Spontaneous healing and scar control following enzymatic debridement of deep second-degree burns.

Scarring after a burn injury remains the greatest unmet challenge in the treatment of functional and psychosocial sequelae of burns. The hypertrophic scar represents the most common type of cicatrix after burns, and it has a prevalence of up to 70%. We present a case of upper and lower extremity partial-thickness burns in a female patient treated in two different modalities. Superficial seconddegree burns on the upper extremities were treated with conservative dressing with fairly early wound closure but they developed hypertrophic scars. Deeper, lower extremity burns were debrided with a new bromelain-based debriding agent, resulting in scar-free healing. The pathophysiology of hypertrophic scar formation is based on the perturbation of collagen production or degradation or both. The duration and magnitude of the inflammatory phase of wound healing also appears to play a role in hypertrophic scarring. Bromelain has demonstrated an anti-angiogenic effect in various cancer cell lines and it has been shown to regulate a variety of pro-angiogenic growth factors. This case raises the classical question of the relationship between time to healing and formation of hypertrophic scars after burn injury, pointing to other potential factors that may play an important role in burn healing.

La cicatrisation après une brûlure reste le plus grand défi du traitement des séquelles à la fois sur le plan fonctionnel et sur le plan psychologique. La cicatrisation hypertrophique représente l'évolution la plus fréquente après brûlure et sa prévalence est supérieure à 70 %. Nous présentons une observation de brûlures du 2e degré au niveau du membre supérieur et du membre inférieur chez une patiente traitée suivant deux modalités différentes. Les brûlures du second degré superficiel du membre supérieur furent traitées par un pansement classique avec une cicatrisation précoce, mais suivie de cicatrices hypertrophiques. Les brûlures plus profondes du membre inférieur furent détergées avec le nouvel agent à base de bromelaïne, et permirent une guérison sans cicatrice. La physiopathologie de la cicatrisation hypertrophique est basée sur les troubles de production des fibres de collagène, ou de leur dégradation, ou des deux. La durée et l'amplitude de la phase inflammatoire de la cicatrisation paraît aussi jouer un rôle dans l'hypertrophie cicatricielle. La bromelaïne a démontré son effet anti-angiogénique dans plusieurs lignées cellulaires cancéreuses ; elle a montré aussi son aptitude à réguler les divers facteurs de croissance pro-angiogéniques. Cette observation soulève la question classique de la relation entre le temps de cicatrisation et l'apparition de cicatrices hypertrophiques après brûlure, en soulignant les autres facteurs potentiels jouant un rôle important dans la cicatrisation des brûlures.

Use of the Wasserman equation in optimization of the duration of the power ramp in a cardiopulmonary exercise test: a study of Brazilian men

This study aimed to analyze the agreement between measurements of unloaded oxygen uptake and peak oxygen uptake based on equations proposed by Wasserman and on real measurements directly obtained with the ergospirometry system. We performed an incremental cardiopulmonary exercise test (CPET), which was applied to two groups of sedentary male subjects: one apparently healthy group (HG, n=12) and the other had stable coronary artery disease (n=16). The mean age in the HG was 47±4 years and that in the coronary artery disease group (CG) was 57±8 years. Both groups performed CPET on a cycle ergometer with a ramp-type protocol at an intensity that was calculated according to the Wasserman equation. In the HG, there was no significant difference between measurements predicted by the formula and real measurements obtained in CPET in the unloaded condition. However, at peak effort, a significant difference was observed between oxygen uptake (V˙O2)peak(predicted)and V˙O2peak(real)(nonparametric Wilcoxon test). In the CG, there was a significant difference of 116.26 mL/min between the predicted values by the formula and the real values obtained in the unloaded condition. A significant difference in peak effort was found, where V˙O2peak(real)was 40% lower than V˙O2peak(predicted)(nonparametric Wilcoxon test). There was no agreement between the real and predicted measurements as analyzed by Lin’s coefficient or the Bland and Altman model. The Wasserman formula does not appear to be appropriate for prediction of functional capacity of volunteers. Therefore, this formula cannot precisely predict the increase in power in incremental CPET on a cycle ergometer.

Use of the Wasserman equation in optimization of the duration of the power ramp in a cardiopulmonary exercise test: a study of Brazilian men.

This study aimed to analyze the agreement between measurements of unloaded oxygen uptake and peak oxygen uptake based on equations proposed by Wasserman and on real measurements directly obtained with the ergospirometry system. We performed an incremental cardiopulmonary exercise test (CPET), which was applied to two groups of sedentary male subjects: one apparently healthy group (HG, n=12) and the other had stable coronary artery disease (n=16). The mean age in the HG was 47±4 years and that in the coronary artery disease group (CG) was 57±8 years. Both groups performed CPET on a cycle ergometer with a ramp-type protocol at an intensity that was calculated according to the Wasserman equation. In the HG, there was no significant difference between measurements predicted by the formula and real measurements obtained in CPET in the unloaded condition. However, at peak effort, a significant difference was observed between oxygen uptake (V˙O2)peak(predicted)and V˙O2peak(real)(nonparametric Wilcoxon test). In the CG, there was a significant difference of 116.26 mL/min between the predicted values by the formula and the real values obtained in the unloaded condition. A significant difference in peak effort was found, where V˙O2peak(real)was 40% lower than V˙O2peak(predicted)(nonparametric Wilcoxon test). There was no agreement between the real and predicted measurements as analyzed by Lin's coefficient or the Bland and Altman model. The Wasserman formula does not appear to be appropriate for prediction of functional capacity of volunteers. Therefore, this formula cannot precisely predict the increase in power in incremental CPET on a cycle ergometer.

Realizing solar power's potential in the European Union.

The European Union aims at largely decarbonizing its energy system by 2050. In this context, this paper reviews the status of the solar electricity technologies that can exploit our largest renewable energy resource. Although substantial progress is being made, the possibility, for instance, to more than double the efficiency of photovoltaic systems underlines the continued need for coordinated R&D efforts, aimed also at promoting European expertise and industrial competiveness. In parallel, it is important to expand the market by developing integrated building products and by demonstrating the viability of very large scale systems for both technologies.

Multiband superconductivity in the Chevrel phases SnMo6S8 and PbMo6S8.

Sub-Kelvin scanning tunneling spectroscopy in the Chevrel phases SnMo6S8 and PbMo6S8 reveals two distinct superconducting gaps with Δ1=3 meV, Δ2∼1.0 meV and Δ1=3.1 meV, Δ2∼1.4 meV, respectively. The gap distribution is strongly anisotropic, with Δ2 predominantly seen when scanning across unit-cell steps on the (001) sample surface. The spectra are well fitted by an anisotropic two-band BCS s-wave gap function. Our spectroscopic data are confirmed by electronic heat capacity measurements, which also provide evidence for a twin-gap scenario.

Application of modern online instrumentation for chemical analysis of gas and particulate phases of exhaust at the European Commission heavy-duty vehicle emission laboratory.

The European Commission recently established a novel test facility for heavy-duty vehicles to enhance more sustainable transport. The facility enables the study of energy efficiency of various fuels/scenarios as well as the chemical composition of evolved exhaust emissions. Sophisticated instrumentation for real-time analysis of the gas and particulate phases of exhaust has been implemented. Thereby, gas-phase characterization was carried out by a Fourier transform infrared spectrometer (FT-IR; carbonyls, nitrogen-containing species, small hydrocarbons) and a resonance-enhanced multiphoton ionization time-of-flight mass spectrometer (REMPI-TOFMS; monocyclic and polycyclic aromatic hydrocarbons). For analysis of the particulate phase, a high-resolution time-of-flight aerosol mass spectrometer (HR-TOF-AMS; organic matter, chloride, nitrate), a condensation particle counter (CPC; particle number), and a multiangle absorption photometer (MAAP; black carbon) were applied. In this paper, the first application of the new facility in combination with the described instruments is presented, whereby a medium-size truck was investigated by applying different driving cycles. The goal was simultaneous chemical characterization of a great variety of gaseous compounds and particulate matter in exhaust on a real-time basis. The time-resolved data allowed new approaches to view the results; for example, emission factors were normalized to time-resolved consumption of fuel and were related to emission factors evolved during high speeds. Compounds could be identified that followed the fuel consumption, others showed very different behavior. In particular, engine cold start, engine ignition (unburned fuel), and high-speed events resulted in unique emission patterns.

Chemical characterization of emissions from modern two-stroke mopeds complying with legislative regulation in Europe (EURO-2).

In view of a new amendment to the European legislative regulation on emissions from two-stroke mopeds a study was carried out to comprehensively characterize exhaust gases of mopeds complying current EURO-2 emission standards. Three mopeds with different engine types (carburetor, direct injection, and electronic carburetion system ECS) where investigated by applying two different driving cycles, the legislative cycle ECE47 and the worldwide motorcycle test cycle WMTC. Thereby, particulate matter (PM), regulated compounds, carbonyls, volatile hydrocarbons (VOC), and particle-associated polyaromatic hydrocarbons (PAH) were analyzed and ozone formation potentials (OFP) as well as toxicity equivalents (TEQ) determined. The ECE47 emission factors for almost all species and moped types were much higher in the nonregulated, prior cold phase than in the hot phase, which is considered for legislation. Great differences for the mopeds could be observed for NO(x), VOC, and PM, whereas discrepancies between the driving cycles ECE47 and WMTC were smaller. In addition, a positive influence on exhaust composition caused by technical modifications of the ECS engine was determined. Results indicate that regulation of total hydrocarbons (THC) alone might not be sufficient to regulate PM, especially for direct injection engines. Moreover, recommendations for a revised future test protocol are demonstrated and discussed, whereby the cold phase and the hot phase are taken into account.

Oesophagitis dissecans superficialis: an acute, benign phenomenon associated with pemphigus vulgaris.

Pemphigus vulgaris (PV) is an autoimmune dermatosis that may evolve to severely compromise the skin and/or mucosa. Autoantibodies directed against epithelial cadherins, such as desmogleins 1 and 3, lead to acantholysis and culminate in blister formation. Involvement of the oral mucosa is common, but other squamous stratified epithelia may also be the target of the autoimmune aggression. We report a woman with PV that was in partial remission, who developed an unusual acute phenomenon, known as oesophagitis dissecans superficialis.

Study of the Fermi surface of ZrB12 using the de Haas-van Alphen effect.

The de Haas-van Alphen (dHvA) effect in the cluster superconductor ZrB12 was studied by magnetic torque measurements in magnetic fields up to 28 T at temperatures down to 0.07 K. The dHvA oscillations due to orbits from the neck sections and "cubic box" of the Fermi surface were detected. The dHvA frequencies as well as the cyclotron effective masses were calculated using the full-potential linear muffin-tin orbitals method within the generalized gradient approximation. A comparison of the experimental and calculated cyclotron mass shows unusually large electron-phonon interaction on the neck (lambdaep=0.95) and box (lambdaep=1.07) sections of the Fermi surface on the Brillouin zone boundaries.

Scanning tunneling spectroscopy in the superconducting state and vortex cores of the beta-pyrochlore KOs2O6.

We performed the first scanning tunneling spectroscopy measurements on the pyrochlore superconductor KOs2O6 (T(c)=9.6 K) in both zero magnetic field and the vortex state at several temperatures above 1.95 K. This material presents atomically flat surfaces, yielding spatially homogeneous spectra which reveal fully gapped superconductivity with a gap anisotropy of 30%. Measurements performed at fields of 2 and 6 T display a hexagonal Abrikosov flux line lattice. From the shape of the vortex cores, we extract a coherence length of 31-40 A, in agreement with the value derived from the upper critical field H(c2). We observe a reduction in size of the vortex cores (and hence the coherence length) with increasing field which is consistent with the unexpectedly high and unsaturated upper critical field reported.

An integrated approach to assess the PCDD/F emissions of the coal fired stoves combining emission measurements and ambient air levels modelling.

Very high emissions of PCDD/Fs up to 1300 microg TEQ per ton of coal were measured during combustion of commercial high chlorine content coal in a stove. A pronounced effect of the temperature profile in the chimney on PCDD/F emissions was identified, suggesting formation in the chimney. Emissions of PCDD/Fs were one order of magnitude higher with an insulated chimney than with a non-insulated one. Insulation of the chimney did not influence the emissions of regulated pollutants and PAHs. Under laboratory conditions, the thermal properties of the chimney usually differ from those in residential dwellings. For that reason it is concluded that PCDD/F emission measurements performed under laboratory conditions may not be representative for derivation of emission factors in emission inventory compilations. Thus the emission factor of 1300 microg TEQ per ton of coal (40000 microg TEQ/TJ) represents the maximum value for individual stove emissions. Complementary air dispersion modelling and congener profile based receptor modelling performed in the Krakow area, Poland confirm a high contribution of the residential combustion to the ambient air PCDD/F levels in that area and indicate an emission factor for coal combustion in stoves in the order of 100 microg TEQ per ton (3000 microg TEQ/TJ).

[Feasibility and reliability of the study of sentinel lymph nodes with immunohistochemical technique in colonic carcinoma]. / Fattibilità e accuratezza dello studio del linfonodo sentinella con tecnica immunoistochimica nel carcinoma del colon.

Sentinel lymph node sampling, in patients with resectable colon cancer, improved identification of lymph node disease and identified patients likely to benefit from adjuvant therapy. This study examined whether sentinel node sampling accurately predicted lymph node status for patients with resectable colon cancer.

Direct observation of the multisheet Fermi surface in the strongly correlated transition metal compound ZrZn2.

The existence of flat areas of a Fermi surface (FS), predicted by electronic structure calculations and used in models of both magnetically mediated and phonon-mediated Fulde-Ferrell-Larkin-Ovchinnikov superconducting states, is reported in the paramagnetic phase of the ferromagnetic superconductor ZrZn2 using positron annihilation. The strongly mass-renormalized FS sheet, dominating the Fermi level density of states, is seen for the first time. The delocalization of the magnetization is studied using measured and calculated magnetic Compton profiles.

Heavy quasiparticles in the ferromagnetic superconductor ZrZn2.

We report a study of the de Haas-van Alphen effect in the normal state of the ferromagnetic superconductor ZrZn2. Our results are generally consistent with a linear muffin-tin orbital band structure which predicts four exchange-split Fermi surface sheets. Quasiparticle effective masses are enhanced by a factor of 4.9 implying a strong coupling to magnetic excitations or phonons. ZrZn2 is unique among metallic ferromagnets in that it has a very large density of states in the ferromagnetic phase.

Longitudinal spin fluctuations and superconductivity in ferromagnetic ZrZn2 from Ab initio calculations.

The recent discovery of superconductivity coexisting with weak itinerant ferromagnetism in the d-electron intermetallic compound ZrZn2 strongly suggests spin-fluctuation mediated superconductivity. Ab initio electronic structure calculations of the Fermi surface and generalized susceptibilities are performed to investigate the viability of longitudinal spin-fluctuation-induced spin-triplet superconductivity in the ferromagnetic state. The critical temperature is estimated to be of the order of 1 K. Additionally, it is shown that in spite of a strong electron-phonon coupling ( lambda(ph) = 0.7), conventional s-wave superconductivity is inhibited by the presence of strong spin fluctuations.

[Varicocele in young recruits]. / Il varicocele nei giovani di leva.

The authors, after an examination of the literature on the subject, present the results of a retrospective study in which the incidence of varicocele among selected young soldiers population called up at SARVAM (Viterbo) from May 1993 until October 1995 is evaluated.

Circulating endothelin-1 in non-insulin-dependent diabetic patients with retinopathy.

Endothelin-1 (ET-1), a novel 21-amino acid vasoconstrictive peptide secreted by endothelial cells, has been thought to play a role in various forms of vascular disease. Diabetes mellitus is well known for its association with microvascular damage. To investigate whether ET-1 levels may be related to microangiopathy in diabetes mellitus, plasma ET-1 levels were measured in two groups of diabetic patients: A) 47 patients with non-insulin dependent diabetes mellitus (NIDDM) and retinopathy (28 M, 19 F; mean age 60.7+/-8.5 yrs) but without nephropathy (microalbuminuria < 30 mg/day) and hypertension (SBP < 140, DBP < 90 mmHg); group A was divided in three subgroups based on the severity of retinopathy: a) 16 with background retinopathy; b) 21 with pre-proliferative retinopathy; c) 10 with proliferative retinopathy. B) 8 patients with insulin-dependent diabetes mellitus (IDDM) recently diagnosed (6 M, 2 F; 16.4+/-3.8 yrs) without complications. C) 28 healthy subjects (HS) (16 M, 12 F; 47.8+/-11.8 yrs) as controls. In the NIDDM group the ET-1 concentration was significantly higher (17.3+/-2.4 pg/ml) than both in the HS (8+/-4.7 pg/ml) and IDDM patients (10.2+/-3.7 pg/ml) (p < 0.0001). In the subgroups with retinopathy the ET-1 levels were a) 15.1+/-4.3 pg/ml; b) 22.2+/-6.8 pg/ml and c) 16.6+/-5.1 pg/ml. These values were significantly elevated as compared to HS (p<0.001; p < 0.0001; p < 0.002, respectively), being the highest levels of ET-1 observed in the NIDDM patients with pre-proliferative retinopathy. In conclusion our study revealed that the ET-1 concentrations are elevated in NIDDM patients with retinopathy especially in those patients with pre-proliferative retinopathy.

[In vitro effects of IL-2 on human hypophyseal adenoma]. / Effetti in vitro della IL-2 su adenomi ipofisari umani.

The effects of two different concentrations of IL-2 on human pituitary adenomas (one secreting ACTH and one secreting GH) were evaluated in vitro. A specimen of the tumor was dissagregated and the cells were incubated for three days with RPMI 1640 medium. The medium was then decanted and the cells were incubated with 1 mlo of fresh medium for three hours and then with new fresh medium containing two different concentrations of IL-2, 100U/ml, for three hours too. The pituitary hormones, ACTH and GH, released into the medium were assayed by RIA. Dose of 100 U IL-2 induced a profound increase of ACTH release. The other dose decreased ACTH release. The release of GH was suppressed by IL-2 at the two concentrations tested. IL-2 may be an immunologic messenger exerting direct action at pituitary level. It appears probable that IL-2 plays an important role in determining the response of the pituitary to stress and infections.