Affective response to whole-body cryotherapy: Influence of sex, body mass index, age, time of day, and past experience.

OBJECTIVE: Whole-Body Cryotherapy (WBC) has seen a recent surge in popularity with patients with inflammatory conditions, athletes, and even people seeking to improve general health and quality of life. WBC treatment usually requires participation in a dozen of 3-min long sessions. But compliance is considered difficult due to possible cold-induced unpleasant sensations. Based on hedonic psychology assumptions, ratings of pleasure-displeasure experienced during a taks or activity may be important to understand individual differences in attendance. METHODS: Two hundred fifty nine customers from two French cryocenters took the Feeling Scale immediately after their first WBC session. RESULTS: End affect appeared to be negatively valenced (M = -1.85, SD = 1.38, 95 % confidence interval: -2.02 to -1.68). Additional statistical analyses revealed a moderating influence of past experience, in women only. Similarly, BMI was found to be negatively associated with displeasure in women, but not in men. CONCLUSION: These findings are discussed and further research directions are suggested.

Preliminary study on the effect of sex on skin cooling response during whole body cryostimulation (-110 °C): Modeling and prediction of exposure durations.

In order to determine the required duration of whole-body exposure to extreme cold (-110 °C) in males and females for achieving the same cold-induced response, a mathematical model of skin cooling kinetics was developed. This modeling is derived from the implementation of a new experimental cryotherapy protocol to obtain continuous skin temperature maps over time. Each 3-min whole-body cryostimulation session was divided into six incremental sessions of 30 s carried out over six consecutive days. Seventeen young, healthy subjects (8 males aged 22.6 ±3.0 years and 9 females aged 23.7 ±4.7 years) agreed to participate in this study. The smallest sex-related difference in temperature was found in the trunk area (2.93 °C after 3 min) while the greatest temperature drop was found in the lower limbs (5.92 °C after 3 min). The largest temperature variation was observed between the trunk and the lower limbs, and peaked at 2.67 °C in males and 6.99 °C in females. For both sexes, skin cooling kinetics showed a strong transient exponential type decrease followed by linear regression behavior. It appeared that for achieving the same cold-induced response, the required duration of cryostimulation is longer for males. For example, a trunk skin cooling of -12 °C could be achieved in 125s for females vs 170s for males (+36% longer); for the lower limbs, the same skin cooling magnitude could be reached after 87s for females vs 140s for males (+62% longer).

Aerodynamic investigation of the thermo-dependent flow structure in the wake of a cyclist.

The main purpose of this study was to assess the influence of the environmental temperature on both the aerodynamic flow evolving around the bicycle and cycling power output. The CFD method was used to investigate the detailed flow field around the cyclist/bicycle system for a constant speed of 11.1 m/s (40 km/h) without wind. In complement, a mathematical model was used to determine the temperature-dependent power output in the range [-10; 40 °C]. The numerical investigation gives valuable information about the turbulent flow field in the cyclist's wake which evolves accordingly the surrounding temperature. A major result of this study is that the areas of overpressure upstream of the cyclist and of underpressure downstream of him are less extensive for a temperature of 40 °C compared to -10 °C. The results suggest that the aerodynamic braking effect of the bicycle is minimized when the air temperature is high, as a lower air density results in a reduction in drag on the cyclist. This study showed that the power required to maintain a constant speed is reduced when the temperature is high, the reason being a lower aerodynamic resistance.

Aerodynamic study of time-trial helmets in cycling racing using CFD analysis.

The aerodynamic drag of three different time-trial cycling helmets was analyzed numerically for two different cyclist head positions. Computational Fluid Dynamics (CFD) methods were used to investigate the detailed airflow patterns around the cyclist for a constant velocity of 15 m/s without wind. The CFD simulations have focused on the aerodynamic drag effects in terms of wall shear stress maps and pressure coefficient distributions on the cyclist/helmet system. For a given head position, the helmet shape, by itself, obtained a weak effect on a cyclist's aerodynamic performance (<1.5%). However, by varying head position, a cyclist significantly influences aerodynamic performance; the maximum difference between both positions being about 6.4%. CFD results have also shown that both helmet shape and head position significantly influence drag forces, pressure and wall shear stress distributions on the whole cyclist's body due to the change in the near-wake behavior and in location of corresponding separation and attachment areas around the cyclist.

Numerical investigation of the early flight phase in ski-jumping.

The purpose of this study is to develop a numerical methodology based on real data from wind tunnel experiments to investigate the effect of the ski jumper's posture and speed on aerodynamic forces in a wide range of angles of attack. To improve our knowledge of the aerodynamic behavior of the ski jumper and his equipment during the early flight phase of the ski jump, we applied CFD methodology to evaluate the influence of angle of attack (α=14°, 21.5°, 29°, 36.5° and 44°) and speed (u=23, 26 and 29m/s) on aerodynamic forces in the situation of stable attitude of the ski jumper's body and skis. The standard k-ω turbulence model was used to investigate both the influence of the ski jumper's posture and speed on aerodynamic performance during the early flight phase. Numerical results show that the ski jumper's speed has very little impact on the lift and drag coefficients. Conversely, the lift and drag forces acting on the ski jumper's body during the early flight phase of the jump are strongly influenced by the variations of the angle of attack. The present results suggest that the greater the ski jumper's angle of inclination, with respect to the relative flow, the greater the pressure difference between the lower and upper parts of the skier. Further studies will focus on the dependency of the parameters with both the angle of attack α and the body-ski angle ß as control variables. It will be possible to test and optimize different ski jumping styles in different ski jumping hills and investigate different environmental conditions such as temperature, altitude or crosswinds.

Legionella pneumophila DNA in serum samples during Legionnaires' disease in relation to C-reactive protein levels.

Legionella pneumophila DNA can be detected in serum from patients with Legionnaires' disease (LD). We explored this observation studying the kinetics of L. pneumophila DNA in serum samples in relation to C-reactive protein (CRP). Eleven hospitalized patients with LD were studied. Diagnosis was made by Legionella urinary antigen test in 8 patients and seroconversion in 3 patients. A macrophage infectivity potentiator (MIP) real-time PCR was performed on 31 serum samples, including 20 follow-up serum samples. Serum samples obtained on the day of admission were MIP PCR-positive in 7 (64%) and MIP PCR-negative in 4 (36%) patients. Three (75%) of the 4 patients with a MIP PCR-negative serum sample on the day of admission became positive during follow-up. Overall, L. pneumophila DNA was detected in serum samples from 10 of the 11 patients (91%). CRP levels in the 7 patients with a positive MIP PCR serum sample on day of admission (499 +/- 144 mg/l; median +/- SD) were significantly higher than those in the 4 patients with a negative MIP PCR serum sample on the day of admission (244 +/- 97 mg/l). No difference in the severity of the disease on the day of admission was found between these patients. The presence of L. pneumophila DNA in serum is a common phenomenon in hospitalized patients with LD, although in some cases it is not yet present on the day of admission. L. pneumophila DNA in serum on the day of admission correlates with high CRP levels, but not with the severity of the disease.

Oxidative stress in arterial hypertension: role of NAD(P)H oxidase.

Increased vascular reactive oxygen species production, especially superoxide anion, contributes significantly in the functional and structural alterations present in hypertension. An enhanced superoxide production causes a diminished NO bioavailability by an oxidative reaction that inactivates NO. Exaggerated superoxide levels and a low NO bioavailability lead to endothelial dysfunction and hypertrophy of vascular cells. It has been shown that the enzyme NAD(P)H oxidase plays a major role as the most important source of superoxide anion in vascular cells. Several experimental observations have shown an enhanced superoxide generation as a result of the activation of vascular NAD(P)H oxidase in hypertension. Although this enzyme responds to stimuli such as vasoactive factors, growth factors, and cytokines, some recent data suggest the existence of a genetic background modulating the expression of its different components. New polymorphisms have been identified in the promoter of the p22(phox) gene, an essential subunit of NAD(P)H oxidase, influencing the activity of this enzyme. Genetic investigations of these polymorphisms will provide novel markers for determination of genetic susceptibility to oxidative stress in hypertension.

[Persistent infiltrative pulmonary disease]. / Persisterende infiltratieve longafwijkingen.

Two patients, a woman aged 63 and a man aged 64 years, were admitted with pulmonary complaints and persistent infiltrative lung abnormalities as revealed in chest X-rays. Routine diagnostic analysis did not lead to a diagnosis. However, a pathological examination of biopsies acquired by means of video-assisted thoracoscopic surgery (VATS), revealed bronchiolitis obliterans organising pneumonia (BOOP). In the first patient the BOOP manifested itself as a rapidly progressive disease with fever, pulmonary complaints and X-ray abnormalities. There was no response to standard antibiotic treatment. The other patient had suffered from rheumatoid arthritis for a considerable time and gradually developed BOOP. Both patients recovered following adequate therapy with high doses of oral corticosteroids. BOOP is a pathological-anatomical entity. It is a nonspecific excessive repair response to a variety of stimuli, such as infection, drugs, collagen vascular diseases, inflammatory disorders, transplantation, intoxication and irradiation. BOOP can also occur idiopathically. A high-resolution CT-scan is useful in distinguishing BOOP from interstitial pulmonary fibrosis and other interstitial lung diseases. An open lung biopsy is necessary for the diagnosis BOOP and is best performed by means of VATS. The treatment of BOOP consists of administering high doses of corticosteroids (prednisone 1 mg/kg/day) and if treated adequately, the prognosis is fairly good. Due to the extensive variety in aetiology, the specific diagnostic procedures and the good response to necessary treatment, BOOP should be considered in the differential diagnosis of patients with persistent infiltrative lung disease.

Is the balance between nitric oxide and superoxide altered in spontaneously hypertensive rats with endothelial dysfunction?

BACKGROUND: Increases in oxidant stress, i.e. excessive production of superoxide anion (O2(.-)), have been reported in different models of hypertension. This study was designed to test the hypothesis that increased O2(.-) production, more than diminished nitric oxide (NO) generation, plays a critical role in endothelial dysfunction present in spontaneously hypertensive rats (SHR). METHODS: The study was performed in 30-week-old normotensive Wistar-Kyoto rats (WKY) and SHR. In addition, 16-week-old SHR were treated with oral irbesartan (average dose 20 mg/kg per day) for 14 weeks (SHR-I). Aortic nicotinamide adenine dinucleotide/nicotinamide adenine dinucleotide phosphate (NADH/NADPH) oxidase activity was determined by use of chemiluminescence with lucigenin. Aortic constitutive nitric oxide synthase (cNOS) activity was determined by measuring the conversion of L-arginine to L-citrulline. Vascular responses to acetylcholine were determined by isometric tension studies. RESULTS: Whereas systolic blood pressure (SBP) was significantly increased in SHR compared with WKY, no differences were observed in SBP between SHR-I and WKY. In SHR compared with WKY, we found significantly greater NADH/NADPH-driven O2(.-) production, similar cNOS-mediated NO production and an impaired vasodilation in response to acetylcholine. Treated SHR had similar NADH/NADPH oxidase activity and significantly lower cNOS activity than the WKY group. Vasodilation in response to acetylcholine was improved in SHR-I. CONCLUSIONS: These findings suggest that a diminished availability of NO secondary to an enhanced NADH/NADPH oxidase-dependent O2(.-) production may play a critical role in endothelial dysfunction of adult SHR.

Polymorphisms and promoter overactivity of the p22(phox) gene in vascular smooth muscle cells from spontaneously hypertensive rats.

In a previous study, we found that the p22(phox) subunit of the NADH/NADPH oxidase is overexpressed in vascular smooth muscle cells (VSMCs) from spontaneously hypertensive rats (SHRs) with enhanced vascular production of superoxide anion ((.)O(2)(-)). Thus, we have investigated whether changes in the sequence or activity of the promoter region of p22(phox) gene are present in SHRs. To carry out this analysis, first of all, we characterized the rat gene structure and promoter region for the p22(phox) subunit. The p22(phox) gene spans approximately 10 kb and contains 6 exons and 5 introns. Primer extension analysis indicated the transcriptional start site 100 bp upstream from the translational start site. The immediate promoter region of the p22(phox) gene does not contain a TATA box, but there are a CCAC box and putative recognition sites for nuclear factors, such as SP1, gamma-interferon, and nuclear factor-kappaB. Using reporter-gene transfection analysis, we found that this promoter was functional in VSMCs. Furthermore, we observed that p22(phox) promoter activity was significantly higher in VSMCs from SHRs than from normotensive Wistar-Kyoto rats. In addition, we found that there were 5 polymorphisms in the sequence of p22(phox) promoter between Wistar-Kyoto rats and SHRs and that they were functional. The results obtained in this study provide a tool to explore the mechanisms that regulate the expression of p22(phox) gene in rat VSMCs. Furthermore, our findings show that changes in the sequence of p22(phox) gene promoter and in the degree of activation of VSMCs are responsible for upregulated expression of p22(phox) in SHRs.

Vascular NADH/NADPH oxidase is involved in enhanced superoxide production in spontaneously hypertensive rats.

This study was designed to test the hypothesis that stimulation of nicotinamide adenine dinucleotide/nicotinamide adenine dinucleotide phosphate (NADH/NADPH) oxidase is involved in increased vascular superoxide anion (*O(2)(-)) production in spontaneously hypertensive rats (SHR). The study was performed in 16-week-old and 30-week-old normotensive Wistar-Kyoto rats (WKY(16) and WKY(30), respectively) and in 16-week-old and 30-week-old SHR (SHR(16) and SHR(30), respectively). In addition, 16-week-old SHR were treated with oral irbesartan (average dose 20 mg/kg per day) for 14 weeks (SHR(30)-I). Aortic NADH/NADPH oxidase activity was determined by use of chemiluminescence with lucigenin. The expression of p22phox messenger RNA was assessed by competitive reverse transcription-polymerase chain reaction. Vascular responses to acetylcholine were determined by isometric tension studies. Aortic wall structure was studied, determining the media thickness and the cross-sectional area by morphometric analysis. Whereas systolic blood pressure was significantly increased in the 2 groups of hypertensive animals compared with their normotensive controls, no differences were observed in systolic blood pressure between SHR(30) and SHR(16). No other differences in the parameters measured were found between WKY(16) and SHR(16). In SHR(30) compared with WKY(30), we found significantly greater p22phox mRNA level, NADH/NADPH-driven *O(2)(-) production, media thickness, and cross-sectional area and an impaired vasodilation in response to acetylcholine. Treated SHR had similar NADH/NADPH oxidase activity and p22phox expression as the WKY(30) group. The vascular functional and morphological parameters were improved in SHR(30)-I. These findings suggest that an association exists between p22phox gene overexpression and NADH/NADPH overactivity in the aortas of adult SHR. Enhanced NADH/NADPH oxidase-dependent *O(2)(-) production may contribute to endothelial dysfunction and vascular hypertrophy in this genetic model of hypertension.

p53-mediated upregulation of BAX gene transcription is not involved in Bax-alpha protein overexpression in the left ventricle of spontaneously hypertensive rats.

An association of increased apoptosis with overexpression of the proapoptotic protein Bax-alpha has been reported in the left ventricle of adult spontaneously hypertensive rats (SHR). Both alterations were corrected in SHR that received long-term treatment with the AT1 antagonist losartan. To gain insight into the regulation of cardiac Bax-alpha protein in genetic hypertension, we investigated the expression of the protein p53 (a BAX gene transcription factor) and BAX mRNA in the left ventricle of 30-week-old Wistar-Kyoto rats (WKY), SHR, and SHR treated with losartan (20 mg. kg-1. d-1) during 14 weeks before death. The expression of p53 and Bax proteins was assessed by Western blot analysis. The expression of BAX mRNA was assessed by Northern blot analysis. The density of apoptotic cells was assessed by direct immunoperoxidase detection of biotin-labeled deoxyuridine nucleotides. Compared with WKY, untreated SHR exhibited increased apoptosis (P<0.05), increased Bax-alpha protein (P<0.05), and similar levels of p53 protein and BAX mRNA. Losartan given long term was associated with the normalization of apoptosis and Bax-alpha protein expression. The expression of BAX mRNA was decreased (P<0. 05) in treated SHR compared with untreated SHR. No changes in the expression of p53 protein were observed in losartan-treated SHR. These results suggest that overexpression of the Bax-alpha protein seen in the left ventricle of adult SHR with increased apoptosis is not related to a p53-mediated upregulation of BAX gene transcription. Our data also suggest that normalization of Bax-alpha protein observed in SHR after long-term blockade of angiotensin II type 1 receptors may be due to the inhibition of BAX gene transcription.

Identification and characterization of alcR, a gene encoding an AraC-like regulator of alcaligin siderophore biosynthesis and transport in Bordetella pertussis and Bordetella bronchiseptica.

A Bordetella bronchiseptica iron transport mutant was isolated following an enrichment procedure based on streptonigrin resistance. The mutant displayed a growth defect on iron-restricted medium containing ferric alcaligin as the sole iron source. In addition to the apparent inability to acquire iron from the siderophore, the mutant failed to produce alcaligin as well as two known iron-regulated proteins, one of which is the AlcC alcaligin biosynthesis protein. A 1.6-kb KpnI-PstI Bordetella pertussis DNA fragment mapping downstream of the alcaligin biosynthesis genes alcABC restored both siderophore biosynthesis and expression of the iron-regulated proteins to the mutant. Nucleotide sequencing of this complementing 1.6-kb region identified an open reading frame predicted to encode a protein with strong similarity to members of the AraC family of transcriptional regulators, for which we propose the gene designation alcR. Primer extension analysis localized an iron-regulated transcription initiation site upstream of the alcR open reading frame and adjacent to sequences homologous to the consensus Fur repressor binding site. The AlcR protein was produced by using an Escherichia coli expression system and visualized in electrophoretic gels. In-frame alcR deletion mutants of B. pertussis and B. bronchiseptica were constructed, and the defined mutants exhibited the alcR mutant phenotype, characterized by the inability to produce and transport alcaligin and express the two iron-repressed proteins. The cloned alcR gene provided in trans restored these siderophore system activities to the mutants. Together, these results indicate that AlcR is involved in the regulation of Bordetella alcaligin biosynthesis and transport genes and is required for their full expression.

Identification and characterization of iron-regulated Bordetella pertussis alcaligin siderophore biosynthesis genes.

Bordetella bronchiseptica mutants BRM1, BRM6, and BRM9 fail to produce the native dihydroxamate siderophore alcaligin. A 4.5-kb BamHI-Smal Bordetella pertussis genomic DNA fragment carried multiple genes required to restore alcaligin production to these siderophore-deficient mutants. Phenotypic complementation analysis using subclones of the 4.5-kb genomic region demonstrated that the closely linked BRM1 and BRM9 mutations were genetically separable from the BRM6 mutation, and both insertions exerted strong polar effects on expression of the downstream gene defined by the BRM6 mutation, suggesting a polycistronic transcriptional organization of these alcaligin biosynthesis genes. Subcloning and complementation experiments localized the putative Bordetella promoter to a 0.7-kb BamHI-SphI subregion of the cloned genomic DNA fragment. Nucleotide sequencing, phenotypic analysis of mutants, and protein expression by the 4.5-kb DNA fragment in Escherichia coli suggested the presence of three alcaligin system genes, namely, alcA, alcB, and alcC. The deduced protein products of alcA, alcB, and alcC have significant primary amino acid sequence similarities with known microbial siderophore biosynthesis enzymes. Primer extension analysis mapped the transcriptional start site of the putative alcaligin biosynthesis operon containing alcABC to a promoter region overlapping a proposed Fur repressor-binding site and demonstrated iron regulation at the transcriptional level.

Specific IgG4 responses during chronic and transient antigen exposure in aspergillosis.

The factors that lead to increased production of specific IgG subclasses are still largely unknown. Recent studies suggest that increased IgG4 responses may be related to prolonged antigen exposure. We present data showing that increased IgG4 responses are found under conditions of chronic exposure to Aspergillus fumigatus (Af) antigen. IgG(total), IgG subclass, and IgE responses were studied using ELISA, CAP-FEIA, and immunoblotting techniques in patients with pulmonary aspergilloma (PA), which is a model for chronic antigen exposure, and allergic bronchopulmonary aspergillosis (ABPA), characterized by transient antigen exposure. Af-IgG1 was increased in patients with PA compared with those with ABPA. Patients with PA and IgE responses to Af and/or other inhalant allergens showed significantly higher Af-IgG4 responses than did patients with PA and negative IgE responses or patients with ABPA. Surveillance studies over time in individual patients showed concordance in Af-IgG1 and Af-IgG4 responses. Both Af-IgG1 and Af-IgG4 levels followed the course of disease progression and treatment. Immunoblotting revealed correlations between Af-IgG1 and Af-IgG4 binding to most, but not all, antigenic Af components. This study documents for the first time increased IgG4 levels under conditions of chronic exposure to fungal antigen in PA. Furthermore, a significantly higher IgG4 response was found in those patients with PA who produced IgE. The transient exposure to Af antigen during exacerbation of ABPA gives rise to transient elevations in IgG4 levels.

The role of bronchoscopic therapy in bronchial granular cell myoblastoma: presentation of three cases.

Tracheobronchial granular cell myoblastoma (GCM) is rare. Although the tumor has some malignant properties, it is considered benign, and there is no consensus regarding treatment. Three cases are reported here. Bronchoscopic treatment in patients with GCM may be attempted as a first approach in case the tumor is intraluminal.

A new photoconductor imaging system for digital radiography.

Amorphous selenium is a material often used in the x-ray imaging system. The main application is in xeroradiography where the structure of the sensor is a layer of selenium on a conductive substrate. The signal is a charge density on the surface which is revealed by a toner or by electrostatic probe for digitalization. In the system described here, the sensor structure is different for the sensor is covered by an electrode, a thin layer of metal, which gives another interface. The reading system needs the scanning of a light beam and the resolution power depends on the size of the beam. It is easier to scan a light beam than electrostatic probes so a more compact system can be realized. In the process, there are two phases: the storage and the reading. The time spent between the two phases reduces the quality of the image, and an in situ reading system, integrated to the radiographic machine will be, for this reason, more efficient. Also, the sensor needs good memory effect. One has investigated different sensors based on a structure of a thin photoconductive layer between two electrodes to find a memory effect. We have already seen this phenomena in the Bi12 SiO20 (B. Richard, "Contribution à l'étude d'un procédé d'imagerie radiologique utilisant le photoconducteur BO12 SiO20," Ph.D. thesis, Paris, 1987). In amorphous selenium with some dopants and some type of metallic contact, the memory effect is important enough to realize a system. With 2 X 2 cm samples, a complete x-ray digital imaging system has been built.(ABSTRACT TRUNCATED AT 250 WORDS)