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1.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 46(1): 19-24, 2024 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-38433626

RESUMO

Objective To analyze the current situation of dietary diversity and caregiver self-efficacy for complementary feeding among infants and young children aged 6 to 23 months in rural Nanchong city,Sichuan province,and to explore the relationship between dietary diversity and caregiver self-efficacy. Methods Multi-stage randomized cluster sampling method was used to select infants and young children aged 6 to 23 months and their caregivers in rural areas of Nanchong city,Sichuan province as the subjects.A structured questionnaire was designed to collect the basic information of the subjects,dietary diversity,and caregiver self-efficacy for complementary feeding.Multivariate Logistic regression was adopted to analyze the relationship between the dietary diversity and caregiver self-efficacy for complementary feeding of infants and young children. Results A total of 770 pairs of infants and young children and their caregivers were included.The minimum pass rate of dietary diversity was 61.56%(474/770) for all the infants and young children and 45.00%(108/240),69.16%(287/415),and 68.70%(79/115) for the infants and young children aged 6 to 11,12 to 17,and 18 to 23 months,respectively.The results of regression analysis showed that the caregiver self-efficacy of complementary feeding was a contributing factor for qualified dietary diversity of infants and young children in the case of other confounders being controlled(OR=1.42,95%CI=1.17-1.73,P<0.001). Conclusion The dietary diversity for infants and young children in rural Nanchong city,Sichuan province needs to be improved,and caregivers with higher self-efficacy of complementary feeding are more likely to provide diversified complementary feeding for infants and young children.


Assuntos
Cuidadores , Autoeficácia , Criança , Lactente , Humanos , Pré-Escolar , Dieta , China
2.
Int J Nanomedicine ; 19: 2625-2638, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38505169

RESUMO

Purpose: Psoriasis is a chronic and recurrent inflammatory dermatitis characterized by T cell imbalance and abnormal keratinocyte proliferation. MicroRNAs (miRNAs) hold promise as therapeutic agents for this disease; however, their clinical application is hindered by poor stability and limited skin penetration. This study demonstrates the utilization of Framework Nucleic Acid (FNA) for the topical delivery of miRNAs in psoriasis treatment. Methods: By utilizing miRNA-125b as the model drug, FNA-miR-125b was synthesized via self-assembly. The successful synthesis and stability of FNA-miR-125b in bovine fetal serum (FBS) were verified through gel electrophoresis. Subsequently, flow cytometry was employed to investigate the cell internalization on HaCaT cells, while qPCR determined the effects of FNA-miR-125b on cellular functions. Additionally, the skin penetration ability of FNA-miR-125b was assessed. Finally, a topical administration study involving FNA-miR-125b cream on imiquimod (IMQ)-induced psoriasis mice was conducted to evaluate its therapeutic efficacy. Results: The FNA-miR-125b exhibited excellent stability, efficient cellular internalization, and potent inhibition of keratinocyte proliferation. In the psoriasis mouse model, FNA-miR-125b effectively penetrated the skin tissue, resulting in reduced epidermal thickness and PASI score, as well as decreased levels of inflammatory cytokines.


Assuntos
MicroRNAs , Psoríase , Animais , Bovinos , Camundongos , MicroRNAs/genética , Queratinócitos , Pele , Psoríase/tratamento farmacológico , Psoríase/induzido quimicamente , Imiquimode/uso terapêutico , Modelos Animais de Doenças , Camundongos Endogâmicos BALB C
3.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 45(4): 541-548, 2023 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-37654134

RESUMO

Objective To investigate the status of exclusive breastfeeding and bottle feeding in remote rural areas of Sichuan province and explore the relationship between negative emotions of mothers and feeding patterns of infants.Methods Multistage cluster sampling was employed to select the infants aged 0-6 months and their mothers in remote rural areas of Sichuan province.A self-designed questionnaire was used to collect the demographic characteristics of mothers and infants and the basic family information.The Chinese version of Depression Anxiety Stress scale was used to evaluate mothers' negative emotions,and the Breastfeeding Self-efficacy scale to assess the confidence level of mothers' behavior of adhering to exclusive breastfeeding.Results Totally 723 pairs of infants and their mothers were included.The exclusive breastfeeding and bottle feeding rates were 34.16% (247/723) and 57.54% (416/723),respectively.Mothers with depression tendency were less likely to adopt exclusive breastfeeding (OR=0.532,95%CI=0.291-0.974,P=0.041) and more likely to adopt bottle feeding (OR=1.877,95%CI=1.054-3.344,P=0.033).Further subgroup analysis of breastfeeding self-efficacy showed that in the group of low self-efficacy,the mothers with depression tendency were less likely to adopt exclusive breastfeeding (OR=0.461,95%CI=0.236-0.902,P=0.024) and more likely to adopt bottle feeding (OR=1.968,95%CI=1.047-3.701,P=0.036) than the mothers without depression tendency.In the group of high self-efficacy,mothers' depression,anxiety,and stress tendency had no significant correlation with infant feeding patterns (all P>0.05).Conclusions The mothers in the remote rural areas of Sichuan province are more likely to employ bottle feeding than exclusive breastfeeding.The mothers with stronger depression tendency demonstrate lower possibility of exclusive breastfeeding and higher possibility of bottle feeding.Breastfeeding self-efficacy may affect the association between maternal depression and infant feeding patterns.


Assuntos
Ansiedade , Depressão , Comportamento Alimentar , Mães , Humanos , Lactente , China , Autoeficácia , População do Leste Asiático , Mães/psicologia , Depressão/epidemiologia
4.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 45(2): 193-199, 2023 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-37157064

RESUMO

Objective To understand the current situation and explore the influencing factors of delay in seeking medical treatment for common symptoms of residents in the rural areas of Sichuan province. Methods In July 2019,multi-stage random sampling was carried out in Zigong city,Sichuan province,and the data were collected by face-to-face questionnaire interview.The residents who had lived at hometown for more than half a year in the past year and had seen a doctor in the most recent month were surveyed.Logistic regression was adopted to predict the influencing factors of delay in seeking medical treatment. Results A total of 342 subjects were enrolled,and the incidence of delay in seeking medical treatment was 13.45%(46/342).Compared with the young and middle-aged(<65 years)people,the elderly(≥65 years)people were more likely to have delay in seeking medical treatment (OR=2.187,95%CI=1.074-4.457,P=0.031).The rural residents who gave higher score of the overall quality of township health centers were less likely to have delay in seeking medical treatment (OR=0.854,95%CI=0.735-0.992,P=0.039). Conclusions The occurrence of delay in seeking medical treatment for common symptoms of rural residents in Sichuan province is low.Age and the overall quality evaluation of township health centers affect the occurrence of delay in medical treatment among the rural residents in Sichuan province.Efforts should be made to improve the awareness of disease prevention among the elderly in rural areas.The investment in health resources in township health centers should be increased to strengthen the introduction and training of talents.These measures can improve the health services in township health centers,guide residents to make timely use of health resources,and reduce the occurrence of delay in seeking medical treatment.


Assuntos
População Rural , Pessoa de Meia-Idade , Idoso , Humanos , Inquéritos e Questionários , Modelos Logísticos , China/epidemiologia
5.
Clin Transl Gastroenterol ; 14(1): e00557, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36520782

RESUMO

INTRODUCTION: Interval colorectal cancer identified before the next surveillance colonoscopy was more likely to be located in the proximal colon. This study aimed to determine whether a second examination of the proximal colon could increase the adenoma detection rate (ADR). METHODS: Patients undergoing colonoscopy for any indications were recruited for the study. After the colonoscopy was completed with the first standard forward view examination of the proximal colon, patients were randomized to either the intervention group, in which the proximal colon was once again inspected, or the control group, in which the proximal colon was inspected once. The primary outcome was the proximal colon ADR. RESULTS: A total of 840 patients were enrolled for intention-to-treat analysis (intervention group, n = 420; control group, n = 420). The proximal colon ADR in the intervention group was significantly higher than that in the control group (35.7% vs 25.2%, P = 0.001). The whole-colon ADR was also higher in the intervention group than in the control group (44.0% vs 34.0%, P = 0.003). The higher ADR in the intervention group was also confirmed by the per-protocol analysis. Older age, adenoma detected on the first proximal colon examination, and longer total proximal colon withdrawal time were independent factors for detecting ≥1 adenoma on the second withdrawal from the proximal colon. DISCUSSION: The second examination of the proximal colon significantly increased the proximal colon ADR and whole-colon ADR in patients undergoing colonoscopy for any indication.


Assuntos
Adenoma , Neoplasias do Colo , Humanos , Estudos Prospectivos , Neoplasias do Colo/diagnóstico , Colonoscopia/métodos , Adenoma/diagnóstico
6.
Asian J Pharm Sci ; 17(3): 425-434, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35782329

RESUMO

Resorption and loss of alveolar bone leads to oral dysfunction and loss of natural or implant teeth. Biomimetic delivery of growth factors based on stem cell recruitment and osteogenic differentiation, as the key steps in natural alveolar bone regenerative process, has been an area of intense research in recent years. A mesoporous self-healing hydrogel (DFH) with basic fibroblast growth factor (bFGF) entrapment and transforming growth factor ß3 (TGFß3) - loaded chitosan microspheres (CMs) was developed. The formulation was optimized by multiple tests of self-healing, in-bottle inversion, SEM, rheological, swelling rate and in vitro degradation. In vitro tubule formation assays, cell migration assays, and osteogenic differentiation assays confirmed the ability of DFH to promote blood vessels, recruit stem cells, and promote osteogenic differentiation. The optimum DFH formula is 0.05 ml 4Arm-PEG-DF (20%) added to 1 ml CsGlu (2%) containing bFGF (80 ng) and TGFß3-microspheres (5 mg). The results of in vitro release studied by Elisa kit, indicated an 95% release of bFGF in 7 d and long-term sustained release of TGFß3. For alveolar defects rat models, the expression levels of CD29 and CD45, the bone volume fraction, trabecular number, and trabecular thickness of new bone monitored by Micro-CT in DFH treatment groups were significantly higher than others (*P < 0.05, vs Model). HE and Masson staining show the same results. In conclusion, DFH is a design of bionic alveolar remodelling microenvironment, that is in early time microvessels formed by bFGF provide nutritious to recruited endogenous stem cells, then TGFß3 slowly released speed up the process of new bones formation to common facilitate rat alveolar defect repair. The DFH with higher regenerative efficiency dovetails nicely with great demand due to the requirement of complicated biological processes.

7.
J Pharmacol Sci ; 147(2): 184-191, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34384566

RESUMO

Polygala japonica Houtt. (PJ), a member of the Polygala L. family that is suggested to exhibit detoxification properties in traditional Chinese medicine, is often used to treat upper respiratory tract infections. The anti-inflammatory effects of four main components of PJ (POL, PS-XLIX, PS-E, and PS-F) were examined using the LPS(0.3 µg·mL-1)-stimulated RAW264.7 macrophage model. The levels of NO, ROS, and iNOS were examined to analyze the anti-inflammatory activity of POL. Additionally, the levels of extracellular inflammation-related cytokines and chemokines were measured using quantibody array. The KEGG pathway analysis was performed to examine the anti-inflammatory mechanism of POL. The levels of NO in the POL-pretreated group were significantly downregulated when compared with those in the PS-E-pretreated, PS-F-pretreated, and PS-XLIX-pretreated groups. POL significantly inhibited the changes of iNOS, ROS, and inflammatory factors caused by LPS stimulation (p < 0.001). The expression levels of IL21 and GM-CSF were examined using qPCR, while those of JAK-STAT signaling pathway-related proteins in the LPS-stimulated RAW264.7 macrophages were analyzed using western blotting. POL significantly downregulated the expression of IL-21 and GM-CSF. The anti-inflammatory mechanism of POL is mediated through the JAK-STAT pathway. Thus, this study demonstrated that POL is an anti-inflammatory component of PJ and elucidated its mechanism.


Assuntos
Anti-Inflamatórios , Medicamentos de Ervas Chinesas/farmacologia , Glicosídeos/farmacologia , Inflamação/genética , Polygala/química , Xantonas/farmacologia , Animais , Citocinas/genética , Citocinas/metabolismo , Regulação para Baixo/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Inflamação/etiologia , Mediadores da Inflamação/metabolismo , Interleucinas/genética , Interleucinas/metabolismo , Lipopolissacarídeos/efeitos adversos , Camundongos , Óxido Nítrico/genética , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Células RAW 264.7 , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos
8.
Clin Cosmet Investig Dermatol ; 14: 655-664, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34163204

RESUMO

BACKGROUND: Sensitive skin (SS) is easily irritated by various environmental stimuli, and epidemiological surveys surprisingly find that self-perceived SS is widespread worldwide. OBJECTIVE: To investigate whether SS is linked to changes in the skin bacterial population using 16S rRNA sequencing and bioinformatic analysis. PATIENTS AND METHODS: According to both the Huaxi SS Questionnaire and Lactic Acid Stimulation Test, 60 female volunteers in Guangzhou were classified into normal skin (NS) and SS groups. Skin barrier parameters were assessed by the CK skin tester. The DNA of the bacterial flora on the facial skin surface was extracted and was subjected to 16S rRNA sequencing. RESULTS: The skin hydration was significantly lower in the SS group compared to the NS group (P =0.032). Based on 16S rRNA sequencing and bioinformatic analysis, the number of operational taxonomic units (OTUs) significantly decreased in the SS group (P =0.0235, SS vs NS). The relative abundance of Neisseriaceae in SS group decreased significantly (P <0.05, SS vs NS), while that of Neisseria (within the Neisseriaceae family) increased significantly (P <0.05, SS vs NS). CONCLUSION: SS is accompanied by a decrease in species diversity and richness, which may be relevant to the weakening of the microbial barrier (due to the increase of Neisseria or the decrease of Neisseriaceae). Thus, corresponding treatment for Neisseriaceae may be a new idea in the treatment of SS.

9.
Exploration (Beijing) ; 1(3): 20210109, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37323692

RESUMO

Microneedles (MNs) offer a simple and minimally invasive way to sample skin interstitial fluid for bioanalysis. Through the integration with portable or wearable sensing devices, it allows us to get qualitative information about some biomarkers in situ. This work is to show a MN platform with open groove channels that are manufactured using photopolymerization 3D printing. The grooves on the needle surface permit that liquid flows from the tips to the base under the influence of capillary force. The ultimate MN device can penetrate skin and tissues and sample liquid in the skin model. By taking the glucose as the model biomarker, we demonstrate that the biomarkers in the extracted liquid can be analyzed in situ by the commercial test strips attached to the back.

10.
J Med Chem ; 62(7): 3503-3512, 2019 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-30856324

RESUMO

Identification of novel chemotypes with antimalarial efficacy is imperative to combat the rise of Plasmodium species resistant to current antimalarial drugs. We have used a hybrid target-phenotype approach to identify and evaluate novel chemotypes for malaria. In our search for drug-like aspartic protease inhibitors in publicly available phenotypic antimalarial databases, we identified GNF-Pf-4691, a 4-aryl- N-benzylpyrrolidine-3-carboxamide, as having a structure reminiscent of known inhibitors of aspartic proteases. Extensive profiling of the two terminal aryl rings revealed a structure-activity relationship in which relatively few substituents are tolerated at the benzylic position, but the 3-aryl position tolerates a range of hydrophobic groups and some heterocycles. Out of this effort, we identified (+)-54b (CWHM-1008) as a lead compound. 54b has EC50 values of 46 and 21 nM against drug-sensitive Plasmodium falciparum 3D7 and drug-resistant Dd2 strains, respectively. Furthermore, 54b has a long half-life in mice (4.4 h) and is orally efficacious in a mouse model of malaria (qd; ED99 ∼ 30 mg/kg/day). Thus, the 4-aryl- N-benzylpyrrolidine-3-carboxamide chemotype is a promising novel chemotype for malaria drug discovery.


Assuntos
Antimaláricos/farmacologia , Pirrolidinas/farmacologia , Administração Oral , Animais , Antimaláricos/administração & dosagem , Antimaláricos/química , Disponibilidade Biológica , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Malária/tratamento farmacológico , Camundongos , Microssomos Hepáticos/efeitos dos fármacos , Pirrolidinas/administração & dosagem , Pirrolidinas/química , Relação Estrutura-Atividade
11.
Pediatr Neonatol ; 54(2): 88-94, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23590952

RESUMO

BACKGROUND: All-trans retinoic acid (ATRA) induces in vitro angiogenesis and vascular endothelial growth factor (VEGF) secretion. Prenatal administration of vitamin A tends to increase the pulmonary and plasma levels of VEGF in the developing mouse. The aims of this study were to examine the effects of maternal retinoic acid treatment on lung VEGF expression and angiogenesis in oligohydramnios-exposed fetal rats. METHODS: On day 16 of gestation, pregnant Sprague-Dawley rats were randomly assigned to either the retinoic acid group (intragastric ATRA at 10 mg/kg body weight) or the vehicle group. We punctured each uterine sac to produce oligohydramnios, and fetuses in the opposite uterine horn served as controls. On day 21 of gestation, the fetuses were delivered by cesarean section. RESULTS: Rats exposed to oligohydramnios exhibited lower lung weights and lung/body weight ratios, and ATRA exhibited no effects on the body or lung weights of oligohydramnios-exposed rats. Lung microvessel density decreased in oligohydramnios-exposed rats of maternal vehicle-treated dams. Microvessel density was comparable between the oligohydramnios + retinoic acid group and the control + retinoic acid group. VEGF expression was comparable among control and oligohydramnios-exposed rats of maternal vehicle- or retinoic acid-treated dams. CONCLUSION: Maternal retinoic acid treatment did not increase lung VEGF expression or enhance lung development in oligohydramnios-exposed fetal rats. These results do not support the use of maternal retinoic acid to prevent oligohydramnios-induced pulmonary hypoplasia in the pseudoglandular stage.


Assuntos
Pulmão/embriologia , Neovascularização Fisiológica/efeitos dos fármacos , Oligo-Hidrâmnio/fisiopatologia , Tretinoína/farmacologia , Animais , Feminino , Pulmão/metabolismo , Oligo-Hidrâmnio/tratamento farmacológico , Gravidez , Ratos , Ratos Sprague-Dawley , Fator A de Crescimento do Endotélio Vascular/análise , Fator A de Crescimento do Endotélio Vascular/genética
12.
J Med Chem ; 56(3): 879-94, 2013 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-23301703

RESUMO

Bcr-Abl(T315I) mutation-induced imatinib resistance remains a major challenge for clinical management of chronic myelogenous leukemia (CML). Herein, we report GZD824 (10a) as a novel orally bioavailable inhibitor against a broad spectrum of Bcr-Abl mutants including T315I. It tightly bound to Bcr-Abl(WT) and Bcr-Abl(T315I) with K(d) values of 0.32 and 0.71 nM, respectively, and strongly inhibited the kinase functions with nanomolar IC(50) values. The compound potently suppressed proliferation of Bcr-Abl-positive K562 and Ku812 human CML cells with IC(50) values of 0.2 and 0.13 nM, respectively. It also displayed good oral bioavailability (48.7%), a reasonable half-life (10.6 h), and promising in vivo antitumor efficacy. It induced tumor regression in mouse xenograft tumor models driven by Bcr-Abl(WT) or the mutants and significantly improved the survival of mice bearing an allograft leukemia model with Ba/F3 cells harboring Bcr-Abl(T315I). GZD824 represents a promising lead candidate for development of Bcr-Abl inhibitors to overcome acquired imatinib resistance.


Assuntos
Antineoplásicos/farmacologia , Benzamidas/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Proteínas de Fusão bcr-abl/antagonistas & inibidores , Mutação , Piperazinas/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Pirazóis/farmacologia , Pirimidinas/farmacologia , Administração Oral , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacocinética , Benzamidas/administração & dosagem , Benzamidas/farmacocinética , Disponibilidade Biológica , Linhagem Celular Tumoral , Proteínas de Fusão bcr-abl/metabolismo , Humanos , Mesilato de Imatinib , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Fosforilação , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/farmacocinética , Proteínas Tirosina Quinases/metabolismo , Pirazóis/administração & dosagem , Pirazóis/farmacocinética , Espectrometria de Massas por Ionização por Electrospray
13.
J Med Chem ; 55(22): 10033-46, 2012 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-23088644

RESUMO

A series of 3-(1H-1,2,3-triazol-1-yl)benzamide derivatives were designed and synthesized as new Bcr-Abl inhibitors by using combinational strategies of bioisosteric replacement, scaffold hopping, and conformational constraint. The compounds displayed significant inhibition against a broad spectrum of Bcr-Abl mutants including the gatekeeper T315I and p-loop mutations, which are associated with disease progression in CML. The most potent compounds 6q and 6qo strongly inhibited the kinase activities of Bcr-Abl(WT) and Bcr-Abl(T315I) with IC(50) values of 0.60, 0.36 and 1.12, 0.98 nM, respectively. They also potently suppressed the proliferation of K562, KU812 human CML cells, and a panel of murine Ba/F3 cells ectopically expressing either Bcr-Abl(WT) or any of a panel of other Bcr-Abl mutants that have been shown to contribute to clinical acquired resistance, including Bcr-Abl(T315I), with IC(50) values in low nanomolar ranges. These compounds may serve as lead compounds for further development of new Bcr-Abl inhibitors capable of overcoming clinical acquired resistance against imatinib.


Assuntos
Benzamidas/farmacologia , Desenho de Fármacos , Proteínas de Fusão bcr-abl/antagonistas & inibidores , Isoleucina/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Mutação/genética , Treonina/genética , Benzamidas/química , Western Blotting , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Proteínas de Fusão bcr-abl/genética , Humanos , Mesilato de Imatinib , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Modelos Moleculares , Estrutura Molecular , Fosforilação , Piperazinas/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêutico , Pirimidinas/uso terapêutico , Relação Estrutura-Atividade
14.
Acta Pharmacol Sin ; 33(8): 991-7, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22796762

RESUMO

AIM: To test the hypothesis that the tissue plasminogen activator (tPA) may counteract the inhibitory effect of plasminogen activator inhibitors (PAI) and attenuate lung injury in a rat model of ventilator-induced lung injury (VILI). METHODS: Adult male Sprague-Dawley rats were ventilated with a HVZP (high-volume zero PEEP) protocol for 2 h at a tidal volume of 30 mL/kg, a respiratory rate of 25 breaths/min, and an inspired oxygen fraction of 21%. The rats were divided into 3 groups (n=7 for each): HVZP+tPA group receiving tPA (1.25 mg/kg, iv) 15 min before ventilation, HVZP group receiving HVZP+vehicle injection, and a control group receiving no ventilation. After 2 h of ventilation, the rats were killed; blood and lungs were collected for biochemical and histological analyses. RESULTS: HVZP ventilation significantly increased total protein content and the concentration of macrophage inflammatory protein-2 (MIP-2) in the bronchoalveolar lavage fluid (BALF) as well as the lung injury score. Rats that received HVZP ventilation had significantly higher lung PAI-1 mRNA expression, plasma PAI-1 and plasma D-dimer levels than the control animals. tPA treatment significantly reduced the BALF total protein and the lung injury score as compared to the HVZP group. tPA treatment also significantly decreased the plasma D-dimer levels and the HVZP ventilation-induced lung vascular fibrin thrombi. tPA treatment showed no effect on MIP-2 level in BALF. CONCLUSION: These results demonstrate that VILI increases lung PAI-1 mRNA expression, plasma levels of PAI-1 and D-dimers, lung injury score and vascular fibrin deposition. tPA can attenuate VILI by decreasing capillary-alveolar protein leakage as well as local and systemic coagulation as shown by decreased lung vascular fibrin deposition and plasma D-dimers.


Assuntos
Ativador de Plasminogênio Tecidual/uso terapêutico , Lesão Pulmonar Induzida por Ventilação Mecânica/patologia , Lesão Pulmonar Induzida por Ventilação Mecânica/prevenção & controle , Animais , Masculino , Ratos , Ratos Sprague-Dawley , Volume de Ventilação Pulmonar/efeitos dos fármacos , Volume de Ventilação Pulmonar/fisiologia , Ativador de Plasminogênio Tecidual/farmacologia , Lesão Pulmonar Induzida por Ventilação Mecânica/fisiopatologia
15.
J Pharmacol Exp Ther ; 340(1): 169-75, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22005041

RESUMO

Bronchopulmonary dysplasia (BPD) remains a major cause of morbidity and mortality during the first year of life, and many infants have significant respiratory problems throughout childhood. Currently no effective therapy is clinically available to prevent the long-term pulmonary sequelae of BPD. Previous research has demonstrated that the renin-angiotensin system is up-regulated in human lung fibroblasts. Angiotensin II type 1 receptor (AT1R) antagonists and AT1R short interfering RNA diminished hyperoxia-increased collagen expression, whereas AT2R antagonists did not have any effects on these hyperoxia-induced changes. The in vivo therapeutic effects of AT1R antagonists on hyperoxia-induced lung fibrosis remain unknown. The present study assessed the effects of an AT1R antagonist (losartan) on preventing hyperoxia-induced lung fibrosis in newborn rats. Rat pups were exposed to 7 days of > 95% O2 and an additional 2 weeks of 60% O2. AT1R antagonist-treated pups were injected intraperitoneally with losartan at a dose of 10 mg/kg/day from postnatal days 1 to 7 and a dose of 5 mg/kg/day from postnatal days 8 to 21. Control group pups were injected with an equal volume of normal saline. AT1R antagonist treatment attenuated the hyperoxia-induced lung fibrosis on postnatal days 7 and 21 and also decreased the hyperoxia-induced expression of extracellular signal-regulated protein kinase and α-smooth muscle actin. AT1R antagonist treatment did not affect body weight or lung weight of the rats. These data suggest that AT1R antagonist may offer a novel therapeutic strategy for preventing hyperoxia-induced lung fibrosis.


Assuntos
Bloqueadores do Receptor Tipo 1 de Angiotensina II/uso terapêutico , Hiperóxia/complicações , Fibrose Pulmonar/tratamento farmacológico , Actinas/biossíntese , Animais , Animais Recém-Nascidos , Western Blotting , Peso Corporal/efeitos dos fármacos , Colágeno/biossíntese , Colágeno/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/biossíntese , Feminino , Hiperóxia/patologia , Losartan/farmacologia , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Pulmão/patologia , Tamanho do Órgão/efeitos dos fármacos , Gravidez , Fibrose Pulmonar/etiologia , Fibrose Pulmonar/patologia , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo Real
16.
Neonatology ; 101(1): 47-54, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-21791939

RESUMO

BACKGROUND: Oxygen toxicity plays an important role in lung injury and may lead to bronchopulmonary dysplasia. We previously demonstrated that hyperoxia activated the renin-angiotensin system (RAS) in cultured human fetal lung fibroblasts. OBJECTIVE: To examine whether the upregulation of RAS components is associated with hyperoxia-induced lung fibrosis in neonatal Sprague-Dawley rats. METHODS: Experimental rat pups were exposed to 1 week of >95% O(2) and a further 2 weeks of 60% O(2). Control pups were exposed to room air over the same periods. Lung tissues were taken for biochemical and histochemical assays on postnatal days 7 and 21. RESULTS: Hyperoxia significantly increased total collagen content and the expression of type I collagen and alpha smooth muscle actin when compared to control rats. RAS components including angiotensinogen, angiotensin-converting enzyme, angiotensin II, and angiotensin II type 1 receptor were significantly upregulated by hyperoxia. The results also demonstrated that only the extracellular signal-regulated kinase (ERK) signaling pathway was activated by hyperoxia exposure. p38 mitogen-activated protein kinase and c-Jun N-terminal kinase were not activated. CONCLUSIONS: Local RAS activation is involved in the pathogenesis of hyperoxia-induced lung fibrosis in neonatal rats. ERK phosphorylation might mediate angiotensin II type 1 receptor activation.


Assuntos
Hiperóxia/induzido quimicamente , Oxigênio/efeitos adversos , Fibrose Pulmonar/induzido quimicamente , Sistema Renina-Angiotensina/fisiologia , Angiotensina II/genética , Angiotensina II/metabolismo , Animais , Animais Recém-Nascidos , Biomarcadores/metabolismo , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Modelos Animais de Doenças , Regulação da Expressão Gênica no Desenvolvimento , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Pulmão/patologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/genética , Fibrose Pulmonar/metabolismo , Fibrose Pulmonar/patologia , Ratos , Ratos Sprague-Dawley , Receptor Tipo 1 de Angiotensina/genética , Receptor Tipo 1 de Angiotensina/metabolismo , Receptor Tipo 2 de Angiotensina/genética , Receptor Tipo 2 de Angiotensina/metabolismo
17.
Pediatr Neonatol ; 52(1): 5-10, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21385650

RESUMO

BACKGROUND: Airway remodeling refers to the structural changes in the airways of asthma. Caveolin-1 reduces cell growth and negatively regulates smooth muscle cell proliferation. The aim was to investigate lung caveolin-1 status in a murine model of acute allergic airway disease. METHODS: Six- to eight-week-old female BALB/c mice were sensitized by intraperitoneal injections of phosphate-buffered saline or ovalbumin (OVA) and aluminium hydroxide on Days 0 and 14, challenged with aerosolized saline or OVA (1%) on Days 21-25, 28-32, and 35. The mice were killed 1 day after the last OVA/saline challenge. Serum OVA-specific immunoglobulin E (IgE) was measured by enzyme-linked immunosorbent assay. Peribronchial inflammation was quantified by morphometric analysis. Lung caveolin-1 and Type I collagen mRNA expression was determined by real-time reverse-transcription polymerase chain reaction. Total lung collagen was measured using Sircol Assay Kit. RESULTS: Serum OVA-specific IgE levels were significantly elevated in OVA-challenged mice when compared with saline-challenged mice. Percentage of inflammatory cells in the bronchoalveolar lavage was significantly higher in the OVA-challenged animals. The animals' lungs that were sensitized and challenged with OVA contained large numbers of inflammatory cells concentrated near the airways and in the perivascular areas. The thickness of the bronchial epithelial layer and smooth muscle layer and the numbers of total inflammatory cells and eosinophils significantly increased in OVA-challenged mice. Caveolin-1 mRNA expression significantly decreased and Type I collagen mRNA expression significantly increased in the lung tissue of OVA-challenged mice. CONCLUSION: These results suggest that caveolin-1 seems to be involved in the pathogenesis of airway remodeling of acute allergic airway disease.


Assuntos
Asma/metabolismo , Caveolina 1/metabolismo , Doença Aguda , Remodelação das Vias Aéreas , Animais , Biomarcadores/metabolismo , Lavagem Broncoalveolar , Colágeno/metabolismo , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Reação em Cadeia da Polimerase Via Transcriptase Reversa
18.
Artigo em Inglês | MEDLINE | ID: mdl-19584080

RESUMO

Baicalin is a flavonoid compound purified from the medicinal plant Scutellaria baicalensis Georgi and has been reported to stimulate surfactant protein (SP)-A gene expression in human lung epithelial cell lines (H441). The aims of this study were to determine whether maternal baicalin treatment could increase lung surfactant production and induce lung maturation in fetal rats. This study was performed with timed pregnant Sprague-Dawley rats. One-day baicalin group mothers were injected intraperitoneally with baicalin (5 mg/kg/day) on Day 18 of gestation. Two-day baicalin group mothers were injected intraperitoneally with baicalin (5 mg/kg/day) on Days 17 and 18 of gestation. Control group mothers were injected with vehicle alone on Day 18 of gestation. On Day 19 of gestation, fetuses were delivered by cesarean section. Maternal treatment with 2-day baicalin significantly increased saturated phospholipid when compared with control group and total phospholipid in fetal lung tissue when compared with control and 1-day baicalin groups. Antenatal treatment with 2-day baicalin significantly increased maternal growth hormone when compared with control group. Fetal lung SP-A mRNA expression and maternal serum corticosterone levels were comparable among the three experimental groups. Maternal baicalin treatment increases pulmonary surfactant phospholipids of fetal rat lungs and the improvement was associated with increased maternal serum growth hormone. These results suggest that antenatal baicalin treatment might accelerate fetal rat lung maturation.

19.
Free Radic Biol Med ; 49(1): 88-95, 2010 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-20353822

RESUMO

A high concentration of oxygen can cause lung injury and lead to pulmonary fibrosis. Angiotensin (Ang) II induces human lung fibroblast proliferation and stimulates collagen synthesis. However, the role of the renin-angiotensin system (RAS) in the pathogenesis of hyperoxia-induced collagen production is unclear. The aims of this study were to investigate the effects of hyperoxia on the components of the RAS and collagen expression in human lung fibroblasts (MRC-5). Hyperoxia increased total collagen, collagen type I, and alpha-smooth muscle actin (alpha-SMA) mRNA and protein expression. RAS components and Ang II production were also significantly increased after hyperoxic exposure. Hyperoxia induced Ang II type 1 receptor (AT1R) expression but did not alter AT2R expression, furthermore, silencing of AT1R signaling with small interfering RNA suppressed hyperoxia-induced phosphorylated-ERK (p-ERK) 1/2, alpha-SMA, and collagen type I expression. Ang II increased p-ERK 1/2 and collagen type I expression, and these increases were inhibited by the AT1R inhibitor, losartan, but not by the AT2R inhibitor, PD123319 under both normoxic and hyperoxic conditions. These data suggest Ang II-mediated signaling transduction via AT1R is involved in hyperoxia-induced collagen synthesis in human lung fibroblasts.


Assuntos
Actinas/metabolismo , Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Colágeno Tipo I/biossíntese , Fibroblastos/metabolismo , Receptor Tipo 1 de Angiotensina/metabolismo , Actinas/genética , Bloqueadores do Receptor Tipo 2 de Angiotensina II , Células Cultivadas , Colágeno Tipo I/genética , Fibroblastos/efeitos dos fármacos , Fibroblastos/patologia , Humanos , Hiperóxia , Imidazóis/farmacologia , Losartan/farmacologia , Pulmão/patologia , Piridinas/farmacologia , RNA Interferente Pequeno/genética , Receptor Tipo 1 de Angiotensina/genética , Sistema Renina-Angiotensina/efeitos dos fármacos , Sistema Renina-Angiotensina/genética , Transdução de Sinais
20.
Respiration ; 80(3): 246-53, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20110652

RESUMO

BACKGROUND: Mechanical ventilation with a high tidal volume (VT) increases lung and systemic plasminogen activator inhibitor (PAI)-1 levels and alveolar fibrin deposition. Activated protein C (APC) may decrease PAI activity in endothelial cell-conditioned medium and thus enhance fibrinolysis. OBJECTIVES: The aims of this study were to test the hypothesis that APC can neutralize PAI-1 activity and improve lung function in an animal model of ventilator-induced lung injury. METHODS: Rats were ventilated with a high-volume zero positive end-expiratory pressure (PEEP; HVZP) protocol by a volume-cycled ventilator for 2 h at a VT of 30 ml/kg, a respiratory rate of 25 breaths/min, and an FiO(2) of 0.21. Fifteen minutes before ventilation, the rats received intravenous APC (250 microg/kg, HVZP+APC group) or normal saline (vehicle; HVZP group). Another group that received no ventilation served as the control group. RESULTS: Levels of arterial blood gas tension were comparable between the two ventilation groups throughout the study period. Rats treated with the HVZP protocol exhibited significantly higher total protein and macrophage inflammatory protein-2 concentrations in bronchoalveolar lavage fluid (BALF) and higher lung PAI-1 mRNA expression and plasma active PAI-1 levels than did the control group. Administration of APC tended to reduce the BALF protein content and systemic PAI-1 activity but did not improve the lung histology in the HVZP+APC group. Plasma levels of D-dimers were comparable among the three study groups. CONCLUSIONS: These results suggest that APC administered at a higher dosage might improve lung function by reducing alveolar protein leakage and systemic coagulation.


Assuntos
Fibrinólise/efeitos dos fármacos , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Proteína C/uso terapêutico , Lesão Pulmonar Induzida por Ventilação Mecânica/prevenção & controle , Animais , Líquido da Lavagem Broncoalveolar/química , Quimiocina CXCL2/metabolismo , Produtos de Degradação da Fibrina e do Fibrinogênio/metabolismo , Imuno-Histoquímica , Pulmão/patologia , Masculino , Proteína C/farmacologia , Troca Gasosa Pulmonar , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Volume de Ventilação Pulmonar , Lesão Pulmonar Induzida por Ventilação Mecânica/metabolismo , Lesão Pulmonar Induzida por Ventilação Mecânica/patologia
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