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1.
J Biol Chem ; 300(8): 107556, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39002683

RESUMO

Diversity, a hallmark of G protein-coupled receptor (GPCR) signaling, partly stems from alternative splicing of a single gene generating more than one isoform for a receptor. Additionally, receptor responses to ligands can be attenuated by desensitization upon prolonged or repeated ligand exposure. Both phenomena have been demonstrated and exemplified by the deuterostome tachykinin signaling system, although the role of phosphorylation in desensitization remains a subject of debate. Here, we describe the signaling system for tachykinin-related peptides (TKRPs) in a protostome, mollusk Aplysia. We cloned the Aplysia TKRP precursor, which encodes three TKRPs (apTKRP-1, apTKRP-2a, and apTKRP-2b) containing the FXGXR-amide motif. In situ hybridization and immunohistochemistry showed predominant expression of TKRP mRNA and peptide in the cerebral ganglia. TKRPs and their posttranslational modifications were observed in extracts of central nervous system ganglia using mass spectrometry. We identified two Aplysia TKRP receptors (apTKRPRs), named apTKRPR-A and apTKRPR-B. These receptors are two isoforms generated through alternative splicing of the same gene and differ only in their intracellular C termini. Structure-activity relationship analysis of apTKRP-2b revealed that both C-terminal amidation and conserved residues of the ligand are critical for receptor activation. C-terminal truncates and mutants of apTKRPRs suggested that there is a C-terminal phosphorylation-independent desensitization for both receptors. Moreover, apTKRPR-B also exhibits phosphorylation-dependent desensitization through the phosphorylation of C-terminal Ser/Thr residues. This comprehensive characterization of the Aplysia TKRP signaling system underscores the evolutionary conservation of the TKRP and TK signaling systems, while highlighting the intricacies of receptor regulation through alternative splicing and differential desensitization mechanisms.


Assuntos
Aplysia , Isoformas de Proteínas , Animais , Aplysia/metabolismo , Fosforilação , Isoformas de Proteínas/metabolismo , Isoformas de Proteínas/genética , Receptores de Taquicininas/metabolismo , Receptores de Taquicininas/genética , Taquicininas/metabolismo , Taquicininas/genética , Sequência de Aminoácidos , Transdução de Sinais , Processamento Alternativo , Humanos
2.
J Biol Chem ; 298(10): 102440, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36049520

RESUMO

The protostome leucokinin (LK) signaling system, including LK peptides and their G protein-coupled receptors, has been characterized in several species. Despite the progress, molecular mechanisms governing LK peptide-receptor interactions remain to be elucidated. Previously, we identified a precursor protein for Aplysia leucokinin-like peptides (ALKs) that contains the greatest number of amidated peptides among LK precursors in all species identified so far. Here, we identified the first ALK receptor from Aplysia, ALKR. We used cell-based IP1 activation assays to demonstrate that two ALK peptides with the most copies, ALK1 and ALK2, activated ALKR with high potencies. Other endogenous ALK-derived peptides bearing the FXXWX-amide motif also activated ALKR to various degrees. Our examination of cross-species activity of ALKs with the Anopheles LK receptor was consistent with a critical role for the FXXWX-amide motif in receptor activity. Furthermore, we showed, through alanine substitution of ALK1, the highly conserved phenylalanine (F), tryptophan (W), and C-terminal amidation were each essential for receptor activation. Finally, we used an artificial intelligence-based protein structure prediction server (Robetta) and Autodock Vina to predict the ligand-bound conformation of ALKR. Our model predicted several interactions (i.e., hydrophobic interactions, hydrogen bonds, and amide-pi stacking) between ALK peptides and ALKR, and several of our substitution and mutagenesis experiments were consistent with the predicted model. In conclusion, our results provide important information defining possible interactions between ALK peptides and their receptors. The workflow utilized here may be useful for studying other ligand-receptor interactions for a neuropeptide signaling system, particularly in protostomes.


Assuntos
Aplysia , Inteligência Artificial , Neuropeptídeos , Receptores de Neuropeptídeos , Animais , Amidas , Aplysia/genética , Aplysia/metabolismo , Ligantes , Mutagênese , Neuropeptídeos/química , Neuropeptídeos/genética , Conformação Proteica , Receptores de Neuropeptídeos/química , Receptores de Neuropeptídeos/genética
3.
Neoplasma ; 69(3): 657-669, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35293765

RESUMO

Colorectal cancer (CRC) is a common malignant tumor with high morbidity and mortality, and significant heterogeneity among patients. In this study, we aimed to explore the role and mechanism of CLK2 in CRC, a kinase that phosphorylates SR proteins involved in splicing. Based on the analysis from The Cancer Genome Atlas (TCGA) dataset and tissue microarray, we found that CLK2 was upregulated in CRC tissues and associated with a higher tumor stage and poorer overall survival. Consistent with the bioinformatics analysis, the functional experiments validated that CLK2 acted as a tumor-promoting factor in CRC progression. CLK2 knockdown suppressed aggressive cell proliferation, migration, and invasion in vitro, as well as restrained tumor growth in vivo. In terms of mechanism, we found that the Wnt/ß-catenin signaling pathway was responsible for the CLK2-induced CRC progression, based on the results of pathway enrichment analysis and subsequent experimental validation. Thus, our study, for the first time, identified the role of CLK2 in CRC development and provided a compelling biomarker for targeted therapy in CRC treatment.


Assuntos
Neoplasias Colorretais , Proteínas Serina-Treonina Quinases , Proteínas Tirosina Quinases , Via de Sinalização Wnt , Carcinogênese/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Centers for Disease Control and Prevention, U.S. , Neoplasias Colorretais/patologia , Regulação Neoplásica da Expressão Gênica , Humanos , Proteínas Serina-Treonina Quinases/genética , Proteínas Tirosina Quinases/genética , Estados Unidos , Via de Sinalização Wnt/genética , beta Catenina/metabolismo
4.
Am J Emerg Med ; 50: 661-669, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34879483

RESUMO

BACKGROUND: Recently, emerging evidence has suggested that atrial fibrillation (AF) has an epidemiological correlation with coronavirus disease 2019 (COVID-19). However, the clinical outcomes of AF in COVID-19 remain inconsistent and inconclusive. The aim of this study was to provide a comprehensive description of the impact of AF on the prognosis of patients with COVID-19 pneumonia. METHODS: Three electronic databases (PubMed, Embase, and Web of Science) were searched for eligible studies as of March 1, 2021. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were used to evaluate the associations between AF (preexisting and new-onset) and in-hospital mortality, post-discharge mortality, and ventilator use. RESULTS: A total of 36 individual studies were incorporated into our meta-analysis. The combined results revealed that preexisting AF was associated with increased in-hospital mortality (pooled OR: 2.07; 95% CI: 1.60-2.67; p < 0.001), post-discharge mortality (pooled OR: 2.69; 95% CI: 1.24-5.83; p < 0.05), and ventilator utilization (pooled OR: 4.53; 95% CI: 1.33-15.38; p < 0.05) in patients with COVID-19. In addition, our data demonstrated that new-onset AF during severe acute respiratory syndrome coronavirus 2 infection was significantly correlated with increased mortality (pooled OR: 2.38; 95% CI: 2.04-2.77; p < 0.001). CONCLUSIONS: The presence of AF is correlated with adverse outcomes in patients with COVID-19 pneumonia, which deserves increased attention and should be managed appropriately to prevent adverse outcomes.


Assuntos
Fibrilação Atrial/mortalidade , Fibrilação Atrial/virologia , COVID-19/complicações , COVID-19/mortalidade , Mortalidade Hospitalar , Humanos , Respiração Artificial , Taxa de Sobrevida
5.
Am J Emerg Med ; 42: 23-30, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33429188

RESUMO

BACKGROUND: The outcomes of new-onset atrial fibrillation (AF) during sepsis are inconsistent and inconclusive. This meta-analysis aims to provide a comprehensive description of the impact of new-onset AF on the prognosis of sepsis. METHODS: Three electronic databases (PubMed, Embase, and the Cochrane Library) were searched for relevant studies. Meta-analysis was performed using odds ratios (OR) and 95% confidence intervals (CI) as effect measures. RESULTS: A total of 225,841 patients from 13 individual studies were incorporated to the meta-analysis. The summary results revealed that new-onset AF during sepsis was associated with increased odds of in-hospital mortality (pooled OR: 2.09; 95% CI: 1.53-2.86; p < 001), post-discharge mortality (pooled OR: 2.44; 95% CI: 1.81-3.29; p < .001), and stroke (pooled OR:1.88; 95% CI: 1.13-3.14; p < .05). Results also indicated that the incidence of new-onset AF varied from 1.9% for mild sepsis to 46.0% for septic shock. Furthermore, compared to those without AF, people with new-onset AF had longer ICU and hospital stays, as well as a higher recurrence of AF. CONCLUSIONS: New-onset AF is frequently associated with adverse outcomes in patients with sepsis. This is a clinical issue that warrants more attention and should be managed appropriately to prevent poor prognosis.


Assuntos
Fibrilação Atrial/etiologia , Sepse/complicações , Fibrilação Atrial/mortalidade , Cuidados Críticos , Mortalidade Hospitalar , Humanos , Tempo de Internação , Prognóstico , Recidiva , Fatores de Risco , Sepse/mortalidade , Choque Séptico/complicações , Choque Séptico/mortalidade , Acidente Vascular Cerebral/etiologia
6.
Chin J Traumatol ; 24(3): 169-173, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33707100

RESUMO

PURPOSE: This study was designed to compare the clinical efficacy of "8" and "0" wire fixation systems combined with double-head cannulated compression screws or Kirschner wires for the treatment of transverse patellar fractures. METHODS: From September 2011 to September 2018, patients with closed transverse patellar fractures treated with a double-head compression screw or Kirschner wire were included and analyzed retrospectively. Patients with patellar fractures combined with distal femoral fractures, tibial plateau fracture or preoperative lower limb dysfunction were excluded. The patients treated with the "8" tension band wire fixation system and Kirschner wire were taken as Group A; those treated with the "0" fixation system and Kirschner wire were taken as Group B; those treated with the "8" fixation system and double-head cannulated compression screw were taken as group C; and those treated with the "0" fixation system and double-head cannulated compression screw were taken as group D. Six weeks and one year after the operation and every month from the third month after the operation until the fractures healed, an X-ray examination was performed to identify fracture healing. The time of fracture healing and postoperative complications of the four groups were compared. One year after the operation, knee function was evaluated by Bostman's score. RESULTS: During the study period, 168 patients with patellar fractures were treated by operations, and 88 patients were excluded because the fracture type did not meet the requirements or because there were combined fractures of the distal femur or tibial plateau. As a result, 80 patients were included in this study, 20 in each group. All the patients were followed up for an average period of 12.2 months. Compared with Group A, patients in Group D presented less postoperative discomfort in the prepatellar region, quicker fracture healing, less fixation failure and better postoperative knee function scores (all p < 0.05). The incidence of internal fixation failure in Group (B+D) was lower than that in Group (A+C) (p > 0.05). CONCLUSION: The "0" wire fixation system combined with a double-head cannulated compression screw seems to be more beneficial than the other three fixation systems for the treatment of transverse patellar fractures.


Assuntos
Fraturas Ósseas , Patela , Fios Ortopédicos , Fixação Interna de Fraturas , Fraturas Ósseas/diagnóstico por imagem , Fraturas Ósseas/cirurgia , Humanos , Patela/cirurgia , Estudos Retrospectivos , Resultado do Tratamento
7.
Bioorg Med Chem Lett ; 29(5): 749-754, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30630718

RESUMO

Signal molecules are stimulators of multiple quroum-sensing virulence and biofilm formation. Small molecule analogues have been suspected as a potent inhibitor in therapeutic strategy. Herein, we synthesized a series of small molecule compounds from the 2, 8-bit derivatives of quinoline by Suzuki coupling reaction. We found that these compounds have the biofilm inhibitory effect in normal condition instead of phosphate limitation state. Furthermore, lacZ reporter strain assay and rhamnolipids as well as pyocyanin experiments showed that these compounds did not affect las and pqs system but reduced the expression of rhl. All these results suggest that quinoline derivatives can be treated as potent inhibitors against biofilm and reduce virulence through the rhl system. This research will be useful in designing new quorum sensing inhibitors to attenuate the infection of bacteria.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Pseudomonas aeruginosa/efeitos dos fármacos , Quinolinas/farmacologia , Virulência/efeitos dos fármacos , Óperon Lac , Pseudomonas aeruginosa/patogenicidade , Quinolinas/química , Percepção de Quorum
8.
Phytomedicine ; 123: 155251, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38056151

RESUMO

BACKGROUND: Insomnia and depressive disorder are two common symptoms with a reciprocal causal relationship in clinical practice, which are usually manifested in comorbid form. Several medications have been widely used in the treatment of insomnia and depression, but most of these drugs show non-negligible side effects. Currently, many treatments are indicated for insomnia and depressive symptom, including Chinese herbal medicine such as Gastrodia elata Blume (G. elata), which has excellent sedative-hypnotic and antidepressant effects in clinical and animal studies. PURPOSE: To summarize the mechanisms of insomnia and depression and the structure-activity mechanism for G. elata to alleviate these symptoms, particularly by hypothalamic-pituitary-adrenal (HPA) axis and intestinal flora, aiming to discover new approaches for the treatment of insomnia and depression. METHODS: The following electronic databases were searched from the beginning to November 2023: PubMed, Web of Science, Google Scholar, Wanfang Database, and CNKI. The following keywords of G. elata were used truncated with other relevant topic terms, such as depression, insomnia, antidepressant, sedative-hypnotic, neuroprotection, application, safety, and toxicity. RESULTS: Natural compounds derived from G. elata could alleviate insomnia and depressive disorder, which is involved in monoamine neurotransmitters, inflammatory response, oxidative stress, and gut microbes, etc. Several clinical trials showed that G. elata-derived natural compounds that treat depression and insomnia have significant and safe therapeutic effects, but further well-designed clinical and toxicological studies are needed. CONCLUSION: G. elata exerts a critical role in treating depression and insomnia due to its multi-targeting properties and fewer side effects. However, more clinical and toxicological studies should be performed to further explore the sedative-hypnotic and antidepressant mechanisms of G. elata and provide more evidence and recommendations for its clinical application. Our review provides an overview of G. elata treating insomnia with depression for future research direction.


Assuntos
Gastrodia , Distúrbios do Início e da Manutenção do Sono , Animais , Extratos Vegetais/efeitos adversos , Distúrbios do Início e da Manutenção do Sono/tratamento farmacológico , Antidepressivos/farmacologia , Antidepressivos/uso terapêutico
9.
J Med Chem ; 66(21): 14735-14754, 2023 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-37874867

RESUMO

Pseudomonas aeruginosa (P. aeruginosa) is well-known to cause biofilm-associated drug resistance and infections that often lead to treatment failure. Herein, we reported a dual-acting antibiofilm strategy by inhibiting both the bacterial quorum sensing system and the iron uptake system. A series of coumarin derivatives were synthesized and evaluated, and compound 4t was identified as the most effective biofilm inhibitor (IC50 = 3.6 µM). Further mechanistic studies have confirmed that 4t not only inhibits the QS systems but also competes strongly with pyoverdine as an iron chelator, causing an iron deficiency in P. aeruginosa. Additionally, 4t significantly improved the synergistic antibacterial effects of ciprofloxacin and tobramycin by more than 200-1000-fold compared to the single-dose antibiotic treatments. Therefore, our study has shown that 4t is a potentially novel antibacterial synergist candidate to treat bacterial infections.


Assuntos
Pseudomonas aeruginosa , Percepção de Quorum , Cumarínicos/farmacologia , Antibacterianos/farmacologia , Biofilmes , Ferro/farmacologia , Homeostase , Fatores de Virulência , Proteínas de Bactérias
10.
Front Pharmacol ; 14: 1132066, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37021048

RESUMO

The vasopressin/oxytocin signaling system is present in both protostomes and deuterostomes and plays various physiological roles. Although there were reports for both vasopressin-like peptides and receptors in mollusc Lymnaea and Octopus, no precursor or receptors have been described in mollusc Aplysia. Here, through bioinformatics, molecular and cellular biology, we identified both the precursor and two receptors for Aplysia vasopressin-like peptide, which we named Aplysia vasotocin (apVT). The precursor provides evidence for the exact sequence of apVT, which is identical to conopressin G from cone snail venom, and contains 9 amino acids, with two cysteines at position 1 and 6, similar to nearly all vasopressin-like peptides. Through inositol monophosphate (IP1) accumulation assay, we demonstrated that two of the three putative receptors we cloned from Aplysia cDNA are true receptors for apVT. We named the two receptors as apVTR1 and apVTR2. We then determined the roles of post-translational modifications (PTMs) of apVT, i.e., the disulfide bond between two cysteines and the C-terminal amidation on receptor activity. Both the disulfide bond and amidation were critical for the activation of the two receptors. Cross-activity with conopressin S, annetocin from an annelid, and vertebrate oxytocin showed that although all three ligands can activate both receptors, the potency of these peptides differed depending on their residue variations from apVT. We, therefore, tested the roles of each residue through alanine substitution and found that each substitution could reduce the potency of the peptide analog, and substitution of the residues within the disulfide bond tended to have a larger impact on receptor activity than the substitution of those outside the bond. Moreover, the two receptors had different sensitivities to the PTMs and single residue substitutions. Thus, we have characterized the Aplysia vasotocin signaling system and showed how the PTMs and individual residues in the ligand contributed to receptor activity.

11.
Research (Wash D C) ; 6: 0060, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36930762

RESUMO

Locomotion in mollusc Aplysia is implemented by a pedal rolling wave, a type of axial locomotion. Well-studied examples of axial locomotion (pedal waves in Drosophila larvae and body waves in leech, lamprey, and fish) are generated in a segmented nervous system via activation of multiple coupled central pattern generators (CPGs). Pedal waves in molluscs, however, are generated by a single pedal ganglion, and it is unknown whether there are single or multiple CPGs that generate rhythmic activity and phase shifts between different body parts. During locomotion in intact Aplysia, bursting activity in the parapedal commissural nerve (PPCN) was found to occur during tail contraction. A cluster of 20 to 30 P1 root neurons (P1Ns) on the ventral surface of the pedal ganglion, active during the pedal wave, were identified. Computational cluster analysis revealed that there are 2 phases to the motor program: phase I (centered around 168°) and phase II (centered around 357°). PPCN activity occurs during phase II. The majority of P1Ns are motoneurons. Coactive P1Ns tend to be electrically coupled. Two classes of pedal interneurons (PIs) were characterized. Class 1 (PI1 and PI2) is active during phase I. Their axons make a loop within the pedal ganglion and contribute to locomotor pattern generation. They are electrically coupled to P1Ns that fire during phase I. Class 2 (PI3) is active during phase II and innervates the contralateral pedal ganglion. PI3 may contribute to bilateral coordination. Overall, our findings support the idea that Aplysia pedal waves are generated by a single CPG.

12.
ACS Chem Neurosci ; 14(13): 2425-2442, 2023 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-37339428

RESUMO

Neuropeptides with the C-terminal Wamide (Trp-NH2) are one of the last common ancestors of peptide families of eumetazoans and play various physiological roles. In this study, we sought to characterize the ancient Wamide peptides signaling systems in the marine mollusk Aplysia californica, i.e., APGWamide (APGWa) and myoinhibitory peptide (MIP)/Allatostatin B (AST-B) signaling systems. A common feature of protostome APGWa and MIP/AST-B peptides is the presence of a conserved Wamide motif in the C-terminus. Although orthologs of the APGWa and MIP signaling systems have been studied to various extents in annelids or other protostomes, no complete signaling systems have yet been characterized in mollusks. Here, through bioinformatics, molecular and cellular biology, we identified three receptors for APGWa, namely, APGWa-R1, APGWa-R2, and APGWa-R3. The EC50 values for APGWa-R1, APGWa-R2, and APGWa-R3 are 45, 2100, and 2600 nM, respectively. For the MIP signaling system, we predicted 13 forms of peptides, i.e., MIP1-13 that could be generated from the precursor identified in our study, with MIP5 (WKQMAVWa) having the largest number of copies (4 copies). Then, a complete MIP receptor (MIPR) was identified and the MIP1-13 peptides activated the MIPR in a dose-dependent manner, with EC50 values ranging from 40 to 3000 nM. Peptide analogs with alanine substitution experiments demonstrated that the Wamide motif at the C-terminus is necessary for receptor activity in both the APGWa and MIP systems. Moreover, cross-activity between the two signaling systems showed that MIP1, 4, 7, and 8 ligands could activate APGWa-R1 with a low potency (EC50 values: 2800-22,000 nM), which further supported that the APGWa and MIP signaling systems are somewhat related. In summary, our successful characterization of Aplysia APGWa and MIP signaling systems represents the first example in mollusks and provides an important basis for further functional studies in this and other protostome species. Moreover, this study may be useful for elucidating and clarifying the evolutionary relationship between the two Wamide signaling systems (i.e., APGWa and MIP systems) and their other extended neuropeptide signaling systems.


Assuntos
Aplysia , Neuropeptídeos , Animais , Sequência de Aminoácidos , Moluscos , Peptídeos
13.
J Econ Entomol ; 105(3): 854-9, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22812121

RESUMO

The effects of intercropping wheat, Triticum aestivum L., with mung bean, Vigna radiate L., on the populations of English grain aphid, Sitobion avenae (F.) (Hemiptera: Aphididae), and its natural enemies were evaluated by field and laboratory experiments. The population densities of aphids and their natural enemies were evaluated in the intercropped field against different row ratio combinations of wheat-mung bean. Results showed that wheat-mung bean intercropping caused a drop in aphid densities, and the ratio 12 wheat: 4 mung bean brought about the largest drop (> 8%). In addition, the population densities of coccinellids (ladybirds) and parasitoids and the species diversity of all the natural enemies of aphid were higher in the intercropped field than in the field planted only with wheat. However, intercropping did not influence the community indices (evenness and index of dominance concentration) of the natural enemies. Y-tube olfactometer bioassays were carried out in the laboratory to test whether odor blends of host and nonhost plants affect the host selection of S. avenae. Bioassays indicated that both apterous and alate aphids significantly preferred host plant odor over odor blends of host and intercropped species. Hence, the olfactory-based host location of aphids in the field might be affected by intercropping. The intercropping experiment clearly showed that increased crop species diversity suppresses aphid population growth and preserves the population of natural enemies of aphids. Our results also provide support for the "resource concentration hypothesis" and the "enemies hypothesis".


Assuntos
Agricultura/métodos , Afídeos , Fabaceae , Cadeia Alimentar , Triticum/parasitologia , Animais , Afídeos/parasitologia , Besouros , Especificidade de Hospedeiro , Densidade Demográfica , Olfato , Vespas
14.
Mol Brain ; 15(1): 42, 2022 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-35534865

RESUMO

Neuropeptides act mostly on a class of G-protein coupled receptors, and play a fundamental role in the functions of neural circuits underlying behaviors. However, physiological functions of some neuropeptide receptors are poorly understood. Here, we used the molluscan model system Aplysia and microinjected the exogenous neuropeptide receptor apATRPR (Aplysia allatotropin-related peptide receptor) with an expression vector (pNEX3) into Aplysia neurons that did not express the receptor endogenously. Physiological experiments demonstrated that apATRPR could mediate the excitability increase induced by its ligand, apATRP (Aplysia allatotropin-related peptide), in the Aplysia neurons that now express the receptor. This study provides a definitive evidence for a physiological function of a neuropeptide receptor in molluscan animals.


Assuntos
Aplysia , Neuropeptídeos , Animais , Aplysia/fisiologia , Hormônios de Inseto , Neurônios/metabolismo , Neuropeptídeos/metabolismo , Receptores de Neuropeptídeos/metabolismo
15.
Sci Rep ; 12(1): 1213, 2022 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-35075137

RESUMO

Neuropeptides, as pervasive intercellular signaling molecules in the CNS, modulate a variety of behavioral systems in both protostomes and deuterostomes. Allatostatins are neuropeptides in arthropods that inhibit the biosynthesis of juvenile hormones. Based on amino acid sequences, they are divided into three different types in arthropods: allatostatin A, allatostatin B, allatostatin C. Allatostatin C (AstC) was first isolated from Manduca sexta, and it has an important conserved feature of a disulfide bridge formed by two cysteine residues. Moreover, AstC appears to be the ortholog of mammalian somatostatin, and it has functions in common with somatostatin, such as modulating feeding behaviors. The AstC signaling system has been widely studied in arthropods, but minimally studied in molluscs. In this study, we seek to identify the AstC signaling system in the marine mollusc Aplysia californica. We cloned the AstC precursor from the cDNA of Aplysia. We predicted a 15-amino acid peptide with a disulfide bridge, i.e., AstC, using NeuroPred. We then cloned two putative allatostatin C-like receptors and through NCBI Conserved Domain Search we found that they belonged to the G protein-coupled receptor (GPCR) family. In addition, using an inositol monophosphate 1 (IP1) accumulation assay, we showed that Aplysia AstC could activate one of the putative receptors, i.e., the AstC-R, at the lowest EC50, and AstC without the disulfide bridge (AstC') activated AstC-R with the highest EC50. Moreover, four molluscan AstCs with variations of sequences from Aplysia AstC but with the disulfide bridge activated AstC-R at intermediate EC50. In summary, our successful identification of the Aplysia AstC precursor and its receptor (AstC-R) represents the first example in molluscs, and provides an important basis for further studies of the AstC signaling system in Aplysia and other molluscs.


Assuntos
Aplysia/metabolismo , Neuropeptídeos/metabolismo , Sequência de Aminoácidos , Animais , Aplysia/genética , Células CHO , Cricetulus , Evolução Molecular , Neuropeptídeos/química , Neuropeptídeos/genética , Filogenia
16.
J Inflamm Res ; 14: 1165-1172, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33814922

RESUMO

OBJECTIVE: The aim of this study was to explore the role of the AI system which was designed and developed based on the characteristics of COVID-19 CT images in the screening and evaluation of COVID-19. METHODS: The research team adopted an improved U-shaped neural network to segment lungs and pneumonia lesions in CT images through multilayer convolution iterations. Then the appropriate 159 cases were selected to establish and train the model, and Dice loss function and Adam optimizer were used for network training with the initial learning rate of 0.001. Finally, 39 cases (29 positive and 10 negative) were selected for the comparative test. Experimental group: an attending physician a and an associate chief physician a read the CT images to diagnose COVID-19 with the help of the AI system. Control group: an attending physician b and an associate chief physician b did the diagnosis only by their experience, without the help of the AI system. The time spent by each doctor in the diagnosis and their diagnostic results were recorded. Paired t-test, univariate ANOVA, chi-squared test, receiver operating characteristic curves, and logistic regression analysis were used for the statistical analysis. RESULTS: There was statistical significance in the time spent in the diagnosis of different groups (P<0.05). For the group with the optimal diagnostic results, univariate and multivariate analyses both suggested no significant correlation for all variables, and thus it might be the assistance of the AI system, the epidemiological history and other factors that played an important role. CONCLUSION: The AI system developed by us, which was created due to COVID-19, had certain clinical practicability and was worth popularizing.

17.
Front Nutr ; 8: 685564, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34295917

RESUMO

Background: Dietary iron intake and serum ferritin in relation to severe headache or migraine remain largely unknown. Therefore, we investigated the associations between dietary iron intake and serum ferritin with severe headache or migraine among American adults. Methods: This cross-sectional study included 7,880 adults (≥20 years) from the National Health and Nutrition Examination Surveys (NHANES) of America from 1999 to 2004. We performed multivariable logistic regression and restricted cubic spline (RCS) regression to assess the association of dietary iron and serum ferritin with severe headache or migraine. Results: Most women aged 20-50 years consumed less dietary iron than their recommended dietary allowances. Dietary iron intake was inversely associated with severe headache or migraine in women aged 20-50 years. For women over 50 years, serum ferritin was negatively associated with severe headache or migraine. For men, there was no significant relationship between dietary iron and serum ferritin, and severe headache or migraine. Conclusions: Dietary iron intake has different effects on migraine in women of different ages, and this different effect may be due to age-related menstrual changes. Women aged 20-50 years should have a higher awareness of RDA and increase their dietary iron intake if needed, which may play an important role in preventing severe headache or migraine. Higher serum ferritin levels in women aged 50 and above may have a protective effect against migraine.

18.
Front Nutr ; 8: 653765, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33748178

RESUMO

Background: Migraine is a common neurological disorder and is affected by nutrients. Calcium and magnesium are essential minerals that play an important role in nerve function. So we investigated the association between dietary calcium and magnesium and migraine. Methods: We extracted 10,798 adults from the National Health and Nutrition Examination Surveys (NHANES) of America in 1999 to 2004. We classified patients who reported having severe headache or migraine as having possible migraine. Multivariable logistic regression and restricted cubic spline regression were conducted to determine the association between dietary calcium and magnesium and migraine. Results: We found that the adjusted ORs of the association between dietary calcium and magnesium and migraine for comparing the highest quintile intake with the lowest quintile intake were 0.77 (95% CI: 0.63-0.93, P = 0.008) and 0.69 (95% CI: 0.55-0.86, P = 0.001), respectively. For women, the adjusted ORs of dietary calcium and magnesium were 0.72 (95% CI: 0.56-0.93, P = 0.009) and 0.62 (95% CI: 0.47-0.83, P = 0.001), respectively. For men, the adjusted OR was 0.71 (95% CI: 0.52-0.97, P = 0.028) comparing the highest and the lowest quintile of calcium intake, but there was no statistically significant association between dietary magnesium intake and migraine. Joint analyses showed that the OR in the high-calcium and high-magnesium group was 0.74 (95% CI: 0.60-0.92, P = 0.006) compared with the low-calcium and low-magnesium group in women. Conclusions: High dietary intake of calcium and magnesium, independently or in combination, were inversely associated with migraine in women. For men, high dietary calcium was negatively related to migraine, but magnesium was not associated with migraine.

19.
J Zhejiang Univ Sci B ; 21(12): 940-947, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33843159

RESUMO

BACKGROUND: The proportion of recurrences after discharge among patients with coronavirus disease 2019 (COVID-19) was reported to be between 9.1% and 31.0%. Little is known about this issue, however, so we performed a meta-analysis to summarize the demographical, clinical, and laboratorial characteristics of non-recurrence and recurrence groups. METHODS: Comprehensive searches were conducted using eight electronic databases. Data regarding the demographic, clinical, and laboratorial characteristics of both recurrence and non-recurrence groups were extracted, and quantitative and qualitative analyses were conducted. RESULTS: Ten studies involving 2071 COVID-19 cases were included in this analysis. The proportion of recurrence cases involving patients with COVID-19 was 17.65% (between 12.38% and 25.16%) while older patients were more likely to experience recurrence (weighted mean difference (WMD)=1.67, range between 0.08 and 3.26). The time from discharge to recurrence was 13.38 d (between 12.08 and 14.69 d). Patients were categorized as having moderate severity (odds ratio (OR)=2.69, range between 1.30 and 5.58), while those with clinical symptoms including cough (OR=5.52, range between 3.18 and 9.60), sputum production (OR=5.10, range between 2.60 and 9.97), headache (OR=3.57, range between 1.36 and 9.35), and dizziness (OR=3.17, range between 1.12 and 8.96) were more likely to be associated with recurrence. Patients presenting with bilateral pulmonary infiltration and decreased leucocyte, platelet, and CD4+ T counts were at risk of COVID-19 recurrence (OR=1.71, range between 1.07 and 2.75; WMD=-1.06, range between -1.55 and -0.57, WMD=-40.39, range between -80.20 and -0.48, and WMD=-55.26, range between -105.92 and -4.60, respectively). CONCLUSIONS: The main factors associated with the recurrence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) after hospital discharge were older age, moderate severity, bilateral pulmonary infiltration, laboratory findings including decreased leucocytes, platelets, and CD4+ T counts, and clinical symptoms including cough, sputum production, headache, and dizziness. These factors can be considered warning indicators for the recurrence of SARS-CoV-2 and might help the development of specific management strategies.


Assuntos
COVID-19/diagnóstico , Recidiva , Fatores Etários , Contagem de Células Sanguíneas , Contagem de Linfócito CD4 , COVID-19/patologia , Tosse , Tontura , Cefaleia , Humanos , Alta do Paciente , Fatores de Risco
20.
J Trauma ; 67(6): 1213-9, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20009669

RESUMO

BACKGROUND: To investigate the effects of different resuscitation fluids on acute lung injury in a rat model of uncontrolled hemorrhagic shock (HS) followed by mimicked infection. METHODS: Sixty Sprague-Dawley rats were randomly assigned to one of the five groups (n = 12 per group) to receive the following treatments: (1) control group (group C), surgery, no hemorrhage, and no resuscitation; (2) no fluid resuscitation group; (3) lactated Ringer's solution group; (4) 7.5% hypertonic saline (HTS) group; and (5) hydroxyethyl starch group (group HES). All experimental groups were subjected to three phases: phase I entailed massive hemorrhage with a mean arterial pressure of 35 mm Hg to 40 mm Hg for 60 minutes by tail amputation and followed by mimicked infection by intratracheal administration of lipopolysaccharide 2 mg/kg. The animals in each group were then partially resuscitated with the fluid assigned to the group. Phase II of 60 minutes commenced at tail ligation, involved hemostasis, and return of all the blood initially shed. Phase III was an observation phase with no any further treatment and lasted for 3.5 hours. The survival rate at the end of the phase III was recorded. After phase III, arterial blood gases were recorded. The wet to dry lung weight ratio, pulmonary microvascular permeability, the expression of transforming growth factor (TGF)-beta1, and Smad2 were determined. The lung histology was also assessed. RESULTS: HES and HTS solutions were more effective than no fluid resuscitation and lactated Ringer's solution in reducing the detrimental effects of HS and infection on the lungs, as seen by the significantly lower pulmonary microvascular permeability and wet to dry lung weight ratio, the improved arterial blood gases and lower levels of TGF-beta1and Smad2 expression in lung tissues. These beneficial effects were most pronounced in the group HES. CONCLUSIONS: This study demonstrated that resuscitation with HTS and especially with HES could reduce lung tissue damage and pulmonary edema after severe uncontrolled HS. The TGF-beta1/Smad2 signaling pathway might play a key role in regulation of pulmonary permeability and formation of pulmonary edema in a rat model of uncontrolled HS and infection.


Assuntos
Hidratação/métodos , Lesão Pulmonar/etiologia , Lesão Pulmonar/terapia , Ressuscitação/métodos , Choque Hemorrágico/complicações , Choque Hemorrágico/terapia , Doença Aguda , Análise de Variância , Animais , Gasometria , Western Blotting , Líquido da Lavagem Broncoalveolar , Permeabilidade Capilar , Modelos Animais de Doenças , Derivados de Hidroxietil Amido/administração & dosagem , Derivados de Hidroxietil Amido/farmacologia , Técnicas Imunoenzimáticas , Infusões Intravenosas , Soluções Isotônicas/administração & dosagem , Soluções Isotônicas/farmacologia , Lipopolissacarídeos , Lesão Pulmonar/fisiopatologia , Reação em Cadeia da Polimerase , RNA Mensageiro/análise , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Lactato de Ringer , Solução Salina Hipertônica/administração & dosagem , Solução Salina Hipertônica/farmacologia , Choque Hemorrágico/fisiopatologia , Proteína Smad2/análise
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