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1.
Anim Cogn ; 26(2): 515-522, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36131103

RESUMO

Alarm signals and cues are crucial to animal survival and vary greatly across species. Eavesdropping on heterospecific alarm signals and cues can provide eavesdroppers with information about potential threats. In addition to acoustic alarm signals, evidence has accumulated that chemical alarm cues and disturbance cues can also play a role in alerting conspecifics to potential danger in adult anurans (frogs and toads). However, there is very little known about whether disturbance cues are exploited by heterospecifics. In the present study, we conducted a binary choice experiment and a prey chemical discrimination experiment, respectively, to test the responses of a sympatric anuran species (red webbed treefrogs, Rhacophorus rhodopus) and a sympatric predator species (Chinese green tree vipers, Trimeresurus stejnegeri) to disturbance odors emitted by serrate-legged small treefrogs (Kurixalus odontotarsus). In the binary choice experiment, we found that the presence of disturbance odors did not significantly trigger the avoidance behavior of R. rhodopus. In the prey chemical discrimination experiment, compared with odors from undisturbed K. odontotarsus (control odors) and odorless control, T. stejnegeri showed a significantly higher tongue-flick rate in response to disturbance odors. This result implies that disturbance odor cues of K. odontotarsus can be exploited by eavesdropping predators to detect prey. Our study provides partial evidence for heterospecific eavesdropping on disturbance cues and has an important implication for understanding heterospecific eavesdropping on chemical cues of adult anurans.


Assuntos
Sinais (Psicologia) , Odorantes , Animais , Anuros , Aprendizagem da Esquiva , Comportamento Predatório
2.
Front Zool ; 18(1): 28, 2021 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-34103057

RESUMO

BACKGROUND: Signal detection is crucial to survival and successful reproduction, and animals often modify behavioral decisions based on information they obtained from the social context. Undeniably, the decision-making in male-male competition and female choice of anurans (frogs and toads) depends heavily on acoustic signals. However, increasing empirical evidence suggests that additional or alternative types of cue (e.g., visual, chemical, and vibratory) can be used to detect, discriminate and locate conspecifics in many anuran species. Nevertheless, few studies have investigated whether conspecific odor cues affect male's calling behavior. In this study, we conducted an experiment to investigate whether and how different chemical cues (male odors, female odors, and stress odors) from conspecifics affect male's calling strategies in serrate-legged small treefrogs (Kurixalus odontotarsus), and whether the combined chemical and acoustic stimuli have additive effects on calling behavior or not. RESULTS: We found that compared with female odors, male K. odontotarsus reduced calling investment in response to male odors or stress odors, in the absence of rival's advertisement calls. When odor stimuli and advertisement calls were presented simultaneously, however, there were no differences in the vocal response of focal males among odor groups. CONCLUSIONS: These results provide evidence that male treefrogs switch calling investment according to different odor cues from conspecifics, and further demonstrate that calling behavior can be affected by chemical cues in anuran species. Our study highlights the potential role of airborne chemical cues in sex identification and contributes to increase our understanding of anuran communication.

3.
J Exp Biol ; 223(Pt 21)2020 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-32994202

RESUMO

There is increasing evidence that many anurans use multimodal cues to detect, discriminate and/or locate conspecifics and thus modify their behaviors. To date, however, most studies have focused on the roles of multimodal cues in female choice or male-male interactions. In the present study, we conducted an experiment to investigate whether male serrate-legged small treefrogs (Kurixalus odontotarsus) used visual or chemical cues to detect females and thus altered their competition strategies in different calling contexts. Three acoustic stimuli (advertisement calls, aggressive calls and compound calls) were broadcast in a randomized order after a spontaneous period to focal males in one of four treatment groups: combined visual and chemical cues of a female, only chemical cues, only visual cues and a control (with no females). We recorded the vocal responses of the focal males during each 3 min period. Our results demonstrate that males reduce the total number of calls in response to the presence of females, regardless of how they perceived the females. In response to advertisement calls and compound calls, males that perceived females through chemical cues produced relatively fewer advertisement calls but more aggressive calls. In addition, they produced relatively more aggressive calls during the playback of aggressive calls. Taken together, our study suggests that male Kodontotarsus adjust their competition strategies according to the visual or chemical cues of potential mates and highlights the important role of multisensory cues in male frogs' perception of females.


Assuntos
Anuros , Sinais (Psicologia) , Estimulação Acústica , Animais , Feminino , Masculino , Restrição Física , Vocalização Animal
4.
Yi Chuan ; 39(10): 939-946, 2017 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-29070489

RESUMO

Undergraduate students majoring in forestry generally reflect that genetics is one of the most difficult compul-sory courses, because the traditional teaching method is difficult to satisfy their needs. According to the theoretical charac-teristics of forestry and actual demands of the students, in the light of teaching and research experience in recent years, we adopted a series of typical genetic cases such as 'opening coffin to identify relatives', stem-throne of Lycium ruthenicum Murr, and magic powers in Harry Potter. Our practices revealed that the case teaching in genetics could train good personality traits, learning abilities and creativity of the students, stimulate their interests and initiatives in learning, and increase systematic learning.


Assuntos
Agricultura Florestal/educação , Genética/educação , Ensino , Humanos , Estudantes
5.
Cell Physiol Biochem ; 38(2): 619-34, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26849230

RESUMO

BACKGROUND/AIMS: As a major complication after thoracic radiotherapy, radiation-induced lung injury (RILI) has great impact on long term quality of life and could result in fatal respiratory insufficiency The present study was aimed to evaluate the effects of Myrtol standardized on RILI, and to investigate the underlying mechanism. METHODS: A mouse model of radiation-induced lung injury was generated by using thoracic irradiation with a single dose of 16Gy. Mice were orally administrated with Myrtol (25 mg/kg/day) for 4 weeks after irradiation, while prednisone (5 mg/kg/day) was used as a positive control. After then, the body weight and lung coefficient were calculated. The severity of fibrosis was evaluated by observing pulmonary sections after radiation and collagen content in lung tissues was calculated following the hydroxyproline (HYP) assay. Pathological changes were observed in all the groups by using HE staining and Masson staining. The serum levels of TGF-ß1, TNF-α, IL-1ß, IL-6, and PGE2 were also measured with an ELISA assay. Western blot assay was used to measure the impact of Myrtol on AKT and its downstream signaling pathway, including MMP-2 and MMP-9. The levels of Vimentin and α-SMA were evaluated with an immunofluorescence assay. RESULTS: Treatment with Myrtol standardized, but not prednisone, reduced lung coefficient and collagen deposition in lung tissues, while attenuated histological damages induced by irradiation. Myrtol standardized also reduced the production of MDA, while increased the level of SOD. It was also observed that Myrtol standardized inhibited TGF-ß1 and a series of pro-inflammatory cytokines including TNF-α, IL-1ß, IL-6, PGE2. While in prednisone group, even though the early pneumonitis was ameliorated, the collagen disposition remained unchanged in latter times. Immunofluorescence analysis also revealed elevation of vimentin and α-SMA in the alveoli after a single dose of 16Gy. CONCLUSION: The present results suggest Myrtol standardized as an effective agent for attenuating the lung injury induced by irradiation.


Assuntos
Lesão Pulmonar/tratamento farmacológico , Pulmão/efeitos dos fármacos , Pulmão/efeitos da radiação , Monoterpenos/uso terapêutico , Fibrose Pulmonar/tratamento farmacológico , Lesões Experimentais por Radiação/tratamento farmacológico , Protetores contra Radiação/uso terapêutico , Animais , Colágeno/análise , Citocinas/análise , Combinação de Medicamentos , Feminino , Pulmão/patologia , Lesão Pulmonar/patologia , Camundongos Endogâmicos C57BL , Monoterpenos/administração & dosagem , Fibrose Pulmonar/patologia , Lesões Experimentais por Radiação/patologia , Protetores contra Radiação/administração & dosagem , Superóxido Dismutase/análise
6.
Lab Invest ; 94(4): 362-70, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24468793

RESUMO

Radiotherapy is an effective treatment method for lung cancer, particularly when the disease is at an advanced stage. However, previous researchers have observed that the majority of patients with conventional radiation therapy develop distant metastases and succumb to the disease. Thus, identifying and understanding novel pathways for the development of new therapeutic targets is a major goal in research on pulmonary neoplasms. Recent studies suggest that epithelial-mesenchymal transition (EMT) is the most important contributor to cancer metastasis. Induction of this complex process requires endogenously produced microRNAs; specifically, downregulation of the miRNA-200c causes an induction of EMT. We recently identified the tank-binding kinase-1 (TBK1) as a downstream effector of the miR-200c-driven pathway, but the biological function of TBK1 in EMT remains unknown. In this study, we tested whether TBK1 has a role in radiation-induced EMT and identified associated potential mechanisms. Human alveolar type II epithelial carcinoma A549 cells were irradiated with (60)Co γ-rays. Western blotting revealed a time- and dose-dependent decrease in E-cadherin with a concomitant increase in vimentin after radiation, suggesting that the epithelial cells acquired a mesenchymal-like morphology. TBK1 siRNA significantly inhibited radiation-induced suppression of the epithelial marker E-cadherin and upregulation of the mesenchymal marker vimentin. The invasion and migratory potential of lung cancer cells upon radiation treatment was also reduced by TBK1 knockdown. Furthermore, radiation-induced EMT attenuated by TBK1 depletion was partially dependent on transcriptional factor ZEB1 expression. Finally, we found glycogen synthase kinase-3ß (GSK-3ß) is involved in regulation of radiation-induced EMT by TBK1. Thus, our findings reveal that TBK1 signaling regulates radiation-induced EMT by controlling GSK-3ß phosphorylation and ZEB1 expression. TBK1 may therefore constitute a useful target for treatment of radiotherapy-induced metastasis diseases.


Assuntos
Transição Epitelial-Mesenquimal , Quinase 3 da Glicogênio Sintase/metabolismo , Proteínas de Homeodomínio/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Radioterapia/efeitos adversos , Fatores de Transcrição/metabolismo , Linhagem Celular Tumoral , Raios gama/efeitos adversos , Glicogênio Sintase Quinase 3 beta , Humanos , NF-kappa B/metabolismo , Metástase Neoplásica , Neoplasias/etiologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Smad/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Homeobox 1 de Ligação a E-box em Dedo de Zinco
7.
Curr Zool ; 70(2): 253-261, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38726257

RESUMO

Vocal communication plays an important role in survival, reproduction, and animal social association. Birds and mammals produce complex vocal sequence to convey context-dependent information. Vocalizations are conspicuous features of the behavior of most anuran species (frogs and toads), and males usually alter their calling strategies according to ecological context to improve the attractiveness/competitiveness. However, very few studies have focused on the variation of vocal sequence in anurans. In the present study, we used both conventional method and network analysis to investigate the context-dependent vocal repertoire, vocal sequence, and call network structure in serrate-legged small treefrogs Kurixalus odontotarsus. We found that male K. odontotarsus modified their vocal sequence by switching to different call types and increasing repertoire size in the presence of a competitive rival. Specifically, compared with before and after the playback of advertisement calls, males emitted fewer advertisement calls, but more aggressive calls, encounter calls, and compound calls during the playback period. Network analysis revealed that the mean degree, mean closeness, and mean betweenness of the call networks significantly decreased during the playback period, which resulted in lower connectivity. In addition, the increased proportion of one-way motifs and average path length also indicated that the connectivity of the call network decreased in competitive context. However, the vocal sequence of K. odontotarsus did not display a clear small-world network structure, regardless of context. Our study presents a paradigm to apply network analysis to vocal sequence in anurans and has important implications for understanding the evolution and function of sequence patterns.

8.
J Geriatr Cardiol ; 21(4): 407-420, 2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38800545

RESUMO

OBJECTIVE: To evaluate the role of resting magnetocardiography in identifying severe coronary artery stenosis in patients with suspected coronary artery disease. METHODS: A total of 513 patients with angina symptoms were included and divided into two groups based on the extent of coronary artery disease determined by angiography: the non-severe coronary stenosis group (< 70% stenosis) and the severe coronary stenosis group (≥ 70% stenosis). The diagnostic model was constructed using magnetic field map (MFM) parameters, either individually or in combination with clinical indicators. The performance of the models was evaluated using receiver operating characteristic curves, accuracy, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV). Calibration plots and decision curve analysis were performed to investigate the clinical utility and performance of the models, respectively. RESULTS: In the severe coronary stenosis group, QR_MCTDd, S_MDp, and TT_MAC50 were significantly higher than those in the non-severe coronary stenosis group (10.46 ± 10.66 vs. 5.11 ± 6.07, P < 0.001; 7.2 ± 8.64 vs. 4.68 ± 6.95, P = 0.003; 0.32 ± 57.29 vs. 0.26 ± 57.29, P < 0.001). While, QR_MVamp, R_MA, and T_MA in the severe coronary stenosis group were lower (0.23 ± 0.16 vs. 0.28 ± 0.16, P < 0.001; 55.06 ± 48.68 vs. 59.24 ± 53.01, P < 0.001; 51.67 ± 39.32 vs. 60.45 ± 51.33, P < 0.001). Seven MFM parameters were integrated into the model, resulting in an area under the curve of 0.810 (95% CI: 0.765-0.855). The sensitivity, specificity, PPV, NPV, and accuracy were 71.7%, 80.4%, 93.3%, 42.8%, and 73.5%; respectively. The combined model exhibited an area under the curve of 0.845 (95% CI: 0.798-0.892). The sensitivity, specificity, PPV, NPV, and accuracy were 84.3%, 73.8%, 92.6%, 54.6%, and 82.1%; respectively. Calibration curves demonstrated excellent agreement between the nomogram prediction and actual observation. The decision curve analysis showed that the combined model provided greater net benefit compared to the magnetocardiography model. CONCLUSIONS: The novel quantitative MFM parameters, whether used individually or in combination with clinical indicators, have been shown to effectively predict the risk of severe coronary stenosis in patients presenting with angina-like symptoms. Magnetocardiography, an emerging non-invasive diagnostic tool, warrants further exploration for its potential in diagnosing coronary heart disease.

9.
Steroids ; 194: 109217, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36893827

RESUMO

The introduction of selenium-containing functional groups into steroids to study the biological activities of related derivatives is rarely reported in the literature. In the present study, using cholesterol as raw material, four cholesterol-3-selenocyanoates and eight B-norcholesterol selenocyanate derivatives were synthesized, respectively. The structures of the compounds were characterized by NMR and MS. The results of the in vitro antiproliferative activity test showed that the cholesterol-3-selenocyanoate derivatives did not exhibit obvious inhibitory on the tested tumor cell lines. However, the B-norcholesterol selenocyanate derivatives obtained by structural modification of cholesterol showed good inhibitory activity against the proliferation of tumor cell. Among them, compounds 9b-c, 9f and 12 showed similar inhibitory activity against tested tumor cells as positive control 2-methoxyestradiol, and better than Abiraterone. At the same time, these B-norcholesterol selenocyanate derivatives displayed a strong selective inhibitory against Sk-Ov-3 cell line. Except for compound 9g, the IC50 value of all B-norcholesterol selenocyanate compounds against Sk-Ov-3 cells was less than 10 µM, and compound 9d was 3.4 µM. In addition, Annexin V-FITC/PI double staining was used to analyze the cell death mechanism. The results showed that compound 9c could induce Sk-Ov-3 cells to enter programmed apoptosis in a dose-dependent manner. Furthermore, the in vivo antitumor experiments of compound 9f against zebrafish xenograft tumor showed that 9f displayed obvious inhibitory effect on the growth of human cervical cancer (HeLa) xenograft tumor in zebrafish. Our results provide new thinking for the study of such compounds as new antitumor drugs.


Assuntos
Antineoplásicos , Colesterol , Animais , Humanos , Antineoplásicos/química , Antineoplásicos/farmacologia , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Colesterol/química , Colesterol/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Estrutura Molecular , Relação Estrutura-Atividade , Peixe-Zebra/metabolismo , Cianatos/química , Cianatos/farmacologia , Compostos de Selênio/química , Compostos de Selênio/farmacologia
10.
J Neurosci ; 30(45): 15286-97, 2010 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-21068333

RESUMO

The elusiveness of neuropathic pain mechanisms is a major impediment in developing effective clinical treatments. Here we show that peripheral nerve injury decreased agrin expression in the ipsilateral spinal dorsal horn of rats displaying tactile allodynia. SCP1, an acetaminophen analog, suppressed allodynia and promoted agrin upregulation. Preemptive treatment with SCP1 also upregulated agrin, thereby preventing neuropathic pain development. Expression of 50 kDa agrin delivered by adeno-associated virus into the dorsal horn also suppressed allodynia and hyperalgesia. Allodynia suppression was a consequence of serine residue 896/897 phosphorylation of NMDA receptor NR1 subunits in the GABA interneurons of the dorsal horn. Agrin silencing by small interference RNA, administered with either AAV-Ag50 vector or SCP1, blocked allodynia suppression, agrin upregulation, and NR1 phosphorylation. In conclusion, 50 kDa agrin modulates neuropathic pain through NR1 phosphorylation in GABA neurons. This mechanism may open new approaches for treating not only neuropathic pain, but also epilepsy, tremors, and spasticity.


Assuntos
Agrina/metabolismo , Regulação para Baixo , Neuralgia/metabolismo , Neurônios/metabolismo , Nervo Isquiático/lesões , Agrina/genética , Análise de Variância , Animais , Western Blotting , Imuno-Histoquímica , Masculino , Neuralgia/etiologia , Fosforilação , Interferência de RNA , Ratos , Ratos Sprague-Dawley , Receptores de N-Metil-D-Aspartato/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Nervo Isquiático/metabolismo , Ácido gama-Aminobutírico/metabolismo
11.
J Biol Chem ; 285(50): 38951-60, 2010 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-20937840

RESUMO

Specific microRNAs (miRNAs), small non-coding RNAs that support homeostatic gene expression, are significantly altered in abundance in human neurological disorders. In monocytes, increased expression of an NF-κB-regulated miRNA-146a down-regulates expression of the interleukin-1 receptor-associated kinase-1 (IRAK-1), an essential component of Toll-like/IL-1 receptor signaling. Here we extend those observations to the hippocampus and neocortex of Alzheimer disease (AD) brain and to stressed human astroglial (HAG) cells in primary culture. In 66 control and AD samples we note a significant up-regulation of miRNA-146a coupled to down-regulation of IRAK-1 and a compensatory up-regulation of IRAK-2. Using miRNA-146a-, IRAK-1-, or IRAK-2 promoter-luciferase reporter constructs, we observe decreases in IRAK-1 and increases in miRNA-146a and IRAK-2 expression in interleukin-1ß (IL-1ß) and amyloid-ß-42 (Aß42) peptide-stressed HAG cells. NF-κB-mediated transcriptional control of human IRAK-2 was localized to between -119 and +12 bp of the immediate IRAK-2 promoter. The NF-κB inhibitors curcumin, pyrrolidine dithiocarbamate or CAY10512 abrogated both IRAK-2 and miRNA-146a expression, whereas IRAK-1 was up-regulated. Incubation of a protected antisense miRNA-146a was found to inhibit miRNA-146a and restore IRAK-1, whereas IRAK-2 remained unaffected. These data suggest a significantly independent regulation of IRAK-1 and IRAK-2 in AD and in IL-1ß+Aß42 peptide-stressed HAG cells and that an inducible, NF-κB-sensitive, miRNA-146a-mediated down-regulation of IRAK-1 coupled to an NF-κB-induced up-regulation of IRAK-2 expression drives an extensively sustained inflammatory response. The interactive signaling of NF-κB and miRNA-146a further illustrate interplay between inducible transcription factors and pro-inflammatory miRNAs that regulate brain IRAK expression. The combinatorial use of NF-κB inhibitors with miRNA-146a or antisense miRNA-146a may have potential as a bi-pronged therapeutic strategy directed against IRAK-2-driven pathogenic signaling.


Assuntos
Doença de Alzheimer/metabolismo , Astrócitos/metabolismo , Regulação Enzimológica da Expressão Gênica , Quinases Associadas a Receptores de Interleucina-1/biossíntese , MicroRNAs/metabolismo , NF-kappa B/metabolismo , Sequência de Bases , Encéfalo/metabolismo , Humanos , Inflamação , Dados de Sequência Molecular , Regiões Promotoras Genéticas , Transdução de Sinais , Receptores Toll-Like/metabolismo
12.
Am J Physiol Regul Integr Comp Physiol ; 300(2): R447-59, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21123757

RESUMO

During lactation, female small mammals frequently reduce their fat reserves to very low levels. The function of this reduction is unclear, as calculations suggest that the contribution of the withdrawn energy from fat to the total energy balance of lactation is trivial. An alternative hypothesis is that reducing fat leads to a reduction in circulating adipokines, such as leptin, that play a role in stimulating the hyperphagia of lactation. We investigated the role of circulating leptin in lactation by repleting leptin levels using miniosmotic pumps during the last 7 days of lactation in Brandt's voles (Lasiopodomys brandtii), a model small wild mammal we have extensively studied in the context of lactation energy demands. Repletion of leptin resulted in a dose-dependent reduction of body mass and food intake in lactating voles. Comparisons to nonreproducing individuals suggests that the reduced leptin in lactation, due to reduced fat stores, may account for ∼16% of the lactational hyperphagia. Reduced leptin in lactation may, in part, cause lactational hyperphagia via stimulatory effects on hypothalamic orexigenic neuropeptides (neuropeptide Y and agouti-related peptide) and inhibition of the anorexigenic neuropeptide (proopiomelanocortin). These effects were reversed by the experimental repletion of leptin. There was no significant effect of leptin treatment on daily energy expenditure, milk production or pup growth, but leptin repletion did result in a reversal of the suppression of uncoupling protein-1 levels in brown adipose tissue, indicating an additional role for reducing body fat and leptin during peak lacation.


Assuntos
Animais Lactentes/crescimento & desenvolvimento , Composição Corporal/efeitos dos fármacos , Ingestão de Alimentos/efeitos dos fármacos , Lactação/fisiologia , Leptina/farmacologia , Sistemas Neurossecretores/efeitos dos fármacos , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo Marrom/efeitos dos fármacos , Tecido Adiposo Marrom/metabolismo , Proteína Relacionada com Agouti/genética , Estruturas Animais/anatomia & histologia , Estruturas Animais/efeitos dos fármacos , Animais , Arvicolinae , Composição Corporal/fisiologia , Peso Corporal/efeitos dos fármacos , Ingestão de Alimentos/fisiologia , Ingestão de Energia/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Feminino , Expressão Gênica/efeitos dos fármacos , Hipotálamo/efeitos dos fármacos , Hipotálamo/metabolismo , Canais Iônicos/metabolismo , Lactação/efeitos dos fármacos , Leptina/administração & dosagem , Leptina/sangue , Leptina/farmacocinética , Fígado/anatomia & histologia , Fígado/efeitos dos fármacos , Proteínas Mitocondriais/metabolismo , Neuropeptídeo Y/genética , Sistemas Neurossecretores/fisiologia , Tamanho do Órgão/efeitos dos fármacos , Pró-Opiomelanocortina/genética , Proteína Desacopladora 1
13.
J Exp Biol ; 214(Pt 13): 2242-7, 2011 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-21653818

RESUMO

Both pregnancy and lactation are associated with hyperphagia, and circulating leptin levels are elevated during pregnancy but decreased during lactation in Brandt's voles, Lasiopodomys brandtii. Previous findings suggest that impaired leptin sensitivity contributes to hyperphagia during pregnancy. The present study aimed to examine whether the decreased circulating leptin level and/or hypothalamic leptin sensitivity contributed to the hyperphagia during lactation in Brandt's voles. The serum leptin level and mRNA expression of the long form of the leptin receptor (Ob-Rb), suppressor-of-cytokine-signalling-3 (SOCS-3), neuropeptide Y (NPY), agouti-related protein (AgRP), pro-opiomelanocortin (POMC) and cocaine- and amphetamine-regulated transcript (CART) in the hypothalamus were examined on dioestrous, day 5, day 17 of lactation and day 27 (1 week after weaning) in Brandt's voles. Compared with controls, hypothalamic Ob-Rb and SOCS-3 mRNA expression was not significantly changed during lactation. The serum leptin level was significantly lower in lactating females than in the non-reproductive group. Hypothalamic NPY and AgRP mRNA expression significantly increased whereas POMC mRNA expression was significantly decreased during lactation compared with controls. However, there were no significant changes in hypothalamic CART mRNA expression. Food intake was positively correlated with NPY and AgRP mRNA expression but negatively correlated with POMC mRNA expression during lactation. These data suggest that hyperphagia during lactation was associated with low leptin levels, but not impaired leptin sensitivity, and that the hypothalamic neuropeptides NPY, AgRP and POMC are involved in mediating the role of leptin in food intake regulation in lactating Brandt's voles.


Assuntos
Hiperfagia/metabolismo , Hipotálamo/metabolismo , Leptina/química , Neuropeptídeos/química , Animais , Arvicolinae , Composição Corporal , Primers do DNA/genética , Feminino , Lactação , Leptina/sangue , Neuropeptídeos/metabolismo , Gravidez , Prenhez , RNA Mensageiro/metabolismo , Proteínas Supressoras da Sinalização de Citocina/metabolismo
14.
Mycoses ; 54(5): e336-43, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21910755

RESUMO

Cryptococcus neoformans is a medically important fungus and can infect all the organs of the body. As vascular endothelial cell is an important target for C. neoformans to penetrate any organs, the differential protein expression of human umbilical vascular endothelial cell (HUVEC) after incubating with C. neoformans may be the key to penetration. The proteins of HUVECs incubated with C. neoformans and normal HUVECs were collected and purified. After two-dimensional electrophoresis, the differential protein expression was identified by matrix-assisted laser desorption/ionisation mass spectrometry. The mRNA levels of some proteins were measured by real-time PCR. Three proteins were found significantly overexpressed in HUVECs incubated with C. neoformans, and nine other proteins were downregulated. The mRNA levels of S100A10 and peroxiredoxin I fluctuated with the protein levels. These results suggested that the expressions of peroxiredoxin I and S100A10 were regulated during the process of invasion of HUVECs by C. neoformans. We hypothesise that these proteins take part in the modifications of HUVEC cytoskeleton and the tolerance to oxidative stress, which may affect the process of invasion by C. neoformans.


Assuntos
Cryptococcus neoformans/patogenicidade , Células Endoteliais/química , Células Endoteliais/microbiologia , Proteoma/análise , Anexina A2/biossíntese , Células Cultivadas , Técnicas de Cocultura , Eletroforese em Gel Bidimensional , Perfilação da Expressão Gênica , Humanos , Peroxirredoxinas/biossíntese , Proteínas S100/biossíntese , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
15.
Acta Pharmacol Sin ; 31(3): 307-12, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20140003

RESUMO

AIM: To investigate the efficacies of point-of-care test of heart-type fatty-acid binding protein (H-FABP) and its combinations with the conventional biomarkers in the diagnosis of early acute myocardial infarction (AMI). METHODS: 227 patients suspected of AMI were consecutively recruited in two centers. Biomarkers including H-FABP, myoglobin (MYO), creatine kinase-myocardial band (CK-MB) and cardiac troponin T (cTnT) were determined simultaneously at admission. AMI was defined according to the universal definition of myocardial infarction. Chi-Square test was adopted for the analysis. RESULTS: In patients presenting within 12 h of symptom onset, the sensitivity of H-FABP[93.0% (95% CI: 86.6%-96.9%)] was significantly higher than that of initial CK-MB [67.5% (95% CI: 58.1%-76.0%), P<0.0001], cTnT [69.3% (95%CI: 60.0%-77.6%), P<0.0001] and MYO [68.6% (95% CI: 54.1%-80.9%), P<0.05]. The negative predictive value of H-FABP [92.8% (95%CI: 86.3%-96.8%)] was significantly higher than that of initial CK-MB [74.7% (95% CI: 66.8%-81.5%), P<0.001] and cTnT [75.9% (95% CI: 68.1%-82.6%), P<0.001]. The sensitivity of H-FABP+cTnT combination [94.7% (95% CI: 88.9%-98.0%)] was significantly higher than that of admission cTnT [69.3% (95% CI: 60.0%-77.6%), P<0.0001], CK-MB+cTnT [75.4% (95% CI: 66.5%-83.0%), P<0.0001] and MYO+CK-MB+cTnT [74.5% (95% CI: 60.4%-85.7%), P<0.05]. The negative predictive value of H-FABP+cTnT [94.5% (95% CI: 88.4%-98.0%] was significantly higher than that of initial cTnT [75.9% (95% CI: 68.1%-82.6%), P<0.001] and CK-MB+cTnT [79.1% (95% CI: 71.2%-85.6%), P<0.001]. Subgroup analysis showed that the superiorities of both the sensitivities and the negative predictive values of H-FABP and H-FABP+cTnT combination occurred only in patients who presented within 6 h of the symptom onset. CONCLUSION: Point-of-care test of H-FABP can be used as a valuable biomarker to detect or exclude an early-stage AMI. Combining H-FABP and cTnT provides the best performance for early AMI diagnosis.


Assuntos
Proteínas de Ligação a Ácido Graxo , Infarto do Miocárdio/diagnóstico , Sistemas Automatizados de Assistência Junto ao Leito , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Troponina T
16.
Zhonghua Xin Xue Guan Bing Za Zhi ; 38(8): 702-5, 2010 Aug.
Artigo em Zh | MEDLINE | ID: mdl-21055136

RESUMO

OBJECTIVE: To explore the prevalence and associated factors of anxiety and depression symptoms in hospitalized Chinese patients with coronary artery disease (CAD). METHODS: From June 2007 to May 2009, 1083 hospitalized patients with confirmed coronary artery disease were recruited in this study. The ZUNG Self-rating Anxiety Scale (SAS) and the ZUNG Self-rating Depression Scale (SDS) were used for the psychological assessment. Economic status, living condition and the environment of both living and working places were evaluated by epidemiological questionnaires. RESULTS: The prevalence of pure anxiety, pure depression symptoms and the combination of anxiety and depression symptoms were 7.9%, 28.3% and 14.3% respectively. Incidence of anxiety and depression symptoms was significantly higher in female patients compared with in male patients (P = 0.003, 0.012 respectively) and in aged patients than in middle-aged patients (P = 0.001). The elderly, less than 9 years of education and poor sleep quality increased the risk of anxiety symptom with ORs of 1.63 (95%CI: 1.21 - 2.21), 1.54 (95%CI: 1.15 - 2.07) and 1.62 (95%CI: 1.34 - 1.96), respectively, while workplace noise, history of chronic disease and poor sleep quality increased the risk of depression symptom with ORs of 1.52 (95%CI: 1.18 - 1.98), 1.36 (95%CI: 1.06 - 1.75) and 1.27 (95%CI: 1.08 - 1.50), respectively. Female (OR = 1.91, 95%CI: 1.22-2.98), aged patient (OR = 1.84, 95%CI: 1.23 - 2.76), workplace noise (OR = 1.61, 95%CI: 1.07 - 2.42), history of chronic disease (OR = 1.84, 95%CI: 1.24 - 2.71) and poor sleep quality (OR = 1.73, 95%CI: 1.35 - 2.21) were significantly correlated with the combined incidence of anxiety and depression symptoms. CONCLUSION: Around half of the Chinese hospitalized CAD patients were complicated with various degrees of anxiety and/or depression symptoms. Female and aged patients were at higher risk for anxiety and depression symptoms. Sleep quality, workplace noise, years of education and history of chronic disease were independent risk factors for anxiety or depression symptoms.


Assuntos
Ansiedade/epidemiologia , Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/psicologia , Transtorno Depressivo/epidemiologia , Pacientes Internados/psicologia , Idoso , Feminino , Humanos , Masculino , Prevalência
17.
Am J Physiol Regul Integr Comp Physiol ; 297(5): R1293-301, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19726709

RESUMO

Brandt's voles Lasiopodomys brandtii exhibit large increases in nonshivering thermogenesis to cope with chronic cold exposure, resulting in compensatory hyperphagia and fat mobilization. These physiological events are accompanied by a remarkable reduction in serum leptin levels. However, the role of hypoleptinemia in cold adaptation in this species is still unknown. In the present study, we tested the hypothesis that hypoleptinemia contributes to increases in food intake and brown adipose tissue (BAT) thermogenesis by modifying hypothalamic neuropeptides in cold-exposed Brandt's voles. Adult male voles were transferred to 5 degrees C for 28 days. Accompanied by a decrease in serum leptin levels, hypothalamic agouti-related protein (AgRP) mRNA levels were significantly increased, but there were no changes in the long form of leptin receptor (Ob-Rb), suppressor of cytokine signaling 3 (SOCS3), neuropeptide Y (NPY) mRNA, proopiomelanocortin (POMC), and cocaine- and amphetamine-regulated peptide (CART) mRNA levels in the hypothalamus. When cold-exposed voles were returned to warm (23 degrees C) for 28 days, body mass, food intake, serum leptin, and AgRP mRNA were restored to control levels. Leptin administration in cold-exposed voles decreased food intake as well as hypothalamic AgRP mRNA levels. There were no significant effects of leptin administration on hypothalamic Ob-Rb, SOCS3, NPY, POMC, CART mRNA, and uncoupling protein 1 levels under cold conditions. These results suggest that hypoleptinemia partially contributes to cold-induced hyperphagia, which might involve the elevation of hypothalamic AgRP gene expression.


Assuntos
Adaptação Fisiológica/fisiologia , Arvicolinae/fisiologia , Temperatura Baixa , Leptina/sangue , Termogênese/fisiologia , Adaptação Fisiológica/efeitos dos fármacos , Tecido Adiposo Marrom/efeitos dos fármacos , Tecido Adiposo Marrom/fisiologia , Proteína Relacionada com Agouti/metabolismo , Animais , Ingestão de Alimentos/efeitos dos fármacos , Ingestão de Alimentos/fisiologia , Hipotálamo/metabolismo , Leptina/farmacologia , Masculino , Modelos Animais , Neuropeptídeo Y/metabolismo , Pró-Opiomelanocortina/metabolismo , RNA Mensageiro/metabolismo , Receptores para Leptina/metabolismo , Proteínas Supressoras da Sinalização de Citocina/metabolismo
18.
Steroids ; 74(1): 62-72, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18838084

RESUMO

The side chain of a compound plays an important role in its biological function. In our studies, we have found that hydroximinosteroid derivatives with different side chains and position of hydroximino on ring A and B displayed remarkable distinct cytotoxicities against a diversity of cancer cell types. Presence of an oxime group on ring B and a hydroxy on ring A or B resulted in a higher cytotoxicity than other structural motifs. In addition, a cholesterol-type side chain at position 17 was required for the biological activity. Our findings provide new evidence showing the relationship between the chemical structure and biological function. The information obtained from the studies may be useful for the design of novel chemotherapeutic drugs.


Assuntos
Citotoxinas/síntese química , Citotoxinas/farmacologia , Oximas/síntese química , Oximas/farmacologia , Esteroides/síntese química , Esteroides/farmacologia , Linhagem Celular Tumoral , Citotoxinas/química , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Oximas/química , Esteroides/química , Relação Estrutura-Atividade
19.
Ecol Evol ; 9(16): 9290-9297, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31463021

RESUMO

Social network analysis has been widely used to investigate the dynamics of social interactions and the evolution of social complexity across a range of taxa. Anuran species are highly dependent on vocal communication in mate choice; however, these species have rarely been the subject of social network analysis. The present study used social network analysis to investigate whether vocal network structures are consistent in Emei music frog (Babina daunchina) after the introduction of a simulated exotic rival of varying competitiveness into the social group. We broadcasted six categories of artificial calls (either highly sexually attractive calls produced from inside male nests or calls of low sexual attractiveness produced outside nests with three, five or seven notes, respectively) to simulate an intruder with different levels of competitiveness. We then constructed vocal networks for two time periods (before and after the disturbance) and quantified three network metrics (strength, closeness, and betweenness) that measure different aspects of individual-level position. We used the mean values of these network metrics to evaluate group-level changes in network structure. We found that the mean strength, mean closeness and mean betweenness were consistent between two time periods in all ponds, despite the fact that the positions of some individuals had changed markedly after disturbance. In addition, there was no significant interaction effect between period and numbers of notes on the three network metrics. These finding suggest that the structure of vocal networks in Emei music frogs remain stable at the group level after a conspecific disturbance, regardless of the intruder's competitiveness.

20.
Behav Processes ; 169: 103997, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31698032

RESUMO

Artificial light at night (ALAN) is a widespread anthropogenic stimulus that can significantly alter nocturnal animals' behavior, from migration to foraging to vocal communication. In the present study, we tested the hypothesis that the mate choice decisions of female serrate-legged small treefrogs (Kurixalus odontotarsus) were influenced by ambient light intensity. Standard two-speaker phonotaxis tests were conducted in a sound attenuating chamber. We set four light treatments (I-IV, from low to high) based on a range of light intensities from the maximum natural light at night (i.e., full moon) to that of the actual calling sites, which had artificial light. Contrary to our prediction, female frogs showed a preference for calls on the bright side in treatment I when they were exposed to identical stimuli. However, females preferred longer calls on the dim side to shorter calls on the bright side in this treatment. In addition, there were no significant effects of choice side, light treatment or their interaction on leave time or choice time. Our results suggest that females are more attracted to mates in bright light under natural nocturnal light conditions, but the preference for longer calls is not altered in serrate-legged small treefrogs.


Assuntos
Luz , Preferência de Acasalamento Animal/fisiologia , Animais , Anuros , Feminino
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