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Microquasars are laboratories for the study of jets of relativistic particles produced by accretion onto a spinning black hole. Microquasars are near enough to allow detailed imaging of spatial features across the multiwavelength spectrum. The recent extension measurement of the spatial morphology of a microquasar, SS 433, to TeV gamma rays1localizes the acceleration of electrons at shocks in the jet far from the black hole2. V4641 Sagittarii (V4641 Sgr) is a similar binary system with a black hole and B-type main-sequence companion star and has an orbit period of 2.8 days (refs. 3,4). It stands out for its super-Eddington accretion5and for its radio jet, which is one of the fastest superluminal jets in the Milky Way. Previous observations of V4641 Sgr did not report gamma-ray emission6. Here we report TeV gamma-ray emission from V4641 Sgr that reveals particle acceleration at similar distances from the black hole as SS 433. Furthermore, the gamma-ray spectrum of V4641 Sgr is among the hardest TeV spectra observed from any known gamma-ray source and is detected above 200 TeV. Gamma rays are produced by particles, either electrons or protons, of higher energies. Because energetic electrons lose energy more quickly the higher their energy, such a spectrum either very strongly constrains the electron-production mechanism or points to the acceleration of high-energy protons. This suggests that large-scale jets from microquasars could be more common than previously expected and that they could be a notable source of galactic cosmic rays7–9.

Chlorhexidine skin antisepsis is frequently recommended for most surgical procedures; however, it is unclear if these recommendations should apply to surgery involving traumatic contaminated wounds where povidone-iodine has previously been preferred. We aimed to compare the effect of aqueous 10% povidone-iodine versus aqueous 4% chlorhexidine gluconate on the risk of surgical site infection in patients who required surgery for an open fracture.

Abstract:Today, many women suffer negative thoughts about their body appearance and want to lose weight. Mass media are a major influence on women’s body dissatisfaction; thus, the present study content analyzes female models’ body sizes in magazines to better understand what today’s women are exposed to and compares results to past studies to see if new bans on ultrathin models and the body-positivity movement have impacted body size. The results showed that media models have generally increased in body size, albeit in different ways, depending on magazine genre, individual magazine titles, models’ race, and image type.

SS 433 is a binary system containing a supergiant star that is overflowing its Roche lobe with matter accreting onto a compact object (either a black hole or neutron star)1–3. Two jets of ionized matter with a bulk velocity of approximately 0.26c(where cis the speed of light in vacuum) extend from the binary, perpendicular to the line of sight, and terminate inside W50, a supernova remnant that is being distorted by the jets2,4–8. SS 433 differs from other microquasars (small-scale versions of quasars that are present within our own Galaxy) in that the accretion is believed to be super-Eddington9–11, and the luminosity of the system is about 1040ergs per second2,9,12,13. The lobes of W50 in which the jets terminate, about 40 parsecs from the central source, are expected to accelerate charged particles, and indeed radio and X-ray emission consistent with electron synchrotron emission in a magnetic field have been observed14–16. At higher energies (greater than 100 gigaelectronvolts), the particle fluxes of ?-rays from X-ray hotspots around SS 433 have been reported as flux upper limits6,17–20. In this energy regime, it has been unclear whether the emission is dominated by electrons that are interacting with photons from the cosmic microwave background through inverse-Compton scattering or by protons that are interacting with the ambient gas. Here we report teraelectronvolt ?-ray observations of the SS 433/W50 system that spatially resolve the lobes. The teraelectronvolt emission is localized to structures in the lobes, far from the centre of the system where the jets are formed. We have measured photon energies of at least 25 teraelectronvolts, and these are certainly not Doppler-boosted, because of the viewing geometry. We conclude that the emission—from radio to teraelectronvolt energies—is consistent with a single population of electrons with energies extending to at least hundreds of teraelectronvolts in a magnetic field of about 16 microgauss.

ABSTRACTLittle is known about the procedural, risk, and benefit information on cosmetic surgery websites despite cosmetic surgery's potential health risks and the facts that websites influence patient decisions to have surgery yet are advertising tools for the industry, and the majority of patients get their information from the Internet. This study content analyzed website information for the top five surgical procedures, finding few differences among procedure types and the procedure, risk, benefit, and candidate screening information. However, when differences were found, the least risky procedures provided more procedural information than the riskiest procedures. Approximately half of the sites mentioned no benefits and candidate screening, while half had a moderate to high amount of risk information. Thus, websites did emphasize risks over benefits. Moreover, few differences were found based on the site sponsor and risk, benefit, and procedure information. When differences were found, most showed commercial sites providing the greatest amount of information. Finally, this study concludes by discussing and presenting ethical guidelines for future cosmetic surgery advertising.

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The objectives of this study were to evaluate degradation of ergovaline in a tall fescue [Lolium arundinaceum(Schreb.) Darbysh.] seed extract by rumen microbiota ex vivo and to identify specific bacteria capable of ergovaline degradation in vitro. Rumen cell suspensions were prepared by harvesting rumen fluid from fistulated wether goats (n= 3), straining, and differential centrifugation. Suspensions were dispensed into anaerobic tubes with added Trypticase with or without extract (∼10 μg kg-1ergovaline). Suspensions were incubated for 48 h at 39°C. Samples were collected at 0, 24, and 48 h for ergovaline analysis and enumeration of hyper-ammonia producing (HAB) and tryptophan-utilizing bacteria. Ergovaline values were analyzed by repeated measures using the mixed procedure of SAS. Enumeration data were log transformed for statistical analysis. When suspensions were incubated with extract, 11 to 15% of ergovaline disappearance was observed over 48 h (P= 0.02). After 24 h, suspensions with added extract had 10-fold less HAB than controls (P= 0.04), but treatments were similar by 48 h (P= 1.00). However, after 24 h and 48 h, suspensions with extract had 10-fold more tryptophan-utilizing bacteria (P< 0.01) that were later isolated and identified by their 16S RNA gene sequence as Clostridium sporogenes. The isolates and other known rumen pure cultures (Streptococcus bovisJB1, Megasphaera elsdeniiB159, Selenemonas ruminatiumHD4, Prevotella bryantiiB14, Ruminococcus flavefaciens, Clostridium aminophilumF, Clostridium sporogenesMD1, Clostridium sticklandiiSR) were evaluated for the ability to degrade ergovaline in vitro. Pure culture cell suspensions were incubated as described above and samples were taken at 0 and 48 h for ergovaline analysis. Data were analyzed using the ANOVA procedure of SAS. All HAB, including the isolates, tested degraded ergovaline (54 to 75%; P< 0.05). Prevotella bryantiiB14 was also able to degrade ergovaline but to a lesser capacity (12%; P< 0.05), but all other bacteria tested did not degrade ergovaline. The results of this study indicate which rumen bacteria may play an important role in ergovaline degradation and that microbiological strategies for controlling their activity could have ramifications for fescue toxicosis and other forms of ergotism in ruminants.

AbstractThe optimum parameters for the generation of synchrotron radiation in ultraintense laser pulse interactions with planar foils are investigated with the application of Bayesian optimization, via Gaussian process regression, to 2D particle-in-cell simulations. Individual properties of the synchrotron emission, such as the yield, are maximized, and simultaneous mitigation of bremsstrahlung emission is achieved with multi-variate objective functions. The angle-of-incidence of the laser pulse onto the target is shown to strongly influence the synchrotron yield and angular profile, with oblique incidence producing the optimal results. This is further explored in 3D simulations, in which additional control of the spatial profile of synchrotron emission is demonstrated by varying the polarization of the laser light. The results demonstrate the utility of applying a machine learning-based optimization approach and provide new insights into the physics of radiation generation in laser–foil interactions, which will inform the design of experiments in the quantum electrodynamics (QED)-plasma regime.

Objective:: To evaluate asphyxial patterns in term encephalopathic newborns caused by chorioamnionitis or intrapartum blood loss that resulted in cerebral palsy and allegations of obstetrical professional liability. Study Design:: As an expert witness, JKM identified term newborns with profound neurologic impairment: 18 born in the presence of chorioamnionitis and 14 with significant anemia. Result:: In both study groups, profound depression with low 10-min Apgars was associated with early-onset seizures (88%), multiorgan failure (94%) and a partial prolonged injury to the cortex and subcortical white matter (94%). A cord arterial pH>7.00 was noted in 68% and deep gray matter injury involving the basal ganglia and thalamus occurred in only 19% of the newborns studied. Conclusion:: The cord arterial pH and pCO2 values, early-onset seizures and paucity of isolated deep gray matter injury support that significant injury occurred postnatally despite appropriate resuscitation. This unique pattern may refute allegations of obstetrical mismanagement in the intrapartum period.

At the initiation of the COVID-19 pandemic, restrictions forced researchers to decide whether to continue their ongoing clinical trials. The PREPARE (Pragmatic Randomized Trial Evaluating Pre-Operative Alcohol Skin Solutions in Fractured Extremities) trial is a pragmatic cluster-randomized crossover trial in patients with open and closed fractures. PREPARE was enrolling over 200 participants per month at the initiation of the pandemic. We aim to describe how the COVID-19 research restrictions affected participant enrollment.

Pragmatic trials in comparative effectiveness research assess the effects of different treatment, therapeutic, or healthcare options in clinical practice. They are characterized by broad eligibility criteria and large sample sizes, which can lead to an unmanageable number of participants, increasing the risk of bias and affecting the integrity of the trial. We describe the development of a sampling strategy tool and its use in the PREPARE trial to circumvent the challenge of unmanageable work flow.

We present the Young Exoplanet Transit Initiative (YETI), in which we use several 0.2 to 2.6‐m telescopes around the world to monitor continuously young (≤100 Myr), nearby (≤1 kpc) stellar clusters mainly to detect young transiting planets (and to study other variability phenomena on time‐scales from minutes to years). The telescope network enables us to observe the targets continuously for several days in order not to miss any transit. The runs are typically one to two weeks long, about three runs per year per cluster in two or three subsequent years for about ten clusters. There are thousands of stars detectable in each field with several hundred known cluster members, e.g. in the first cluster observed, Tr‐37, a typical cluster for the YETI survey, there are at least 469 known young stars detected in YETI data down to R = 16.5 mag with sufficient precision of 50 millimag rms (5 mmag rms down to R = 14.5 mag) to detect transits, so that we can expect at least about one young transiting object in this cluster. If we observe ∼10 similar clusters, we can expect to detect ∼10 young transiting planets with radius determinations. The precision given above is for a typical telescope of the YETI network, namely the 60/90‐cm Jena telescope (similar brightness limit, namely within ±1 mag, for the others) so that planetary transits can be detected. For targets with a periodic transit‐like light curve, we obtain spectroscopy to ensure that the star is young and that the transiting object can be sub‐stellar; then, we obtain Adaptive Optics infrared images and spectra, to exclude other bright eclipsing stars in the (larger) optical PSF; we carry out other observations as needed to rule out other false positive scenarios; finally, we also perform spectroscopy to determine the mass of the transiting companion. For planets with mass and radius determinations, we can calculate the mean density and probe the internal structure. We aim to constrain planet formation models and their time‐scales by discovering planets younger than ∼100 Myr and determining not only their orbital parameters, but also measuring their true masses and radii, which is possible so far only by the transit method. Here, we present an overview and first results (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Darbepoetin alfa (darbEpo) is an erythropoietic glycoprotein that activates the erythropoietin receptor. The aim of our study was to determine whether darbEpo is neuroprotective in a cortical impact injury (CII) model and to determine the characteristics of dose response and time window. To better understand the vascular mechanism of darbEpo neuroprotection, the reactivity of cerebral blood flow (CBF) to l-arginine administration was also studied. Rats were given saline or darbEpo from 2.5 to 50 μg/kg at 5 min after CII or a dose of 25 μg/kg darbEpo at times ranging from 5 min to 24 h after CII. Histological assessment was determined 2 weeks after a severe CII. Other rats were given either darbEpo (25 μg/kg) or saline daily for 3 days before injury. Five minutes after severe CII, they were given either l-arginine or d-arginine. Hemodynamic variables were monitored for 2 h after injury. In the dose-response study, darbEpo in doses of 25 and 50 μg/kg significantly reduced contusion volume from 39.1 ± 6.7 to 8.1 ± 3.1 and 11.2 ± 6.0 mm(3), respectively. In the time window study, darbEpo reduced contusion volume when given in a dose of 25 μg/kg at 5 min to 6 h after the impact injury. In animals pretreated with darbEpo, the CBF response to l-arginine was significantly greater than in the animals pretreated with saline. These data demonstrate that darbEpo has neuroprotective effects in traumatic brain injury in a dose- and time-dependent manner and that vascular effects of darbEpo may have a role in neuroprotection.

This review highlights recent advances in cerebral microdialysis for investigational and clinical neurochemical monitoring in patients with critical neurological conditions.

Numerous studies have explored the relationship between female beauty and positive effects for the woman, product, or ad; however, none has explored women's emotional responses to different beauty types. This study investigated college women's emotional responses to Solomon, Ashmore, and Longo's six beauty types. The survey results revealed that the original six beauty types were not supported. Instead, they combined into two independent dimensions: Sexual/Sensual (SS) and Classic Beauty/Cute/Girl-Next-Door (CCG). After testing emotional reactions to High CCG/Low SS, High SS/Low CCG, and Equal CCG/SS models, models with higher degrees of CCG produced significantly greater pleasure, arousal, and dominance.

This study was designed to determine the effect of erythropoietin (Epo) on cerebral blood flow (CBF), nitric oxide (NO) concentration, and neurological outcome after traumatic brain injury. In one experiment, the hemodynamic effects of Epo were determined after controlled cortical impact injury (CCII) by measuring mean arterial pressure, intracranial pressure, CBF using laser Doppler flowmetry, and brain tissue NO concentrations using an NO electrode. In total, 41 rats were given either Epo (5000 U/kg) or saline s.c. 3 days before injury. In animals pretreated with saline, l-arginine but not d-arginine administration resulted in a significant increase in tissue NO concentrations and an improvement in CBF at the impact site. Likewise, in animals pretreated with Epo, l-arginine but not d-arginine given postinjury increased brain tissue NO concentrations and increased CBF. In another experiment, 74 rats underwent CCII (3-mm deformation, velocity 5 m/s), and they were given saline or Epo 5000 U/kg s.c. at 5 min, 1 h, 3 h, 6 h, 9 h, or 12 h postinjury. The contusion volume and cell counts of viable neurons in the CA1 and CA3 regions of the hippocampus were assessed at 2 weeks postinjury. The contusion volume was significantly reduced at 5 min, 1 h, 3 h, and 6 h postinjury Epo administration. The neuron density in the CA1 and CA3 region of the hippocampus was increased at 1, 3, and 6 h after injury. These data demonstrate the neuroprotective effects of Epo in traumatic injury, and the effects are optimal when Epo is given with in 6 h of injury.

Background: The introduction of the RP6 (InTouch Health, Santa Barbara, CA, USA) remote-presence “robot” appears to offer a useful telemedicine device. The authors describe the deployment and early experience with the RP6 in a community hospital and provided a live demonstration of the system on April 16, 2005 during the Emerging Technologies Session of the 2005 SAGES Meeting in Fort Lauderdale, Florida. Methods: The RP6 is a 5-ft 4-in. tall, 215-pound robot that can be remotely controlled from an appropriately configured computer located anywhere on the Internet (i.e., on this planet). The system is composed of a control station (a computer at the central station), a mechanical robot, a wireless network (at the remote facility: the hospital), and a high-speed Internet connection at both the remote (hospital) and central locations. The robot itself houses a rechargeable power supply. Its hardware and software allows communication over the Internet with the central station, interpretation of commands from the central station, and conversion of the commands into mechanical and nonmechanical actions at the remote location, which are communicated back to the central station over the Internet. The RP6 system allows the central party (e.g., physician) to control the movements of the robot itself, see and hear at the remote location (hospital), and be seen and heard at the remote location (hospital) while not physically there. Results: Deployment of the RP6 system at the hospital was accomplished in less than a day. The wireless network at the institution was already in place. The control station setup time ranged from 1 to 4 h and was dependent primarily on the quality of the Internet connection (bandwidth) at the remote locations. Patients who visited with the RP6 on their discharge day could be discharged more than 4 h earlier than with conventional visits, thereby freeing up hospital beds on a busy med–surg floor. Patient visits during “off hours” (nights and weekends) were three times more efficient than conventional visits during these times (20 min per visit vs 40-min round trip travel + 20-min visit). Patients and nursing personnel both expressed tremendous satisfaction with the remote-presence interaction. Conclusions: The authors’ early experience suggests a significant benefit to patients, hospitals, and physicians with the use of RP6. The implications for future development are enormous.

A reaction prediction program, ROBIA, has been developed. This interactive computer program predicts the products of organic reactions from the starting materials and the reaction conditions, on the basis of the selected transformations within its database. This mechanistic approach generates a large number of products, from which the most important are selected using filters and molecular modeling calculations. The procedure has been applied to the possible biosynthesis pathway of dolabriferol.

The Nuclear Regulatory Commission (NRC) announced the availability of three new documents concerning radioactive materials in sewage sludge and ash from publicly owned treatment works (POTW). One of the documents is a report presenting the results of a volunteer survey of sewage sludge and ash samples provided by 313 POTWs. The second document is a dose modeling document, using multiple exposure pathway modeling focused on a series of generic scenarios, to track possible exposure of POTW workers and members of the general public to radioactivity from the sewage sludge or ash. The third document is a guidance report providing recommendations on the management of radioactivity in sewage sludge and ash for POTW owners and operators. This paper explains how radioactive materials enter POTWs, provides criteria for evaluating levels of radioactive material in sludge and ash, and gives a summary of the results of the survey and dose modeling efforts.

Saturated acyclic alkanes may show a high degree of strain if they have many branches close to each other. We report calculations which indicate how strained a molecule may become before it falls apart rapidly at room temperature and so allow us to identify the simplest alkane which cannot be made.

Through focus group interviews, this study examined how college women negotiate exposure to media images of disproportionately large-breasted women. The results showed that media images directly and indirectly influence women's breast satisfaction. Personal experiences; self-confidence; and interactions with men, family, and friends influenced their views of ideal breast size.

The purpose of this study was to examine the patterns of change in microdialysate concentrations of glucose, lactate, pyruvate, and glutamate in the brain during periods of hypoxia/ischemia identified by monitoring brain tissue pO2 (PbtO2). Of particular interest was a better understanding of what additional information could be obtained by the microdialysis parameters that was not available from the PbtO2. Fifty-seven patients admitted with severe traumatic brain injury who had placement of both a brain tissue pO2 (PbtO2) and microdialysis probe were studied. The microdialysis probe was perfused with Ringer's solution at 0.3 μL/min and dialysate was collected at 1-h intervals. The concentration of glucose, pyruvate, lactate, and glutamate were measured in each dialysate sample. Changes in the microdialysis parameters were examined during episodes where the PbtO2 decreased to below 10 mm Hg. Ten episodes of tissue hypoxia/ischemia identified by a decrease in PbtO2 below 10 mm Hg were observed during the period of monitoring. The concentration of the dialysate glucose closely followed the PbtO2. The dialysate pyruvate concentration was more variable and in some patients transiently increased as the PbtO2 dropped below 10 mm Hg. The dialysate concentration of lactate was significantly increased as the PbtO2 decreased to less than 10 mm Hg. Dialysate glutamate was significantly elevated only when PbtO2 decreased to very low levels. Although changes in the PbtO2 provided the earliest sign of hypoxia/ischemia, the microdialysis assays provided additional information about the consequences that the reduced tissue pO2 has on brain metabolism, which may be helpful in managing these critically ill patients.

We report the first theoretical studies on the asymmetric sulfonium ylide epoxidation reaction using a chiral sulfide that successfully reproduces the experimentally determined high enantiomeric excess. Calculations at the DFT level suggest that the transition states for the addition of the sulfonium ylide to benzaldehyde have energies which account for the observed enantioselectivity.

Presents letters to the editor referencing articles and topics discussed in previous issues of "What Is Enlightenment." "Morality Bites," which focused on ethics in a postmodern world; "Shifting Moral Ground: The Dilemma of Ethics in an Out-of-Control World," which dealt with evolutionary morality; "America as Empire," which examined attitudes prevalent in the U.S.

Dendritic cells are potent antigen-presenting cells that initiate and amplify immune responses. To determine whether dendritic cells participate in inflammatory reactions in amyotrophic lateral sclerosis (ALS), we examined mRNA expression of dendritic cell surface markers in individual sporadic ALS (sALS), familial ALS (fALS), and nonneurological disease control (NNDC) spinal cord tissues using semiquantitative and real-time reverse transcription polymerase chain reaction (RT-PCR). Immature (DEC205, CD1a) and activated/mature (CD83, CD40) dendritic cell transcripts were significantly elevated in ALS tissues. The presence of immature and activated/mature dendritic cells (CD1a⁺ and CD83⁺) was confirmed immunohistochemically in ALS ventral horn and corticospinal tracts. Monocytic/macrophage/microglial transcripts (CD14, CD18, SR-A, CD68) were increased in ALS spinal cord, and activated CD68⁺ cells were demonstrated in close proximity to motor neurons. mRNA expressions of the chemokine MCP-1, which attracts monocytes and myeloid dendritic cells, and of the cytokine macrophage-colony stimulating factor (M-CSF) were increased in ALS tissues. The MCP-1 protein was expressed in glia in ALS but not in control tissues and was increased in the CSF of ALS patients. Those patients who progressed most rapidly expressed significantly more dendritic transcripts than patients who progressed more slowly. These results support the involvement of immune/inflammatory responses in amplifying motor neuron degeneration in ALS.

Dendritic cells are potent antigen‐presenting cells that initiate and amplify immune responses. To determine whether dendritic cells participate in inflammatory reactions in amyotrophic lateral sclerosis (ALS), we examined mRNA expression of dendritic cell surface markers in individual sporadic ALS (sALS), familial ALS (fALS), and nonneurological disease control (NNDC) spinal cord tissues using semiquantitative and real‐time reverse transcription polymerase chain reaction (RT‐PCR). Immature (DEC205, CD1a) and activated/mature (CD83, CD40) dendritic cell transcripts were significantly elevated in ALS tissues. The presence of immature and activated/mature dendritic cells (CD1a+and CD83+) was confirmed immunohistochemically in ALS ventral horn and corticospinal tracts. Monocytic/macrophage/microglial transcripts (CD14, CD18, SR‐A, CD68) were increased in ALS spinal cord, and activated CD68+cells were demonstrated in close proximity to motor neurons. mRNA expressions of the chemokine MCP‐1, which attracts monocytes and myeloid dendritic cells, and of the cytokine macrophage‐colony stimulating factor (M‐CSF) were increased in ALS tissues. The MCP‐1 protein was expressed in glia in ALS but not in control tissues and was increased in the CSF of ALS patients. Those patients who progressed most rapidly expressed significantly more dendritic transcripts than patients who progressed more slowly. These results support the involvement of immune/inflammatory responses in amplifying motor neuron degeneration in ALS.

Traumatic brain injury causes a reduction in cerebral blood flow, which may cause additional damage to the brain. The purpose of this study was to examine the role of nitric oxide produced by endothelial nitric oxide synthase (eNOS) in these vascular effects of trauma. To accomplish this, cerebral hemodynamics were monitored in mice deficient in eNOS and wild-type control mice that underwent lateral controlled cortical impact injury followed by administration of either L-arginine, 300 mg/kg, or saline at 5 min after the impact injury. The eNOS deficient mice had a greater reduction in laser Doppler flow (LDF) in the contused brain tissue at the impact site after injury, despite maintaining a higher blood pressure. L-Arginine administration increased LDF post-injury only in the wild-type mice. L-Arginine administration also resulted in a reduction in contusion volume, from 2.4 ± 1.5 to 1.1 ± 1.2 mm3 in wild-type mice. Contusion volume in the eNOS deficient mice was not significantly altered by L-arginine administration. These differences in cerebral hemodynamics between the eNOS-deficient and the wild-type mice suggest an important role for nitric oxide produced by eNOS in the preservation of cerebral blood flow in contused brain following traumatic injury, and in the improvement in cerebral blood flow with L-arginine administration.

Redox and/or electrophilic metabolites formed during estrogen metabolism may play a role in estrogen carcinogenesis. 4-Hydroxyequilenin (4-OHEN) is the major phase I catechol metabolite of the equine estrogens equilenin and equilin, which are components of the most widely prescribed estrogen replacement formulation, Premarin. Previously, we have found that 4-OHEN rapidly autoxidized to an o-quinone in vitro and caused toxic effects such as the inactivation of human detoxification enzymes. 4-OHEN has also been shown to be a substrate for catechol-O-methyltransferase (COMT) in human breast cancer cells. In the present study, we demonstrated that 4-OHEN was not only a substrate of recombinant human soluble COMT in vitro with a Km of 2.4 μM and kcat of 6.0 min^-1 but it also inhibited its own methylation by COMT at higher concentrations in the presence of the reducing agent dithiothreitol. In addition, 4-OHEN was found to be an irreversible inhibitor of COMT-catalyzed methylation of the endogenous catechol estrogen 4-hydroxyestradiol with a Ki of 26.0 μM and a k2 of 1.62 × 10^-2 s^-1. 4-OHEN in vitro not only caused the formation of intermolecular disulfide bonds as demonstrated by gel electrophoresis, but electrospray ionization mass spectrometry and matrix-assisted laser desorption ionization time-of-flight mass spectrometry also showed that 4-OHEN alkylated multiple residues of COMT. Peptide mapping experiments further indicated that Cys33 in recombinant human soluble COMT was the residue most likely modified by 4-OHEN in vitro. These data suggest that inhibition of COMT methylation by 4-OHEN might reduce endogenous catechol estrogen clearance in vivo and further enhance toxicity.

In an effort to localize the site at which increased resistance occurs after brain trauma, pial arteriole diameter and pressure were assessed after mild controlled cortical impact (CCI) injury in rats using an open cranial window technique. The authors tested the hypothesis that an increase in resistance accompanied by vasoconstriction occurs at the level of the pial arterioles within the injured cortex of the brain. At 1 hour after mild CCI injury, ipsilateral cerebral blood flow was significantly reduced by 42% compared with sham injury (n = 4; P< 0.05). Pial arteriole diameter and pressure remained unchanged. Resistance in the larger arteries (proximal resistance), however, was significantly greater after CCI injury (1.87 ± 0.26 mm Hg/[mL · 100 g · min]) compared with sham injury (0.91 ± 0.21 mm Hg/[mL · 100 g ·min]; P< 0.0001). Resistance in small vessels, arterioles, and venules (distal resistance) was also significantly greater after CCI injury (1.13 ± 0.05 mm Hg/[mL · 100 g · min]) compared with sham injury (0.74 ± 0.13 mm Hg/[mL · 100 g · min]; P= 0.0001). The authors conclude that, at 1 hour after mild CCI injury, changes in vascular resistance comprise a 53% increase in the resistance distal to the area of injury and, surprisingly, a 105% increase in resistance in the arteries proximal to the injury site.

This paper examined how Latina and Anglo women negotiate excessively thin, female images in the media. Twenty-four Latina and Anglo women participated in focus groups in which they were asked questions about beliefs, attitudes, and behaviors regarding the mediated ideal body in magazines. Glaser and Strauss's (1967) constant comparison method showed that the women's beliefs and attitudes came from primarily negotiated readings of the mediated ideal, but they had more hegemonic readings with regard to behavior. Furthermore, Latina women's exposure to Hispanic culture, with its alternative feminine ideal, as well as to the dominant Anglo culture, enabled them to resist the mediated ideal more than could Anglo women.

We have studied the influence of electric field on fluorescence in particles of photoconductive TiOPc (I), TiOPc (IV), HOGaPc, and x-H2Pc dispersed in a polymer matrix. Electric field induced quenching of both the integrated and time-resolved fluorescence were measured. Time-resolved fluorescence decays were analyzed by fitting the data to a sum of two exponentials, representing the fast and slow fluorescence components. For HOGaPc, TiOPc(I), and TiOPc (IV), the fast fluorescence component exhibits both amplitude and lifetime quenching. These results indicate that carrier generation in HOGaPc, TiOPc(I), and TiOPc (IV) originates from both relaxed and nonrelaxed intrinsic excited singlet states, while the trapped excitons do not lead to significant carrier production. In contrast, for x-H2Pc, significant amplitude quenching of the fast component is observed only at high field, and the trapped excitons are an important source of photogenerated carriers. This indicates that x-H2Pc possesses at least some bulk-sensitized photocarrier generation. All of the phthalocyanines studied exhibited a quadratic dependence of integrated fluorescence quenching on electric field, indicating the existence of a neutral carrier precursor state.

This analysis of television advertisements aired during NBC's telecast of the 2000 NBC Summer Olympics examined advertisers' use of Jungian-based concepts of heroism and gendered concepts of heroism. Using traditional archetypes of heroes—the Innocent, Orphan, Martyr, Wanderer, Warrior, and Magician—the study analyzed commercials featuring Olympic athletes. Findings were that male and female athletes were equally portrayed as Warriors. However, male athletes were more likely to be portrayed as preparing for and doing battle successfully while female athletes were more likely to be celebrated for their athletic skills and achievements.

The rejection of xenografts is characterized by infiltration of monocytes and natural killer (NK) cells into the graft, suggesting an important role for the innate immune system in xenorecognition. In this study, purified human NK or T cells were cocultured with porcine endothelial cells, and cytokines were analyzed by ELISA and intracellular FACS. We demonstrated a vigorous human anti-porcine xenoresponse that was associated with a strong T-cell proliferation against porcine endothelial cells. Limiting dilution cloning and T-cell receptor (TCR) Vβ gene usage revealed a low number of xenoreactive T-cell precursors. We demonstrated that xenogeneic porcine but not allogeneic human endothelial cells induced the early production of interferon (IFN)-γ by human NK cells but not by CD3⁺ T cells. Porcine xenoantigen-induced IFN-γ production was only partially dependent on IL-12. Blocking IL-12 with neutralizing antibodies or by depletion of human macrophages partially decreased IFN-γ production by CD56⁺ NK cells. Three-color flow cytometry revealed that IL-12 was produced through a species-specific activation of human macrophages by porcine endothelial cells. Our results indicate that the direct activation of NK cells and macrophages by porcine endothelial cells provides a unique pathway of xenorecognition that augments downstream specific T-cell immunity and represents a powerful effector mechanism in xenograft rejection.

Traumatic brain injury (TBI) induces vascular changes that may influence neurological outcome by causing the brain to be more susceptible to secondary ischemic insults. In rat models of TBI, L-arginine administration has been shown to restore cerebral blood flow and improve neurological outcome. The purpose of this study was to determine if hypoperfusion occurs in a mouse model of TBI and if L-arginine administration has the same beneficial effects after injury in the mouse. C57BL6 mice were anesthetized with isoflurane, intubated and mechanically ventilated, and underwent a 3-m/sec, 1.5-mm deformation cortical impact injury. Five minutes after injury, L-arginine, 300 mg/kg, or saline were administered. Arterial blood pressure, intracranial pressure, and laser Doppler flow at the impact site were monitored for 3 h after the injury. The cerebral hemodynamic effects of the TBI induced by cortical impact injury were similar to that previously observed in rats. Intracranial hypertension, with ICP peaking at 46 ± 2 mm Hg, and systemic hypotension both contributed to a reduction in CPP. In addition, LDF decreased significantly at the impact site. L-Arginine administration restored LDF to near baseline levels without increasing ICP. These studies demonstrate that cerebral hemodynamics can be measured in mouse models of TBI. The changes in cerebral hemodynamics are relatively simlar to those see in the rat model of cortical impact injury and suggest an important role for nitric oxide metabolism in the maintenance of cerebral blood flow following TBI.