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1.
Insect Sci ; 29(2): 467-477, 2022 Apr.
Article in English | MEDLINE | ID: mdl-34498794

ABSTRACT

In addition to sperm, some accessory substances transferred to females during copulation act as nuptial gifts by passing on valuable nutrients in many insect species. The nutritional status of the males can thus have a great effect on the mating behavior, fecundity and even the longevity of females. However, little is known about the effect of male nutritional status on the female reproductive traits in migratory insect species, particularly when females experience nutrient shortage and have to choose between reproduction and migration. Here, Cnaphalocrocis medinalis, a migratory rice pest in Asia, was studied to explore this issue. Our results showed that in male moths fed with honey solution, their gonads had higher energy content than gonads of starved males, resulting in increased energy content of the bursa copulatrix of females after mating with fed males. Such females showed increased mating frequency, fecundity and longevity compared to females mating with starved males, indicating that male moths deliver nuptial gifts to females and improve their reproductive performance. However, when females were starved, only about 45% mated, with just a single copulation, regardless of male nutritional status. Starved females showed lower fecundity, and a longer pre-oviposition period (indicating a greater propensity to migrate), compared to fed females. However, copulation still significantly extended their longevity. These results suggest that starved females invest in migration to escape deteriorating habitats, rather than investing the nuptial gift to increased fecundity. Our results further our understanding of the reproductive adaptability of migratory insects under conditions of food stress.


Subject(s)
Moths , Animals , Copulation , Female , Male , Nutrients , Nutritional Status , Reproduction , Sexual Behavior, Animal
2.
Insects ; 11(9)2020 Sep 11.
Article in English | MEDLINE | ID: mdl-32933010

ABSTRACT

Recently, the most serious upsurge of the desert locust (Schistocerca gregaria) in the last 25 years is spreading across eastern Africa and southwestern Asia. Parts of the desert locust 'invasion area', namely the northern border areas of Pakistan and India, are very close to China, and whether locust swarms will invade China is of wide concern. To answer this question, we identified areas of potentially suitable habitat for the desert locust within China based on historical precipitation and temperature data, and found that parts of Xinjiang and Inner Mongolia provinces could provide ephemeral habitat in summer, but these places are remote from any other desert locust breeding areas. New generation adults of the desert locust in Pakistan and India present since April led to swarms spreading into the Indo-Pakistan border region in June, and so we examined historical wind data for this period. Our results showed that winds at the altitude of locust swarm flight blew eastward during April-June, but the wind speeds were quite slow and would not facilitate desert locust eastward migration over large distances. Simulated trajectories of desert locust swarms undertaking 10-day migrations mostly ended within India. The most easterly point of these trajectories just reached eastern India, and this is very close to the eastern border of the invasion area of desert locusts described in previous studies. Overall, the risk that the desert locust will invade China is very low.

3.
Insects ; 11(7)2020 Jul 04.
Article in English | MEDLINE | ID: mdl-32635501

ABSTRACT

Oedaleus asiaticus is one of the dominant species of grasshoppers in the rangeland on the Mongolian plateau, and a serious pest, but its migratory behavior is poorly known. We investigated the take-off behavior of migratory O. asiaticus in field cages in the inner Mongolia region of northern China. The species shows a degree of density-dependent phase polyphenism, with high-density swarming populations characterized by a brown morph, while low-density populations are more likely to comprise a green morph. We found that only 12.4% of brown morphs engaged in migratory take-off, and 2.0% of green morphs. Migratory grasshoppers took off at dusk, especially in the half hour after sunset (20:00-20:30 h). Most emigrating individuals did not have any food in their digestive tract, and the females were mated but with immature ovaries. In contrast, non-emigrating individuals rarely had empty digestive tracts, and most females were mated and sexually mature. Therefore, it seems clear that individuals prepare for migration in the afternoon by eliminating food residue from the body, and migration is largely restricted to sexually immature stages (at least in females). Furthermore, it was found that weather conditions (particularly temperature and wind speed at 15:00 h) in the afternoon had a significant effect on take-off that evening, with O. asiaticus preferring to take off in warm, dry and calm weather. The findings of this study will contribute to a reliable basis for forecasting migratory movements of this pest.

4.
Biomed Environ Sci ; 31(11): 797-804, 2018 Nov.
Article in English | MEDLINE | ID: mdl-30558700

ABSTRACT

OBJECTIVE: To investigate cognitive dysfunction in patients with carotid artery stenosis (CAS) and potential risk factors related to cognitive-especially memory-dysfunction. METHODS: Forty-seven patients with carotid artery stenosis were recruited into our study cohort. The Mini-Mental State Examination (MMSE) and the Montreal Cognitive Assessment (MoCA) were adopted to assess cognitive function, the Wechsler Memory Scale (WMS) to assess memory function, high-resolution MRI and enhanced ultrasound to evaluate carotid plaques, and computed tomography perfusion (CTP) imaging to evaluate intracranial blood perfusion. Single-factor analysis and multiple-factor regression analysis were used to analyze potential risk factors of cognitive impairment. RESULTS: Mini-Mental State Examination test results showed that 22 patients had cognitive impairment, and MoCA test results showed that 10 patients had cognitive impairment. Analysis of various risk factors indicated that the average memory quotient of female patients was higher than that of males (P = 0.024). The cognitive and memory performance of those with an educational background above high school were significantly better than those of participants with high school or lower (P = 0.045). Patients with abnormal intracranial perfusion performed worse on the MMSE test (P = 0.024), and their WMS scores were significantly lower (P = 0.007). The MMSE scores and the memory quotients were significantly lower in patients with a history of cerebral infarction (MMSE, P = 0.047, memory quotient score, P = 0.018). CONCLUSION: A history of cerebral infarction and abnormal cerebral perfusion are associated with decline in overall cognitive function and memory in patients with carotid stenosis. Being female and having an educational background above high school may be protective factors in the development of cognitive dysfunction.


Subject(s)
Carotid Stenosis/complications , Cognitive Dysfunction/etiology , Adult , Aged , China/epidemiology , Cognition , Cognitive Dysfunction/epidemiology , Cognitive Dysfunction/psychology , Cohort Studies , Cross-Sectional Studies , Female , Humans , Male , Memory , Middle Aged , Neuropsychological Tests , Risk Factors
5.
Article in English | WPRIM (Western Pacific) | ID: wpr-772244

ABSTRACT

OBJECTIVE@#To investigate cognitive dysfunction in patients with carotid artery stenosis (CAS) and potential risk factors related to cognitive-especially memory-dysfunction.@*METHODS@#Forty-seven patients with carotid artery stenosis were recruited into our study cohort. The Mini-Mental State Examination (MMSE) and the Montreal Cognitive Assessment (MoCA) were adopted to assess cognitive function, the Wechsler Memory Scale (WMS) to assess memory function, high-resolution MRI and enhanced ultrasound to evaluate carotid plaques, and computed tomography perfusion (CTP) imaging to evaluate intracranial blood perfusion. Single-factor analysis and multiple-factor regression analysis were used to analyze potential risk factors of cognitive impairment.@*RESULTS@#Mini-Mental State Examination test results showed that 22 patients had cognitive impairment, and MoCA test results showed that 10 patients had cognitive impairment. Analysis of various risk factors indicated that the average memory quotient of female patients was higher than that of males (P = 0.024). The cognitive and memory performance of those with an educational background above high school were significantly better than those of participants with high school or lower (P = 0.045). Patients with abnormal intracranial perfusion performed worse on the MMSE test (P = 0.024), and their WMS scores were significantly lower (P = 0.007). The MMSE scores and the memory quotients were significantly lower in patients with a history of cerebral infarction (MMSE, P = 0.047, memory quotient score, P = 0.018).@*CONCLUSION@#A history of cerebral infarction and abnormal cerebral perfusion are associated with decline in overall cognitive function and memory in patients with carotid stenosis. Being female and having an educational background above high school may be protective factors in the development of cognitive dysfunction.


Subject(s)
Adult , Aged , Female , Humans , Male , Middle Aged , Carotid Stenosis , China , Epidemiology , Cognition , Cognitive Dysfunction , Epidemiology , Psychology , Cohort Studies , Cross-Sectional Studies , Memory , Neuropsychological Tests , Risk Factors
6.
J Alzheimers Dis ; 36(4): 637-57, 2013.
Article in English | MEDLINE | ID: mdl-23648515

ABSTRACT

Uridine prodrug PN401 has been shown to have neuroprotective effects in models of Parkinson's disease and Huntington's disease. These age-related neurodegenerative diseases including Alzheimer's disease (AD) are associated with mitochondrial dysfunction, oxidative stress, and inflammation. Attenuation of these pathological factors in AD, in addition to amyloid fibrils and neurofibrillary tangles, is critical to prevent cognitive impairment. The effects of PN401 treatment were tested in the Tg2576 and Tg2576 X P301L (TAPP) mouse models of AD. Treatment with PN401 reduced impairments in the Tg2576 mice in contextual fear conditioning and novel object recognition. In the TAPP mice, PN401 reduced the impairments in novel object recognition and social transmission of food preference. PN401 also improved motor behavior and reduced anxiety-like behavior in the TAPP mice. TAPP mouse hippocampal tau phosphorylation and lipid peroxidation were reduced by PN401 treatment. Increased tau phosphorylation was significantly correlated with worsening novel object recognition memory. PN401 did not affect amyloid plaque area in the AD mice. In other AD-related animal studies, PN401 treatment reduced blood-brain barrier damage due to intracortical LPS, elevation of serum TNFα due to systemic LPS, and hippocampal CA1 neuronal loss in the gerbil stroke model. Uridine dose-dependently protected cells from chemical hypoxia and ceramide, and decreased formation of reactive oxygen species and mitochondrial DNA damage due to hydrogen peroxide. These protective effects were achieved by raising uridine levels to at least 25-50 µM and serum uridine levels in this range in humans were obtained with oral PN401.


Subject(s)
Alzheimer Disease/drug therapy , Disease Models, Animal , Memory/drug effects , Prodrugs/administration & dosage , Uridine/analogs & derivatives , Uridine/administration & dosage , Acetates , Alzheimer Disease/genetics , Alzheimer Disease/pathology , Animals , Cell Line, Tumor , Cricetinae , Female , Gerbillinae , Humans , Male , Maze Learning/drug effects , Maze Learning/physiology , Memory/physiology , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Mice, Transgenic , Stroke/drug therapy , Stroke/pathology
7.
Drug Metab Pharmacokinet ; 28(5): 398-405, 2013.
Article in English | MEDLINE | ID: mdl-23438946

ABSTRACT

The objective of this study was to evaluate the effect of the CYP3A5*3 allele on the pharmacokinetics of tacrolimus and amlodipine, and drug-drug interactions between them in healthy subjects. Pharmacokinetic drug interactions between tacrolimus and amlodipine were evaluated in a randomized, 3-period, 6-sequence crossover study in healthy Chinese volunteers according to CYP3A5 genotype. A single-dose and multiple-dose study were designed. A 96-h pharmacokinetic study followed either tacrolimus or amlodipine dose, and the washout periods between the study phases were 14 days. In the single-dose study, apparent oral clearance (CL/F) of tacrolimus (5 mg) in CYP3A5 expressers was 3.8-fold (p = 0.008) higher than that in CYP3A5 non-expressers. Amlodipine decreased mean tacrolimus CL/F in CYP3A5 expressers by 2.2-fold (p = 0.005), while it had no effect on that in CYP3A5 non-expressers. The CL/F of amlodipine in CYP3A5 non-expressers was 2.0-fold (p = 0.001) higher than that in CYP3A5 expressers. Tacrolimus increased mean amlodipine CL/F in CYP3A5 expressers by 1.4-fold (p = 0.016) while it had no effect on that in CYP3A5 non-expressers. Tacrolimus slightly reduced the AUC0-∞ of amlodipine in both CYP3A5 expressers and non-expressers. Dose adjustment of tacrolimus should be considered according to CYP3A5*3 genetic polymorphism when tacrolimus is coadministered with amlodipine.


Subject(s)
Amlodipine/pharmacokinetics , Cytochrome P-450 CYP3A/genetics , Immunosuppressive Agents/pharmacokinetics , Tacrolimus/pharmacokinetics , Drug Interactions , Humans , Male , Polymorphism, Single Nucleotide , Tacrolimus/administration & dosage , Young Adult
8.
Xenobiotica ; 43(8): 699-704, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23312000

ABSTRACT

1. The immunosuppressant tacrolimus (TAC) is a substrate of cytochrome P450 3A2 (CYP3A2) and P-glycoprotein (P-gp) in rats. Amlodipine (AML) is an inhibitor of CYP3A2 in rats. We investigated the effect of AML on the pharmacokinetics of TAC in rats. 2. When co-administered with TAC orally or intravenously, AML decreased the oral clearance and raised the blood concentration of TAC in rats, but the T1/2 of TAC was not significantly affected by AML. Upon oral administration of TAC, the effect of 15 mg/kg of AML on the AUC of TAC was lower than that seen with 5 or 10 mg/kg. However, upon intravenous TAC administration, the effect of 15 mg/kg of AML on the AUC of TAC was higher than that seen with 5 mg/kg. 3. AML is an inhibitor of P-gp and CYP3A2 in rats. If AML and TAC are co-administered orally, AML elicits greater inhibition in P-gp than CYP3A2 during first-pass metabolism. If AML is given orally and TAC given intravenously concurrently, AML mainly inhibits CYP3A2 activity and increases the blood concentration of TAC. There are significant pharmacokinetic interactions between TAC and AML. AML raises the blood concentration of TAC in rats probably by inhibiting P-gp and CYP3A2.


Subject(s)
Amlodipine/pharmacology , Tacrolimus/pharmacokinetics , Administration, Oral , Animals , Injections, Intravenous , Male , Rats , Rats, Sprague-Dawley , Reproducibility of Results , Tacrolimus/administration & dosage , Tacrolimus/blood
9.
J Neuropathol Exp Neurol ; 66(10): 932-43, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17917587

ABSTRACT

Annexin A1 (ANXA1) has been suggested to be a mediator of the anti-inflammatory actions of glucocorticoids and more recently an endogenous neuroprotective agent. In the present study, we investigated the anti-inflammatory and neuroprotective effects of ANXA1 in a model of contusive spinal cord injury (SCI). Here we report that injections of ANXA1 (Ac 2-26) into the acutely injured spinal cord at 2 concentrations (5 and 20 microg) inhibited SCI-induced increases in phospholipase A2 and myeloperoxidase activities. In addition, ANXA1 administration reduced the expression of interleukin-1beta and activated caspase-3 at 24 hours, and glial fibrillary acidic protein at 4 weeks postinjury. Furthermore, ANXA1 administration significantly reversed phospholipase A2-induced spinal cord neuronal death in vitro and reduced tissue damage and increased white matter sparing in vivo, compared to the vehicle-treated controls. Fluorogold retrograde tracing showed that ANXA1 administration protected axons of long descending pathways at 6 weeks post-SCI. ANXA1 administration also significantly increased the number of animals that responded to transcranial magnetic motor-evoked potentials. However, no measurable behavioral improvement was found after these treatments. These results, particularly the improvements obtained in tissue sparing and electrophysiologic measures, suggest a neuroprotective effect of ANXA1.


Subject(s)
Annexin A1/therapeutic use , Inflammation/prevention & control , Phospholipases A/metabolism , Spinal Cord Injuries/drug therapy , Spinal Cord Injuries/enzymology , Animals , Annexin A1/administration & dosage , Blotting, Western , Cell Survival/drug effects , Cells, Cultured , Electrophysiology , Enzyme Activation/drug effects , Evoked Potentials, Motor/drug effects , Evoked Potentials, Motor/physiology , Female , Gliosis/pathology , Injections, Spinal , Motor Activity/drug effects , Peroxidase/metabolism , Phospholipases A2 , Rats , Rats, Sprague-Dawley , Spinal Cord/enzymology , Spinal Cord/pathology , Spinal Cord Injuries/pathology , Stilbamidines
10.
J Neurosci Methods ; 165(1): 9-17, 2007 Sep 15.
Article in English | MEDLINE | ID: mdl-17628688

ABSTRACT

Assessment of locomotor function of rodents may be supplemented using electrophysiological tests which monitor the integrity of ascending and descending tracts as well as the focal circuitry of the spinal cord in non-sedated rodents. Magnetically induced SSEPs (M-SSEPs) were elicited in rats by activating the hindpaw using magnetic stimulation (MS). M-SSEP response latencies were slightly longer than those elicited by electrical stimulation. M-SSEPs were eliminated following selective dorsal column lacerations of the spinal cord, indicating that they were transmitted via this tract. Magnetically induced motor evoked potentials (M-MEPs) were elicited in mice following transcranial MS and recorded from the gastrocnemius muscles. M-MEPs performed on myelin deficient mice demonstrated longer onset latencies and smaller amplitudes than in wild-type mice. Magnetically induced H-reflexes (MH-reflexes) which assess local circuitry in the lumbosacral area of the spinal cord were performed in rats. This response disappeared following an L3 contusion spinal cord injury, however, kainic acid (KA) injection at L3, known to selectively destroy interneurons, caused a shorter latency and an increase in the amplitude of the MH-reflex. M-SSEPs and MH-reflexes in rats and M-MEPs in mice compliment locomotor evaluation in assessing the functional integrity of the spinal cord under normal and pathological conditions in the non-sedated animal.


Subject(s)
Central Nervous System/physiology , Electric Stimulation , Evoked Potentials, Motor/physiology , Evoked Potentials, Somatosensory/physiology , H-Reflex/physiology , Magnetics , Animals , Consciousness , Female , Hindlimb/innervation , Mice , Rats , Rats, Sprague-Dawley
11.
Nat Neurosci ; 7(3): 261-8, 2004 Mar.
Article in English | MEDLINE | ID: mdl-14770187

ABSTRACT

Successful axon regeneration in the mammalian central nervous system (CNS) is at least partially compromised due to the inhibitors associated with myelin and glial scar. However, the intracellular signaling mechanisms underlying these inhibitory activities are largely unknown. Here we provide biochemical and functional evidence that conventional isoforms of protein kinase C (PKC) are key components in the signaling pathways that mediate the inhibitory activities of myelin components and chondroitin sulfate proteoglycans (CSPGs), the major class of inhibitors in the glial scar. Both the myelin inhibitors and CSPGs induce PKC activation. Blocking PKC activity pharmacologically and genetically attenuates the ability of CNS myelin and CSPGs to activate Rho and inhibit neurite outgrowth. Intrathecal infusion of a PKC inhibitor, Gö6976, into the site of dorsal hemisection promotes regeneration of dorsal column axons across and beyond the lesion site in adult rats. Thus, perturbing PKC activity could represent a therapeutic approach to stimulating axon regeneration after brain and spinal cord injuries.


Subject(s)
Chondroitin Sulfate Proteoglycans/metabolism , Growth Cones/metabolism , Myelin Proteins/metabolism , Nerve Regeneration/physiology , Protein Kinase C/metabolism , Repressor Proteins/metabolism , Animals , Cells, Cultured , Central Nervous System/cytology , Central Nervous System/growth & development , Central Nervous System/injuries , Chondroitin Sulfate Proteoglycans/pharmacology , Enzyme Inhibitors/pharmacology , Female , Growth Cones/drug effects , Growth Cones/ultrastructure , Myelin Proteins/pharmacology , Myelin-Associated Glycoprotein/metabolism , Myelin-Associated Glycoprotein/pharmacology , Nerve Regeneration/drug effects , Neural Pathways/cytology , Neural Pathways/growth & development , Neural Pathways/metabolism , Nogo Proteins , Protein Isoforms/antagonists & inhibitors , Protein Isoforms/genetics , Protein Isoforms/metabolism , Protein Kinase C/antagonists & inhibitors , Protein Kinase C/genetics , Rats , Rats, Sprague-Dawley , Recombinant Fusion Proteins/metabolism , Recombinant Fusion Proteins/pharmacology , Recovery of Function/drug effects , Recovery of Function/physiology , Repressor Proteins/pharmacology , Signal Transduction/drug effects , Signal Transduction/physiology , Spinal Cord/cytology , Spinal Cord/growth & development , Spinal Cord/metabolism , Treatment Outcome
12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 24(6): 752-5, 2004 Jun.
Article in Chinese | MEDLINE | ID: mdl-15766201

ABSTRACT

Quaternary ammonium salt has strong affinity with gold in cyanide solutions, but it is not readily stripped. Stripping with acidic thiourea solutions and air sparging shows promise. There are some reports on the process of thiourea stripping, but little about its mechanism. In this paper, the stripping mechanism of N263/sulphuric thiourea/alkaline cyanide gold solution is studied by EXAFS. According to the experiments, sulphuric acid, thiourea and gold-thiourea complex can be extracted by N263 as a neutral molecule, and the stripping process can be described as following: (1) Sulphuric acid and thiourea are extracted by N263; (2) In organic phase, gold-cyanide complex is converted to gold-thiourea complex, which exists as Au[SC(NH2)2]2HSO4, and CN- forms HCN with acid at the same time; (3) HCN is removed by air sparging, and Au[SC(NH2)2]2HSO4 is distributed between organic phase and liquor phase, most of which transfers to liquor phase and is stripped.


Subject(s)
Gold/isolation & purification , Quaternary Ammonium Compounds/chemistry , Reagent Strips/chemistry , Thiourea/chemistry , Amines , Cyanates/chemistry , Cyanides/chemistry , Electrochemistry , Environmental Monitoring , Gold/chemistry , Hydrogen-Ion Concentration , Metal Nanoparticles/chemistry , Nanotechnology , Pharmaceutical Solutions , Solutions/chemistry , Sulfuric Acids/chemistry
13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 23(2): 371-3, 2003 Apr.
Article in Chinese | MEDLINE | ID: mdl-12961899

ABSTRACT

The concentrations of gold in thiourea and sulfuric acid solutions using gold standard solutions in diluent royal water were determined by AAS. The linear range was 0.2-12 x 10(-6), and RSD < 5%. This method simplifies the analysis of gold in thiourea and sulfuric acid solution. Thiourea declines the absorbency of gold while sulfuric acid plays a contrary role. The determined value were satisfactor after being modified by the blank curve.


Subject(s)
Gold/analysis , Sulfuric Acids/chemistry , Thiourea/chemistry , Reproducibility of Results , Solutions , Spectrophotometry, Atomic/methods
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