to nonspecific bacteria adhesion. Infections are thought to become intractable once they extend into biofilm.

Aged↗
PubMed1990

Overview of experience with ofloxacin in respiratory tract infection.

Ofloxacin is highly active against common respiratory pathogens including Haemophilus influenzae and Branhamella catarrhalis and has clinically applicable activity against Streptococcus pneumoniae, Staphylococcus aureus and Pseudomonas aeruginosa. Sputum, lung tissue and bronchial mucosal concentrations of ofloxacin equal or, in most cases significantly exceed the MICs of such pathogens. These in vitro attributes are reflected in the results of the worldwide ofloxacin clinical trial program which achieved overall response rates of 98% in lower respiratory tract infections, 83% in pneumonias and 87% to 95%, in open and comparative studies respectively, in patients with acute exacerbations of chronic bronchitis (CB). Overall bacterial eradication rates ranged from 70% for pneumococci and 84.5% for B. catarrhalis to 88.5% for H. influenzae. In lower respiratory infection ofloxacin gave equal or superior clinical results to amoxycillin or erythromycin therapy together with an overall bacterial eradication rate of 100%. Clinical results comparable with standard agents were also obtained in pneumonia, cure rates ranging from 77-89% at various dosages. Eradication rates proved greatest for H. influenzae (92%) and were satisfactory for Klebsiella spp. (80%), although less so for pneumococci (73%). Bacteriological eradication rates in acute exacerbations of chronic bronchitis ranged from 68% for pneumococcal infections, to 85% in B. catarrhalis and 94% in H. influenzae infections. Ofloxacin compared favourably with pivampicillin, co-trimoxazole and doxycycline clinically. A daily oral ofloxacin dose of 400 mg produced a good clinical response in 92% of patients or more. The available clinical data therefore substantially confirm the claim of ofloxacin to offer an effective alternative in many forms of acute bacterial respiratory infection, especially where H. influenzae and B. catarrhalis are involved.

Bronchitis↗
PubMed1988

Depression after each respiratory tract infection in an adolescent girl.

Recurrent episodes of depression accompanied by mild hypersomnia after each respiratory tract infection in an adolescent girl, 10 years old at the first onset, are described. Each episode lasted about 1 week, and she had 11 such episodes up to the age of 14 years, when lithium was prescribed. While on lithium, she suffered three times from febrile and once from afebrile upper respiratory tract infection, but these episodes were not followed by depression or hypersomnia.

Adolescent↗
PubMed1987

Biochemical basis of physical properties of respiratory tract secretions.

The physical properties of respiratory tract secretion (RTS) play a prominent rôle in the non-specific defence mechanisms of the lung. Viscosity and elasticity, that is flow and deformation, are only two of the physical properties of RTS. Spinability, pourability, adhesiveness and tackiness are starting to be recognised as physical properties of RTS and its is likely that they may be relevant in the pathogenesis of airways obstruction. RTS is a gel, which consists of a cross-linked polymer network dispersed in a liquid solvent. The polymeric structure of the epithelial glycoprotein can be explained in terms of covalent (disulphide) linkages and/or physical entanglement between glycoproteins subunits. Other constituents of RTS such as proteins, lipids, ions and water can influence the physical properties of RTS.

Chemical Phenomena↗