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EGFR cell surface density, stability, internalization, and recycling can be measured by cell surface ELISA (cs-ELISA). Performing this experiment on ice impedes receptor internalization; thus the physiological cell surface receptor levels can be measured by cs-ELISA. Cell surface EGFR levels are detected by measuring Amplex Red fluorescence intensity. Although cell surface receptor levels can be measured by flow cytometry, cs-ELISA does not include cell dissociation steps that might affect cell surface receptor levels. For complete details on the use and execution of this protocol, please refer to Kazan et al. (2019).

The intensity of land use and management in permanent grasslands affects both biodiversity and important ecosystem services. Comprehensive knowledge about these intensities is a crucial factor for sustainable decision-making in landscape policy. For meadows, the management intensity can be described by proxies such as the mowing frequency, usually, a higher number of cuts indicate higher intensities. Dense time series of medium resolution (10–30 m) remote sensing data are suitable for the detection of mowing events. However, existing studies revealed a general lack of consensus about the most appropriate input data set for a consistent and reliable mowing detection. We systematically evaluated the synergistic use of acquisitions from Sentinel-1, Sentinel-2, and Landsat 8 to detect the occurrence, frequency, and date of mowing events as an indicator of grassland management intensity. Dense time series of NDVI (Sentinel-2 and Landsat 8), γ0 backscatter, backscatter cross-ratio, backscatter second-order texture metrics as well as 6-day interferometric coherence (Sentinel-1) were used as input features. All possible combinations of input features were tested to train a one-dimensional convolutional neural network, which enables enhanced exploitation of the temporal domain of the data. The evaluation was conducted on 64 meadows for an overall of 257 mowing events from 2017 to 2019 in Germany. Our results revealed that the combination of input features improves the detection performance. The highest overall accuracy was reached by a combination of NDVI, backscatter cross-ratio, and interferometric coherence with an F1-Score of 0.84. The mowing frequency was predicted with a mean absolute error of 0.38 events per year, while the date of the events was missed by 3.79 days on average. NDVI time series alone mostly underperformed in comparison to optical/SAR combinations but clearly outperformed input-sets that were solely based on SAR features. The proposed model performed well for meadows with low to medium management intensities but further testing is recommended for highly intensive managed parcels. The results clearly demonstrate the additional value of fusing time series of the three present Earth observation systems that deliver a freely available global coverage of the land surface at medium resolution.

It is well documented how chemosensory anxiety signals affect the perceiver's physiology, however, much less is known about effects on overt social behavior. The aim of the present study was to investigate the effects of chemosensory anxiety signals on trust and risk behavior in men and women. Axillary sweat samples were collected from 22 men during the experience of social anxiety, and during a sport control condition. In a series of five studies, the chemosensory stimuli were presented via an olfactometer to 214 participants acting as investors in a bargaining task either in interaction with a fictitious human co-player (trust condition) or with a computer program (risk condition). It could be shown that chemosensory anxiety signals reduce trust and risk behavior in women. In men, no effects were observed. Chemosensory anxiety is discussed to be transmitted contagiously, preferentially in women.

indexation en cours; Chemosensory anxiety signals effectively prime motor responses related to withdrawal behavior, such as the startle reflex, in adult humans. As the reproductive status strongly affects the response to social chemosignals, the current study examined whether chemosensory anxiety signals would augment the startle response in prepubertal children as it does in adults. Using cotton pads, axillary sweat was collected from 28 men while waiting for an important oral examination (anxiety condition), and during ergometer training (sport control condition). Using a constant-flow olfactometer, sweat samples and pure cotton samples (cotton control) were presented to 10 prepubertal girls aged 9-13years (M=11.25, SD=1.25) for 3000ms during inhalation. White noise bursts of 102dB(A) served as startle probes, and startle responses were recorded via electromyography of the orbicularis oculi muscle. The girls showed larger startle amplitudes to probes presented in the context of chemosensory anxiety signals as compared to a context of sport control sweat (p

SummaryEndosomal sorting complexes required for transport (ESCRT) drive cell surface receptor degradation resulting in attenuation of oncogenic signaling and pointing to a tumor suppressor function. Here, we show that loss of function of an ESCRT protein (HD-PTP encoded by the PTPN23 gene, located on the tumor suppressor gene cluster 3p21.3) drives tumorigenesis in vivo. Indeed, Ptpn23+/− loss predisposes mice to sporadic lung adenoma, B cell lymphoma, and promotes Myc-driven lymphoma onset, dissemination, and aggressiveness. Ptpn23+/−-derived tumors exhibit an unaltered remaining allele and maintain 50% of HD-PTP expression. Consistent with the role of HD-PTP in attenuation of integrin recycling, cell migration, and invasion, hemizygous Ptpn23+/− loss increases integrin β1-dependent B cell lymphoma survival and dissemination. Finally, we reveal frequent PTPN23 deletion and downregulation in human tumors that correlates with poor survival. Altogether, we establish HD-PTP/PTPN23 as a prominent haploinsufficient tumor suppressor gene preventing tumor progression through control of integrin trafficking.

The mirror-neuron-system (MNS) is involved in the perception of actions of humans and anthropomorphic robots. The current study investigates whether social interaction with a non-anthropomorphic robot is sufficient for a response of the MNS.Fifty-seven participants observed movements of a vacuum cleaning robot before and after it was handled by its owner. The robot was either humanized, being treated aggressively (n?=?30), or it was treated as an object (n?=?27). Electroencephalographic mu-activity is used as an index of MNS activity, because both are inversely correlated. Activity within the 8-13?Hz band was measured at central (mu-activity) and occipital (alpha-activity) electrodes. Further, the level of aggressiveness displayed by the robot's owner, and the participants' compassion were rated on visual analog scales.Mu-activity showed medium-sized correlations with rated aggressiveness and compassion: The more aggressive the action towards the robot was perceived (r?=?-.379, p?=?.004), and the more compassion was felt for the robot (r?=?-.339, p?=?.010), the less pronounced mu-activity was at electrode C3 in response to the robot's movement.Thus social interaction with a non-anthropomorphic robot might establish the robot as a social entity and is sufficient to activate the human MNS. Social interactions can establish non-anthropomorphic robots as social entities.Participants report compassion for an aggressively treated robot.Perceived aggressiveness towards a robot is negatively correlated with mu-activity.Participant's compassion for a robot is negatively correlated with mu-activity.Results support the theory that mind is attributed to victimized inanimate entities.

Optimal and efficient machining of high-temperature alloys is one of the main goals set by the manufacturing technology today, taking into account the unique properties of these materials, the required performance and the process parameters. One of the most important parameters investigated and presented in this paper is the optimal cooling and lubrication strategy. The application of various hybrid cooling strategies such as high-pressure cooling, cryogenic cooling and aerosol dry lubrication offers the potential to extend profitability and energy efficiency as well as high performance and improved surface integrity. The paper introduces fundamental functions, cooling systems and relationships that characterize the efficient utilization on standard machine tools. Based on fundamental investigations conducted using high-temperature alloys with poor machinability such as Titanium alloy Ti6Al4 V and Inconel 718, relevant influencing parameters are derived and optimization options are presented for the cooling strategies.

This review serves as a comprehensive discussion of chemosensory stimulation of the amygdala in healthy humans. Following an introduction of the neuroanatomy of chemosensory processing in primary and secondary olfactory structures, functional resonance magnetic imaging and positron imaging tomography studies are systematically categorized based on valence of stimuli, stimulus concentration, and paradigm-dependent amygdala activation. The amygdala shows patterns of lateralization due to stimulus valence. Main findings include pleasant odors being associated with bilateral or left amygdala activation, and unpleasant odors being associated with activation of the right amygdala, suggesting a crucial role of the right amygdala in evolutionary preservation. Potentially threatening social stimuli, however, might be processed apart from the olfactory system and tend to activate the left amygdala. Amygdala response to chemosensory stimuli correlated with simultaneous activation in the orbitofrontal cortex (OFC), piriform cortex (PC), and insula, suggesting a close-knit network of these areas during stimulus processing.

SummaryMembrane trafficking of integrins plays a pivotal role in cell proliferation and migration. How endocytosed integrins are targeted either for recycling or lysosomal delivery is not fully understood. Here, we show that fibronectin (FN) binding to α5β1 integrin triggers ubiquitination and internalization of the receptor complex. Acidification facilitates FN dissociation from integrin α5β1 in vitro and in early endosomes, promoting receptor complex deubiquitination by the USP9x and recycling to the cell surface. Depending on residual ligand occupancy of receptors, some α5β1 integrins remain ubiquitinated and are captured by ESCRT-0/I, containing histidine domain-containing protein tyrosine phosphatase (HD-PTP) and ubiquitin-associated protein 1 (UBAP1), and are directed for lysosomal proteolysis, limiting receptor downstream signaling and cell migration. Thus, HD-PTP or UBAP1 depletion confers a pro-invasive phenotype. Thus, pH-dependent FN-integrin dissociation and deubiquitination of the activated integrin α5β1 are required for receptor resensitization and cell migration, representing potential targets to modulate tumor invasiveness.

Tunable diode laser absorption spectroscopy combined with extractive sampling is used to quantify fuel and acetylene concentrations in a 32% ethylene-diluted, nitrogen diffusion flame. Additional major species concentrations are determined using quartz microprobe, direct-sampling mass spectrometry. Quantification of these mass spectra used a multilinear regression technique anchored by computed nitrogen concentration profiles in a simulation from Yale University. Because of the overlap in mass spectra features for ethylene, nitrogen, and carbon monoxide, both optical and mass spectrometric techniques are required to determine the suite of major species in this flame system. Good agreement is observed between these experimental measurements and numerical simulation of this flame system. Probe clogging in these sooting flames remains a challenge for all probe techniques and additional, non-intrusive optical diagnostics must be applied to characterize flame regions with substantial soot formation.

The aim of this paper was to create a model that predicts the different phenological BBCH macro-stages of barley in laboratory on the plot scale and to transfer the most suitable model to the landscape scale. To characterise the phenology, eight vitality and phenology-related vegetation parameters like leaf area index (LAI), Chl-SPAD content, C-content, N-content, C/N-content, canopy chlorophyll content (CCC), gravimetric water content (GWC) and vegetation height at the same time as all imaging hyperspectral measurements (AISA-EAGLE, 395–973 nm). These biochemical–biophysical vegetation parameters were investigated according to the different phenological macro-stages of barley. The predictive models were developed using four different types of vegetation indices (VI): (I) published VI’s, (II) reflectance VI’s as well as (III) VI (xy) formula combinations and (IV) a combination of all VI index types using the Library for Support Vector Machines (LibSVM) and tested with a recursive conditional correlation weighting selection algorithm (RCCW) to reduce the number of variables. To increase the performance of the model a 10-fold cross-validation was carried out for all statistical models. The GWC was found to be the most important variable for differentiating between the phenological macro-stages of barley. The most suitable model for predicting the phenological BBCH macro-stages was achieved by a model that combined all three kinds of VI’s: published VI’s, reflectance VI’s and formula combination VI’s with a classification accuracy of 84.80%. With the classification model for the reflectance VI’s Y = 746 nm and for the VI formula combinations Y = (527 + 612) nm and Y = (540 + 639) nm. The best predictive model was applied to the airborne AISA-EAGLE hyperspectral data to model the phenological macro-stages of barley at the landscape level. The classification error of the best predictive model of 12.80% as well as disturbance factors such as channels and areas with weeds or ruderal vegetation lead to misclassifications of BBCH macro-stages at the landscape level. By using One Sensor At Different Scales-Approach (OSADIS), sensor-specific differences in the model building and model transfer can be eliminated. The approach described in the paper for determining the phenology based on imaging hyperspectral RS data shows that in the process of plant phonological development a number of biochemical–biophysical vegetation traits in vegetation change, which can be thoroughly recorded with hyperspectral remote sensing technology. For this reason, hyperspectral RS constitutes an ideal, cost-effective and comparable approach, with whose help vegetation traits and changes can be quantified, which are key for ecological modelling.

Control of translation allows for the production of stoichiometric levels of each protein in the cell. Attaining such a level of fine-tuned regulation of protein production requires the coordinated temporal and spatial control of numerous cellular signalling cascades impinging on the various components of the translational machinery. Foremost among these is the mTOR signalling pathway. The mTOR pathway regulates both the initiation and elongation steps of protein synthesis through the phosphorylation of numerous translation factors, while simultaneously ensuring adequate folding of nascent polypeptides through co-translational degradation of misfolded proteins. Perhaps most remarkably, mTOR is also a key regulator of the synthesis of ribosomal proteins and translation factors themselves. Two seminal studies have recently shown in translatome analysis that the mTOR pathway preferentially regulates the translation of mRNAs encoding ribosomal proteins and translation factors. Therefore, the role of the mTOR pathway in the control of protein synthesis extends far beyond immediate translational control. By controlling ribosome production (and ultimately ribosome availability), mTOR is a master long-term controller of protein synthesis. Herein, we review the literature spanning the early discoveries of mTOR on translation to the latest advances in our understanding of how the mTOR pathway controls the synthesis of ribosomal proteins.

SummarymRNA translation is thought to be the most energy-consuming process in the cell. Translation and energy metabolism are dysregulated in a variety of diseases including cancer, diabetes, and heart disease. However, the mechanisms that coordinate translation and energy metabolism in mammals remain largely unknown. The mechanistic/mammalian target of rapamycin complex 1 (mTORC1) stimulates mRNA translation and other anabolic processes. We demonstrate that mTORC1 controls mitochondrial activity and biogenesis by selectively promoting translation of nucleus-encoded mitochondria-related mRNAs via inhibition of the eukaryotic translation initiation factor 4E (eIF4E)-binding proteins (4E-BPs). Stimulating the translation of nucleus-encoded mitochondria-related mRNAs engenders an increase in ATP production capacity, a required energy source for translation. These findings establish a feed-forward loop that links mRNA translation to oxidative phosphorylation, thereby providing a key mechanism linking aberrant mTOR signaling to conditions of abnormal cellular energy metabolism such as neoplasia and insulin resistance.

The present study assessed emotion regulation in response to chemosensory and visual stimuli. Using cognitive reappraisal, 40 female participants regulated their emotions in response to disgusting pictures and odors, while the startle reflex was elicited and emotion ratings were assessed. Participants reported feeling less negative, and less aroused, while down-regulating their emotions towards both odors and pictures. Although being rated as equally negative and arousing, odor presentations were accompanied by larger startle responses than picture presentations. Furthermore, as compared to pictures emotion regulation towards odors followed a strikingly different time course suggesting less effective emotion regulation in response to disgusting odors. Questionnaire data show that differences between emotion regulation outcome towards odors was not attributable to different regulation strategies used. Thus, the current data suggest a unique role of olfaction in emotion perception, and show that cognitive emotion regulation – although being generally effective – may also be limited.

On an individual level, human body odors carry information about whether a person is an eligible mate. The current studies investigate if body odors also transmit information about individuals being potential partners in more general terms, namely in regards to gender and sexual orientation. In study 1, 14 gay and 14 heterosexual men were presented with body odors obtained from potential partners (gay male and heterosexual female body odors, respectively) and heterosexual male body odor as a control. In study 2, 14 lesbian and 14 heterosexual women were presented with lesbian female and heterosexual male body odors representing body odors of potential partners, and heterosexual female body odor as a control. Central nervous processing was analyzed using chemosensory event-related potentials and current source density analysis (64-channel EEG recording). Gay and heterosexual men responded with shorter P2 latencies to the body odors of their preferred sexual partners, and lesbian women responded with shorter P2 latencies to body odors of their preferred gender. In response to heterosexual male body odors, lesbian women displayed the most pronounced P3 amplitude, and distinct neuronal activation in medial frontal and parietal neocortical areas. A similar pattern of neuronal activation was observed in gay men when presented with heterosexual male body odor. Both the early processing advantage (P2) for desirable partners' body odors as well as the enhanced evaluative processing (P3, CSD) of undesirable partners' body odors suggest that human body odors indeed carry information about individuals being potential partners in terms of gender and sexual orientation.

A structure-based approach was pursued in designing novel bisphosphonate inhibitors of the human farnesyl pyrophosphate synthase (hFPPS). Preliminary SAR and structural evidence for the simultaneous binding of these inhibitors into the isopentenyl pyrophosphate (IPP) and the geranyl pyrophosphate (GPP) substrate sub-pockets of the enzyme are presented.

While the majority of phosphatidylinositol-4, 5-bisphosphate (PI-4, 5-P(2)) in mammalian cells is generated by the conversion of phosphatidylinositol-4-phosphate (PI-4-P) to PI-4, 5-P(2), a small fraction can be made by phosphorylating phosphatidylinositol-5-phosphate (PI-5-P). The physiological relevance of this second pathway is not clear. Here, we show that deletion of the genes encoding the two most active enzymes in this pathway, Pip4k2a and Pip4k2b, in the liver of mice causes a large enrichment in lipid droplets and in autophagic vesicles during fasting. These changes are due to a defect in the clearance of autophagosomes, which halts autophagy and reduces the supply of nutrients salvaged through this pathway. Similar defects in autophagy are seen in nutrient-starved Pip4k2a(−/−)Pip4k2b(−/−) mouse embryonic fibroblasts and in C. elegans lacking the PI5P4K ortholog. These results suggest that this alternative pathway for PI-4, 5-P(2) synthesis evolved, in part, to enhance the ability of multicellular organisms to survive starvation.

Although olfactory identification deficits in schizophrenia have been repeatedly demonstrated, some studies indicate that schizophrenia patients may also show an olfactory hypersensitivity. In addition, recent evidence points to impaired odor hedonics in schizophrenia. It was the aim of the present study to investigate olfactory information processing in schizophrenia patients with positive symptoms, by means of chemosensory event-related potential (CSERP) analysis. To control for modality-specific effects, these data were compared to visual event-related potentials (VERP), and in order to control for disorder-specific effects, the schizophrenia patients were compared to healthy controls as well as to patients with major depressive disorder (MDD). In each group, nine subjects were investigated. During EEG recording (32 scalp locations) two odors (positive valence: phenyl-ethylalcohol, negative valence: isobutyraldehyde) were presented using the constant flow method. Afterwards, two colors (red, yellow) were presented. The schizophrenia patients responded to both odors with shorter CSERP latencies than healthy controls and MDD-patients. This effect was most pronounced for the early processing (N1 component) of the emotionally negative odor. However, in response to colors, schizophrenia patients showed increased N1 latencies and a reduced P3 amplitude. It will be discussed whether schizophrenia patients with positive symptoms show a general processing advantage for emotionally negative (threat-related) information.

ATM gene alterations have been described in various lymphoproliferative malignancies suggesting that ATM contributes to lymphomagenesis. Using multiplex ligation-dependant probe amplification (MLPA), we screened 61 childhood lymphoid malignancies for ATM genomic deletion/duplication. Five samples were found to have a complete deletion or duplication. All the three deletions were found in B-precursor ALL (15%), two were submicroscopic, not detected by standard cytogenetic studies. These observations indicate that as in adult ALL, complete ATM submicroscopic deletion is frequent in childhood B-precursor ALL. As previously hypothesized, these results suggest that ATM may act as a tumor suppressor gene in the pathogenesis of childhood B-precursor ALL.

The aim of the present study was to investigate whether chemosensory anxiety signals can activate behavioral withdrawal systems in humans. Twelve male university students donated their axillary sweat in two situations: right before an oral academic examination (anxiety condition) and during ergometric training (exercise condition). Subjective ratings revealed that the odor donors experienced significantly more anxiety and less pleasure during the anxiety condition than during the exercise condition. Seven subjects (three females) participated in the psychophysiological experiment. The chemosensory stimuli from pooled sweat samples of the donors, and from unused cotton pads (pad condition) were presented via a constant-flow olfactometer. Acoustic startle probes (100 dB (A)) were delivered during and between the presentations of the chemosensory stimuli. Only three subjects were able to discriminate the chemosensory stimuli of the human sweat samples from room air. However, the startle reflex amplitude (EMG of the eyeblink response) recorded in the context of chemosensory anxiety signals was increased, as compared to the amplitude recorded in the context of chemosensory stimuli from either exercise (p = 0.018) or cotton pad (p = 0.012). It is concluded that chemosensory anxiety signals may pre-attentively prime defensive behavior.

Pohl M, Ruckriem S, Strik H, Hortinger B, Meiβner D, Mehrholz J, Pause M. Treatment of pressure ulcers by serial casting in patients with severe spasticity of cerebral origin. Arch Phys Med Rehabil 2002;83:35-9. Objective: To assess the effectiveness of serial casting in the treatment of pressure ulcers caused by severe spasticity. Design: Case series. Setting: A clinic for the rehabilitation of persons with neurologic disorders. Patients: Nine patients with 11 pressure ulcers resulting from severe cerebral spasticity, the ulcers being intractable to conventional management because of repeated friction and/or inaccessibility. Intervention: Serial casting of the limb(s) with the pressure ulcer(s), with either fenestration or a cast arch providing access to the wound. Main Outcome Measures: Improved healing of pressure ulcers, as quantified with the National Pressure Ulcer Advisory Panel classification system. Results: Within a mean of 4.6 weeks, 7 ulcers healed completely and 4 improved markedly. The casting caused no complications. Moreover, extension deficits improved markedly in all patients (105° ± 27° to 17° ± 10°). Conclusion: Serial casting may be a valuable tool in the treatment of pressure ulcers at the extremities of patients with severe cerebral spasticity. © 2002 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation

The aim of the present study is to investigate olfactory sensitivity and odor evaluations in a homogenous sample of unipolar depressive patients using pure olfactory odors. Twenty-four in-patients with major depressive disorder (MDD) were investigated during their acute depressive phase. Eighteen of them participated a second time after successful treatment. A group of healthy subjects, matched by age, sex, and smoking behavior, served as a control. Olfactory sensitivity, as measured by threshold tests, was strongly reduced in patients with severe depression. Additional correlative analyses revealed that the lowered sensitivity could partly be predicted by high depression scores. After successful medical treatment, these sensitivity differences were reduced and did not reach the significance level. The subjective odor evaluations (valence and intensity ratings) were not markedly changed in general. The results reveal that olfactory performance in MDD patients is reduced at an early perceptional level of stimulus processing. It is discussed whether this effect can be attributed to the close functional connection between the main olfactory bulb and the amygdala.

Objective : The aim of the study was to determine how odor processing is altered in patients with unilateral supratentorial brain tumors. Methods : Olfactory event-related potentials (OERPs) were evaluated in 10 patients with unilateral brain tumors of the frontal or temporal lobe in response to linalool and allylcaproate. Both odors were presented monorhinally by a constant-flow olfactometer. In addition, 20 healthy subjects were examined. While sniffing, the subjects were asked to discriminate the two odors. EEG was recorded from 7 electrode positions (Fz, Cz, Pz, F3/4, P3/4). Amplitudes and latencies of 3 peaks (N1, P2, P3) were measured. To control for effects of modality-non-specific alterations on the olfactory components acoustic event-related potentials (AERPs) were registered by use of an oddball paradigm. Results : Patients with right-sided lesions showed distinct deficits in the discrimination task after stimulation of the right and left nostril. In contrast, patients with left-sided lesions only had an attenuation of correct reactions after left-sided stimulation. In the OERPs, patients with right-sided lesions showed P2- and P3-components with decreased amplitudes at parietal electrode positions. These alterations appeared after ipsi- and contralateral stimulation. Patients with left-sided lesions showed a significant effect of the side of stimulation. Their OERP-amplitudes were decreased after left-sided stimulation but not after right-sided stimulation. After right-sided olfactory stimulation a correlation between the olfactory and the acoustic ERP was seen in patients with right-sided lesions. Conclusions : Olfactory performance of the participating patients was markedly reduced. Patients with right-sided lesions showed bilateral impairment, which would support the importance of the right hemisphere in olfaction. The alteration of the topographic distribution of P2- and P3-amplitudes in patients with right-sided lesions might reflect an impairment of early and late olfactory processing steps.

Environmental cocontamination by polycyclic aromatic hydrocarbons (PAHs) and metals could affect the carcinogenic consequences of PAH exposure by modifying PAH induction of PAH-bioactivating CYP1A. The effect of As, Pb, Hg, or Cd (ranked as the most hazardous environmental metals by EPA and ATSDR) on CYP1A1 and 1A2 induction by benzo[a]pyrene (BaP), benzo[b]fluoranthene (BbF), dibenzo[a,h]anthracene (DBahA), benzo[a]anthracene (BaA), and benzo[k]fluoranthene (BkF) has thus been investigated in fresh human hepatocyte cultures. Induction was probed by ethoxyresorufin-O-deethylase activity, by immunoblots, and by RT-PCR. Uptake of PAHs into the hepatocytes varied according to PAH and liver donor: 84% of 5 microM BaA and 25-40% of 5 microM DBahA was taken up in 24 h. Hepatocytes retained viability up to 1 microM Cd and 5 microM Pb, Hg, or As and 5 microM PAHs. PAH induction of CYP1A in hepatocytes was variable, some cultures expressed CYP1A1 and others CYP1A1 and 1A2, and to variable extents. Induction efficiency (relative to DMSO controls) at 2.5 microM PAH concentration was in the order BkF (7.6-fold) > DBahA (6.1 fold) > BaP (5.7 fold) > BbF (3.9-fold) > BaA (2.5-fold). All four metals (1-5 microM) decreased CYP1A1/1A2 induction by some of the PAHs with dose-, metal-, and PAH-dependency. Arsenic (5 microM) decreased induction by 47% for BaP, 68% for BaA, 45% for BbF, 79% for BkF, and 53% for DBahA. Induced CYP1A2 protein was much more extensively decreased than 1A1 protein, and CYP1A2 mRNA and, to variable extents, CYP1A1 mRNA were decreased by As. Thus the metals in PAH/metal mixtures could diminish PAH carcinogenicity by decreasing induction of their bioactivation by CYP1A1/1A2.

Androstenone is a boar pheromone. and has also been found within different human body fluids. However, it is still unclear whether it carries pheromonal information in humans and whether it contributes significantly to the complex human body odor at all. Some humans fail to perceive the odor of androstenone, but most of these anosmics can achieve sensitivity by daily sniffing. The following study was designed to investigate whether sensitivity to androstenone influences the perception of body odors. Four females osmic to and four females anosmic to androstenone attended two EEG sessions. Anosmics were successfully sensitized to androstenone between sessions. CSERPs (chemosensory event-related potentials) were obtained while subjects perceived their own body odor and a male body odor within an olfactory oddball paradigm. The CSERPs showed a general decrease in amplitude from the first to the second session except for the sensitized anosmics in response to male body odor. The results indicate that the sensitivity to androstenone in females is associated with a stronger brain response to male body odor.

This paper addresses two questions related to the inherent association between breathing and odor perception: Does central nervous processing of odors change when an artificial breathing technique (velopharyngeal closure) is introduced and secondly, does odor processing vary with the oral breathing phase (inhalation or exhalation)? Chemosensory event-related potentials (CSERP) were obtained from eight female subjects while they were smelling an odor mixture (citral, eugenol, linalool, menthol and isoamylacetate). Each subject was required to perform spontaneous mouth breathing (120 trials) as well as the velopharyngeal closure technique (120 trials). Simultaneously, a thermistor monitored the phase of the respiratory cycle. The results reveal that the central nervous correlates of odor processing change with the breathing technique but not with the oral breathing cycle. The findings that early stimulus processing is faster (N1 latency) and late stimulus processing more pronounced (P3 amplitudes) when the subjects are breathing spontaneously are discussed with regard to attentional effects. The reduction of the N1 amplitude during the spontaneous breathing condition may be caused by larger latency variations and longer stimulus rise-times. Furthermore, it is concluded that the oral breathing cycle is less important than the nasal breathing cycle for olfactory information transmission.

Even though perceptional abilities have repeatedly been found to be associated with certain personality styles (e.g., extraversion), such connections were reported sparsely for the olfactory modality. Two studies were carried out to investigate the relationship between olfactory sensitivity and 12 personality dimensions (including extraversion and neuroticism). In the first study, single olfactory measurements were compared to repeated measurements. In the second study, twins were recruited as subjects to also examine the heredity of olfactory sensitivity. The results indicate that neuroticism is a stronger predictor for olfactory sensitivity than extraversion. Repeated measurements seem to be necessary to obtain valid data on olfactory performance.