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1.
Front Aging Neurosci ; 16: 1334011, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38440099

RESUMO

Objective: Cerebral small vessel disease (CSVD) is the most common vascular cause of cognitive impairment. This study aimed to explore the association between MTHFR C677T polymorphism and cognitive impairment in CSVD patients. Methods: Demographic, medical, laboratory, cognitive evaluation, and MTHFR C677T polymorphism data were collected from CSVD patients admitted to our hospital between January 2019 and July 2023. Inclusion criteria for CSVD were based on the Standards for Reporting Vascular changes on Neuroimaging (STRIVE) criteria, with age ≥ 45 years. Binary logistic regression models were used to analyze risk factors associated with WMH and cognitive impairment. Results: A total of 330 CSVD participants were recruited in this study, including 179 male and 151 female, with a median age of 64 years (interquartile range: 58-73 years). There were 185 patients (56.1%) with cognitive impairment, 236 patients (71.5%) with WMH, 89 patients (27.0%) with CMB, 87 patients (26.4%) with lacunes. All participants completed MTHFR polymorphism analysis, 149 cases (45.2%) of the CC genotype, 112 cases (33.9%) of the CT genotype and 69 cases (20.9%) of the TT genotype. Patients with TT genotype exhibited higher plasma homocysteine levels and more severe WMH and cognitive impairment (p < 0.001). Multivariable binary logistic regression model showed that WMH was significantly associated with age (p = 0.019), history of hypertension (p = 0.011), HHcy (p = 0.019) and MTHFR genotype (p = 0.041); while cognitive impairment was significantly associated with age (p = 0.033), history of hypertension (p = 0.019), HHcy (p = 0.040), MTHFR genotype (p = 0.039), WMH (p = 0.041), and lacunes (p = 0.001). Conclusion: In this cross-sectional study, we investigated the association between MTHFR C677T polymorphism and cognitive function in CSVD patients. We found that MTHFR 677 TT genotype was an independent risk factor for the progression of WMH and cognitive impairment in CSVD patients.

2.
Technol Health Care ; 2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37980577

RESUMO

BACKGROUND: The use of indwelling closed thoracic drainage tubes in the wedge resection of the lungs is of great significance to postoperative recovery. However, there are potential risks. OBJECTIVE: To explore the design feasibility and application effect of triple-buffer-system-fixed small-diameter (18 F) thoracic closed drainage tubes following lung wedge resection. METHODS: A total of 136 patients with indwelling thoracic drainage tubes following pulmonary wedge resection were recruited, with 70 patients allocated to the control group and 66 to the experimental group. The drainage tube in the experimental group was fixed with the triple-buffer system, while that in the control group was fixed using the conventional lifting platform method. The incidence of unplanned extubation, the indwelling time of the drainage tube and the time and material costs, as well as information regarding any subcutaneous emphysema and skin tension blisters, were recorded following the operation. The pain and degree of comfort were assessed using a chi-square test and a rank sum t-test to compare the differences between the two groups. RESULTS: There were no statistically significant differences in terms of age, gender and sweating between the two groups. Compared with the control group, the unplanned extubation rate of the experimental group was lower (χ2= 8.513; P= 0.004), the indwelling time of the drainage tube was shorter (t= 2.108; P= 0.037), the cumulative material cost was lower (t= 3.778; P< 0.001), the time cost was also lower (Z= 2.717; P= 0.008), the degree of comfort was higher (Z= 2.752; P= 0.006), and the degree of pain was lower (Z= 4.019; P< 0.001). The incidence of subcutaneous emphysema was significantly lower in the experimental group than in the control group (χ2= 8.513; P= 0.004). CONCLUSION: The use of the triple-buffer system to fix small-diameter (18 F) thoracic closed drainage tubes can reduce the unplanned extubation rate, indwelling time of the drainage tube and the incidence of adverse reactions.

3.
Front Pediatr ; 11: 1005383, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36911015

RESUMO

Objective: To describe the rate of hypertensive disorder of pregnancy (HDP) among mothers of very preterm infants (VPIs) admitted to Chinese neonatal intensive care units (NICUs), and to investigate the relationship between HDP and the outcomes of VPIs. Study design: Cohort study of all VPIs born at a gestational age of 24+0-31+6 weeks and admitted to 57 tertiary NICUs of the Chinese Neonatal Network (CHNN) in 2019. Infants with severe congenital anomalies or missing maternal HDP information were excluded. Two multivariate logistic regression models were generated to assess the relationship between HDP and neonatal outcomes. Results: Among 9,262 infants enrolled, 1,744 (18.8%) infants were born to mothers with HDP, with an increasing incidence with increasing gestational age. VPIs born to mothers with HDP had higher gestational age but lower birth weight and were more likely to be small for gestational age. Mothers with HDP were more likely to receive antenatal steroids, MgSO4 and cesarean section. Infants in the HDP group showed higher observed rates of mortality or any morbidity than infants in the non-HDP group (50.2% vs. 47.2%, crude odds ratio (OR) 1.13, 95% CI 1.02-1.26). However, the associations between HDP and adverse outcomes were not significant after adjustment. In the HDP group, mothers of 1,324/1,688 (78.4%) infants were diagnosed with preeclampsia/eclampsia. Infants born to mothers with preeclampsia/eclampsia had significantly lower odds of early death and severe retinopathy of prematurity. Conclusions: Nearly one-fifth of VPIs were born to mothers with HDP in Chinese NICUs. No significant association was identified between HDP and adverse neonatal short-term outcomes of VPIs, while long-term follow-up of these infants is needed.

4.
Insect Biochem Mol Biol ; 152: 103895, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36538995

RESUMO

Endoparasitoid wasps inject venom proteins into the hemocoel of host insects to ensure survival, growth, and development of their progenies by blocking host immunity. We previously identified ten serine protease inhibitors of the serpin superfamily in venom of the endoparasitoid wasp, Microplitis mediator, but it is unclear how these inhibitors may interact with host immune serine proteases. In this study, we investigated the functions of two serpins, MmvSPN-1 and MmvSPN-2, in the regulation of humoral immune responses in two hosts, the oriental armyworm Pseudaletia separate and the cotton bollworm Helicoverpa armigera, by dsRNA knockdown and biochemical assays using recombinant proteins. Knockdown of the two serpins resulted in increases in prophenoloxidase (PPO) activation and antimicrobial peptide (AMP) production in the hosts. After injection into the host hemocoel, the recombinant serpins inhibited PPO activation and AMP transcription. Mass spectrometry analysis of the pull-downs and in vitro reconstitution experiments revealed that HacSP29, a clip-domain serine protease in H. armigera, is the target of these two serpins. Therefore, these two inhibitors in the wasp venom may protect eggs from attacks by melanization and AMPs in the host insects.


Assuntos
Mariposas , Serpinas , Vespas , Animais , Vespas/metabolismo , Serpinas/genética , Serpinas/metabolismo , Serina Endopeptidases , Mariposas/genética , Mariposas/metabolismo , Venenos de Vespas/metabolismo , Serina Proteases/genética , Serina Proteases/metabolismo , Peptídeos Antimicrobianos , Proteínas de Insetos/metabolismo
5.
Insect Sci ; 30(3): 677-692, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36271788

RESUMO

Endoparasitoid wasps introduce venom into their host insects during the egg-laying stage. Venom proteins play various roles in the host physiology, development, immunity, and behavior manipulation and regulation. In this study, we identified a venom protein, MmRho1, a small guanine nucleotide-binding protein derived from ovary in the endoparasitoid wasp Microplitis mediator and found that knockdown of its expression by RNA interference caused down-regulation of vitellogenin and juvenile hormone, egg production, and cocoons formation in the female wasps. We demonstrated that MmRho1 entered the cotton bollworm's (host) hemocytes and suppressed cellular immune responses after parasitism using immunofluorescence staining. Furthermore, wasp MmRho1 interacted with the cotton bollworm's actin cytoskeleton rearrangement regulator diaphanous by yeast 2-hybrid and glutathione s-transferase pull-down. In conclusion, this study indicates that MmRho1 plays dual roles in wasp development and the suppression of the host insect cellular immune responses.


Assuntos
Imunidade Celular , Vespas , Animais , Feminino , Interações Hospedeiro-Parasita , Venenos de Vespas/metabolismo , Vespas/fisiologia
6.
Langmuir ; 38(34): 10385-10391, 2022 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-35980392

RESUMO

Microbe-catalyzed surface modification is a promising method for the production of special targeting nanomaterials. A bacterium-selective material can be obtained by investigating the microbe-catalyzed mineralization of proteins. Herein, a novel method was fabricated for the biosynthesis of FeS-decorated porphyrin-protein clusters (P-CA@BE) via E. coli (Escherichia coli)-catalyzed bio-Fe(III) reduction and bio-sulfidation of porphyrin (P), caffeic acid (CA), and protein [bovine serum albumin (BSA)] assemblies. The assembly (P-CA@BSA) was identified by spectroscopic methods. Next, the P-CA@BSA assembly was transferred into FeS-decorated porphyrin-protein clusters (P-CA@BE) catalyzed by E. coli. There are partial ß-folding proteins in P-CA@BE, which selectively recognize S. aureus (Staphylococcus aureus) and show different antibacterial properties against E. coli and S. aureus. Results demonstrate that the E. coli-catalyzed mineralization of the porphyrin-protein assembly is an effective method for the biosynthesis of S. aureus-sensitive metal-protein clusters.


Assuntos
Porfirinas , Staphylococcus aureus , Proteínas de Bactérias , Escherichia coli , Compostos Férricos/química , Compostos Ferrosos , Porfirinas/farmacologia , Soroalbumina Bovina/química
7.
Transl Pediatr ; 11(6): 1001-1009, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35800274

RESUMO

Background: Hyperbilirubinemia is the most common cause of neonatal hospitalization and, although it generally has a good prognosis, a significant percentage of neonatal patients maintain a high bilirubin level, which can lead to severe complications, including lifelong disability such as growth retardation, encephalopathy, autism and hearing impairment. The study of risk factors for neonatal hyperbilirubinemia has been controversial. Therefore, we evaluated the risk factors of neonatal hyperbilirubinemia using a meta-analysis. Methods: Relevant English and Chinese studies that discussed risk factors for neonatal hyperbilirubinemia were retrieved from the PubMed, EMBASE, Medline, Central, China National Knowledge Infrastructure (CNKI), Wanfang and China Science Digital Library (CSDL). The literature took newborns as the research object, set up a control group, and observed the relationship between exposure factors and neonatal hyperbilirubinemia. The combined effect size was expressed by odds ratio (OR) and 95% confidence interval (CI). The Chi-square test was used to test heterogeneity of the studies, and if it existed, subgroup analyses were used to explore the source of heterogeneity, and the random-effects model was selected for the combined analysis. The fixed-effects model was chosen for the combined analysis if there was no heterogeneity. Publication bias was assessed using Egger's test and funnel plot. Results: Risk factors for neonatal hyperbilirubinemia were exclusive breastfeeding (BF: OR =1.74, 95% CI: 1.42, 2.12, Z=5.43, P<0.00001); glucose-6-phosphate dehydrogenase deficiency (G6PD: OR =1.62, 95% CI: 1.44, 1.81, Z=8.39, P<0.00001); maternal-fetal ABO blood group incompatibility (OR =1.64, 95% CI: 1.42, 1.89, Z=6.75, P<0.00001); and preterm birth (PTB: OR =1.31, 95% CI: 1.17, 1.47, Z=4.60, P<0.00001); there was no heterogeneity or publication bias among the studies (BF: χ2=5.34, P=0.25, I2=25%; G6PD: χ2=4.40, P=0.49, I2=0%; ABO: χ2=1.91, P=0.75, I2=0%; PTB: χ2=0.81, P=0.67, I2=0%). Conclusions: Exclusive breastfeeding, G6PD deficiency, ABO incompatibility and premature birth were confirmed as risk factors for neonatal hyperbilirubinemia. Pregnant women with risk factors should be monitored more closely and clinical intervention should be given in a timely manner.

8.
J Glob Optim ; : 1-23, 2022 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-35601808

RESUMO

Data uncertainty has a great impact on portfolio selection. Based on the popular mean-absolute deviation (MAD) model, we investigate how to make robust portfolio decisions. In this paper, a novel Wasserstein metric-based data-driven distributionally robust mean-absolute deviation (DR-MAD) model is proposed. However, the proposed model is non-convex with an infinite-dimensional inner problem. To solve this model, we prove that it can be transformed into two simple finite-dimensional linear programs. Consequently, the problem can be solved as easily as solving the classic MAD model. Furthermore, the proposed DR-MAD model is compared with the 1/N, classic MAD and mean-variance model on S &P 500 constituent stocks in six different settings. The experimental results show that the portfolios constructed by DR-MAD model are superior to the benchmarks in terms of profitability and stability in most fluctuating markets. This result suggests that Wasserstein distributionally robust optimization framework is an effective approach to address data uncertainty in portfolio optimization.

9.
Transl Pediatr ; 11(4): 556-564, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35558974

RESUMO

Background: This study aimed to explore the main risk factors for cerebral palsy in children by meta-analysis of the literature on the risk factors of cerebral palsy. Methods: We performed a literature search of the PubMed, EMBASE, Medline, and CENTRAL databases using the following search terms: ("cerebrl plsy" or "cerebrl plsis" or "infantile cerebral palsy") and ("risk factors"). Case-control or cohort studies of children with cerebral palsy and healthy children were included for meta-analysis. The Newcastle-Ottawa Scale (NOS) of case-control studies was used to evaluate the quality of the included studies. The Chi-square test was used to test the heterogeneity of the literature. This study used subgroup analysis and sensitivity analysis to identify sources of heterogeneity. If subgroup analyses and sensitivity analyses could not identify the source of heterogeneity, no pooling between study results was performed, and only individual study results were described. In this study, Egger's test was used to test for publication bias. The random-effects model was used when heterogeneity existed, and the fixed-effect model was applied when heterogeneity did not exist. Results: A total of 1,836 related articles were retrieved. After screening, 13 articles were included in the analysis, involving a total of 2,489 children with cerebral palsy and 4,782 children without cerebral palsy. None of the included articles achieved a NOS score of 9, four articles scored 8, eight articles scored 7, and one article scored 6. Meta-analysis showed that maternal hypertension during pregnancy, premature rupture of membranes, premature delivery and emergency cesarean section were risk factors for cerebral palsy in children, and there was no heterogeneity among the literatures and no publication bias. Conclusions: This study identified gestational hypertension, preterm birth, premature rupture of membranes, and emergency cesarean section as risk factors for cerebral palsy in children through meta-analysis, providing a reference for risk monitoring and clinical intervention.

10.
Artigo em Inglês | MEDLINE | ID: mdl-37015655

RESUMO

In real applications, it is often that the collected multiview data contain missing views. Most existing incomplete multiview clustering (IMVC) methods cannot fully utilize the underlying information of missing data or sufficiently explore the consistent and complementary characteristics. In this article, we propose a novel Low-rAnk Tensor regularized viEws Recovery (LATER) method for IMVC, which jointly reconstructs and utilizes the missing views and learns multilevel graphs for comprehensive similarity discovery in a unified model. The missing views are recovered from a common latent representation, and the recovered views conversely improve the learning of shared patterns. Based on the shared subspace representations and recovered complete multiview data, the multilevel graphs are learned by self-representation to fully exploit the consistent and complementary information among views. Besides, a tensor nuclear norm regularizer is introduced to pursue the global low-rank property and explore the interview correlations. An alternating direction minimization algorithm is presented to optimize the proposed model. Moreover, a new initialization method is proposed to promote the effectiveness of our method for latent representation learning and missing data recovery. Extensive experiments demonstrate that our method outperforms the state-of-the-art approaches.

11.
J Perianesth Nurs ; 36(5): 480-486.e1, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34183256

RESUMO

PURPOSE: This study aims to compare the incidence of complications when using a new approach to secure an indwelling peripheral venous catheter (PVC), involving tying of the tube with a surgical knot at two places and several layers of elastic adhesive bandage, with a standard approach using sterile, transparent, and protective film. METHODS: This study enrolled 311 consecutive adults undergoing thoracoscopic lobectomy under general anesthesia at Taizhou Hospital of Zhejiang Province between October 2017 and May 2018. Patients were randomized to experimental and control groups and were followed for up to 72 hours. The primary endpoint was dislodgement of the PVC. Secondary endpoints were blood in the catheter; analgesia pump obstruction alarm; time taken and cost of PVC replacement; replacement of securing materials and analgesia pump line; and time and cost of replacing them. All adverse events were recorded. FINDINGS: Final analysis included 248 patients (experimental group: n = 126; control group: n = 122). PVC dislodgement was less frequent in the experimental group than in the control group. In the control group, 78.7% of patients required replacement of securing materials (costing 37 cents each time) and 13.1% required PVC replacement (costing 3.6 dollars each time), necessitating additional nursing time. No patients in the experimental group required replacement of the PVC or securing materials. Blisters were less common in the experimental group than in the control group (0% vs 9.84%, P < .001). No patients had limb edema. CONCLUSIONS: This new method of securing an analgesia pump line can reduce traction on the indwelling PVC, lowering the dislodgement rate.


Assuntos
Analgesia , Cateterismo Periférico , Adulto , Analgésicos , Bandagens , Cateterismo Periférico/efeitos adversos , Cateteres de Demora , Humanos , Manejo da Dor
12.
Autophagy ; 17(5): 1170-1192, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-32324083

RESUMO

CTSD/CathD/CATD (cathepsin D) is a lysosomal aspartic protease. A distinguishing characteristic of CTSD is its dual functions of promoting cell proliferation via secreting a pro-enzyme outside the cells as a ligand, and promoting apoptosis via the mature form of this enzyme inside cells; however, the regulation of its secretion, expression, and maturation is undetermined. Using the lepidopteran insect Helicoverpa armigera, a serious agricultural pest, as a model, we revealed the dual functions and regulatory mechanisms of CTSD secretion, expression, and maturation. Glycosylation of asparagine 233 (N233) determined pro-CTSD secretion. The steroid hormone 20-hydroxyecdysone (20E) promoted CTSD expression. Macroautophagy/autophagy triggered CTSD maturation and localization inside midgut cells to activate CASP3 (caspase 3) and promote apoptosis. Pro-CTSD was expressed in the pupal epidermis and was secreted into the hemolymph to promote adult fat body endoreplication/endoreduplication, cell proliferation, and association. Our study revealed that the differential expression and autophagy-mediated maturation of CTSD in tissues determine its roles in apoptosis and cell proliferation, thereby determining the cell fates of tissues during lepidopteran metamorphosis.Abbreviations: 20E: 20-hydroxyecdysone; 3-MA: 3-methyladenine; ACTB/ß-actin: actin beta; AKT: protein kinase B; ATG1: autophagy-related 1; ATG4: autophagy-related 4; ATG5: autophagy-related 5; ATG7: autophagy-related 7; ATG14: autophagy-related 14; BSA: bovine serum albumin; CASP3: caspase 3; CQ: choroquine; CTSD: cathepsin D; DAPI: 4',6-diamidino-2-phenylindole; DMSO: dimethyl sulfoxide; DPBS: dulbecco's phosphate-buffered saline; DsRNA: double-stranded RNA; EcR: ecdysone receptor; EcRE: ecdysone response element; EdU: 5-ethynyl-2´-deoxyuridine; G-m-CTSD: glycosylated-mautre-CTSD; G-pro-CTSD: glycosylated-pro-CTSD; HaEpi: Helicoverpa armigera epidermal cell line; HE staining: hematoxylin and eosin staining; IgG: immunoglobin G; IM: imaginal midgut; JH: juvenile hormone; Kr-h1: krueppel homologous protein 1; LM: larval midgut; M6P: mannose-6-phosphate; PBS: phosphate-buffered saline; PCD: programmed cell death; PNGase: peptide-N-glycosidase F; RFP: red fluorescent protein; RNAi: RNA interference; SDS-PAGE: sodium dodecyl sulfate-polyacrylamide gel electrophoresis; SYX17: syntaxin 17; USP1: ultraspiracle isoform 1.


Assuntos
Apoptose/fisiologia , Autofagia/fisiologia , Catepsina D/metabolismo , Animais , Autofagia/genética , Proliferação de Células/fisiologia , Ecdisterona/metabolismo , Técnicas de Silenciamento de Genes , Lisossomos/metabolismo , Receptores de Esteroides/metabolismo
13.
PLoS Pathog ; 16(6): e1008627, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32584915

RESUMO

Different from holometabolous insects, the hemipteran species such as pea aphid Acyrthosiphon pisum exhibit reduced immune responses with the absence of the genes coding for antimicrobial peptide (AMP), immune deficiency (IMD), peptidoglycan recognition proteins (PGRPs), and other immune-related molecules. Prior studies have proved that phenoloxidase (PO)-mediated melanization, hemocyte-mediated phagocytosis, and reactive oxygen species (ROS) participate in pea aphid defense against bacterial infection. Also, the conserved signaling, Jun N-terminal kinase (JNK) pathway, has been suggested to be involved in pea aphid immune defense. However, the precise role of the JNK signaling, its interplay with other immune responses and its regulation in pea aphid are largely unknown. In this study, using in vitro biochemical assays and in vivo bioassays, we demonstrated that the JNK pathway regulated hemolymph PO activity, hydrogen peroxide concentration and hemocyte phagocytosis in bacteria infected pea aphids, suggesting that the JNK pathway plays a central role in regulating immune responses in pea aphid. We further revealed the JNK pathway is regulated by microRNA-184 in response to bacterial infection. It is possible that in common the JNK pathway plays a key role in immune system of hemipteran insects and microRNA-184 regulates the JNK pathway in animals.


Assuntos
Afídeos/imunologia , Proteínas de Insetos/imunologia , MAP Quinase Quinase 4/imunologia , MicroRNAs/imunologia , Transdução de Sinais/imunologia , Animais , Afídeos/genética , Proteínas de Insetos/genética , MAP Quinase Quinase 4/genética , MicroRNAs/genética , Fagocitose/genética , Transdução de Sinais/genética
14.
J Biol Chem ; 294(41): 14922-14936, 2019 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-31413111

RESUMO

Oligomerization of stromal interacting molecule 1 (STIM1) promotes store-operated calcium entry (SOCE); however, the mechanism of STIM1 aggregation is unclear. Here, using the lepidopteran insect and agricultural pest cotton bollworm (Helicoverpa armigera) as a model and immunoblotting, RT-qPCR, RNA interference (RNAi), and ChIP assays, we found that the steroid hormone 20-hydroxyecdysone (20E) up-regulates STIM1 expression via G protein-coupled receptors (GPCRs) and the 20E nuclear receptor (EcRB1). We also identified an ecdysone-response element (EcRE) in the 5'-upstream region of the STIM1 gene and also noted that STIM1 is located in the larval midgut during metamorphosis. STIM1 knockdown in larvae delayed pupation time, prevented midgut remodeling, and decreased 20E-induced gene transcription. STIM1 knockdown in a H. armigera epidermal cell line, HaEpi, repressed 20E-induced calcium ion influx and apoptosis. Moreover, 20E-induced STIM1 clustering to puncta and translocation toward the cell membrane. Inhibitors of GPCRs, phospholipase C (PLC), and inositol trisphosphate receptor (IP3R) repressed 20E-induced STIM1 phosphorylation, and we found that two GPCRs are involved in 20E-induced STIM1 phosphorylation. 20E-induced STIM1 phosphorylation on Ser-485 through protein kinase C (PKC), and we observed that Ser-485 phosphorylation is critical for STIM1 clustering, interaction with calcium release-activated calcium channel modulator 1 (Orai1), calcium ion influx, and 20E-induced apoptosis. These results suggest that 20E up-regulates STIM1 phosphorylation for aggregation via GPCRs, followed by interaction with Orai1 to induce SOCE, thereby promoting apoptosis in the midgut during insect metamorphosis.


Assuntos
Cálcio/metabolismo , Ecdisterona/farmacologia , Agregados Proteicos/efeitos dos fármacos , Molécula 1 de Interação Estromal/metabolismo , Animais , Apoptose/efeitos dos fármacos , Transporte Biológico/efeitos dos fármacos , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Larva/metabolismo , Lepidópteros/efeitos dos fármacos , Lepidópteros/crescimento & desenvolvimento , Lepidópteros/metabolismo , Metamorfose Biológica/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Receptores Acoplados a Proteínas G/metabolismo , Transdução de Sinais/efeitos dos fármacos , Molécula 1 de Interação Estromal/deficiência , Molécula 1 de Interação Estromal/genética , Regulação para Cima/efeitos dos fármacos
15.
Nat Prod Res ; 33(1): 41-46, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29382221

RESUMO

Six triterpenoids (1-6), four megastigmanes (7-10) and five hydroxycinnamic acid derivatives (11-15) were isolated from the aerial part of Anisomeles indica (Lamiaceae). Of these components, compound 1 was identified to be a new triterpenoid with the structure of 2α,3α,19α-trihydroxyurs-12,20(30)-dien-28-oic acid based on extensive analysis of MS, 1D and 2D NMR spectroscopic data, while compounds 2-13 were obtained for the first time from Anisomeles species.


Assuntos
Ácidos Cumáricos/isolamento & purificação , Lamiaceae/química , Norisoprenoides/isolamento & purificação , Triterpenos/isolamento & purificação , Ácidos Cumáricos/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Norisoprenoides/química , Componentes Aéreos da Planta/química , Extratos Vegetais/química , Triterpenos/química
16.
J Biol Chem ; 293(48): 18613-18623, 2018 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-30305395

RESUMO

Insulin promotes larval growth of insects by stimulating the synthesis of the steroid hormone 20-hydroxyecdysone (20E), which induces pupation and apoptosis. However, the mechanism underlying the coordinate regulation of insect pupation and apoptosis by these two functionally opposing hormones is still unclear. Here, using the lepidopteran insect and serious agricultural pest Helicoverpa armigera (cotton bollworm) as a model, we report that phosphoinositide-dependent kinase-1 (PDK1) and forkhead box O (FoxO) play key roles in these processes. We found that the transcript levels of the PDK1 gene are increased during the larval feeding stages. Moreover, PDK1 expression was increased by insulin, but repressed by 20E. dsRNA-mediated PDK1 knockdown in the H. armigera larvae delayed pupation and resulted in small pupae and also decreased Akt/protein kinase B expression and increased FoxO expression. Furthermore, the PDK1 knockdown blocked midgut remodeling and decreased 20E levels in the larvae. Of note, injecting larvae with 20E overcame the effect of the PDK1 knockdown and restored midgut remodeling. FoxO overexpression in an H. armigera epidermal cell line (HaEpi) did not induce apoptosis, but promoted autophagy and repressed cell proliferation. These results reveal cross-talk between insulin and 20E and that both hormones oppose each other's activities in the regulation of insect pupation and apoptosis by controlling PDK1 expression and, in turn, FoxO expression. We conclude that sufficiently high 20E levels are a key factor for inducing apoptosis during insect pupation.


Assuntos
Proteínas Quinases Dependentes de 3-Fosfoinositídeo/metabolismo , Ecdisterona/fisiologia , Proteínas de Insetos/metabolismo , Insulina/fisiologia , Lepidópteros/crescimento & desenvolvimento , Pupa/crescimento & desenvolvimento , Proteínas Quinases Dependentes de 3-Fosfoinositídeo/genética , Animais , Apoptose/genética , Autofagia/genética , Proliferação de Células/genética , Fatores de Transcrição Forkhead/genética , Técnicas de Silenciamento de Genes , Larva/crescimento & desenvolvimento , Fosforilação , RNA Mensageiro/metabolismo
17.
Cell Calcium ; 68: 24-33, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29129205

RESUMO

Animal steroid hormones stimulate extracellular Ca2+ influx into cells; however, the mechanism remains unclear. In this study, we determined that the Ca2+ influx induced by steroid hormone 20-hydroxyecdysone (20E) is mediated by the calcium release-activated calcium channel modulator 1 (CRACM1/Orai1). The Orai1 mRNA is highly expressed during midgut programmed cell death in the lepidopteran insect Helicoverpa armigera. 20E upregulated the expression of Orai1 in H. armigera larvae and in an epidermal cell line (HaEpi). Knockdown of Orai1 in HaEpi cells blocked 20E-induced Ca2+ influx, and the inhibitor of inositol 1, 4, 5-trisphosphate receptor (IP3R) Xestospongin (XeC) blocked 20E-induced Ca2+ influx, suggesting that 20E, via Orai1, induces stored-operated Ca2+ influx. Orai1 interacts with stromal interaction molecule 1(Stim1) to exert its function in 20E-induced Ca2+ influx. 20E promotes Orai1 aggregation through G-protein-coupled receptors, phospholipase C gamma 1, and Stim1. Knockdown of Orai1 in the HaEpi cell line repressed apoptosis and maintained autophagy under 20E regulation. Knockdown of Orai1 in larvae delayed pupation, repressed midgut apoptosis, maintained the midgut in an autophagic state, and repressed 20E-pathway gene expression. These results revealed that steroid hormone 20E, via Orai1, induces Ca2+ influx to promote the transition of midgut from autophagy to apoptosis.


Assuntos
Apoptose/efeitos dos fármacos , Cálcio/metabolismo , Sistema Digestório/citologia , Ecdisterona/farmacologia , Mariposas/citologia , Proteína ORAI1/metabolismo , Regulação para Cima/efeitos dos fármacos , Animais , Autofagia/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Modelos Biológicos , Muda/efeitos dos fármacos , Proteína ORAI1/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores Acoplados a Proteínas G/metabolismo
18.
Proc Natl Acad Sci U S A ; 114(34): E7121-E7130, 2017 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-28790182

RESUMO

The nuclear receptor EcRB1, which is activated by the insect steroid hormone 20-hydroxyecdysone (20E), is reportedly phosphorylated by a protein kinase after 20E induction. However, the protein kinase has not been identified, and the significance of EcRB1 phosphorylation is unclear. In this study, we identified a protein kinase C δ (PKCδ) isoform (the E isoform) that phosphorylates EcRB1 in the lepidopteran Helicoverpa armigera, a serious agricultural pest worldwide, to promote apoptotic gene expression and apoptosis during metamorphosis. Through activation of the EcRB1/USP1 transcription complex by 20E, PKCδ expression was up-regulated in several tissues during the metamorphic stage. Knockdown of PKCδ caused failure to transition from larvae to pupae, prevented tissues from undergoing programmed cell death (PCD), and down-regulated the expression of the transcription factor Brz-7 and the apoptosis executors caspase-3 and caspase-6 The threonine residue at position 1343 of PKCδ was phosphorylated and was critical for its proapoptotic function. Overexpression of the PKCδ catalytic domain was localized to the nuclei in HaEpi cells, which increased caspase-3 activity and apoptosis. PKCδ directly phosphorylated a threonine residue at position 468 in the amino acid sequence of EcRB1. The phosphorylation of EcRB1 was critical for its heterodimeric interaction with the USP1 protein and for binding to the ecdysone response element. The data suggested that 20E up-regulates PKCδ expression to regulate EcRB1 phosphorylation for EcRB1/USP1 transcription complex formation, apoptotic gene transcription, and apoptosis.


Assuntos
Apoptose , Ecdisterona/farmacologia , Proteínas de Insetos/metabolismo , Mariposas/metabolismo , Proteína Quinase C-delta/metabolismo , Receptores de Esteroides/metabolismo , Animais , Apoptose/efeitos dos fármacos , Núcleo Celular/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Proteínas de Insetos/genética , Larva/efeitos dos fármacos , Larva/genética , Larva/crescimento & desenvolvimento , Larva/metabolismo , Metamorfose Biológica/efeitos dos fármacos , Mariposas/efeitos dos fármacos , Mariposas/genética , Mariposas/crescimento & desenvolvimento , Fosforilação/efeitos dos fármacos , Proteína Quinase C-delta/genética , Receptores de Esteroides/genética , Elementos de Resposta , Proteases Específicas de Ubiquitina/genética , Proteases Específicas de Ubiquitina/metabolismo
19.
Opt Express ; 16(19): 15238-48, 2008 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-18795062

RESUMO

In this paper we present novel light trapping designs applied to multiple junction thin film solar cells. The new designs incorporate one dimensional photonic crystals as band pass filters that reflect short light wavelengths (400 - 867 nm) and transmit longer wavelengths(867 -1800 nm) at the interface between two adjacent cells. In addition, nano structured diffractive gratings that cut into the photonic crystal layers are incorporated to redirect incoming waves and hence increase the optical path length of light within the solar cells. Two designs based on the nano structured gratings that have been realized using the scattering matrix and particle swarm optimization methods are presented. We also show preliminary fabrication results of the proposed devices.


Assuntos
Desenho Assistido por Computador , Fontes de Energia Elétrica , Membranas Artificiais , Modelos Teóricos , Refratometria/instrumentação , Energia Solar , Simulação por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Fótons
20.
Appl Opt ; 47(10): B1-10, 2008 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-18382544

RESUMO

The size of infrared camera systems can be reduced by collecting low-resolution images in parallel with multiple narrow-aperture lenses rather than collecting a single high-resolution image with one wide-aperture lens. We describe an infrared imaging system that uses a three-by-three lenslet array with an optical system length of 2.3 mm and achieves Rayleigh criteria resolution comparable with a conventional single-lens system with an optical system length of 26 mm. The high-resolution final image generated by this system is reconstructed from the low-resolution images gathered by each lenslet. This is accomplished using superresolution reconstruction algorithms based on linear and nonlinear interpolation algorithms. Two implementations of the ultrathin camera are demonstrated and their performances are compared with that of a conventional infrared camera.

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