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With climate change, pea will be more frequently subjected to heat stress in semi-arid regions like Saskatchewan during flowering. The pollen germination percentage of two pea cultivars was reduced by heat stress (36°C) with an important decrease in cultivar ‘CDC Golden’ compared to ‘CDC Sage.’ Lipids, protein and other pollen coat compositions of whole intact pollen grains of both pea cultivars were investigated using mid infrared (mid-IR) attenuated total reflectance (ATR)–Fourier transform infrared (FTIR) spectroscopy. Curve fitting of ATR absorbance spectra in the protein region enabled estimation and comparison of different protein secondary structures between the two cultivars. CDC Sage had relatively greater amounts of α-helical structures (48.6–43.6%; band at 1654 cm-1) and smaller amounts of β-sheets (41.3–46%) than CDC Golden. The CDC Golden had higher amounts of β-sheets (46.3–51.7%) compared to α-helical structures (35.3–36.2%). Further, heat stress resulted in prominent changes in the symmetrical and asymmetrical CH2 bands from lipid acyl chain, ester carbonyl band, and carbohydrate region. The intensity of asymmetric and symmetric CH2 vibration of heat stressed CDC Golden was reduced considerably in comparison to the control and the decrease was higher compared to CDC Sage. In addition, CDC Golden showed an increase in intensity at the oxidative band of 3015 cm-1. These results reveal that the whole pollen grains of both pea cultivars responded differently to heat stress. The tolerance of CDC Sage to heat stress (expressed as pollen germination percentage) may be due to its protein richness with α-helical structures which would protect against the destructive effects of dehydration due to heat stress. The low pollen germination percentage of CDC Golden after heat stress may be also due to its sensitivity to lipid changes due to heat stress.

A hydrofluoric acid (HF)-free solvothermal method was used to synthesize nanoscale metal–organic framework NMIL-100­(Fe), which exhibited comparable physicochemical properties as those prepared by traditional methods, but with a mild and environmentally benign synthesis condition. XRD, TGA, N2 adsorption, FT-IR, SEM, and TEM were employed to characterize the as-prepared NMIL-100­(Fe), which was further applied as an effective adsorbent for dye adsorption, including two cationic dyes, rhodamine 6G (R6G) and rhodamine B (RB), and an anionic reactive red 120 (RR 120) with high adsorption efficiencies and capacities. The adsorption process can be well described by pseudo-second-order kinetic model and Langmuir isotherm model. Hydrogen bonding and electrostatic interaction were revealed for the adsorption of the two cationic dyes and one anionic dye onto NMIL-100­(Fe), respectively, as investigated by mechanism studies. Thermodynamic analyses indicate that adsorption processes for cationic and anionic dyes are entropy-driven endothermic and enthalpy-driven exothermic processes, respectively. This environmental-benign synthetic strategy for NMIL-100­(Fe), as well as its high adsorption efficiency and capacity, might be used for the fabrication of other nanoscale metal–organic frameworks, and the potential applications of NMIL-100­(Fe) in real wastewater treatment.

Although exogenous serotonin at the hypoglossal motor nucleus (HMN) activates the genioglossus muscle, endogenous serotonin plays a minimal role in modulating genioglossus activity in awake and sleeping rats (Sood S, Morrison JL, Liu H, and Horner RL. Am J Respir Crit Care Med 172: 1338-1347, 2005). This result therefore implies that medullary raphe neurons also play a minimal role in the normal physiological control of the HMN, but this has not yet been established because raphe neurons release other excitatory neurotransmitters onto respiratory motoneurons in addition to serotonin. This study tests the hypothesis that inhibition of medullary raphe serotonergic neurons with 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT) suppresses genioglossus and diaphragm activities in awake and sleeping rats. Ten rats were implanted with electrodes to record sleep-wake states and genioglossus and diaphragm activities. Microdialysis probes were also implanted into the nucleus raphe obscurus (NRO). Experiments in 10 anesthetized and vagotomized rats were also performed using the same methodology. In anesthetized rats, microdialysis perfusion of 0.1 mM 8-OH-DPAT into the NRO decreased genioglossus activity by 60.7+/-9.0% and diaphragm activity by 13.3+/-3.4%. Diaphragm responses to 7.5% CO2 were also significantly reduced by 8-OH-DPAT. However, despite the robust effects observed in anesthetized and vagotomized rats, there was no effect of 0.1 mM 8-OH-DPAT on genioglossus or diaphragm activities in conscious rats awake or asleep. The results support the concept that endogenously active serotonergic medullary raphe neurons play a minimal role in modulating respiratory motor activity across natural sleep-wake states in freely behaving rodents. This result has implications for pharmacological strategies aiming to manipulate raphe neurons and endogenous serotonin in obstructive sleep apnea.

Progression of critically ill patients from Systemic Inflammatory Response Syndrome (SIRS) to Multiple Organ Dysfunction Syndrome (MODS) accounts for more than 75% of deaths in adult surgical intensive care units. Currently, there is no practical clinical technique to predict the progression of SIRS or MODS. In this report, we describe an NMR-based metabonomic method to aid detection of these conditions based on abnormal metabolic signatures. We applied pattern recognition methods to analyze one-dimensional (1)H NMR spectra of SIRS and MODS patient sera. By using Principal Component Analysis (PCA) and Partial Least Squares-Discriminant Analysis (PLS-DA), we could distinguish critically ill patients (n = 52) from healthy controls (n = 26). After noise reduction by Orthogonal Signal Correction (OSC), PLS-DA was also able to clearly discriminate SIRS and MODS patients. The corresponding coefficients indicated that spectra responsible for the discrimination were located in delta3.06-3.86 NMR integral regions from SIRS, mainly composed of sugars, amino acids and glutamine signals, and delta1.18-1.3 and delta4.02-4.1 integral regions of MODS serum samples, principally consisted of various proton signals of fatty acyl chains and glycerol backbone of lipids, along with creatinine and lactate. Our results are consistent with the clinical observations that carbohydrate and amino acid levels changes in the early course of critical illness (SIRS stage) and significant disturbances in fat metabolism and development of organ abnormalities become the characteristics in the late stage (MODS). These data suggest that NMR-based metabonomic approach can be developed to diagnose the disease progress of critically ill patients.

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