Prediction of quantitative intrathoracic fluid volume to diagnose pulmonary oedema using LabVIEW

Pulmonary oedema is a life-threatening disease that requires special attention in the area of research and clinical diagnosis. Computer-based techniques are rarely used to quantify the intrathoracic fluid volume (IFV) for diagnostic purposes. This paper discusses a software program developed to detect and diagnose pulmonary oedema using LabVIEW. The software runs on anthropometric dimensions and physiological parameters, mainly transthoracic electrical impedance (TEI). This technique is accurate and faster than existing manual techniques. The LabVIEW software was used to compute the parameters required to quantify IFV. An equation relating per cent control and IFV was obtained. The results of predicted TEI and measured TEI were compared with previously reported data to validate the developed program. It was found that the predicted values of TEI obtained from the computer-based technique were much closer to the measured values of TEI. Six new subjects were enrolled to measure and predict transthoracic impedance and hence to quantify IFV. A similar difference was also observed in the measured and predicted values of TEI for the new subjects.     

Prediction of trabecular bone principal structural orientation using quantitative ultrasound scanning

Bone has the ability to adapt its structure in response to the mechanical environment as defined as Wolff's Law. The alignment of trabecular structure is intended to adapt to the particular mechanical milieu applied to it. Due to the absence of normal mechanical loading, it will be extremely important to assess the anisotropic deterioration of bone during the extreme conditions, i.e., long term space mission and disease orientated disuse, to predict risk of fractures. The propagation of ultrasound wave in trabecular bone is substantially influenced by the anisotropy of the trabecular structure. Previous studies have shown that both ultrasound velocity and amplitude is dependent on the incident angle of the ultrasound signal into the bone sample. In this work, seven bovine trabecular bone balls were used for rotational ultrasound measurement around three anatomical axes to elucidate the ability of ultrasound to identify trabecular orientation. Both ultrasound attenuation (ATT) and fast wave velocity (UV) were used to calculate the principal orientation of the trabecular bone. By comparing to the mean intercept length (MIL) tensor obtained from μCT, the angle difference of the prediction by UV was 4.45°, while it resulted in 11.67° angle difference between direction predicted by μCT and the prediction by ATT. This result demonstrates the ability of ultrasound as a non-invasive measurement tool for the principal structural orientation of the trabecular bone.     

Effect of antihistamines on anaphylactoid oedema in rats using a modified plethysmometer for measuring foot volume.

This study reports the quantitative effect of the H1--and H2--receptor antagonists on dextran-induced anaphylactoid oedema in rats. The findings indicate that mepyramine, promethazine and chlorpromazine which are H1--receptor antagonists significantly inhibited this anaphylactoid oedema. While on the other hand burimamide an H2--receptor antagonist at doses below 500 micrograms/kg inhibit dextran-induced oedema but at higher doses enhances oedema formation in the test rats. E.D50 values obtained for mepyramine, chlorpromazine and promethazine are 5.01 mg/kg, 0.36 mg/kg, 1.78 mg/kg respectively. The dual effects of burimamide on dextran-induced oedema merits further investigation and confirmation with the aid of other H1--and/or H2--receptor systems. A modification of the plethysmometric method of Buttle et. al. (1957) is also described.     

On volume regulation leading to epithelial fluid transport

Walker, V. E., J. W. Stelling, H. E. Miley, and T. J. C. Jacob. Effect ofcoupling on volume-regulatory response of ciliary epithelial cells suggestsmechanism for secretion. Am. J. Physiol. 276 (Cell Physiol. 45):C1432-C1438, 1999.The ciliary epithelium of the eye secretes theaqueous humor. It is a double epithelium arranged so that the apical surfacesof the nonpigmented ciliary epithelial (NPCE) and pigmented ciliary epithelial(PCE) cells face each other and the basolateral membranes face the inside ofthe eye and the blood, respectively. We have investigated the volumeresponses of both single cells and coupled pairs from this tissue to osmoticchallenge. Both NPCE and PCE cells undergo regulatory volume increase(RVI) and decrease (RVD) when exposed to hyper- and hyposmoticsolution, respectively. In hyposmotic solution single cells swell and return totheir original volumes within ~3 min. In nonpigmented cells RVD could beinhibited by blockers of volume-activated Cl channels [tamoxifen(100%) > quinidine (87%) > DIDS(84%) > 5-nitro-2-(3-phenylpropylamino)benzoic acid (80%) > SITS(58%)] and K+ channels [Ba2+ (31%)]. However, in PCE cells theseinhibitors and additionally tetraethylammonium and Gd3+ were without effect.Only bumetanide, an inhibitor of Na+-K+-2Cl cotransport, was found tohave any effect on RVD in PCE cells. NPCE-PCE cell coupled pairs alsounderwent RVD, but with altered kinetics. The onset of RVD of the PCEcell in a pair occurred 80 s before that of the NPCE cell, and the peakswell was reduced. This is consistent with fluid movement from the PCE tothe NPCE cell. The effect of the volume-activated Cl channel inhibitortamoxifen was to eliminate this difference in the times of onset of RVD incoupled cell pairs and to inhibit RVD in both the NPCE and PCE cellspartially. On the basis of these observations we suggest that fluid istransferred from the PCE to the NPCE cell in coupled pairs during cellswelling and the subsequent RVD. Furthermore, we speculate that reciprocalRVI-RVD could underlie aqueous humor secretion.

     

Treatment of canine aspiration pneumonitis: fluid volume reduction vs. fluid volume expansion

The aspiration of gastric acid causes pulmonary edema and hypoxemia. One approach to the management of this syndrome is to raise cardiac output (Qt) and O2 delivery (QO2) to ensure tissue oxygenation (VO2) at the risk of increasing the edema. Another approach reduces the edema by reducing pulmonary microvascular pressure (Pmv) at the risk of reducing QO2 and VO2. We compared these approaches in 24 anesthetized, ventilated dogs with pulmonary wedge pressure (Ppw), a clinical approximation of Pmv, of 12.5 mmHg. Before and again 1 h after endobronchial instillation of 0.1 N HCl, we measured Qt, QO2, VO2, venous admixture, and in vivo extravascular lung liquid. The dogs were then randomly divided into four equal groups: 1) 12.5 mmHg Ppw, high Qt; 2) 7.5 mmHg Ppw, intermediate Qt; 3) 4.5 mmHg Ppw, low Qt; and 4) 4.5 mmHg Ppw plus dopamine, intermediate Qt. Measured values were followed for 4 more h, after which the lungs were excised to compare wet weight-to-body weight ratios (W/B). When plasmapheresis reduced Ppw at 1 h, edema did not increase further and W/B of groups 2 (21 +/- 3), 3 (18 +/- 3), and 4 (22 +/- 3) were significantly less than in group 1 (27 +/- 3) (P less than 0.001). Although Qt decreased with Ppw, increased hematocrit and reduced venous admixture maintained QO2 in group 2 but not in group 3. In group 4 an intermediate Qt maintained QO2 even at 4.5 mmHg Ppw but edema increased to the group 2 level presumably because Pmv rose with Qt on dopamine. VO2 remained constant over time in each group. These data demonstrate that canine HCl-induced pulmonary edema, measured in vivo or gravimetrically, is very sensitive to reductions in Pmv. Moreover, the lowest Pmv (and QO2) was well tolerated because an O2 supply dependency of VO2 was not observed.     

Study of cough in anaesthetized cats with experimental pulmonary oedema

The authors studied parameters of laryngopharyngeal (LPh) and tracheobronchial (TB) cough (the number of efforts--NE, the number of efforts per minute--NE.min-1, the intensity of the maximum effort--IME and the intensity of the attack--IA), respiratory parameters (VT, f, Cdyn), blood gas values (PaO2, PaCO2) and the pH in the arterial blood of anaesthetized cats (Pentobarbital Spofa, 35 mg x kg-1 i.p. with experimental pulmonary oedema. Oedema was induced by the i.v. administration of a fatty acid mixture (capric acid 3.8 g, caprylic acid 3.1 g and olive oil 3.0 g)--in a dose of 0.05 ml x kg-1 in group 1 and of 0.01 ml x kg-1 in group 2. Cough was elicited by stimulating the laryngopharyngeal and tracheobronchial mucosa with a silon fibre. Pulmonary oedema was determined from a macroscopic and microscopic examination of the lungs, from the ratio of lung weight to body weight and from the percentual dry weight of the right lungs. The authors found that the intensity of cough was depressed during pulmonary oedema, particularly in the case of TB cough. VT and Cdyn fell, f rose and the PaO2 and pH values steadily decreased.     

Feasibility of using cryopreserved lymphoblastoid cells to diagnose some lysosomal storage diseases

Objectives: The Epstein–Barr virus (EBV) is utilized as a tool in the study of cellular biology because of its capacity to transform B‐lymphocytes. For this reason, EBV is used in conservation of human B‐lymphocytes for long periods for subsequent evaluation of lysosomal hydrolase activity. Lymphoblastoid cell lines have several advantages for use over other cell types, such as prompt availability and possibility to develop, characterize and standardize cell banks, to test effects of promising pharmaceutical reagents. The study below presents biochemical data that demonstrate validity of lymphoblastoid cell lines for diagnosis of GM1‐gangliosidosis, Gaucher, Fabry and Pompe diseases and mucopolysaccharidosis type I. Materials and methods: Cultures were prepared from peripheral blood, collected from 25 normal subjects and 13 affected individuals. Enzyme activities and immunohistochemistry (IHC) were measured. Activities of enzymes β‐galactosidase, β‐glucosidase, α‐iduronidase, α‐galactosidase and α‐glucosidase were measured before and after cryopreservation for 180 days. Enzymatic activity was measured when transformation was confirmed by IHC. Results: We observed some significant alterations in enzymatic activity of non‐cultured cells when compared to others that had been cultured for 12 days and kept frozen for 180 days. Conclusions: However, these alterations did not invalidate use of the technology of transformation of lymphoblastoid cell lines with EBV, to diagnose the diseases mentioned above, in view of the fact that the cultured cells, before and after freezing, demonstrated similar enzymatic activities.     

Nanocarriers as pulmonary drug delivery systems to treat and to diagnose respiratory and non respiratory diseases

The purpose of this review is to discuss the impact of nanocarriers administered by pulmonary route to treat and to diagnose respiratory and non respiratory diseases. Indeed, during the past 10 years, the removal of chlorofluorocarbon propellants from industrial and household products intended for the pulmonary route has lead to the developments of new alternative products. Amongst these ones, on one hand, a lot of attention has been focused to improve the bioavailability of marketed drugs intended for respiratory diseases and to develop new concepts for pulmonary administration of drugs and, on the other hand, to use the pulmonary route to administer drugs for systemic diseases. This has led to some marketed products through the last decade. Although the introduction of nanotechnology permitted to step over numerous problems and to improve the bioavailability of drugs, there are, however, unresolved delivery problems to be still addressed. These scientific and industrial innovations and challenges are discussed along this review together with an analysis of the current situation concerning the industrial developments.     

Cerebral blood flow velocity responses to hypoxia in subjects who are susceptible to high-altitude pulmonary oedema

Cerebral blood flow increases on exposure to high altitude, and perhaps more so in subjects who develop acute mountain sickness. We determined cerebral blood flow by transcranial Doppler ultrasound of the middle cerebral artery at sea level, in normoxia (fraction of inspired O2, F(I)O2 0.21), and during 15-min periods of either hypoxic (F(I)O2 0.125) or hyperoxic (F(I)O2 1.0) breathing, in 7 subjects with previous high-altitude pulmonary oedema, 6 climbers who had previously tolerated altitudes between 6000 m and 8150 m, and in 20 unselected controls. Hypoxia increased mean middle cerebral artery flow velocity from 69 (3) to 83 (4) cm x s(-1) (P<0.001) in the controls, from 63 (3) to 75 (3) cm x s(-1) (P<0.001) in the high-altitude pulmonary-oedema-susceptible subjects, and from 58 (4) to 70 (4) cm x s(-1) (P<0.001) in the successful high-altitude climbers. Hyperoxia decreased mean middle cerebral flow velocity to 60 (3) cm x s(-1) (P<0.001), 53 (3) cm x s(-1) (P<0.01), and 49 (3) cm x s(-1) (P<0.01) in the controls, high-altitude pulmonary-oedema-susceptible, and high-altitude climbers, respectively. We conclude that a transcranial Doppler-based estimate of cerebral blood flow is affected by hypoxic and hyperoxic breathing, and that it is not predictive of tolerance to high altitude.     

Prediction of flowering time in Brassica oleracea using a quantitative trait loci-based phenology model

Uniformly developing plants with a predictable time to harvest or flowering under unfavourable climate conditions are a major breeding goal in crop species. The main flowering regulators and their response to environmental signals have been identified in Arabidopsis thaliana and homologues of flowering genes have been mapped in many crop species. However, it remains unclear which genes determine within and across genotype flowering time variability in Brassica oleracea and how genetic flowering time regulation is influenced by environmental factors. The goal of this study is model-based prediction of flowering time in a B. oleracea DH-line population using genotype-specific and quantitative trait loci (QTL) model input parameters. A QTL-based phenology model accounting for genotypic differences in temperature responses during vernalisation and non-temperature-sensitive durations from floral transition to flowering was evaluated in two field trials. The model was parameterised using original genotype-specific model input parameters and QTL effects. The genotype-specific model parameterisation showed accurate predictability of flowering time if floral induction was promoted by low temperature (R(2) = 0.81); unfavourably high temperatures reduced predictability (R(2) = 0.65). Replacing original model input parameters by QTL effects reduced the capability of the model to describe across-genotype variability (R(2) = 0.59 and 0.50). Flowering time was highly correlated with a model parameter accounting for vernalisation effects. Within-genotype variability was significantly correlated with the same parameter if temperature during the inductive phase was high. We conclude that flowering time variability across genotypes was largely due to differences in vernalisation response, although it has been shown elsewhere that the candidate FLOWERING LOCUS C (FLC) did not co-segregate with flowering time in the same population. FLC independent vernalisation pathways have been described for several species, but not yet for B. oleracea.     

每搏量变异度在围手术期容量治疗监测中的应用

每搏量变异度是动态的容量监测指标.机械通气患者心肺的相互作用是每搏量变异度的产生基础,通过动脉压力波形分析技术可以进行连续监测.每搏量变异度能够准确预测容量治疗反应,与静态的血流动力学参数相比,对于优化心输出量和组织氧供更有优势,但也存在一定的局限性.每搏量变异度受多种因素影响且不能用于自主呼吸和心律失常的患者.临床应用时应该综合考虑其影响因素,结合其他的指标和方法指导容量治疗.     

Treatment of myocardial dysfunction and pulmonary oedema in an infant chimpanzee

Abstract: The care of any critically ill infant requires special technical equipment for monitoring of cardiac and pulmonary functions including mechanical ventilators and blood gas analysers. The present paper describes the treatment of myocardial dysfunction and pulmonary distress, complicated by severe brain oedema in an infant chimpanzee admitted to an intensive care unit in the Department of Neonatology of the Children's Hospital of the University of Leipzig. The condition of the chimpanzee was diagnosed and monitored by standard clinical tooös including radiography, echocardiography, cerebral Doppler sonography and laboratory parameters. The chimpanzee was treated in close cooperation between veterinarians and paediatricians.