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At least 19 recordsLinked to original sources
PubMed1992

Immunohistochemistry with keratin monoclonal antibodies in canine tissues: urogenital tract, respiratory tract, (neuro-)endocrine tissues, choroid plexus and spinal cord.

Twelve oligo- or monospecific monoclonal antibodies (MoAbs) directed against human keratin types were used in an immunohistochemical study of the canine male and female urogenital tract, the respiratory tract, the adrenal gland, the (para-)thyroid gland, the choroid plexus and the spinal cord. The keratin MoAbs showed differences in staining patterns in the various epithelial tissues and the diverse epithelial cells. The kidney was characterized by a complex keratin staining pattern and the canine urothelium showed regional differences in keratin staining. Also in the female genital tract different keratin staining patterns were observed. Testicular and adrenal gland cells did not react with any of the keratin MoAbs. The keratin staining patterns in the various canine tissues showed, in addition to similarities, also distinct differences when compared to the staining patterns in corresponding tissues of other species, e.g. of man. These staining dissimilarities indicate that the reactivity patterns of the keratin MoAbs with restricted keratin immunoreactivity can not be always extrapolated from one species to another. Nevertheless, MoAbs directed against human keratin proteins can apparently be used to differentiate between various types of canine epithelia or epithelial compartments.

Animals↗
PubMed1982

Selective infection of lower respiratory tract by respiratory viruses in children with recurrent respiratory tract infections.

Thirty preschool children presenting with recurrent respiratory infections and their unaffected siblings were observed prospectively for a year. The index children experienced more episodes of acute respiratory infection than their siblings. Respiratory viruses were the major cause of respiratory infections. The index children had lower respiratory tract disease, predominantly wheeze, during 34% of proved respiratory virus infections compared with 11% of such infections experienced by the control children (p less than 0.02). Atopic children had an increased tendency to wheeze that did not reach significance, but atopy was not associated with increased susceptibility to respiratory infections.

Adenoviridae↗
PubMed1991

Effect of selective decontamination of the digestive tract on respiratory tract infections and mortality in the intensive care unit.

To assess the effect of selective decontamination of the digestive tract on respiratory tract infections and survival of patients treated in an intensive care unit, we carried out a meta-analysis of clinical studies comparing patients treated with selective decontamination with untreated controls. From eleven trials (1489 patients), differences between observed and expected respiratory tract infections and mortality were compared, and odds ratios (ORs) calculated. Analysis was done according to study design. With respect to the risk for respiratory tract infections, the studies with historical controls and the randomised trials showed a protective effect of selective decontamination. Historical control studies yielded an OR of 0.21 (95% confidence limits [CL] 0.15 to 0.29, p less than 0.05) and randomised trials an OR of 0.12 (95% CL 0.08 to 0.19, p less than 0.05). By contrast, the mortality benefit was less clear. Studies with historical controls and randomised trials showed that mortality was not significantly different between treatment and control patients. The evidence from these studies is at best consistent with a very limited effect of selective decontamination of the digestive tract on survival of patients in the intensive care unit, despite a clear preventive effect on the occurrence of respiratory tract infections.

Anti-Bacterial Agents↗
PubMed1975

Aerosol deposition in the dog respiratory tract.

Respiratory tract deposition of monodisperse aerosols have been measured in the dog, both in vivo and in excised lungs. Three particle sizes, 0.35, 0.50 and 1.0 micron, were used, with respiratory frequencies from 8 to 25 respirations/min and tidal volumes from 100 to 600 ml. The deposition fractions measured were compared with deposition fractions for one normal human subject using the same aerosols. In vivo deposition fractions for the dog were greater than those for man at comparable conditions, and greater than those for the excised lungs at the same conditions. Although sites of deposition were not directly measured, some conclusions about the appropriateness of animal aerosol toxicity studies for assessing human risk are presented. The hypothesis of geometric similarity of mammalian lungs is examine for dog and man.

Aerosols↗
PubMed2005

Growth of respiratory syncytial virus in primary epithelial cells from the human respiratory tract.

Respiratory syncytial virus (RSV) is the most important cause of lower respiratory tract disease in infants and children. To study RSV replication, we have developed an in vitro model of human nasopharyngeal mucosa, human airway epithelium (HAE). RSV grows to moderate titers in HAE, though they are significantly lower than those in a continuous epithelial cell line, HEp-2. In HAE, RSV spreads over time to form focal collections of infected cells causing minimal cytopathic effect. Unlike HEp-2 cells, in which wild-type and live-attenuated vaccine candidate viruses grow equally well, the vaccine candidates exhibit growth in HAE that parallels their level of attenuation in children.

Cells, Cultured↗
PubMed1987

Low potency of Ca antagonists in smooth muscle from different levels of the respiratory tract.

Respiratory smooth muscle at different levels of the respiratory tract was isolated from rabbit, rat and guinea-pig and incubated with the Ca antagonists, verapamil, D-600, felodipine, and nifedipine. There was no effect of the Ca antagonists when added on top of an already developed contraction. When added before the contractile agent at high concentrations (10-100 microM) the Ca antagonists reduced the contractions. Lanthanum (2 mM) was considerably more effective to prevent contractions than the Ca antagonists. Preparations from the trachea and bronchus responded in all animals, whereas the third generation bronchus from rat and guinea-pig failed to contract and that from rabbit showed very weak contractions. The failure to contract was not specific for the agonist, as depolarization with isotonic potassium solution (124 mM) did not evoke contractions either. Microscopic investigation showed well-developed smooth muscle in the trachea and main bronchus of the rat, whereas the muscle of the third generation bronchus was inhomogenous with scattered groups of muscle cells.

Animals↗
PubMed1997

Dosing of amoxicillin/clavulanate given every 12 hours is as effective as dosing every 8 hours for treatment of lower respiratory tract infection. Lower Respiratory Tract Infection Collaborative Study Group.

In this double-blind study, 557 patients with lower respiratory tract infection were randomly assigned to receive amoxicillin/clavulanate orally either every 12 hours (875/125 mg) or every 8 hours (500/125 mg) for 7-15 days. For the 455 patients evaluable for clinical efficacy at the end of therapy, clinical success was similar in the two groups: 93% and 94% in the 12-hour and 8-hour groups, respectively (P = .42). Bacteriologic success at the end of therapy was also comparable: 97% and 91% in the 12-hour and 8-hour groups, respectively (P = .86). The occurrence of adverse events related to treatment was similar for the two groups, but fewer patients in the 12-hour group reported moderate or severe diarrhea. Amoxicillin/clavulanate (875/125 mg) given every 12 hours is as effective and safe as every-8-hours administration of the combination (500/125 mg) for the treatment of lower respiratory tract infection.

Adolescent↗
PubMedDate not supplied

An overview: evaluation of cefonicid in infections of the urinary tract, lower respiratory tract, and skin and soft tissue.

Infections of the urinary and lower respiratory tracts and of skin and soft tissue constitute a large proportion of infections requiring antimicrobial therapy. For many antimicrobial agents, one dose will cure lower urinary tract infection. In contrast, relapse of upper tract infection is common even after two weeks of treatment. In comparing the efficacy of antimicrobial agents in urinary infection, it is critical that patients assigned to different agents be equivalent. The questions about cefonicid in urinary infection that must be addressed concern (1) adverse effects and tolerability, (2) cost, and (3) rationale for the use of a parenteral preparation in uncomplicated urinary infection. In lower respiratory tract infections, therapeutic efficacy is difficult to evaluate primarily because of the difficulty in determining the causative role of the organisms isolated from sputum. The inclusion of information from gram-stained preparations reduces the diagnostic error. As far as cefonicid in treatment of pneumonia is concerned, the high serum protein binding reported and the relatively high minimal inhibitory concentrations for gram-positive cocci must be addressed. In skin and soft-tissue infections, therapeutic efficacy is difficult to evaluate because of the lack of isolates and the self-limited nature of many cutaneous infections.

Bacterial Infections↗
PubMed1994

Epidemiology and pharmacoeconomic issues relating to acute respiratory tract infections and acute uncomplicated infections of the urinary tract.

Respiratory and urinary tract bacterial infections are among the most frequently encountered conditions in clinical medicine. Driven by the increasing incidence of antimicrobial resistance and treatment failures in these conditions, newer, and unfortunately more costly, alternatives are constantly being sought. As expenditures on healthcare are currently under greater levels of scrutiny than ever before, the economic aspects of drug therapy have become an important area of inquiry. Cost-effective drug therapy depends on several factors, of which initial drug cost is only one. Clearly, drug efficacy, duration of therapy and dose regimen, diagnostic strategies, route of drug administration, microbial drug resistance and patient compliance all directly impact on cost-effectiveness evaluations. However, to avoid merely shifting costs, true evaluation of cost-benefit must take indirect economic factors such as loss of patient (and parental) income, loss of productivity, opportunity costs, and patient discomfort/suffering into account. In this article, these issues are discussed and illustrated using common respiratory and urinary tract bacterial infections as a model.

Anti-Bacterial Agents↗
PubMed1992

In-vitro activity of cefpirome against isolates from patients with urinary tract, lower respiratory tract and wound infections.

The in-vitro activity of cefpirome, a new injectable cephalosporin, was compared with that of several other antibiotics against bacterial isolates from hospitalized patients with lower respiratory tract infections, urinary tract infections and wound infections. Minimum inhibitory concentrations were determined for 874 strains against 16 antibiotics using a microtitration technique. Cefpirome showed a very broad spectrum of activity against most pathogens tested. The spectrum included organisms such as Staphylococcus spp., enterococci, Enterobacter spp., and Pseudomonas spp. which are frequently resistant to third generation cephalosporins.

Anti-Bacterial Agents↗
PubMed2000

Somatizing disorders affecting the respiratory tract.

Respiratory disease in childhood is common but not all children presenting to the paediatrician have an underlying organic cause for their symptoms. This article reviews the spectrum of non-organic somatization disorders that might be encountered and advises about the diagnosis and treatment of habit cough, laryngeal dysfunction and hyperventilation.

Child↗
PubMed2002

Update on pneumococcal infections of the respiratory tract.

Respiratory illnesses are the leading reason for seeking medical care here in the United States. Streptococcus pneumoniae is the most common bacterial pathogen causing acute otitis media (AOM), sinusitis, and community-acquired pneumonia in both the pediatric and adult populations. The continued development of antibiotic resistance to an increasing number of different antibiotic classes by this organism has made the treatment of some of these infections more difficult. Recently, a heptavalent pneumococcal conjugate vaccine was approved for infants and toddlers, beginning at 2 months of age. Widespread implementation of this vaccine in the childhood population may have a significant impact on the amount of systemic disease seen with this organism.

Adult↗
PubMed2024

Intranasal neomycin evokes broad-spectrum antiviral immunity in the upper respiratory tract.

Respiratory virus infections in humans cause a broad-spectrum of diseases that result in substantial morbidity and mortality annually worldwide. To reduce the global burden of respiratory viral diseases, preventative and therapeutic interventions that are accessible and effective are urgently needed, especially in countries that are disproportionately affected. Repurposing generic medicine has the potential to bring new treatments for infectious diseases to patients efficiently and equitably. In this study, we found that intranasal delivery of neomycin, a generic aminoglycoside antibiotic, induces the expression of interferon-stimulated genes (ISGs) in the nasal mucosa that is independent of the commensal microbiota. Prophylactic or therapeutic administration of neomycin provided significant protection against upper respiratory infection and lethal disease in a mouse model of COVID-19. Furthermore, neomycin treatment protected Mx1 congenic mice from upper and lower respiratory infections with a highly virulent strain of influenza A virus. In Syrian hamsters, neomycin treatment potently mitigated contact transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In healthy humans, intranasal application of neomycin-containing Neosporin ointment was well tolerated and effective at inducing ISG expression in the nose in a subset of participants. These findings suggest that neomycin has the potential to be harnessed as a host-directed antiviral strategy for the prevention and treatment of respiratory viral infections.

Animals↗
PubMed1993

[Study of bacterial flora in the stomach and the upper and lower respiratory tracts--the mechanism of lower respiratory tract infection].

To evaluate the mechanism of lower respiratory tract infection in the hospital, gastric juice, throat secretions, secretions in tracheal cannulae or tubes and aspirated sputum were cultured simultaneously in seven patients with tracheostomy and seven patients with tracheal intubation. Thirty-six strains of bacteria were isolated from gastric juice and only 22.2% of them were the same bacteria as those in the throat secretions. This suggested that there was little correlation between gastric and oropharyngeal flora. The bacteria isolated from throat secretions and aspirated sputum showed 38.5% coincidence in tracheostomized patients and 80% coincidence in intubated patients. In addition, the rate of agreement was 33.3% in tracheostomized patients and 88.9% in intubated patients between throat secretions and tracheal cannulae or tubes. These findings suggested that the correlation of bacterial flora between the upper and lower respiratory tracts was high in intubated patients and low in tracheostomized patients. Identical bacteria in the stomach and the upper and lower respiratory tracts (which may cause nosocomial infection) were isolated in only four of the 14 patients. It has been suggested that bacterial flora in the lower respiratory tract are transmitted from the stomach to the oropharynx and then cause lower respiratory tract infection in hospital. However, our study suggested that this was not a common pathogenic mechanism.

Aged↗
PubMed2005

Intravenous immunoglobulin replacement prevents severe and lower respiratory tract infections, but not upper respiratory tract and non-respiratory infections in common variable immune deficiency.

BACKGROUND: Although the dose of 400 mg/kg body weight intravenous immunoglobulins (IVIG) every 3-4 weeks is now standard for treating patients with common variable immune deficiency, studies demonstrating its long-term benefits over low 200 mg/kg dose and its effects on infectious subsets (upper vs lower respiratory vs non-respiratory infections) are rare. METHODS: All patients from a single center with the diagnosis of common variable immune deficiency and whose clinical chart was available during three successive therapeutic periods [a pre-IVIG replacement period, a low-dose (200 mg/kg every 3 weeks) and a standard-dose replacement period (400 mg/kg every 3 weeks)] were screened retrospectively. RESULTS: Seven patients followed up for a total of 116 patient-years over the three defined periods of observation were recruited. When compared with low-dose therapy, standard-dose intravenous immunoglobulin therapy raised trough IgG levels from 4.3 to 6.5 g/l and significantly decreased the overall frequency of infections, with marked effects on lower respiratory tract and severe infection number. In contrast, non-respiratory and upper respiratory infections were, in comparison, resistant to therapy. CONCLUSIONS: Overall, these data support the use of standard-dose 400 mg/kg intravenous immunoglobulin therapy, despite the high cost, to raise trough IgG levels to 5-7 g/l, but underlines that some categories of infectious events (non-respiratory, upper respiratory) may need parallel surgical or pharmacological approaches to be optimally prevented or treated.

Adult↗
PubMed2002

Respiratory syncytial virus infection suppresses lung CD8+ T-cell effector activity and peripheral CD8+ T-cell memory in the respiratory tract.

Respiratory syncytial virus (RSV) is a major cause of morbidity from respiratory infection in infants, young children and the elderly. No effective vaccine against RSV is currently available and studies of the natural history of RSV infection suggest repeated infections with antigenically related virus strains are common throughout an individual's lifetime. We have studied the CD8+ T-cell response during experimental murine RSV infection and found that RSV inhibits the expression of effector activity by activated RSV-specific CD8+ T cells infiltrating the lung parenchyma and the development of pulmonary CD8+ T-cell memory by interfering with TCR-mediated signaling. These data suggest a possible mechanism to explain the limited duration of protective immunity in RSV infection.

Animals↗