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Yeast-like fungi isolated in students

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The occurrence of yeast-like fungi in the most important infection portals of the respiratory system in 200 randomly chosen students of biology and veterinary medicine was examined. The students come into direct contact with plants and animals that may be colonised by fungi belonging to various systematic groups. nine species of yeast-like fungi, including 7 species determined in the biologists, were recorded in the subjects. Candida tropicalisand C.albicanswere the most frequently isolated fungi. The greatest number of fungi was isolated from the oral cavity (124 isolates), fewer from the throat (79 isolates), and the smallest number from the nose (8 isolates). Fungi occurred more frequently in autumn and slightly less frequently in spring, and were isolated more frequently from women than from men.
This review article presents fundamental mechanisms of the local mucosal immunity in selected regions of the respiratory tract in healthy birds and in some pathological conditions. The respiratory system, whose mucosa come into direct contact with microorganisms contaminating inhaled air, has some associated structures, such as Harderian gland (HG), conjunctive-associated lymphoid tissue (CALT) and paranasal glands (PG), whose participation in local mechanisms of the mucosal immunity has been corroborated by numerous scientific studies. The nasal mucosa, with structured clusters of lymphoid tissue (NALT – nasal-associated lymphoid tissue) is the first to come into contact with microorganisms which contaminate inhaled air. Lymphoid nodules, made up of B cells with frequently developed germinal centres (GC), surrounded by a coat of CD4+ cells, are the major NALT structures in chickens, whereas CD8+ cells are situated in the epithelium and in the lamina propria of the nasal cavity mucosa. Studies into respiratory system infections (e.g. Mycoplasma gallisepticum) have shown the reactivity of the tracheal mucosa to infection, despite a lack of essential lymphoid tissue. Bronchus-associated lymphoid tissue (BALT) takes part in bronchial immune processes and its structure, topography and ability to perform defensive function in birds is largely age-dependent. Mature BALT is covered by a delicate layer of epithelial cells, called follicle-associated epithelium (FAE). Germinal centres (GC), surrounded by CD4+ cells are developed in most mature BALT nodules, while CD8+ lymphocytes are dispersed among lymphoid nodules and in the epithelium, and they are rarely present in GC. Macrophages make up the first line of defence mechanisms through which the host rapidly responds to microorganisms and their products in the respiratory mucosal system. Another very important element are polymorphonuclear cells, with heterophils being the most important of them. Phagocytic cells obtained from lung lavages in birds are referred to as FARM (free avian respiratory macrophages). Their number in chickens and turkeys is estimated to be 20 times lower than that in mice and rats, which indicates a deficit in the first-line of defence in the birds’ respiratory system. There are numerous B cells and antibody secreting cells (ASC) present throughout the respiratory system in birds. Their role comes down to perform antigen-specific protection by producing antibodies (IgM, IgY or IgA class) as a result of contact with pathogenic factors.
Severe Acute Respiratory Syndrome (SARS) is a dangerous respiratory system infection leading to a grave respiratory distress. The aim of the study is presentation of up-to-date information concerning Severe Acute Respiratory Distress Syndrome. SARS epidemics began in November 2002 in Chinese province Guangdong. In May 2003 the total number of SARS cases was estimated at 7761 and 623 deaths were reported. To the group of increased risk there belong people traveling and remaining in the regions of SARS occurrence as well as people in close contact with a sick person. There was noted high effectiveness of worldwide prophylactic actions, which have currently lead to controlling the outbreak of the epidemic.
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Pulmonary function between 40 and 80 years of age

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Spirometry is the most frequently performed lung function test. To determine a normal range of spirometry results, reference formulas are used. Predicted values play an important role in establishing whether the volumes measured in an individual fall within a range to be expected in a healthy person of the same gender, height, and age. Such standards enable to assess the development of the respiratory system in the youth, the early recognition of the influence of a disease on the respiratory system and the influence of environmental factors on lung function. The objective of the present study was to estimate lung function prediction equations and to identify appropriate normal reference values for the Lublin Region local population of adults. We addressed the issue by analyzing the data from a lung function screening program conducted in the Lublin Region of Poland. Pulmonary function of adults aged 40-80 years was assessed from the measurements of forced vital capacity (FVC) and forced expired volume in the first second (FEV1) in 136 adults. Reference values of FVC and FEV1 for females and males were calculated by linear multiple regressions with age and height used as predictors. Different equations were compared to show their reliability when applied to the local population. The results were as follows. In females, the mean FEV1 was 2.856 ±0.534 (L) (113.7 ±14.3%) and the mean FVC was 3.517 ±0.662 (L) (118.5 ±14.1%), in males, 3.913 ±0.773 (L) (110.9 ±15.1%), 4.922 ±0.941 (L) (112.1 ±14.1%), respectively. The estimated prediction equations were: for the FVC - for females - FVC (L) = 0.0528 (height) - 0.0262 (age) - 3.676 and for males - FVC = 0.0756 (height) - 0.0649 (age) - 4.904; and for the FEV1 - for females - FEV1 (L) = 0.0378 (height) - 0.0282 (age) - 1.799 and for males - FEV1 (L) = 0.0553 (height) - 0.0553 (age) - 2.874. Units are years for age and centimeters for height. In conclusion, the analysis of the lung function data showed that there were significant difficulties in determining the appropriate reference values of FEV1 and FVC. The predicted FEV1 and FVC values derived from equations based on the ECSC (1) reference populations are considerably lower than those calculated in the present study, re-emphasizing the need to be cautious when applying the ECSC reference values for the local Lublin population. There seems to be a need for a constant refinement of spirometric standards.
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Pharmacological impact on loop gain properties to prevent irregular breathing

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Theory predicts respiratory instabilities at elevated system loop gain (G), determined by such factors as ventilatory CO2 sensitivity, set-point PCO2, and metabolic rate. In anesthetized rabbits, the effects on G of carbonic anhydrase (CA) inhibitors and of different sodium/proton exchanger type 3 (NHE3) inhibitors were studied. Acetazolamide significantly reduced G by 42.0 ± 9.3% and methazolamide by 35.0 ± 9.5% (each n = 7, P<0.01). Irrespective of the substance, NHE3 inhibition reduced G by 33.0 ± 7.8% (n = 10, P<0.01) at 35.5 ± 1.6 mmHg PaCO2 (mean ±SE), but not at lower arterial CO2 levels (n=5). Since high baseline PCO2 coincides with elevated brainstem NHE3 mRNA expression, this may also account for a higher risk of sleep apnea (or even occurrence of sudden infant death). Therefore, NHE3 inhibitors may gain similar therapeutic importance in the treatment of irregular breathing as CA inhibitors. Generally, effective treatment should aim at a low system loop gain, by reducing respiratory chemosensitivity, improving blood gases and preventing low metabolic rates.
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The aging corotid body

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The respiratory system is subject to the aging process, which could limit its responsiveness to hyperventilatory stimuli. Attenuation of the ventilatory response to hypoxia in old age is, as yet, an unresolved issue. Such attenuation may be germane for the pathogenesis of respiratory disorders developing more often in elderly subjects. The aim of this study was to determine the potential adverse effects of age on the morphology and function of carotid bodies. Morphology was studied at the level of electron microscopy on carotid bodies dissected from adult young (3 months) and old (>2 years) rats and function by comparing the hypoxic ventilatory response in populations of young (mean age 24 years) and old (mean age 71 years) female subjects. The human protocol consisted of a progressive hypoxia test, based on a rebreathing technique in a closed system. The hypoxic ventilatory response was evaluated from the slopes of minute ventilation on arterial oxygen saturation. The results of the morphological study showed degenerative changes developing with age in the ultrastructure of carotid bodies. On the other side, respiratory responses to hypoxia in old women were well preserved and were no less than those in young women. Therefore, a discrepancy appeared between the morphological and functional aspects. These findings suggest development of compensatory mechanisms in brain respiratory areas which maintain primary defensive reflexes, such as the hyperventilation of hypoxia.
Several lines of evidence suggest that physical exercise not only influences the development of muscles, cardiovascular and respiratory systems, but also exerts a significant influence on the central nervous system. We examined the influence of strength and endurance training on cognitive performance in 33 healthy elderly volunteers (women, mean age 63.5 ±4.5 yr) over a 3-month period of supervised training program. A control group consisted of 8 age-matched (mean age 66.3 ±4.6) healthy volunteers who did not participate in any exercise training program. To evaluate the cognitive performance in our subjects we used two tests: face/name association test and Stroop test. The tests were applied shortly before and immediately after the training program. In the experimental group, a significant improvement in the association test performance, on average, from 71.6 ±7.3% to 79.7 ±7.2% (P<0.0001) was observed over the 3-month training period. There were no changes in the Stroop test results over the same time. Likewise, there were no changes in the control groups. Our data demonstrate that the training regime that is strictly followed over a relatively short period of time may improve the performance in associative memory tasks in elderly subjects. The study supports the notion that physical exercise influences cognitive performance and extend this notion to be valid for healthy elderly subjects.
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The natural history of respiratory system function

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Lung growth starts in the first year of life. Between 20-30 years of age, man achieves the maximum FEV1. Some years later, maximum FVC is achieved. After the phase of a dynamic increase, lung function stabilizes for a while. Thereafter, it starts declining slowly in some individuals or increasing in others. The third and last phase of lung function changes during a lifetime begins between 40-45 years of life. The FEV1 and some years later also FVC diminish with a varied speed during this period. Changes in FVE1 and FVC in the third phase are slower at the beginning and accelerate in the six or seventh decade of life. There are some differences between males and females concerning the lung function profile. Female lung function starts decreasing earlier than that in male individuals. There are also pronounced interindividual differences in lung function among individuals of a similar age and body height.
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