Conservation of magnetite biomineralization genes in all domains of life and implications for magnetic sensing.

Animals use geomagnetic fields for navigational cues, yet the sensory mechanism underlying magnetic perception remains poorly understood. One idea is that geomagnetic fields are physically transduced by magnetite crystals contained inside specialized receptor cells, but evidence for intracellular, biogenic magnetite in eukaryotes is scant. Certain bacteria produce magnetite crystals inside intracellular compartments, representing the most ancient form of biomineralization known and having evolved prior to emergence of the crown group of eukaryotes, raising the question of whether magnetite biomineralization in eukaryotes and prokaryotes might share a common evolutionary history. Here, we discover that salmonid olfactory epithelium contains magnetite crystals arranged in compact clusters and determine that genes differentially expressed in magnetic olfactory cells, contrasted to nonmagnetic olfactory cells, share ancestry with an ancient prokaryote magnetite biomineralization system, consistent with exaptation for use in eukaryotic magnetoreception. We also show that 11 prokaryote biomineralization genes are universally present among a diverse set of eukaryote taxa and that nine of those genes are present within the Asgard clade of archaea Lokiarchaeota that affiliates with eukaryotes in phylogenomic analysis. Consistent with deep homology, we present an evolutionary genetics hypothesis for magnetite formation among eukaryotes to motivate convergent approaches for examining magnetite-based magnetoreception, molecular origins of matrix-associated biomineralization processes, and eukaryogenesis.

Effects of star anise (Illicium verum Hook.f.) essential oil on laying performance and antioxidant status of laying hens.

To investigate the effects of dietary supplementation of star anise oil (SAO) on performance and antioxidant status of laying hens, a total of 864 Hy-Line brown laying hens at 26 wk of age were randomly allocated to 4 treatments with 6 replicates of 36 birds. Dietary treatments were non-star anise oil supplementation and supplemented with SAO at the level of 200, 400, and 600 mg/kg diet. The birds were fed the diets for 56 d. Average egg weight, average daily feed intake (ADFI), egg mass, laying rate, and feed conversion of each replicate were measured. Blood and liver samples from 12 birds were obtained, 72 eggs were picked out, per treatment at day 28 and day 56 of the experiment, and eggs stored for 56 d, to determine antioxidant status in serum, liver, and yolk. All laying hens had similar average egg weight, egg mass, laying rate, and feed conversion in day 29 to day 56 or the entire period of the experiment but significant difference on ADFI in day 1 to day 56. However, increasing diet concentration of SAO tended to improve (P < 0.10) egg mass, average egg weight, and ADFI in day 1 to day 28. Supplementation of SAO linearly increased (P < 0.05) activities of total superoxide dismutase (T-SOD) (day 28 and day 56) and glutathione peroxidase (GSH-PX) (day 56) in serum, GSH-PX (day 28 and day 56) in liver and total antioxidant capacity (T-AOC) (day 56) in serum and liver, but linearly reduced (P < 0.05) concentrations of malondialdehyde (MDA) (day 28 and day 56) in liver. Supplementation of SAO linearly increased (P < 0.05) T-SOD activity at day 14 and day 28, reduced (P < 0.05) MDA concentration at day 42 and day 56 of the experiment in yolk. Increasing content of SAO linearly (P < 0.05) increased T-SOD activity in yolk of eggs stored at day 0, 14, 28, 42, and 56, decreased MDA content of eggs stored at day 42 and 56, whether laying hens fed diets for 28 or 56 d. Dietary supplementation of SAO enhanced laying performance and overall antioxidant status of laying hens in a dose-dependent manner.

The role of complement system in septic shock.

Septic shock is a critical clinical condition with a high mortality rate. A better understanding of the underlying mechanisms is important to develop effective therapies. Basic and clinical studies suggest that activation of complements in the common cascade, for example, complement component 3 (C3) and C5, is involved in the development of septic shock. The involvement of three upstream complement pathways in septic shock is more complicated. Both the classical and alternative pathways appear to be activated in septic shock, but the alternative pathway may be activated earlier than the classical pathway. Activation of these two pathways is essential to clear endotoxin. Recent investigations have shed light on the role of lectin complement pathway in septic shock. Published reports suggest a protective role of mannose-binding lectin (MBL) against sepsis. Our preliminary study of MBL-associated serine protease-2 (MASP-2) in septic shock patients indicated that acute decrease of MASP-2 in the early phase of septic shock might correlate with in-hospital mortality. It is unknown whether excessive activation of these three upstream complement pathways may contribute to the detrimental effects in septic shock. This paper also discusses additional complement-related pathogenic mechanisms and intervention strategies for septic shock.

Coadministration of NXY-059 and tenecteplase six hours following embolic strokes in rabbits improves clinical rating scores.

Currently, the only FDA-approved treatment for acute ischemic stroke (AIS) is the thrombolytic, tissue plasminogen activator (tPA; alteplase; activase). It has been proposed that both the spin trap agent NXY-059 (cerovive) and tenecteplase (TNK-tPA), which are currently in phase II clinical trials, may also be useful for the treatment of ischemic stroke. However, there is little information available concerning the dose-response profiles or therapeutic window for NXY-059 in a validated embolic stroke model, nor is there information available pertaining to the effects of combining NXY-059 with tenecteplase. Thus, we determined the pharmacological profile of NXY-059 on behavioral outcome following small clot embolic strokes in rabbits when administered alone or in combination with tenecteplase. Male New Zealand white rabbits were embolized by injecting a suspension of small blood clots into cerebral circulation via a carotid catheter. NXY-059 (0.1-100 mg/kg) was infused intravenously (IV), 1 h following embolization, whereas control rabbits received infusions of saline. We also determined the therapeutic window for NXY-059 by administering the drug 1, 3, or 6 h following embolic strokes. Lastly, in combination studies, NXY-059 was given concomitantly with tenecteplase 1 or 6 h following embolization. In the vehicle control group, the P(50) value (milligrams of clots that produce behavioral deficits in 50% of the rabbits) measured 24 h following embolism was 1.20 +/- 0.15 mg, and this was increased by 100-134% if NXY-059 (1-100 mg/kg) was administered following embolization. If NXY-059 was administered beginning 3 or 6 h following embolization, there was no significant behavioral improvement. If NXY-059 (100 mg/kg) and tenecteplase (0.9 mg/kg) were administered concomitantly 1 h postembolization, we did not measure any additional behavioral improvement compared to either drug alone. However, if the drugs were administered 6 h following embolization, we measured a statistically significant reduction of behavioral deficits. This study shows that NXY-059 is neuroprotective over a wide range if administered early following an embolic stroke. In addition, the study shows that NXY-059 can be administered in combination with tenecteplase to provide additional behavioral improvement at extended delays following embolization.

Pharmacology of caffeinol in embolized rabbits: clinical rating scores and intracerebral hemorrhage incidence.

Caffeinol is currently being tested in acute ischemic stroke patients. However, little is known about the pharmacology or safety of caffeinol in preclinical embolic stroke models. We determined the pharmacological effects of caffeinol administration on clinical rating scores in rabbits following small clot embolic strokes (RSCEM). Male New Zealand white rabbits were embolized by injecting blood clots into the cerebral circulation via a carotid catheter. Behavioral analysis was conducted 24 h following embolization, allowing for the determination of the effective stroke dose (P50) or clot amount (mg) that produces neurological deficits in 50% of the rabbits. In the current study, the P50 values for the control groups were 1.32 +/- 0.23 and 1.66 +/- 0.29 mg for the bolus-injected and infused groups, respectively. Rabbits treated with caffeinol (bolus) starting 15 min following embolization had a P50 value of 1.70 +/- 1.18 mg. Caffeinol-infused rabbits had a P50 value of 2.05 +/- 0.47 and 1.67 +/- 0.48 mg for low- and high-dose ethanol, respectively. In tPA-treated rabbits (0.9 mg/kg), the group P50 was 1.58 +/- 0.43 mg. In caffeinol (bolus) and tPA-treated rabbits, we measured a decrease in the P50 value to 0.70 +/- 0.30 mg and an increase in the rate of intracerebral hemorrhage compared to control. This primary finding of this study indicates that neither bolus-injected nor infused caffeinol affects behavioral deficits following embolic strokes in rabbits. Moreover, the combination of caffeinol plus low-dose tPA does not improve behavioral deficits. However, our study suggests that there is the potential for exacerbation of stroke-induced behavioral deficits following caffeinol administration in combination with a thrombolytic that may be related to increased intracerebral hemorrhage.

Transcranial infrared laser therapy improves clinical rating scores after embolic strokes in rabbits.

BACKGROUND AND PURPOSE: Because photon energy delivered using a low-energy infrared laser may be useful to treat stroke, we determined whether transcranial laser therapy would improve behavioral deficits in a rabbit small clot embolic stroke model (RSCEM). METHODS: In this study, the behavioral and physiological effects of laser treatment were measured. The RSCEM was used to assess whether low-energy laser treatment (7.5 or 25 mW/cm2) altered clinical rating scores (behavior) when given to rabbits beginning 1 to 24 hours postembolization. Behavioral analysis was conducted from 24 hours to 21 days after embolization, allowing for the determination of the effective stroke dose (P50) or clot amount (mg) that produces neurological deficits in 50% of the rabbits. Using the RSCEM, a treatment is considered beneficial if it significantly increases the P50 compared with the control group. RESULTS: In the present study, the P50 value for controls were 0.97+/-0.19 mg to 1.10+/-0.17 mg; this was increased by 100% to 195% (P50=2.02+/-0.46 to 2.98+/-0.65 mg) if laser treatment was initiated up to 6 hours, but not 24 hours, postembolization (P50=1.23+/-0.15 mg). Laser treatment also produced a durable effect that was measurable 21 days after embolization. Laser treatment (25 mW/cm2) did not affect the physiological variables that were measured. CONCLUSIONS: This study shows that laser treatment improved behavioral performance if initiated within 6 hours of an embolic stroke and the effect of laser treatment is durable. Therefore, transcranial laser treatment may be useful to treat human stroke patients and should be further developed.

[Synthesis of azobenzol compound and analytical application in a new catalytic spectrophotometry system].

Analysis of the indicator synthesis was studied by catalytic spectrophotometry, and the reducing decolorization that the copper(II) catalyzed the ration between ascorbic acid and 3-methyl-4-amino-4'-nitro azobenzol was discussed. Reaction condition was optimized and a highly selective determination of trace copper(II) was established. The detection limit was 0.048 microgram.L-1 for copper (II). The method has been used for determining trace copper(II) in human hair and aluminum alloy samples with satisfactory results.

Effects of intrathecal administration of a cell permeant caspase inhibitor, boc-D-fluoromethylketone (BDFMK), on behavioral deficits following spinal cord ischemia: a dose-response analysis.

Caspase inhibition has been proposed as a target to attenuate ischemia-induced neurodegeneration and behavioral dysfunction. The present study evaluated the pharmacological effects of a single dose of an irreversible cell permeant general (nonselective) caspase inhibitor, Boc-D-fluoromethylketone (BDFMK) administered intrathecally (i.t.) in a reversible spinal cord ischemia model (RSCIM). Quantal analysis indicated that the P(50) (represents the duration of ischemia that produces permanent paraplegia in 50% of the animals in a group) of the control group was 25.08+/-4.71 min. Using the RSCIM, neuroprotection is observed if a drug significantly prolongs the P(50) compared to the control group. The P(50) values for the BDFMK-treated groups were 27.21+/-2.62, 27.28+/-3.29 and 28.98+/-2.32 min, for the three dose groups studied. There were no statistically significant changes when measured 18 or 48 h following ischemia. Biochemical analysis of cell extracts from the caudal lumbar spinal cord indicated that there was increased production of the 120-kDa fragment of fodrin suggesting enhanced caspase-3 activity, an increase that was reduced by i.t. BDFMK administration. Moreover, in caudal lumbar spinal cord extracts from a set of paraplegic rabbits (25-50 min occlusion), we measured a 32-42% decrease of caspase-3 activity in BDFMK-treated rabbits. The present study shows that i.t. administration of BDFMK reduced caspase-3 activity, but the inhibition did not translate into a significant behavioral improvement. Our results suggest that administration of a single dose of the caspase inhibitor BDFMK is insufficient to attenuate ischemia-induced behavioral deficits following aortic occlusion.

Microplasmin: a novel thrombolytic that improves behavioral outcome after embolic strokes in rabbits.

BACKGROUND AND PURPOSE: It has been proposed that the novel thrombolytic microplasmin may be useful in the treatment of ischemic stroke. In the present study the effects and safety profile of microplasmin were evaluated in 2 rabbit embolic stroke models that have been used successfully to develop tissue plasminogen activator (tPA) as the only Food and Drug Administration-approved treatment for stroke. The rabbit small clot embolic stroke model (RSCEM) and rabbit large clot embolic stroke model (RLCEM) were used to determine the potential neuroprotective properties and safety profile of microplasmin, respectively, after an embolic stroke. METHODS: Rabbits were embolized by injecting small blood clots (RSCEM) or large blood clots (RLCEM) into the cerebral circulation. For the RSCEM, 126 rabbits were included, with behavioral analysis conducted 24 hours later, allowing for determination of the effective stroke dose (ES50) or clot amount (milligrams) that produces severe neurological deficits in 50% of rabbits. For RLCEM safety study analysis, 47 rabbits were included, with postmortem analyses consisting of assessment of hemorrhage and infarct rate and size. In test animals microplasmin was infused intravenously 60 minutes after embolization, whereas control rabbits were given infusions of the saline/Plasma-Lyte vehicle with all assessments performed in a blinded fashion. RESULTS: In the RSCEM, a drug is considered neuroprotective if it significantly increases the ES50 compared with the vehicle-treated control group. The ES50 of the vehicle-treated control group 24 hours after embolization was 1.36+/-0.42 mg (n=38). Microplasmin, infused starting 60 minutes after embolization, increased the ES50 to 2.32+/-0.57 (n=21), 1.89+/-0.48 (n=21), 2.81+/-0.55 (n=22), and 1.89+/-0.28 mg (n=24) for the 1-, 2-, 4-, and 8-mg/kg doses, respectively. There was a statistically significant behavioral improvement in the 4-mg/kg dose arm (P=0.040). The microplasmin dose of microplasmin that was statistically significant (4 mg/kg) was subsequently determined to be safe in the RLCEM because it did not increase the incidence of hemorrhages (56%) compared with vehicle-treated rabbits (63%), nor did it significantly alter hemorrhage volume, infarct rate, or infarct volume. CONCLUSIONS: The present study shows that microplasmin improves behavioral rating scores in the RSCEM when administered 60 minutes after embolization, at a dose that does not increase hemorrhages in the RLCEM. This is in contrast to tPA, which significantly enhances the hemorrhage rate in the RLCEM.

Effects of the spin trap agent disodium- [tert-butylimino)methyl]benzene-1,3-disulfonate N-oxide (generic NXY-059) on intracerebral hemorrhage in a rabbit Large clot embolic stroke model: combination studies with tissue plasminogen activator.

BACKGROUND AND PURPOSE: It has been proposed that the novel spin trap agent disodium-[(tert-butylimino)methyl]benzene-1,3-disulfonate N-oxide (NXY-059) may be useful in the treatment of ischemia and stroke. To date, there is little information concerning the safety of NXY-059 when administered in combination with the only Food and Drug Administration-approved pharmacological agent for the treatment of stroke, the thrombolytic tissue plasminogen activator (tPA). Thus, we determined the effects of NXY-059G, a generic form of NXY-059, on hemorrhage and infarct rate and volume when administered alone or in combination with tPA. In addition, we determined whether NXY-059G affected 2 physiological variables, blood glucose levels and body temperature. METHODS: Male New Zealand White rabbits were embolized by injecting a large blood clot into the middle cerebral artery via a catheter. Five minutes after embolization, NXY-059G (100 mg/kg) was infused intravenously; control rabbits received infusions of saline, the vehicle required to solubilize NXY-059G. In tPA studies, the thrombolytic was administered intravenously starting 60 minutes after embolization (20% bolus injection/80% infusion over 30 minutes). Body temperature and blood glucose levels were measured throughout the study. Postmortem analysis included assessment of hemorrhage and infarct rate, size, and location. RESULTS: In the vehicle control group, the hemorrhage rate after a thromboembolic stroke was 52% (n=23), and this was increased by 67% if tPA was administered (n=15). The rabbits treated with NXY-059G in the absence of tPA had a 79% incidence of hemorrhage (n=19), an increase of 52% over the control group. In the combination drug-treated groups, the NXY-059G/tPA group had a 47% incidence of hemorrhage (n=15). There was a decrease of hemorrhage volume in the NXY-059G+tPA group compared with the other 3 groups included in the study. There was no significant effect of NXY-059G either alone or in combination with tPA on infarct rate or volume. NXY-059G did not significantly alter the physiological variables that were measured. CONCLUSIONS: This study suggests that NXY-059G may affect the integrity of the cerebral vasculature when administered immediately after an embolic stroke, as evidenced by an increase in hemorrhage rate. However, when NXY-059G is administered in combination with tPA, it may improve the safety of tPA by reducing the incidence of tPA-induced hemorrhage. The mechanism(s) involved in the NXY-059G-induced increase in hemorrhage rate and reduction of tPA-induced hemorrhage rate remains to be elucidated.

Neuroprotective effects of the spin trap agent disodium-[(tert-butylimino)methyl]benzene-1,3-disulfonate N-oxide (generic NXY-059) in a rabbit small clot embolic stroke model: combination studies with the thrombolytic tissue plasminogen activator.

BACKGROUND AND PURPOSE: It has been proposed that the novel spin trap agent disodium-[(tert-butylimino)methyl]benzene-1,3-disulfonate N-oxide (NXY-059) may be useful in the treatment of ischemic stroke. However, there is little information concerning the neuroprotective properties of NXY-059 when administered after an embolic stroke. Moreover, there is no information available concerning the combination of NXY-059 with the only Food and Drug Administration-approved pharmacological agent for the treatment of acute stroke, the thrombolytic tissue plasminogen activator (tPA). Thus, we determined the effects of NXY-059G, a generic form of NXY-059, on behavioral outcome after an embolic stroke when administered alone or in combination with tPA. METHODS: Male New Zealand White rabbits were embolized by injecting a suspension of small blood clots into cerebral circulation via a carotid catheter. NXY-059G (100 mg/kg) was infused intravenously 5 minutes or 3 hours after embolization, whereas control rabbits received infusions of the saline vehicle. In tPA studies, the thrombolytic was administered intravenously starting 60 minutes or 3 hours after embolization (3.3 mg/kg). In combination studies, NXY-059G was given 5 minutes after embolization, followed by the administration of tPA beginning either 60 minutes or 3 hours after embolization. Behavioral analysis was conducted 24 hours after embolization. RESULTS: In the vehicle control group, the ES50 value (calculated as the amount of microclots [milligrams] that produce neurological dysfunction [impairment] in 50% of the rabbits within a specific treatment group) measured 24 hours after embolism was 1.04+/-0.31 mg, and this was increased by 153% to 2.54+/-0.72 mg if NXY-059G was administered beginning 5 minutes after embolization. However, if NXY-059G was administered beginning 3 hours after embolization, the ES50 was 2.01+/-0.40 mg. The rabbits treated with tPA alone had an ES50 of 2.64+/-0.66 or 0.63+/-0.35 mg if tPA administration started 60 minutes or 3 hours after embolization, respectively. If tPA was administered after NXY-059G (started at 5 minutes), the ES50 values were 3.15+/-0.50 or 2.66+/-0.82 if tPA administration started 60 minutes or 3 hours after embolization, respectively. CONCLUSIONS: This study suggests that NXY-059G is neuroprotective and can increase behavioral ratings if administered early after an embolic stroke. In addition, the study shows that NXY-059G can be used in combination with tPA without negative side effects. The drug combination can improve behavioral function and increase ES50 values. However, during the short time course of the behavioral analysis, the combination was not statistically better than either drug alone.