Detection of bronchial breathing caused by pneumonia.

The classic auscultation with stethoscope is the established clinical method for the detection of lung diseases. The interpretation of the sounds depends on the experience of the investigating physician. Therefore, a new computer-based method has been developed to classify breath sounds from digital lung sound recordings. Lung sounds of 11 patients with one-sided pneumonia and bronchial breathing were recorded on both the pneumonia side and on contralateral healthy side simultaneously using two microphones. The spectral power for the 300-600 Hz frequency band was computed for four respiratory cycles and normalized. For each breath, the ratio R between the time-segments (duration = 0.1 s) with the highest inspiratory and highest expiratory flow was calculated and averaged. We found significant differences in R between the pneumonia side (R = 1.4 +/- 1.3) and the healthy side (R = 0.5 +/- 0.5; p = 0.003 Wilcoxon-test) of lung. In 218 healthy volunteers we found R = 0.3 +/- 0.2 as a reference-value. The differences of ratio R (delta R) between the pneumonia side and the healthy side (delta R = 1.0 +/- 0.9) were significantly higher compared to follow-up studies after recovery (delta R = 0.0 +/- 0.1, p = 0.005 Wilcoxon-test). The computer based detection of bronchial breathing can be considered useful as part of a quantitative monitoring of patients at risk to develop pneumonia.     

An x-ray study of the subcutaneous tissue using an artificial method of providing contrast]

The paper is concerned with the main methodological principles and potentialities of a radiocontrast study of subcutaneous fat to detect pathological changes in it. The proposed method consists in slow administration in the middle fat layers of 20-25% solution of verografin from not less than two points, and subsequent roentgenography in a necessary projection. The method was used in 15 patients with various orthopedic diseases for diagnosis of inflammatory, tumorous and degenerative-dystrophic diseases.     

褐菖鲉的听觉阈值研究

利用听觉诱发电位记录技术研究了褐菖鲉(Sebasticus marmoratus)的听觉阈值。通过采用听觉生理系统记录和分析了8尾褐菖鲉对频率范围在100—1000 Hz的7种不同频率的声音刺激的诱发电位反应。结果表明, 褐菖鲉的听觉阈值在整体上随着频率增加而增加, 对100—300 Hz的低频声音信号敏感, 最敏感频率为150 Hz, 对应的听觉阈值为70 dB re 1 μPa。褐菖鲉的听觉敏感区间与其发声频率具有较高的匹配性, 表明其声讯交流的重要性。同时, 人为低频噪声可能对其声讯交流造成影响。     

Early detection of pulmonary congestion and edema in dogs by using lung sounds

Five mongrel dogs (2 interstitial and 3 alveolar edema) were studied. Lung mechanics were measured by recording the flow, volume, and esophageal pressure according to the standard technique. Edema was produced by infusion of Ringer lactate solution. Lung sounds were recorded on tape from the dependent part of the chest wall. Lung sound signals were high-pass filtered at 100 Hz and subjected to fast Fourier transform. Samples of lung sounds were analyzed before (control) and at 5, 10, 20, 30, and 40 min after the infusion. The mean, median, and mode frequencies of sound power spectra at the control time were, respectively, 169.6 +/- 29.19, 129.6 +/- 29.81, and 136.0 +/- 29.87 (SD) Hz. These values increased significantly at 5 min after infusion to 194.0 +/- 26.08 (P less than 0.0037), 150.2 +/- 23.48 (P less than 0.0085), and 164.6 +/- 28.74 Hz (P less than 0.02), respectively. These values stayed significantly elevated at 10, 20, 30, and 40 min. The pulmonary wedge pressure, lung dynamic compliance, and pulmonary resistance were measured also at the same times. The mean, median, and mode frequencies correlated with pulmonary wedge pressure (P less than 0.00001, P less than 0.0001, P less than 0.0001), lung dynamic compliance (P less than 0.001, P less than 0.0001, P less than 0.0001), and pulmonary resistance (P less than 0.00001, P less than 0.00001, P less than 0.0001), respectively. There were no significant adventitious sounds up to 40 and 50 min after infusion. We concluded that pulmonary congestion and early edema alter the frequency characteristics of lung sounds early, before the occurrence of adventitious sounds. These altered lung sounds may be used as an index of pulmonary congestion and impending edema.     

Mobile nocturnal long-term monitoring of wheezing and cough.

Changes in normal lung sounds are an important sign of pathophysiological processes in the bronchial system and lung tissue. For the diagnosis of bronchial asthma, coughing and wheezing are important symptoms that indicate the existence of obstruction. In particular, nocturnal long-term acoustic monitoring and assessment make sense for qualitative and quantitative detection and documentation. Previous methods used for lung function diagnosis require active patient cooperation that is not possible during sleep. We developed a mobile device based on the CORSA standard that allows the recording of respiratory sounds throughout the night. To date, we have recorded 133 patients with different diagnoses (80 male, 53 female), of whom 38 were children. In 68 of the patients we could detect cough events and in 87 we detected wheezing. The recording method was tolerated by all participating adults and children. Our mobile system allows non-invasive and cooperation-independent nocturnal monitoring of acoustic symptoms in the domestic environment, especially at night, when most ailments occur.     

Characterization of pathology and parasite load in outbred and inbred mouse models of chronic Neospora caninum infection

Here, we analyzed histological findings and parasite burden in chronic Neospora caninum infection in BALB/c and ICR mice and studied the correlation between lesion severity and parasite load in brain. To obtain a better understanding of the infection, we examined the influence of various host pathogen factors. Groups of outbred (ICR) and inbred (BALB/c) mice were inoculated using several NC-1 parasite doses (4 x 10(5), 10(6), and 5 x 10(6) tachyzoites), inoculation routes (intraperitoneal and subcutaneous), and 3 immunosuppressive treatments (methylprednisolone, cyclophosphamide, and vinblastine). Lesion severity was analyzed in the liver, lung, heart, and brain tissues, and parasite load was measured by real-time polymerase chain reaction in brain tissue. The results indicated more severe cerebral lesions and higher brain parasite burdens in inbred than in outbred mice. Hepatic tissue was the primary lesion site in immunosuppressed ICR mice. We also observed that increased inoculum size was reflected in greater lesion severity and a higher cerebral parasite load. No difference was observed with respect to inoculation route. The study also showed an association between brain parasite burden and severity of cerebral lesions in BALB/c mice.     

Volume conduction models for surface EMG; confrontation with measurements

Volume conduction models are used to describe and explain recorded motor unit potentials (MUPs). So far it has remained unclear which factors have to be taken into account in a volume conduction model. In the present study, five different models are confronted with measured MUP distributions over the skin surface above the m. biceps brachii generated by MUs at different depths and recorded by small surface electrodes. All model simulations include fibres of finite length. The models differ in the size of the volume conductor (finite/infinite), the number of different layers (1, 2 or 3) and the conductivities of these layers (representing muscle, subcutaneous fat and skin). All measured and simulated MUPs contain a mainly negative propagating wave followed by a positive wave simultaneously present at all electrode positions. The magnitude of the different MUP components relative to each other and as a function of motor unit (MU) and electrode position differ between the models studied and the measurements. All simulated MUPs changed faster with observation distance than the measured MUPs. The three-layer model, in which muscle tissue was surrounded by a subcutaneous fat layer and by a layer of skin resulted in MUPs closest to the measured MUPs.     

Combined bioluminescence and fluorescence imaging visualizing orthotopic lung adenocarcinoma xenograft in vivo

Lung adenocarcinoma is the most common type of lung cancer. A close monitor of in vivo tumor development may help to better understand the pathogenesis and pathological processes of this disease. A bimodal imaging strategy has been developed, which is a very important tool to investigate the growth and metastasis of lung adenocarcinoma. In the present study, we used a combined labeling strategy in p53RE-luc-A549 cells via transfecting the reporter gene EGFP. In order to unambiguously identify the growth and metastasis of transfected A549 tumor cells, we established and observed subcutaneous and orthotopic xenografts in nude mice by in vivo bioluminescence and fluorescence imaging, which was verified by our post-mortem histological analysis. In vivo bioluminescence signal was observed for the progression of both subcutaneous and orthotopic xenografts in EGFP-p53RE-luc-A549 cells; in vivo fluorescence was only observed for the growth of subcutaneous xenograft of EGFP-p53RE-luc-A549 cells. Moreover, EGFP-p53RE-luc-A549 cells allow for the improved identification of implanted cells within host tissue during histological analysis. In conclusion, we presented a combined labeling strategy for bimodal A549 cell imaging which leads to improved detection of cellular grafts.     

Analysis of shear wave propagation in skin; application to an experimental procedure

An analysis of an experimental procedure used to determine age-related changes in the skin was performed. The experiment is based on the propagation of a shear wave through the skin. The analysis of the experiment was used to determine the effects of parameters such as properties of the skin and subcutaneous fat, skin thickness and experimental conditions on the propagation. Computer simulations showed that at lower frequencies (less than 1000 Hz), measured results depended strongly on skin thickness, while at higher frequencies (2000 Hz) the results were relatively insensitive to both skin thickness and the properties of the subcutaneous fat. Results also depended upon the distance between the applied shear disturbance and the measurement point. The analysis suggests that higher frequency (2000 Hz) experimental results are more indicative of mechanical properties of skin than lower frequency (less than 1000 Hz) results.     

Auditory and olfactory abilities of larvae of the Indo-Pacific coral trout Plectropomus leopardus (Lacepède) at settlement

Auditory and olfactory abilities of settlement-stage larvae of the coral trout Plectropomus leopardus (Pisces: Serranidae) were tested electrophysiologically to determine if these senses are sufficiently developed to aid larvae in detection of settlement habitats on coral reefs. Plectropomus leopardus larvae detected sounds from 100 to 2000 Hz with hearing most sensitive at the frequencies of 100, 200 and 600 Hz. The olfactory response of P. leopardus was similar for the two amino acids tested and for the water conditioned by conspecifics. Auditory and olfactory abilities of P. leopardus are well developed at settlement-stage, and apparently sufficient to detect auditory and olfactory cues from reefs.     

Sounds recorded in salt marshes and attributed to the European eel

The sounds were recorded in coastal ponds off the French Atlantic coast. They are characterized by continuous series of regularly spaced sounds, each sound being composed of one to four pulses of 7.8-ms duration. The main frequencies of these sounds are under 350 Hz. Due to the special characteristics of these sounds, their temporal patterning, their coastal pond provenance and their close similarity to sounds made by the American eel (Anguilla rostrata), we attribute them to the European eel (Anguilla anguilla).     

SOUND AND ITS SIGNIFICANCE FOR LABORATORY ANIMALS

1. Several methods of varying accuracy have been used to assess what sounds small laboratory animals such as rodents are capable of hearing. Most rodents can detect sounds from 1000 Hz (the frequency of the Greenwich Time Signal) up to 100000 Hz, depending on the strain, with usually one or more commonly two peaks of sensitivity within this range. Dogs can detect sound most easily from 500 Hz to 55000 Hz, depending on the breed. 2. Rodents also produce sound signals as a behavioural response and for communication in a variety of situations. Ultrasonic calls in the range 22000–70000 Hz are the main communicating pathway during aggressive encounters, mating, and mothering. Similar calls have also been recorded from isolated animals associated with inactivity, rest and possibly even sleep. 3. Very loud sounds cause seizures in rats and mice, or can make them more susceptible to other sounds later in life. This effect is possible even when animals are fully anaesthetized. Sound tends to startle and reduce activity in several species of animal. Even offspring of mice that have been sound-stressed exhibit abnormal behaviour patterns. Sounds also elicit various responses in rats from increasing aggression to making them more tolerant to electric shocks. 4. Levels of sound above 100 dB are teratogenic in several species of animals and several hormonal, haematological and reproductive parameters are disturbed by sounds above 80 dB. When rats are chemically deafened the disturbance to their fertility disappears. Lipid metabolism is disrupted in rats when exposed to over 95 dB of sounds, leading to increases in plasma triglycerides. Atherosclerosis can be produced in rabbits by similar levels of sound. 5. It has also been shown in guinea pigs and cats that hearing damage is governed by the duration as well as the intensity of the sound and is irreversible. Work on chinchillas hs demonstrated that sounds above 95 dB lead to this injury, but that sounds of 80 dB have no permanent effect on hearing sensitivity.     

Auditory sensitivity in settlement-stage larvae of coral reef fishes

The larval phase of most species of coral reef fishes is spent away from the reef in the pelagic environment. At the time of settlement, these larvae need to locate a reef, and recent research indicates that sound emanating from reefs may act as a cue to guide them. Here, the auditory abilities of settlement-stage larvae of four species of coral reef fishes (families Pomacentridae, Lutjanidae and Serranidae) and similar-sized individuals of two pelagic species (Carangidae) were tested using an electrophysiological technique, auditory brainstem response (ABR). Five of the six species heard frequencies in the 100–2,000 Hz range, whilst one carangid species did not detect frequencies higher than 800 Hz. The audiograms of the six species were of similar shape, with best hearing at lower frequencies between 100 and 300 Hz. Strong within-species differences were found in hearing sensitivity both among the coral reef species and among the pelagic species. Larvae of the coral reef species had significantly more sensitive hearing than the larvae of the pelagic species. The results suggest that settlement-stage larval reef fishes may be able to detect reef sounds at distances of a few 100 m. If true hearing thresholds are lower than ABR estimates, as indicated in some comparisons of ABR and behavioural methods, the detection distances would be much larger.     

Orthogonal factor coefficient development of subcutaneous adipose tissue topography (SAT-Top) in girls and boys

The new optical device Lipometer allows noninvasive, quick, and safe determination of the thickness of subcutaneous adipose tissue (SAT) layers (in mm) at any site of the human body. The specification of 15 evenly distributed body sites enables the precise measurement of subcutaneous body fat distribution, so-called subcutaneous adipose tissue topography (SAT-Top). SAT-Top was measured in 980 children aged 7-19 years. In this paper we describe the degree to which SAT-Top body sites are intercorrelated. We consider whether a meaningful reduction of data is possible using factor analysis, which factors can be extracted, and how SAT-Top data of children can be added to a factor value plot, depicting the essential results of age-dependent subcutaneous fat development. SAT layers situated on the same body area provide correlation coefficients up to +r = 0.91. Two factors are extracted: factor 1, containing all upper body sites (from neck to hip); and factor 2, consisting of all leg body sites. When all 980 children are divided into three age groups in a factor value plot, the first age group (7-11 years) shows almost equal SAT-Top development in boys and girls. Afterwards, for the consecutive age groups 2 (11-15 years) and 3 (15-19 years), the age-dependent subcutaneous fat development of boys and girls progresses into nearly orthogonal directions.     

Mild obesity does not limit change in end-expiratory lung volume during cycling in young women.

To investigate the effects of obesity on the regulation of end-expiratory lung volume (EELV) during exercise we studied nine obese (41 +/- 6% body fat and 35 +/- 7 yr, mean +/- SD) and eight lean (18 +/- 3% body fat and 34 +/- 4 yr) women. We hypothesized that the simple mass loading of obesity would constrain the decrease in EELV in the supine position and during exercise. All subjects underwent respiratory mechanics measurements in the supine and seated positions, and during graded cycle ergometry to exhaustion. Data were analyzed between groups by independent t-test in the supine and seated postures, and during exercise at ventilatory threshold and peak. Total lung capacity (TLC) was reduced in the obese women (P < 0.05). EELV was significantly lower in the obese subjects in the supine (37 +/- 6 vs. 45 +/- 5% TLC) and seated (45 +/- 6 vs. 53 +/- 5% TLC) positions and at ventilatory threshold (41 +/- 4 vs. 49 +/- 5% TLC) (P < 0.01). In conclusion, despite reduced resting lung volumes and alterations in respiratory mechanics during exercise, mild obesity in women does not appear to constrain EELV during cycling nor does it limit exercise capacity. Also, these data suggest that other nonmechanical factors also regulate the level of EELV during exercise.     

Hearing in honeybees: operant conditioning and spontaneous reactions to airborne sound

Summary Airborne sound signals emitted by dancing bees (Apis mellifera) play an essential role in the bees' dance communication. It has been shown earlier that bees can learn to respond to airborne sounds in an aversive conditioning paradigm. Here we present a new training paradigm. A Y-choice situation was used to determine the frequency range and amplitude thresholds of hearing in bees. In addition, spontaneous reactions of bees to airborne sound were observed and used to determine thresholds of hearing. Both methods revealed that bees are able to detect sound frequencies up to about 500 Hz. The hearing threshold is 100–300 mm/s peak-to-peak velocity and is roughly constant over the range of detectable frequencies. The amplitude of the signals emitted in the dance language is 5 to 10 times higher, so we can conclude that bees can easily detect the dance sounds.     

Parametric representation of normal breath sounds.

The spectral content of normal tracheal and chest wall breath sounds has been calculated using the fast Fourier transform (FFT) (J. Appl. Physiol. 50: 307-314, 1981). Parameter estimation methods, in particular autoregressive (AR) modeling, are alternative techniques for measuring lung sounds. The outcome of AR modeling of 38 complete breaths picked up simultaneously over the chest walls and tracheae of five normal males was evaluated. The sounds were treated as noise, bounded by a quasi-periodic envelope generated by the cyclic action of breathing, thus causing the sounds to become inherently nonstationary. Normalization of the sounds to their corresponding variance envelopes eliminated the nonstationarity, an important requirement for most signal-processing methods. Subsequently, the AR model order was sought using formal criteria. Orders 6-8 were found to be suitable for normal chest wall sounds, whereas tracheal sounds required at least orders 12-16. Using orders 6 and 12, we compared the prominent spectral features of chest wall and tracheal sounds calculated by AR with those found in the spectra calculated by FFT. The polar representation of the AR roots, calculated from the AR coefficients, showed that normal lung sounds from a group of individuals are characterized by a low variability, suggesting that this method may provide an alternative representation of the sounds. The data presented here show that normal lung sounds, when measured in the frequency domain by either FFT or AR modeling, have a characteristic pattern that is independent of the analysis method.     

PPARγ与c/EBPα基因在苏太猪不同组织中的表达水平探究

为探究PPARγ与c/EBPα基因在苏太猪不同组织中的表达与脂肪沉积的关系,本实验以10月龄苏太猪为研究对象,运用实时荧光定量PCR (q RT-PCR)技术检测PPARγ与c/EBPα基因mRNA在苏太猪心、肝、脾、肺、肾、胃、背最长肌和皮下脂肪8个组织中的表达水平。结果表明,PPARγ与c/EBPα基因在苏太猪的8个组织中均有不同程度的表达,其中,PPARγ基因在苏太猪脾脏组织中的表达量最高,皮下脂肪中的表达水平仅次于脾;以背最长肌中PPARγ基因的相对表达量作对比,背最长肌与脾、肺和皮下脂肪的相对表达差异极显著(p<0.01),其余为差异不显著(p>0.05),表达量高低顺序为脾>皮下脂肪>肺>心>胃>肾>肝>背最长肌;c/EBPα基因在苏太猪的皮下脂肪的表达量最高,以背最长肌中c/EBPα基因的相对表达量作对比,在肝、脾、皮下脂肪组织中表达差异极显著(p<0.01),肺的相对表达差异显著(p<0.05),其余组织中差异不显著(p>0.05),表达量的高低顺序为皮下脂肪>肝>脾>肺>肾>心>胃>背最长肌。两基因在各组织中表达趋势趋于一致。试验结果表明PPARγ和c/EBPα基因可能对猪脂肪沉积有重要影响。     

Sound production, hearing and possible interception under ambient noise conditions in the topmouth minnow Pseudorasbora parva

Sounds were produced by the topmouth minnow Pseudorasbora parva , a common Eurasian cyprinid, during feeding but not during intraspecific interactions. Feeding sounds were short broadband pulses with main energies between 100 and 800 Hz. They varied in their characteristics (number of single sounds per feeding sequence, sound duration and period, and sound pressure level) depending on the food type (chironomid larvae, Tubifex worms and flake food). The loudest sounds were emitted when food was taken up at the water surface, most probably reflecting 'suctorial' feeding. Auditory sensitivities were determined between 100 and 4000 Hz utilizing the auditory evoked potentials recording technique. Under laboratory conditions and in the presence of natural ambient noise recorded in Lake Neusiedl in eastern Austria, best hearing sensitivities were between 300 and 800 Hz (57 dB re 1 μPa v . 72 dB in the presence of ambient noise). Threshold-to-noise ratios were positively correlated to the sound frequency. The correlation between sound spectra and auditory thresholds revealed that P. parva can detect conspecific sounds up to 40 cm distance under ambient noise conditions. Thus, feeding sounds could serve as an auditory cue for the presence of food during foraging.