Cooling Holstein cows for 60 days prepartum in summer: effects on prepartum physiology, postpartum productivity, and calf growth.

Heat stress (HS) during the dry period of dairy cows in hot and dry conditions compromises the physiological status and mammary gland development of dairy cows, thereby negatively affecting milk component yield in the subsequent lactation. Our objective was to evaluate the effects of cooling Holstein cows under moderate or higher HS conditions (i.e., ambient temperature higher than 30 °C, with a temperature-humidity index of 78.2 units) during the dry period on prepartum physiological status, postpartum productivity, and calf growth. Twenty-four multiparous Holstein cows were divided into two groups: one with a cooling system based on spray and fans under a pen shade (CL, n = 12) and the other not-cooled (NC, n = 12). The cooling system operated 10 h/d (09:00-19:00 h) for 60 d prepartum. During the morning, rectal temperature and respiration frequency were lower in CL cows, but not in the afternoon, which was attributed to higher (P < 0.01) dry matter intake by CL cows. Total serum protein was higher (P < 0.01) in CL cows, but hemoglobin was higher in NC cows (P < 0.01), with no differences in other electrolytes, hormones, hematological components, and metabolites. Milk fat and fat and fat-protein corrected milk were higher (P < 0.05) in CL cows. Female and birth weight trended (P = 0.08) to be higher in CL cows. Cooling cows during the dry period had a limited effect on physiology prepartum but increased postpartum productivity of Holstein cows under hot and dry conditions.

Predicting carcass tissue composition in Blackbelly sheep using ultrasound measurements and machine learning methods.

This study aimed to predict Blackbelly sheep carcass tissue composition using ultrasound measurements and machine learning models. The models evaluated were decision trees, random forests, support vector machines, and multi-layer perceptrons and were used to predict the total carcass bone (TCB), total carcass fat (TCF), and total carcass muscle (TCM). The best model for predicting the three parameters, TCB, TCF, and TCM was random forests, with mean squared error (MSE) of 0.31, 0.33, and 0.53; mean absolute error (MAE) of 0.26, 0.29, and 0.53; and the coefficient of determination (R2) of 0.67, 0.69, and 0.76, respectively. The results showed that machine learning methods from in vivo ultrasound measurements can be used as determinants of carcass tissue composition, resulting in reliable results.

Reproductive performance of hair ewes and rams implanted with melatonin previous to the anestrus season in northwest Mexico.

Ovine reproductive behavior depends on annual photoperiodic cycle and its impact on endogenous melatonin secretion. In this regard, exogenous melatonin administration previous to the physiological anestrus period could modify the reproductive performance of sheep in the northwest of Mexico. Two independent studies were performed to evaluate such hypothesis in hair sheep implanted with melatonin prior to the anestrus season in latitudes 24° and 25° of Mexico. Study 1 involved 15 rams assigned to one of three treatments receiving 0mg (n=5), 18mg (n=5), or 36mg (n=5) of melatonin subcutaneously. Study variables were measured monthly since implantation (d0) and included testosterone concentration, scrotal circumference, mass motility, individual motility, and sperm concentration. Study 2 included 50 ewes assigned to one of two treatments receiving 0mg (n=25) or 18mg (n=25) of melatonin subcutaneously. In ewes, progesterone concentration and the frequency of females in anestrus were measured during the implantation (-30d), as well as at the beginning (0d) and at the end (45d) of the mating period, while pregnancy rate was determined by ultrasonography 45d after. Continuous variables were analyzed using a mixed effects model considering treatment, time, and the treatment by time interaction as fixed effects. Animal nested within treatment was the random effect. Binary variables were analyzed using the chi-square test. In males, melatonin improved testosterone and sperm concentrations (P<0.05), while in females, a 28% higher pregnancy rate was observed in implanted ewes (P<0.05). Therefore, melatonin enhanced reproductive parameters in both sexes and its exogenous administration previous to the anestrus season in northwest Mexico could be more effective in rams.

Estimation of Carcass Tissue Composition from the Neck and Shoulder Composition in Growing Blackbelly Male Lambs.

This study was designed to develop predictive equations estimating carcass tissue composition in growing Blackbelly male lambs using as predictor variables for tissue composition of wholesale cuts of low economic value (i.e., neck and shoulder). For that, 40 lambs with 29.9 ± 3.18 kg of body weight were slaughtered and then the left half carcasses were weighed and divided in wholesale cuts, which were dissected to record weights of fat, muscle, and bone from leg, loin, neck, rib, and shoulder. Total weights of muscle (CM), bone (CB) and fat (CF) in carcass were recorded by adding the weights of each tissue from cuts. The CM, CF and CB positively correlated (p < 0.05; 0.36 ≤ r ≤ 0.86), from moderate to high, with most of the shoulder tissue components, but it was less evident (p ≤ 0.05; 0.32≤ r ≤0.63) with the neck tissue composition. In fact, CM did not correlate with neck fat and bone weights. Final models explained (p < 0.01) 94, 92 and 88% of the variation observed for CM, CF and CB, respectively. Overall, results showed that prediction of carcass composition from shoulder (shoulder) tissue composition is a viable option over the more accurate method of analyzing the whole carcass.

Robust Nonequilibrium Edge Currents with and without Band Topology.

We study two-dimensional bosonic and fermionic lattice systems under nonequilibrium conditions corresponding to a sharp gradient of temperature imposed by two thermal baths. In particular, we consider a lattice model with broken time-reversal symmetry that exhibits both topologically trivial and nontrivial phases. Using a nonperturbative Green function approach, we characterize the nonequilibrium current distribution in different parameter regimes. For both bosonic and fermionic systems, we find chiral edge currents that are robust against coupling to reservoirs and to the presence of defects on the boundary or in the bulk. This robustness not only originates from topological effects at zero temperature but, remarkably, also persists as a result of dissipative symmetries in regimes where band topology plays no role. Chirality of the edge currents implies that energy locally flows against the temperature gradient without any external work input. In the fermionic case, there is also a regime with topologically protected boundary currents, which nonetheless do not circulate around all system edges.

Rheological and Tribological Properties of Nanocellulose-Based Ecolubricants.

Based on the response surface methodology, a rheological and tribological study carried out on eco-friendly lubricants is described. Such ecolubricants consisted of fibrillated or crystalline nanocellulose in vegetable oil (castor oil, high oleic sunflower oil or their mixtures). Cellulose nanoparticles showed noticeable friction-reducing and anti-wear properties within the boundary and mixed lubrication regimes, which were found to be dependent on nanocellulose concentration, base oil composition and applied normal force. In general, both types of nanocellulose performed equally well. An excellent tribological performance, with large wear scar diameter reductions, was achieved with 3.3 wt.% (or higher) nanocellulose dispersions in castor oil-rich mixtures. The observed behavior was explained on the basis of enhanced viscosity of castor oil-rich suspensions and the preferential action of the most polar components, nanocellulose and ricinoleic acid, in the vicinity of the contact surfaces.

Trusted Cameras on Mobile Devices Based on SRAM Physically Unclonable Functions.

Nowadays, there is an increasing number of cameras placed on mobile devices connected to the Internet. Since these cameras acquire and process sensitive and vulnerable data in applications such as surveillance or monitoring, security is essential to avoid cyberattacks. However, cameras on mobile devices have constraints in size, computation and power consumption, so that lightweight security techniques should be considered. Camera identification techniques guarantee the origin of the data. Among the camera identification techniques, Physically Unclonable Functions (PUFs) allow generating unique, distinctive and unpredictable identifiers from the hardware of a device. PUFs are also very suitable to obfuscate secret keys (by binding them to the hardware of the device) and generate random sequences (employed as nonces). In this work, we propose a trusted camera based on PUFs and standard cryptographic algorithms. In addition, a protocol is proposed to protect the communication with the trusted camera, which satisfies authentication, confidentiality, integrity and freshness in the data communication. This is particularly interesting to carry out camera control actions and firmware updates. PUFs from Static Random Access Memories (SRAMs) are selected because cameras typically include SRAMs in its hardware. Therefore, additional hardware is not required and security techniques can be implemented at low cost. Experimental results are shown to prove how the proposed solution can be implemented with the SRAM of commercial Bluetooth Low Energy (BLE) chips included in the communication module of the camera. A proof of concept shows that the proposed solution can be implemented in low-cost cameras.

VLSI Design of Trusted Virtual Sensors.

This work presents a Very Large Scale Integration (VLSI) design of trusted virtual sensors providing a minimum unitary cost and very good figures of size, speed and power consumption. The sensed variable is estimated by a virtual sensor based on a configurable and programmable PieceWise-Affine hyper-Rectangular (PWAR) model. An algorithm is presented to find the best values of the programmable parameters given a set of (empirical or simulated) input-output data. The VLSI design of the trusted virtual sensor uses the fast authenticated encryption algorithm, AEGIS, to ensure the integrity of the provided virtual measurement and to encrypt it, and a Physical Unclonable Function (PUF) based on a Static Random Access Memory (SRAM) to ensure the integrity of the sensor itself. Implementation results of a prototype designed in a 90-nm Complementary Metal Oxide Semiconductor (CMOS) technology show that the active silicon area of the trusted virtual sensor is 0.86 mm 2 and its power consumption when trusted sensing at 50 MHz is 7.12 mW. The maximum operation frequency is 85 MHz, which allows response times lower than 0.25 µ s. As application example, the designed prototype was programmed to estimate the yaw rate in a vehicle, obtaining root mean square errors lower than 1.1%. Experimental results of the employed PUF show the robustness of the trusted sensing against aging and variations of the operation conditions, namely, temperature and power supply voltage (final value as well as ramp-up time).

Modification of Alkali Lignin with Poly(Ethylene Glycol) Diglycidyl Ether to Be Used as a Thickener in Bio-Lubricant Formulations.

Considerable efforts are currently being made by the academic community and industry, aiming to develop environmentally friendly lubricants with suitable technical features for their performance. In this context, lignin could be considered a promising candidate to be used as a bio-sourced thickening agent to formulate eco-friendly lubricating greases. In this work, alkali lignin (AL) was chemically modified with poly(ethylene glycol) diglycidyl ether (PEGDE). Afterwards, the epoxidized lignin was properly dispersed in castor oil (CO) in order to obtain an oleogel for lubricant applications. The epoxidized lignins were characterized by means of epoxy index determination, thermogravimetric analysis (TGA) and Fourier transform infrared (FTIR) spectroscopy. The epoxide-functionalized lignin-based oleogels were analyzed from both rheological and tribological points of view. It was found that the viscosity, consistency and viscoelastic functions of these oleogels clearly increased with the epoxy index of the epoxide-modified lignin compound. Thermo-rheological characterization of these oleogels revealed a slight thermal dependence of the viscoelastic moduli below 100 °C, but a significant softening above that critical temperature. In general, these oleogels showed low values of the friction coefficient under the mixed lubrication regime as compared to the neat castor oil.

Topological Heat Transport and Symmetry-Protected Boson Currents.

The study of non-equilibrium properties in topological systems is of practical and fundamental importance. Here, we analyze the stationary properties of a two-dimensional bosonic Hofstadter lattice coupled to two thermal baths in the quantum open-system formalism. Novel phenomena appear like chiral edge heat currents that are the out-of-equilibrium counterparts of the zero-temperature edge currents. They support a new concept of dissipative symmetry-protection, where a set of discrete symmetries protects topological heat currents, differing from the symmetry-protection devised in closed systems and zero-temperature. Remarkably, one of these currents flows opposite to the decreasing external temperature gradient. As the starting point, we consider the case of a single external reservoir already showing prominent results like thermal erasure effects and topological thermal currents. Our results are experimentally accessible with platforms like photonics systems and optical lattices.

Natural and synthetic antioxidant additives for improving the performance of new biolubricant formulations.

Knowledge of the oxidative stability of vegetable oils for lubricant applications is a key point, because vegetable oil oxidation potential is the main disadvantage for its use as a lubricant. Oil degradation after an oxidation process can seriously affect its lubricating function and increase wear. In this work, two different methods for evaluating the oxidation stability of lubricating vegetable oils, the oxidation onset temperature, characterized through DSC measurements (ASTM E 2009-08), and the pressure drop in the oxygen pressure vessel (ASTM D 942-02), have been used. Additionally, thermogravimetric analysis and FTIR studies have also been carried out. High-oleic sunflower (HOSO) and castor (CO) oils were selected and blended with natural ((+)-α-tocopherol (TCP), propyl gallate (PG), l-ascorbic acid 6-palmitate (AP)) or synthetic antioxidants (4,4'-methylenebis(2,6-di-tert-butylphenol) (MBP)), with the aim of formulating biodegradable vegetable-based lubricants according to REACH regulation. (1) The results showed that the most effective biodegradable antioxidant is PG, comparable to MBP, whereas lower effectiveness was obtained for TCP and AP. In relation to the methods tested, DSC measurements achieve accurate data more quickly for evaluating the oxidation stability of these basestocks, showing a linear correlation with the traditional method based on the oxygen bomb test. The empirical equation obtained depends on the mechanism involved in the antioxidant activity.

Determination of quinolone residues in infant and young children powdered milk combining solid-phase extraction and ultra-performance liquid chromatography-tandem mass spectrometry.

The present work describes a method based on solid-phase extraction (SPE) and ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) for the simultaneous determination of three quinolones (pipemidic acid, oxolinic acid and flumequine) and twelve fluoroquinolones (marbofloxacin, fleroxacin, pefloxacin, levofloxacin, norfloxacin, ciprofloxacin, enrofloxacin, danofloxacin, lomefloxacin, difloxacin, sarafloxacin, and moxifloxacin) in different infant and young children powdered milks. After suitable deproteination of the reconstituted powdered samples, a SPE procedure was developed providing recovery values higher than 84% (RSDs lower than 13%) for all the analytes, with limits of detection between 0.04 and 0.52 µg/kg. UPLC-MS/MS analyses were carried out in less than 10 min. Sixteen infant and young children powdered milk samples of different origin, type and composition bought at Spanish markets were analyzed. Residues of the selected antibiotics were not detected in any of the analyzed samples.

Dispersive liquid-liquid microextraction combined with nonaqueous capillary electrophoresis for the determination of fluoroquinolone antibiotics in waters.

Dispersive liquid-liquid microextraction (DLLME) was combined for the first time with NACE-UV for the selective determination of eight fluoroquinolone antibiotics (lomefloxacin, levofloxacin, marbofloxacin, ciprofloxacin, sarafloxacin, enrofloxacin, danofloxacin and difloxacin) in mineral and run-off waters. Field-enhanced sample injection was carried out in order to improve the sensitivity, whereas pipemidic acid was used as internal standard. The BGE that provided complete separation of the eight analytes and the internal standard was composed of 3 M acetic acid, 49 mM ammonium acetate in 55:45 v/v methanol:ACN. Optimum DLLME conditions (extraction of 5 mL of water at pH 7.6 with 685 µL of CHCl(3) and 1250 µL of ACN, extractant and disperser solvents, respectively) were achieved by means of experimental design methodology. Calibration curves of the whole method were obtained with correlation coefficients (R) higher than 0.994 in all cases. An accuracy and precision study was carried out at different levels of concentration, finding that there were no significant differences (Student's t-test) between real and spiked concentrations.

Levosimendan increases portal blood flow and attenuates intestinal intramucosal acidosis in experimental septic shock.

It has been proposed that vasodilatory therapy may increase microcirculatory blood flow and improve tissue oxygenation in septic shock. The authors aimed to evaluate the effects of levosimendan in systemic and splanchnic hemodynamics in a porcine model of septic shock in a randomized animal controlled study. This study was performed in an animal research facility in a university hospital. Anesthetized pigs were monitored with a pulmonary artery catheter and an ultrasonic blood flow probe in the portal vein for measurement of systemic and portal blood flows and with a tonometer placed in the small intestine for measurement of the intramucosal-arterial PCO2 gap. Three groups of pigs were studied: nonseptic (n = 7), septic (n = 7), and septic treated with levosimendan (n = 7). Levosimendan was administered i.v. at t = -10 min (200 microg/kg in i.v. bolus followed by 200 microg/kg per h). Sepsis was induced at t = 0 min by the administration of live Escherichia coli. Vascular reactivity was tested by the hemodynamic response to noradrenaline. Levosimendan markedly attenuated the sepsis-induced increase in pulmonary vascular resistance, decrease in portal/systemic blood flow, oliguria, impairment in oxygenation, hyperkalemia, and the widened intramucosal-arterial PCO2 gap. Systemic blood pressure and vascular resistance did not differ as compared with the septic untreated group. Responses to noradrenaline significantly improved in animals treated with levosimendan. Treatment with levosimendan in this animal model of sepsis attenuated pulmonary vasoconstriction and improved portal blood flow, intestinal mucosal oxygenation, pulmonary function, and vascular reactivity.

Multiple pesticide analysis in wine by MEKC combined with solid-phase microextraction and sample stacking.

In this work, a new method for the determination in white wines of 12 pesticides widely used in vine cultivars (namely, carbendazim, pirimicarb, metalaxyl, pyrimethanil, procymidone, nuarimol, azoxystrobin, tebufenozide, fenarimol, benalaxyl, penconazole, and tetradifon) using solid-phase microextraction (SPME) and MEKC with diode-array detection (DAD) was developed. The MEKC buffer consisted of 100 mM sodium tetraborate and 30 mM SDS at pH 8.5 with 6% v/v 1-propanol. Reversed-electrode polarity stacking mode (REPSM) was applied as on-line preconcentration strategy. In order to carry out an effective and sensitive determination of these pesticides in wine samples, an off-line SPME procedure was optimized by means of an experimental design. After studying the extraction performance of different SPME coatings, PDMS/divinylbenzene (PDMS/DVB) fibers were found the most appropriate for the extraction of most of these pesticides. Carbendazim and metalaxyl could not be extracted from wine samples. Calibration curves for extracted standards and fortified white wines were studied in order to determine the presence of a matrix effect. The combination of both preconcentration procedures (SPME and REPSM) allowed the determination of ten of these pesticides in white wines at concentrations between 0.054 and 0.113 mg/L. (i.e., levels well below the maximum residue limits (MRLs) allowed for these compounds in wine grapes). Ten homemade wines were they analyzed with the optimized method demonstrating the usefulness of the proposed procedure.

MEKC combined with SPE and sample stacking for multiple analysis of pesticides in water samples at the ng/L level.

In this work, a new multiresidue analytical method based on MEKC with UV detection combined with SPE as off-line preconcentration strategy, and reversed-electrode polarity stacking mode (REPSM) as on-line stacking procedure, has been developed for the monitoring of 12 pesticides (carbendazim, pirimicarb, metalaxyl, pyrimethanil, procymidone, nuarimol, azoxystrobin, tebufenozide, fenarimol, benalaxyl, penconazole, and tetradifon) that are currently being used in the Canary Islands (Spain). The optimized MEKC buffer, consisting of 100 mM sodium tetraborate and 30 mM SDS at pH 8.5 with 6% v/v 1-propanol, provided baseline resolution of the 12 pesticides in less than 20 min. The developed method was applied to the analysis of mineral, stagnant, and tap water samples. The proposed SPE-REPSM-MEKC-UV method showed high extraction efficiencies with detection limits (LODs) at the low ng/L level providing LOD values down to 64 ng/L for these real samples.

Combining solid-phase microextraction and on-line preconcentration-capillary electrophoresis for sensitive analysis of pesticides in foods.

The combined use of solid-phase microextraction (SPME) and different on-line preconcentration strategies for ultrasensitive capillary electrophoresis-ultraviolet (CE-UV) analysis of five pesticides in a single run is investigated. Normal stacking mode (NSM), field-enhanced sample injection (FESI), and stacking with matrix removal (SWMR) are explored to increase the sensitivity of the CE-UV analysis of a selected group of pesticides (cyprodinil, cyromazine, pyrifenox, pirimicarb, and pyrimethanil). It could be observed that reverse polarity-stacking with matrix removal (RP-SWMR) provided the best results in terms of sensitivity (enhancement was up to 272-fold compared with normal injection). The separation buffer consisted of 0.4 mM cetyltrimethylammonium chloride (CTAC), 0.4 M acetic acid at pH 4 containing 5% v / v 2-propanol. This approach was then combined with SPME to determine the pesticides in water, apple, and orange juice. The combination of both preconcentration procedures allowed the determination of these pesticides at concentrations down to 2.5 microg / L in water and 3.1 microg / L in juices (i.e., levels well below the maximum residue limits allowed for these compounds). To our knowledge, this is the first report showing the great possibilities of the combined use of SPME, on-line sample preconcentration, and CE for pesticide analysis.

Optimization of a solid-phase microextraction procedure for the determination of herbicides by micellar electrokinetic chromatography.

The use of a different optimization procedure that involves Experimental Design (ED) and Artificial Neural Networks (ANN) for the off-line coupling solid-phase microextraction-micellar electokinetic chomatography (SPME-MEKC) is presented. This combination of ED and ANN, mathematical tools not previously used in SPME-MEKC optimization, allowed us to obtain good extraction efficiencies in the SPME procedure for the determination of a group of eleven triazine herbicides in groundwater samples. Both extraction and desorption steps were carried out by solution stirring at 900 rpm. Optimal conditions for the off-line SPME procedure were: extraction with a poly(dimethylsiloxane)/divinylbenzene SPME fiber for 120 min, 10% (w/v) NaCl, desorption time 40 min, and 70% (v/v) of methanol/buffer as desorption mixture. Detection limits lay between 0.80 microg L(-1) and 4.89 microg L(-1). Finally, the optimized method was applied to the determination of these compounds in spiked and non-spiked groundwater samples using a previously optimized MEKC separation.

Highly sensitive analysis of multiple pesticides in foods combining solid-phase microextraction, capillary electrophoresis-mass spectrometry, and chemometrics.

A highly sensitive procedure to detect multiple pesticides at trace levels in foods is presented. Initially a comparative study between capillary electrophoresis (CE)-UV and CE-mass spectrometry (MS) is carried out analyzing five pesticides not studied up to now (pyrimethanil, pyrifenox, cyprodinil, cyromazine, and pirimicarb). The comparison between CE-UV and CE-MS is established in terms of separation efficiency, speed of analysis, reproducibility, and sensitivity. A good separation of these compounds is achieved by both techniques using a volatile aqueous buffer containing 0.3 M ammonium acetate/acetic acid at pH 4. Time analysis reproducibility is studied for the same day (n = 5) and three different days (n = 15), showing no significant differences between CE-UV and CE-MS. The study on peak areas reproducibility shows a slightly worse reproducibility for CE-MS compared with CE-UV. The best limit of detection (LOD) that can be achieved for these pesticides using CE-UV was 0.6 microg/mL. CE-MS provides LODs one order of magnitude better than CE-UV. Chemometrics are used to optimize the multiple parameters that play a role in solid-phase microextraction (SPME) and CE-MS analysis (e.g., extraction and desorption times, nebulizer pressure, dry gas flow, dry gas temperature, percentage of organic solvent and acid in the sheath liquid, etc.). The combined use of chemometrics and SPME-CE-MS clearly improves the LODs that can be achieved allowing the detection of pesticides at concentrations down to 15 ng/mL. The usefulness of this approach is demonstrated detecting multiple pesticides in different food samples as grapes and orange juice in a single run. The concentrations detected are below the maximum residue limits (MRLs) permitted for these pesticides in foods corroborating the value of our approach. This work demonstrates, to our knowledge for the first time, the good possibilities of the combined use of SPME-CE-MS and chemometrics.

Interaction between hemoglobin and glutathione in the regulation of blood flow in normal and septic pigs.

BACKGROUND: Hemoglobin (Hb) induces vasoconstriction by heme group binding nitric oxide in an irreversible fashion. Recent in vitro studies indicate that the thiol groups in Hb reversibly bind nitric oxide and participate in trans-nitrosylation reactions with other thiols. Sepsis is a pathophysiologic state characterized by vasodilation mediated, at least in part, by an excessive release of nitric oxide. The role of nitrosothiols (RSNOs) in these changes is unknown. OBJECTIVES: We tested the following in a porcine model of sepsis: (i) whether glutathione (GSH) reverses the hemodynamic effects of Hb; (ii) whether GSH induces an increase in blood flow in sepsis; (iii) whether RSNO plasma concentration increases in sepsis and is related to hypotension. DESIGN: Nonrandomized animal controlled study. SETTING: Animal research facility in a university hospital. SUBJECTS: Anesthetized pigs were monitored with a pulmonary artery catheter and ultrasonic blood flow probes in the mesenteric artery and the portal vein for measurement of systemic, mesenteric, and portal blood flows (Q(TOT), Q(MES), and Q(POR), respectively). Four groups of pigs were studied: nonseptic, septic, nonseptic treated with Hb (stroma-free purified porcine hemoglobin), and septic treated with Hb (n = 6 in each group). INTERVENTIONS: Sepsis was induced at 0 min by the administration of live Escherichia coli. Hb (400 mg/kg/hr) was administered at 240 mins, followed by glutathione (1 g iv). MEASUREMENTS AND MAIN RESULTS: Hb induced a pressor response and a decrease in Q(TOT), Q(MES), and Q(POR). Glutathione reversed the effects of Hb on Q(MES) and Q(POR). In septic pigs not treated with Hb, GSH induced an increase in Q(POR). RSNO plasma concentration increased after the induction of sepsis and correlated significantly with blood pressure. CONCLUSIONS: These results indicate the reversibility of the effects of Hb by GSH, probably by interactions between nitric oxide and the reduced sulfhydryl groups in Hb, and suggest a role of RSNOs in the cardiovascular changes of sepsis.