Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 35
Filtrar
1.
J Insect Sci ; 23(2)2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36947034

RESUMO

Termites are believed to have evolved in a way that optimizes their foraging efficiency, which involves both searching for food and transporting it efficiently. Although the search efficiency has been well-studied through tunnel pattern analysis, transport efficiency has received limited attention due to the challenges of directly observing behavior that is highly influenced by environmental conditions. In this study, we introduce an individual-based model to simulate transport behavior and examine transport efficiency (E) by considering the tunnel surface irregularities and curvature, which are critical environmental factors. The model is characterized by four control variables: tunnel curvature (k1), termite stopping time at irregularity sites (k2), irregularity distribution (k3), and irregularity density (k4). The simulation results indicate that as k1 increases, E decreases, while k3 has little impact on E. The impact of k4 on E is decisive; when k4 ≤ 6, an increase in k4 results in increased traffic jam frequency and a faster reduction in E. However, when k4 > 6, the jamming frequency is not significantly affected, reducing the decrease in E. k2 strongly contributes to reducing E without significantly affecting the frequency. In the discussion section, we explore potential mechanisms that termites use to maintain transport efficiency in heterogeneous soils, and discuss how to improve the model to better reflect real-termite systems.


Assuntos
Isópteros , Animais , Comportamento Animal , Solo , Alimentos
2.
Proc Biol Sci ; 288(1954): 20210998, 2021 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-34255998

RESUMO

In collective animal motion, coordination is often achieved by feedback between leaders and followers. For stable coordination, a leader's signals and a follower's responses are hypothesized to be attuned to each other. However, their roles are difficult to disentangle in species with highly coordinated movements, hiding potential diversity of behavioural mechanisms for collective behaviour. Here, we show that two Coptotermes termite species achieve a similar level of coordination via distinct sets of complementary leader-follower interactions. Even though C. gestroi females produce less pheromone than C. formosanus, tandem runs of both species were stable. Heterospecific pairs with C. gestroi males were also stable, but not those with C. formosanus males. We attributed this to the males' adaptation to the conspecific females; C. gestroi males have a unique capacity to follow females with small amounts of pheromone, while C. formosanus males reject C. gestroi females as unsuitable but are competitive over females with large amounts of pheromone. An information-theoretic analysis supported this conclusion by detecting information flow from female to male only in stable tandems. Our study highlights cryptic interspecific variation in movement coordination, a source of novelty for the evolution of social interactions.


Assuntos
Isópteros , Animais , Feminino , Masculino , Feromônios
3.
Front Zool ; 18(1): 61, 2021 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-34903250

RESUMO

BACKGROUND: Foraging in group living animals such as social insects, is collectively performed by individuals. However, our understanding on foraging behavior of subterranean termites is extremely limited, as the process of foraging in the field is mostly concealed. Because of this limitation, foraging behaviors of subterranean termites were indirectly investigated in the laboratory through tunnel geometry analysis and observations on tunneling behaviors. In this study, we tracked subsets of foraging workers from juvenile colonies of Coptotermes formosanus (2-yr-old) to describe general foraging behavioral sequences and to find how foraging workers allocate time between the foraging site (food acquisition or processing) and non-foraging site (food transportation). RESULTS: Once workers entered into the foraging site, they spent, on average, a significantly longer time at the foraging site than the non-foraging site. Our clustering analysis revealed two different types of foraging workers in the subterranean termite based on the duration of time they spent at the foraging site and their foraging frequency. After entering the foraging site, some workers (cluster 1) immediately initiated masticating wood fragments, which they transferred as food boluses to recipient workers at the foraging site. Conversely, the recipient workers (cluster 2) moved around after entering the foraging site and received food from donating workers. CONCLUSIONS: This study provides evidence of task specialization within foraging cohorts in subterranean termites.

4.
J Nat Prod ; 83(2): 223-230, 2020 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-32031796

RESUMO

Cimicifuga dahurica has traditionally been used as an antipyretic, analgesic, and anti-inflammatory agent and as a treatment for uterine and anal prolapse. This study has investigated the potential beneficial effects of this medicinal plant and its components on Alzheimer's disease (AD) with a focus on amyloid beta (Aß) production and scopolamine-induced memory impairment in mice. An ethanol extract from C. dahurica roots decreased Aß production in APP-CHO cells [Chinese hamster ovarian (CHO) cells stably expressing amyloid precursor protein (APP)], as determined by an enzyme-linked immunosorbent assay and Western blot analysis. Then, the compounds isolated from C. dahurica were tested for their antiamyloidogenic activities. Four compounds (1-4) efficiently interrupted Aß generation by suppressing the level of ß-secretase in APP-CHO cells. Moreover, the in vivo experimental results demonstrated that compound 4 improved the cognitive performances of mice with scopolamine-induced disruption on behavioral tests and the expression of memory-related proteins. Taken together, these results suggest that C. dahurica and its constituents are potential agents for preventing or alleviating the symptoms of AD.


Assuntos
Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/farmacologia , Precursor de Proteína beta-Amiloide/farmacologia , Plantas Medicinais/química , Escopolamina/farmacologia , Doença de Alzheimer/dietoterapia , Doença de Alzheimer/metabolismo , Secretases da Proteína Precursora do Amiloide/metabolismo , Secretases da Proteína Precursora do Amiloide/farmacologia , Peptídeos beta-Amiloides/química , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Células CHO , Cimicifuga , Cricetinae , Cricetulus , Camundongos , Estrutura Molecular , Plantas Medicinais/metabolismo , Escopolamina/metabolismo
5.
J Phys Ther Sci ; 29(7): 1276-1280, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28744064

RESUMO

[Purpose] The aim of this study was to determine the effects of central and unilateral posteroanterior (PA) mobilization on cervical lordosis, muscle stiffness and range of motion in a patient with ankylosing spondylitis (AS). [Subject and Methods] The subject of this case study was diagnosed with AS in 1997. At baseline, variance was measured without any intervention during the first 3 days (2016.6.13-2016.6.15). Cervical PA mobilization was applied to each segment from C2-C7 from the 4th to the 11th day for 8 days. Intervention was not performed from the 12th to the 15th days for 4 days. Variances were measured a final time without intervention on the 16th day (2016.6.28). [Results] Cervical lordosis was seen to have increased. Muscle stiffness was significantly decreased after intervention and the effect of treatment lasted for five days without any additional intervention. The cervical flexion and extension angles were increased. However these increases were not statistically significant. Both the lateral flexion and left rotation angle were significantly increased and the effects of treatment lasted for five days without any additional intervention. [Conclusion] These results suggest that central and unilateral PA mobilization is effective in increasing cervical lordosis and range of motion, and decreasing muscle stiffness in patients with AS.

6.
J Phys Ther Sci ; 28(3): 967-70, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27134394

RESUMO

[Purpose] The purpose of this study was to investigate the immediate effect of proprioceptive neuromuscular facilitation on muscle tone and muscle stiffness in stroke patients. [ Subjects and Methods] The subjects consisted of 15 patients with chronic stroke (stroke group) and 15 healthy persons (healthy group). We measured the effects of proprioceptive neuromuscular facilitation intervention on the lower extremity using a muscle tone measurement device; this detected changes in muscle tone and stiffness in the lower extremity muscles. [Results] Measurements taken before the intervention showed that, on average, the lower extremity muscles of the stroke group showed abnormally increased muscle tone and stiffness compared to the lower extremity muscles of the healthy group. After the intervention, the average muscle tone and stiffness in the lower extremity muscles of the stroke group decreased, but this change was insignificant, and the differences between the two groups were also insignificant. [Conclusion] Based on the findings of this study, we recommend proprioceptive neuromuscular facilitation treatment of both affected and non-affected sides to decrease the abnormally increased muscle tone and stiffness in the lower extremity muscles of chronic stroke patients.

7.
J Phys Ther Sci ; 28(2): 596-601, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27065550

RESUMO

[Purpose] The purpose of this study was to assess the effect of eye movements and proprioceptive neuromuscular facilitation (PNF) on patients with neglect syndrome. [Subjects and Methods] The subjects were randomly allocated to 2 groups: the eye movements (EM) group; and the PNF with eye movements (PEM) group. The program was conducted five times each week for 6 weeks. Balance (both static and dynamic) and head alignment (craniovertebral angle and cranial rotation angle) were measured before and after testing. [Results] In measurements of static balance, the EM group showed significant improvement in sway length and sway area when examined in the eyes-open condition, but not when examined in the eyes-closed condition. The PEM group showed significant improvement when examined under both conditions. In the assessment of dynamic balance, both groups showed significant improvement in measurements of sway areas. With respect to head alignment, there were no significant differences pre- and post-testing in either the craniovertebral angle or the cranial rotation angle in the EM group, but the PEM group showed significant differences in both measurements. [Conclusion] These results suggest that in stroke patients with neglect syndrome, PNF with eye movements, rather than eye movements alone, has a greater positive effect on balance and head alignment.

8.
BMC Vet Res ; 11: 269, 2015 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-26497220

RESUMO

BACKGROUND: Animal behavioral responses have been recently established as a suitable tool for detecting contaminants in the environment for risk assessment in situ. In this study, we observed movement behavior of zebrafish (Danio rerio) before and after infection with Edwardsiella tarda CK41 for 3 days until death. METHODS: Infection status of zebrafish was confirmed through PCR and colonization assay as time progressed and lesion development in the tails of zebrafish was also examined. Movement behaviors in response to bacterial infection were patterned by self-organizing map (SOM) based on movement parameters, including speed (mm/s), acceleration (mm/s (2) ), stop duration (t), stop number (n), locomotory rate (mm/s), turning rate (rad/s), and meander (rad/mm). RESULTS: According to SOM result, clusters were identified firstly according to time and secondly according to infection. Two movement patterns were observed in the early period of infection: one group with minimum turning rate and meander (i.e., stiff movement) and the other group with maximum strop number. Late infection was characterized by long stop duration. CONCLUSION: SOM was suitable for extracting complex behavioral data and thus can serve as a referencing system for diagnosing disease development in order to reveal the mechanism of the infection process.


Assuntos
Comportamento Animal , Edwardsiella tarda , Infecções por Enterobacteriaceae/veterinária , Doenças dos Peixes/microbiologia , Peixe-Zebra , Animais , Infecções por Enterobacteriaceae/complicações , Infecções por Enterobacteriaceae/microbiologia , Doenças dos Peixes/etiologia , Atividade Motora
9.
J Phys Ther Sci ; 27(12): 3887-9, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26834374

RESUMO

[Purpose] The aim of the present study is to examine the effects of silver spike point therapy on elderly persons' chronic constipation. [Subjects and Methods] The subjects of the present study were 30 elderly chronic-constipation sufferers who resided in a nursing home and had other physical conditions that necessitated wheelchair ambulation. There were three test groups in the present study: an silver spike point group, an acupuncture group, and a control group; 10 subjects were assigned to each group. The silver spike point group and the acupuncture group received their respective interventions, which were applied to both sides of the Tiensu for 20 minutes per day, five days per week, over a four week period. Weekly bowel movement frequency was recorded, and the Constipation Assessment Scale and Bowel Function Assessment Form were used as data-gathering instruments. [Results] Following treatment, the silver spike point and acupuncture groups showed significant improvement, based on the Constipation Assessment Scale and the Bowel Function Assessment Form, compared with the control group. [Conclusion] Based on the above results, silver spike point therapy can be administered to alleviate chronic constipation in elderly nursing home residents who cannot walk independently due to declining physical functions.

10.
J Phys Ther Sci ; 27(1): 109-13, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25642050

RESUMO

[Purpose] The present study attempted to identify the effect of olfactory stimulation on the balance ability of stroke patients. [Subjects] Thirty-three (33 males) stroke patients participated in the study. The stroke patients were divided into three groups: a black pepper oil (BPO) group (n=11), lavender oil (LVO) group (n=11), and distilled water (DW) group (n=11). [Methods] Two sessions (control trial/stimulus trial) of Romberg's test (eyes open 1 min/eyes closed 1 min) were conducted on a force platform to measure the data for the COP (center of pressure). Olfactory stimulation was provided at as a stimulus. [Results] With the eyes open, a statistically significant difference was found in average anterior posterior displacement (Ymean) and average medial lateral displacement (Xmean) among the three groups when comparing the groups before and after stimulation. The comparison between the eyes open and eyes closed conditions in each group showed a significant difference in the area of the 95% confidence ellipse (area) and Xmean of the BPO group and in the area of the LVO group (area, Xmean). [Conclusion] The findings indicate that the interaction of brain areas activated by the olfactory stimulation exerts an influence on the balance ability of stroke patients.

11.
J Phys Ther Sci ; 26(1): 87-91, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24567682

RESUMO

[Purpose] The purpose of this study was to investigate thoracic coupled motions of 20 Korean young individuals. [Methods] Thoracic motion of twenty healthy male college students aged 23.2±3.1 was examined. The coupled motions of the thoracic regions T1-4, T4-8, T8-12 were measured using a three dimensional motion capture system. [Results] Coupled axial rotation in the same direction as lateral bending was observed in T1-T4 and T4-T8 in the neutral, flexed, and extended postures of the thoracic spine. In T8-T12, coupled axial rotation in the same direction as lateral bending were observed in the neutral and flexed postures, while coupled axial rotation in the opposite direction was observed in an extended posture. [Conclusion] The patterns of coupled motions in the thoracic spine demonstrated some variability between postures and regions in vivo. However, coupled motions in the same direction were predominantly lateral flexion or axial rotation in the three postures.

12.
Pest Manag Sci ; 80(3): 1137-1144, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37872844

RESUMO

BACKGROUND: To control subterranean termite pests, chitin synthesis inhibitor (CSI) baits have been widely applied. Despite CSI baits having low impacts on the environment, they require a lengthy time period to eliminate colonies. 20-hydroxyecdysone (20E) was proposed to speed up the baiting process as it showed faster mortality than CSI baits. However, the efficacy of 20E has previously not been tested at the colony level prior to applying in the field. RESULTS: We compared the effect of 20E, 20E + noviflumuron, noviflumuron and untreated control using colonies of Coptotermes formosanus. Our result revealed that both 20E and 20E + noviflumuron did not accelerate colony elimination and termite activity remained relatively stable during the observation periods. To determine the limited effects of 20E, we further investigated feeding duration and consumption amount of 20E with different concentrations (control, 100 and 1000 ppm) for 10 days. Termites ceased feeding after 1 day in 100 and 1000 ppm treatment and 100% mortality was observed within 10 days in 1000 ppm 20E, while mortality in the 100 ppm 20E treated group was much lower than that in the 1000 ppm group. Furthermore, no termites molted in the control and termites died from hyperecdysonism in 1000 ppm 20E treatment, whereas about 20% of termites molted in 100 ppm 20E. CONCLUSION: This study demonstrated that 20E may not be suitable as a sole active ingredient to accelerate elimination of a subterranean termite colony, while CSI baits and lower concentrations of 20E may reduce the lengthy time period in colony elimination. © 2023 Society of Chemical Industry.


Assuntos
Benzamidas , Fluorocarbonos , Inseticidas , Isópteros , Animais , Ecdisterona , Controle de Insetos , Hidrocarbonetos Fluorados
13.
Mol Neurobiol ; 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38801629

RESUMO

Dementia is a syndrome exhibiting progressive impairments on cognition and behavior beyond the normal course of aging, and Alzheimer's disease (AD) is one of the neurodegenerative diseases known to cause dementia. We investigated the effect of KGC07EH, the 30% ethanol extract of Euonymus hamiltonianus, against amyloid-ß (Aß) production and cognitive dysfunction in dementia models. KGC07EH was treated on Hela cells expressing the Swedish mutant form of amyloid precursor protein (APP), and the AD triple transgenic (3× TG) mice were given KGC07EH orally during 11-14 months of age (100 and 300 mg/kg/day). SH-SY5Y cell line was used to test KGC07EH on scopolamine-induced elevation of acetylcholinesterase (AChE) activity. ICR mice were intraperitoneally injected with scopolamine, and KGC07EH was administered orally (50, 100, and 200 mg/kg/day) for 4 weeks. KGC07EH treatment decreased Aß, sAPPß-sw, and sAPPß-wt levels and APP protein expressions while sAPPα was increased in Swedish mutant-transfected HeLa cells. KGC07EH treatment also significantly reduced the accumulation of Aß plaques and tau tangles in the brain of 3× TG mice as well as improving the cognitive function. In SH-SY5Y cells cultured with scopolamine, KGC07EH dose-dependently attenuated the increase of AChE activity. KGC07EH also improved scopolamine-induced learning and memory impairment in scopolamine-injected mice, and in their cerebral cortex and hippocampus, the expression levels of p-ERK, p-CREB, p-Akt, and BDNF were attenuated. KGC07EH inhibits APP processing and Aß production both in vitro and in vivo, while enhancing acetylcholine signaling and cognitive dysfunction which are the major symptoms of dementia.

14.
J Phys Ther Sci ; 25(9): 1177-9, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24259940

RESUMO

[Purpose] The purpose of this study was to determine the effects of resistance exercise strengthening the hip flexor and extensor muscles on functional gait of stroke patients. [Subjects and Methods] Twenty patients were randomized into two groups. Both groups performed conventional physical therapy for six weeks. The experimental group also performed isokinetic eccentric resistance exercises for the hip flexor and extensor muscles. The hip muscle strength, stair up and down time, TUG time(timed up and go test), and 10 m gait velocity were measured at the baseline, and after 3 weeks, and 6 weeks of treatment. [Results] The experimental showed significant improvements compared to the baseline in hip muscle strength, stair up and down time, TUG time and 10 m gait velocity after 3 and 6 weeks of treatment. After 3 and 6 weeks of treatment, there were gains in hip muscle strength and 10 m gait velocity. The control group showed no significant increase in hip muscle strength, stair up and down time, TUG time or 10 m gait velocity. [Conclusion] We consider that conventional physical therapy contributes to the improvement of functional gait of stroke patients. However, it is more desirable to perform isokinetic eccentric resistance exercises for hip flexor and extensor muscles combined with conventional physical therapy for the improvement of hip muscle strength, stair up and down time, TUG time and 10 m gait velocity.

15.
Pest Manag Sci ; 79(10): 3999-4003, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37271933

RESUMO

BACKGROUND: Stake surveys and in-ground monitoring stations have been widely used to study field populations of many subterranean termite species, but thus far they have never been intercepted by the invasive Asian subterranean termite, Coptotermes gestroi (Wasmann), in southeastern Florida. To investigate the reasons for the inability of C. gestroi to intercept these in-ground monitoring devices, we compared its tunnel geometry with that of the Formosan subterranean termite, Coptotermes formosanus Shiraki. Two-year-old incipient colonies of both species confined in simulated structural infestations were connected to planar arenas containing four wooden discs. RESULTS: Coptotermes formosanus colonies constructed more abundant and more complex tunnel networks and intercepted more wooden discs than C. gestroi. C. formosanus propagated shorter primary tunnels and longer secondary tunnels with more branching frequency than C. gestroi, and probably adopted an area searching strategy to search for food in an area before moving on to other areas. In comparison, C. gestroi used a distance searching strategy by constructing linear and long primary tunnels to search for food at distance. CONCLUSIONS: Because tunnels of C. gestroi were less abundant and they tend to travel straight for some distance, they may have bypassed survey stakes or in-ground monitoring stations that are sparsely distributed in soil. The tunnel geometry of C. gestroi may explain why none of these in-ground monitoring devices has been intercepted by this species in southeastern Florida. © 2023 Society of Chemical Industry.


Assuntos
Baratas , Isópteros , Animais , Florida
16.
J Econ Entomol ; 116(2): 538-545, 2023 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-36749607

RESUMO

Coptotermes formosanus Shiraki and C. gestroi (Wasmann) are economically important structural pests in urban areas. Due to anthropogenic activity, both species have been introduced into the United States, with their respective invasive ranges now overlapping in Florida, and the two species have the capability to hybridize. The potential for structural damage from subterranean termite colonies primarily depends on colony size. However, long-term colony growth and wood consumption capabilities of hybrid Coptotermes colonies remain to be investigated, to determine the potential pest status of field-established hybrid colonies. In this study, we investigated long-term colony development over four years to determine if aging hybrid colonies display vigor in terms of colony growth. In addition, we compared wood consumption rate of hybrid colonies to compare their potential impact as structural pests with the two parental species. In aging colonies (four-year-old), both hybrid mating types displayed a colony growth equivalent to C. formosanus. However, the wood consumption rates of four-year-old colonies of the two parental Coptotermes species and their hybrids were similar, indicating equal damaging potential. We also found multiple secondary reproductives in hybrid colonies, even in the presence of primary reproductives, which may favor their potential establishment and spread. Although hybrid colonies or hybrid alates have yet to be detected in the field, our results suggest that such hybrid colonies would be an additional termite threat in the future if they were established in the field.


Assuntos
Isópteros , Animais , Espécies Introduzidas , Madeira , Florida , Reprodução
17.
J Econ Entomol ; 116(6): 2027-2034, 2023 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-37804537

RESUMO

Reticulitermes speratus (Kolbe) is economically important pest in East Asia including Korea, Japan, and China where they infest wooden structures in urban areas. Previously, it has been reported that R. speratus consists of 5 subspecies, R. speratus kyushuensis Morimoto, R. speratus speratus Kolbe, R. speratus leptolabralis Morimoto, R. speratus okinawanus Morimoto, R. speratus yaeyamanus Morimoto, while only R. speratus kyushuensis was recorded in Korea in the past. However, it remains elusive if different subspecies of R. speratus other than R. speratus kyushuensis are present in Korea. In this study, we report the first record of R. speratus speratus from Korea, which was verified using soldier morphology and molecular characteristics obtained from a mitochondrial gene. R. speratus speratus Kolbe, 1885 (Blattodea: Rhinotermitidae) are found in several provinces, mainly southern regions in Korea, whereas R. speratus kyushuensis are distributed throughout the country. Our morphological comparison showed that R. speratus speratus can be distinguishable from R. speratus kyushuensis by the ratio of the posterior postmentum width to length. In the molecular comparison, R. speratus speratus revealed genetic differences of 3.06% (range 2.60-4.10%) from R. speratus kyushuensis using cytochrome oxidase subunit II gene sequences.


Assuntos
Baratas , Isópteros , Animais , Japão , China , República da Coreia , Isópteros/genética
18.
Environ Entomol ; 52(2): 254-258, 2023 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-36773009

RESUMO

Wood-feeding termites have a nitrogen-poor diet and have therefore evolved nitrogen conservation strategies. However, termite workers molt periodically, and throughout the lifetime of a colony, millions of exuviae, a nitrogen-rich resource, are produced by the colony. In Coptotermes Wasmann, workers foraging at remote feeding sites must return to the central part of the nest to molt, where the queen, king, eggs, and larvae are located. It was hypothesized that this molting-site fidelity is an efficient way to recycle nitrogen for reproduction and colony growth, as nestmates involved in exuviae consumption can directly transfer such resources to individuals engaged in reproduction (the queen) or growth (larvae). This study investigates whether incipient colonies of C. gestroi (Wasmann) can gain additional biomass when they are fed supplementary exuviae. Incipient colonies were reared in nitrogen-poor or nitrogen-rich conditions, and 0, 1, 5, or 10 exuviae were added to 3-month-old colonies. After 6.5 months, colonies reared in nitrogen-poor environments gained significantly more biomass when exuviae were added than colonies with no added exuviae. However, the addition of exuviae had no effect on colony growth for colonies reared in nitrogen-rich environments. In a second experiment, queens from colonies in which exuviae were effectively removed laid fewer eggs than queens from colonies in which exuviae were not removed. Therefore, consumption of exuviae from molting individuals by nestmates is an important part of the nitrogen recycling strategy in Coptotermes colonies, as it facilitates queen oviposition and colony growth, especially when such colonies have limited access to nitrogen-rich soils.


Assuntos
Baratas , Isópteros , Feminino , Animais , Oviposição , Reprodução , Larva
19.
ACS Omega ; 8(46): 43873-43882, 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-38027354

RESUMO

Agarperoxinols A and B (1-2), two naturally occurring humulene-type sesquiterpenoids with an unprecedented tricyclic 6/6/7 ring, were discovered from the agarwood of Aquilaria malaccensis. Their structures were unambiguously determined by various spectroscopic data, experimental ECD calculations, and single-crystal X-ray diffraction analysis. Agarperoxinol B showed significant and dose-dependent neuroinflammatory inhibitory effects on various proinflammatory mediators, including NO, TNF-α, IL-6, and IL-1ß, and suppressed iNOS and COX-2 enzymes in LPS-activated microglial cells. A mechanistic study demonstrated that agarperoxinol B remarkably inhibited the phosphorylation of the Akt and JNK signaling pathways. Agarperoxinol B also significantly reduced the expression of the microglial markers Iba-1, COX-2, and TNF-α in the mouse cerebral cortex. Our findings introduce a bioactive compound from natural products that decreases proinflammatory factor production and has application for the treatment of neurodegenerative diseases.

20.
Biomol Ther (Seoul) ; 30(5): 409-417, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35611585

RESUMO

Parkinson's disease (PD) is the second most common neurodegenerative disease worldwide, and accumulating evidence indicates that mitochondrial dysfunction is associated with progressive deterioration in PD patients. Previous studies have shown that sinapic acid has a neuroprotective effect, but its mechanisms of action remain unclear. The neuroprotective effect of sinapic acid was assayed in a PD mouse model generated by the neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) as well as in SH-SY5Y cells. Target protein expression was detected by western blotting. Sinapic acid treatment attenuated the behavioral defects and loss of dopaminergic neurons in the PD models. Sinapic acid also improved mitochondrial function in the PD models. MPTP treatment increased the abundance of mitochondrial fission proteins such as dynamin-related protein 1 (Drp1) and phospho-Drp1 Ser616. In addition, MPTP decreased the expression of the REV-ERB α protein. These changes were attenuated by sinapic acid treatment. We used the pharmacological REV-ERB α inhibitor SR8278 to confirmation of protective effect of sinapic acid. Treatment of SR8278 with sinapic acid reversed the protein expression of phospho-Drp1 Ser616 and REV-ERB α on MPTP-treated mice. Our findings demonstrated that sinapic acid protects against MPTP-induced PD and these effects might be related to the inhibiting abnormal mitochondrial fission through REV-ERB α.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA