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1.
J Allergy Clin Immunol ; 153(1): 173-181.e10, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37815782

RESUMO

BACKGROUND: Prior studies of peanut sublingual immunotherapy (SLIT) have suggested a potential advantage with younger age at treatment initiation. OBJECTIVE: We studied the safety and efficacy of SLIT for peanut allergy in 1- to 4-year-old children. METHODS: Peanut-allergic 1- to 4-year-old children were randomized to receive 4 mg peanut SLIT versus placebo. Desensitization was assessed by double-blind, placebo-controlled food challenge (DBPCFC) after 36 months of treatment. Participants desensitized to at least 443 mg peanut protein discontinued therapy for 3 months and then underwent DBPCFC to assess for remission. Biomarkers were measured at baseline and longitudinally during treatment. RESULTS: Fifty participants (25 peanut SLIT, 25 placebo) with a median age of 2.4 years were enrolled across 2 sites. The primary end point of desensitization was met with actively treated versus placebo participants having a significantly greater median cumulative tolerated dose (4443 mg vs 143 mg), higher likelihood of passing the month 36 DBPCFC (60% vs 0), and higher likelihood of demonstrating remission (48% vs 0). The highest rate of desensitization and remission was seen in 1- to 2-year-olds, followed by 2- to 3-year-olds and 3- to 4-year-olds. Longitudinal changes in peanut skin prick testing, peanut-specific IgG4, and peanut-specific IgG4/IgE ratio were seen in peanut SLIT but not placebo participants. Oropharyngeal itching was more commonly reported by peanut SLIT than placebo participants. Skin, gastrointestinal, upper respiratory, lower respiratory, and multisystem adverse events were similar between treatment groups. CONCLUSION: Peanut SLIT safely induces desensitization and remission in 1- to 4-year-old children, with improved outcomes seen with younger age at initiation.


Assuntos
Hipersensibilidade a Amendoim , Imunoterapia Sublingual , Humanos , Pré-Escolar , Lactente , Arachis , Dessensibilização Imunológica/efeitos adversos , Administração Sublingual , Hipersensibilidade a Amendoim/terapia , Hipersensibilidade a Amendoim/etiologia , Alérgenos , Método Duplo-Cego , Imunoglobulina G , Administração Oral
2.
J Allergy Clin Immunol ; 151(6): 1558-1565.e6, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36828080

RESUMO

BACKGROUND: Studies on the efficacy of peanut sublingual immunotherapy (SLIT) are limited. The durability of desensitization after SLIT has not been well described. OBJECTIVE: We sought to evaluate the efficacy and safety of 4-mg peanut SLIT and persistence of desensitization after SLIT discontinuation. METHODS: Challenge-proven peanut-allergic 1- to 11-year-old children were treated with open-label 4-mg peanut SLIT for 48 months. Desensitization after peanut SLIT was assessed by a 5000-mg double-blind, placebo-controlled food challenge (DBPCFC). A novel randomly assigned avoidance period of 1 to 17 weeks was followed by the DBPCFC. Skin prick test results immunoglobulin levels, basophil activation test results, TH1, TH2, and IL-10 cytokines were measured longitudinally. Safety was assessed through patient-reported home diaries. RESULTS: Fifty-four participants were enrolled and 47 (87%) completed peanut SLIT and the 48-month DBPCFC per protocol. The mean successfully consumed dose (SCD) during the DBPCFC increased from 48 to 2723 mg of peanut protein after SLIT (P < .0001), with 70% achieving clinically significant desensitization (SCD > 800 mg) and 36% achieving full desensitization (SCD = 5000 mg). Modeled median time to loss of clinically significant desensitization was 22 weeks. Peanut skin prick test; peanut-specific IgE, IgG4, and IgG4/IgE ratio; and peanut-stimulated basophil activation test, IL-4, IL-5, IL-13, IFN-γ, and IL-10 changed significantly compared with baseline, with changes seen as early as 6 months. Median rate of reaction per dose was 0.5%, with transient oropharyngeal itching being the most common, and there were no dosing symptoms requiring epinephrine. CONCLUSIONS: In this open-label, prospective study, peanut SLIT was safe and induced clinically significant desensitization in most of the children, lasting more than 17 weeks after discontinuation of therapy.


Assuntos
Hipersensibilidade a Amendoim , Imunoterapia Sublingual , Humanos , Criança , Lactente , Pré-Escolar , Imunoterapia Sublingual/efeitos adversos , Imunoterapia Sublingual/métodos , Arachis , Dessensibilização Imunológica/efeitos adversos , Dessensibilização Imunológica/métodos , Interleucina-10 , Estudos Prospectivos , Hipersensibilidade a Amendoim/terapia , Hipersensibilidade a Amendoim/diagnóstico , Imunoglobulina E , Alérgenos , Imunoglobulina G , Administração Oral
3.
Plant Cell Environ ; 46(3): 850-864, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36573466

RESUMO

The maintenance of a proton gradient across the thylakoid membrane is an integral aspect of photosynthesis that is mainly established by the splitting of water molecules in photosystem II and plastoquinol oxidation at the cytochrome complex, and it is necessary for the generation of ATP in the last step of photophosphorylation. Although environmental stresses, such as high temperatures, are known to disrupt this fundamental process, only a few studies have explored the molecular mechanisms underlying proton gradient regulation during stress. The present study identified a heat-sensitive mutant that displays aberrant photosynthesis at high temperatures. This mutation was mapped to AtFtsH11, which encodes an ATP-dependent AAA-family metalloprotease. We showed that AtFtsH11 localizes to the chloroplast inner envelope membrane and is capable of degrading the ATP synthase assembly factor BFA3 under heat stress. We posit that this function limits the amount of ATP synthase integrated into the thylakoid membrane to regulate proton efflux from the lumen to the stroma. Our data also suggest that AtFtsH11 is critical in stabilizing photosystem II and cytochrome complexes at high temperatures, and additional studies can further elucidate the specific molecular functions of this critical regulator of photosynthetic thermotolerance.


Assuntos
Arabidopsis , ATPases de Cloroplastos Translocadoras de Prótons , ATPases de Cloroplastos Translocadoras de Prótons/metabolismo , Complexo de Proteína do Fotossistema II/metabolismo , Prótons , Arabidopsis/genética , Arabidopsis/metabolismo , Cloroplastos/metabolismo , Fotossíntese/fisiologia , Resposta ao Choque Térmico , Trifosfato de Adenosina/metabolismo , Citocromos/metabolismo
4.
Comput Math Methods Med ; 2022: 4435722, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36277007

RESUMO

Objective: To evaluate the effect of hemp cotton sanitary pads on the vaginal microecology. Methods: A randomized controlled field trial was used to recruit 1002 community-based women of childbearing age. The women were randomly divided into experimental and control groups. The experimental group used hemp cotton sanitary pads, while the control group used two types of cotton sanitary randomly chosen from the top five sanitary pads in terms of market share in China. The vaginal microecology was compared between the two groups after three months. Results: According to the vaginal microecologic examination results at baseline, 1002 women were included in 3 groups: normal vaginal microecologic, vaginal microecological disorders, and suspected vaginal infections. The number of patients in three groups were 39 (3.9%), 652 (65.1%), and 311 (31%), respectively. Three months later, the vaginal microecologic status and vaginal pH value of the suspected vaginal infection group were not significantly different between the experimental group and control group. The experimental group outperformed the control group with respect to vaginal cleanliness and vaginal microecology status in the women without a vaginal infection (normal vaginal microecology or microecological disorders group). The rate of abnormal cleanliness in the experimental group was lower than the control group (31.95% [108/338] vs. 43.62% [154/353]). The incidence of suspected vaginitis in the experimental group was lower than the control group (15.29% [51/338] vs. 23.51% [83/353]). Conclusion: For women without vaginal inflammation, the use of hemp cotton sanitary pads during menstruation can help maintain the balance of the vaginal microecology to prevent reproductive tract infections.


Assuntos
Cannabis , Humanos , Feminino , Produtos de Higiene Menstrual , Vagina , Menstruação , China
5.
Comput Intell Neurosci ; 2022: 8008796, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35860637

RESUMO

Technology is the means by which all arts, including woodblock prints, are realized. The "kinship" with modern science and technology makes the development history of woodcut art that can also be understood as a technology history. The purpose of the texture expression produced in the creation of contemporary woodcut is to explore the rich texture expression forms made by contemporary representative painters using special material materials and tools in artistic creation, form a painting technique of personalized words, add new aesthetic meaning to art, and lay a foundation for the formation of unique style of Contemporary Art and the creation and development of woodcut texture. With the development of the times and the change of the public's aesthetic taste, the traditional pattern of printmaking needs to be properly transformed if it is to adapt to the modern humanistic environment, which also involves the importance of screen layout and pattern analysis of Chinese traditional woodcut. Based on the analysis of texture and color texture features in a few-sample environment, this paper proposes an automatic classification method for vignetting texture pictures by extracting the corresponding vignetting coefficients, and through experiments to verify that the proposed SILCO has good generalization sex. In the algorithm designed in this paper, the experiment shows that the accuracy P has a 64.7% improvement effect, and the recall r has a 67.8% performance improvement. On the whole, the experimental data show that the comprehensive classification accuracy is more than 57.4%.


Assuntos
Algoritmos , China , Cor
6.
J Allergy Clin Immunol ; 150(5): 1144-1153, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35716952

RESUMO

BACKGROUND: Oral immunotherapy (OIT) leads to suppression of mast cell and basophil degranulation along with changes in the adaptive immune response. OBJECTIVES: This study aimed to determine how rapidly these effects occur during OIT and more broadly, the kinetics of basophil and mast cell suppression throughout the course of therapy. METHODS: Twenty participants, age 4 to 12 years, were enrolled in a peanut OIT trial and assessed for desensitization and sustained unresponsiveness after 9 months of therapy. Blood was collected 5 times in the first month and then intermittently throughout to quantify immunoglobulins and assess basophil activation by CD63, CD203c, and phosphorylated SYK (pSYK). RESULTS: Twelve of 16 participants that completed the trial were desensitized after OIT, with 9 achieving sustained unresponsiveness after discontinuing OIT for 4 weeks. Basophil hyporesponsiveness, defined by lower CD63 expression, was detected as early as day 90. pSYK was correlated with CD63 expression, and there was a significant decrease in pSYK by day 250. CD203c expression remained unchanged throughout therapy. Interestingly, although basophil activation was decreased across the cohort during OIT, basophil activation did not correlate with individual clinical outcomes. Serum peanut-specific IgG4 and IgA increased throughout therapy, whereas IgE remained unchanged. CONCLUSIONS: Suppression of basophil activation occurs within the first 90 days of peanut OIT, ultimately leading to suppression of signaling through pSYK.


Assuntos
Arachis , Hipersensibilidade a Amendoim , Criança , Pré-Escolar , Humanos , Administração Oral , Alérgenos , Basófilos , Dessensibilização Imunológica , Fatores Imunológicos
7.
BMJ Open ; 12(2): e049627, 2022 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-35190413

RESUMO

OBJECTIVE: The rapid spread of COVID-19 has overwhelmed healthcare systems across the world. During the early stage of the pandemic, frontline healthcare workers (FHWs) caring for patients at intensive care units (ICUs) faced extreme pressure and challenges. This qualitative study aimed to describe the different phases of psychological distress of FHWs during the early stage of the COVID-19 pandemic. DESIGN: Qualitative study. SETTING: The First Affiliated Hospital of Zhengzhou University, a designated hospital for patients with COVID-19 in central China. PARTICIPANTS: Eight physicians and six nurses working in the ICU who provided direct patient care for COVID-19 patients. METHODS: A descriptive phenomenological study using thematic analysis was applied. Semi-structured one-on-one interviews over telephone or Wechat (a social platform in China) rather than face-to-face interviews were conducted due to quarantine. Interviews were audio-recorded and transcribed verbatim and then were analysed thematically. FINDINGS: A total of 14 interviews were conducted, and each interview lasted 20-60 min. Five thematic categories were identified, and the participants' psychological experiences were classified into five stages (1) the mobilisation period: a sense of responsibility with worries; (2) the preparation period: worries, fears and doubts about the epidemic; (3) the transitional period: complex and diverse psychological feelings; (4) the adaptation period: self-adjustment and help from external support and (5) the reflection period: a reflection on life and nature. CONCLUSION: The study showed that the COVID-19 pandemic had significant psychological impacts on FHWs. Self-regulation and external support help FHWs to overcome challenges to a certain extent. More attention should be paid to the psychological wellbeing of ICU FHWs in COVID-19-designated hospitals.


Assuntos
COVID-19 , Angústia Psicológica , China/epidemiologia , Pessoal de Saúde/psicologia , Humanos , Unidades de Terapia Intensiva , Pandemias , Pesquisa Qualitativa , SARS-CoV-2
8.
Clin Exp Allergy ; 49(2): 180-189, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30126028

RESUMO

BACKGROUND: Mechanisms underlying oral immunotherapy (OIT) are unclear and the effects on immune cells at varying maintenance doses are unknown. OBJECTIVE: We aimed to determine the immunologic changes caused by peanut OIT in preschool aged children and determine the effect on these immune responses in groups ingesting low or high-dose peanut OIT (300 mg or 3000 mg, respectively) as maintenance therapy. METHODS: Blood was drawn at several time-points throughout the OIT protocol and PBMCs isolated and cultured with peanut antigens. Secreted cytokines were quantified via multiplex assay, whereas Treg and peanut-responsive CD4 T cells were studied with flow cytometry. Basophil activation assays were also conducted. RESULTS: Th2-, Th1-, Th9- and Tr1-type cytokines decreased over the course of OIT in groups on high- and low-dose OIT. There were no significant differences detected in cytokine changes between the high- and low-dose groups. The initial increase in both the number of peanut-responsive CD4 T cells and the number of Tregs was transient and no significant differences were found between groups. Basophil activation following peanut stimulation was decreased over the course of OIT and associated with increased peanut-IgG4/IgE ratios. No differences were found between high- and low-dose groups in basophil activation at the time of desensitization or sustained unresponsiveness oral food challenges. CONCLUSIONS AND CLINICAL RELEVANCE: Peanut OIT leads to decreases in pro-allergic cytokines, including IL-5, IL-13, and IL-9 and decreased basophil activation. No differences in T cell or basophil responses were found between subjects on low or high-dose maintenance OIT, which has implications for clinical dosing strategies.


Assuntos
Basófilos , Linfócitos T CD4-Positivos , Citocinas/metabolismo , Dessensibilização Imunológica , Hipersensibilidade a Amendoim , Administração Oral , Basófilos/metabolismo , Basófilos/patologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/patologia , Pré-Escolar , Feminino , Humanos , Masculino , Hipersensibilidade a Amendoim/imunologia , Hipersensibilidade a Amendoim/patologia , Hipersensibilidade a Amendoim/terapia
9.
Eur J Med Chem ; 125: 245-254, 2017 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-27688180

RESUMO

EGFR and VEGFR-2 are involved in pathological disorders and the progression of different kinds of tumors, the combined blockade of EGFR and VEGFR signaling pathways appears to be an attractive approach to cancer therapy. In this work, a series of 4-anilinoquinazoline derivatives containing substituted diaryl urea or glycine methyl ester moiety were designed and identified as EGFR and VEGFR-2 dual inhibitors. Compounds 19i, 19j and 19l exhibited the most potent inhibitory activities against EGFR (IC50 = 1 nM, 78 nM and 51 nM, respectively) and VEGFR-2 (IC50 = 79 nM, 14 nM and 14 nM, respectively), they showed good antiproliferative activities as well. Molecular docking established the interaction of 19i with the DFG-out conformation of VEGFR-2, suggesting that they might be type II kinase inhibitors.


Assuntos
Compostos de Anilina/farmacologia , Receptores ErbB/antagonistas & inibidores , Inibidores de Proteínas Quinases/síntese química , Quinazolinas/farmacologia , Ureia/análogos & derivados , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Compostos de Anilina/síntese química , Antineoplásicos/síntese química , Antineoplásicos/farmacocinética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Simulação de Acoplamento Molecular , Inibidores de Proteínas Quinases/farmacologia , Quinazolinas/síntese química , Ureia/farmacologia
10.
J Chromatogr Sci ; 54(2): 195-9, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26324195

RESUMO

A sensitive and rapid ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS-MS) method was developed to determine sertraline in human plasma. Sample preparation was accomplished through a simple liquid-liquid extraction with ethyl acetate. Chromatographic separation was carried out on an Acquity UPLC BEH C18 column using a gradient mobile phase system composed of acetonitrile and 1% formic acid in water at a flow rate of 0.40 mL/min. Mass spectrometric analysis was performed using a XEVO TQD mass spectrometer coupled with an electrospray ionization source in the positive ion mode. The multiple reaction monitoring transitions of m/z 306.3 → 275.2 and 326.2 → 291.1 were used to quantify for sertraline and midazolam (internal standard), respectively. The linearity of this method was found to be within the concentration range of 1.0-100.0 ng/mL with a lower limit of quantification of 1.0 ng/mL. Only 2.0 min was needed for an analytical run. This fully validated method was successfully applied to the pharmacokinetic study after an oral administration of 100 mg sertraline to 20 Chinese healthy male volunteers.


Assuntos
Ansiolíticos/farmacocinética , Cromatografia Líquida de Alta Pressão/métodos , Sertralina/farmacocinética , Espectrometria de Massas em Tandem/métodos , Ansiolíticos/sangue , Humanos , Masculino , Sertralina/sangue
11.
Respir Res ; 13: 36, 2012 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-22559818

RESUMO

BACKGROUND: Prolonged exposure to hyperoxia in neonates can cause hyperoxic acute lung injury (HALI), which is characterized by increased pulmonary permeability and diffuse infiltration of various inflammatory cells. Disruption of the epithelial barrier may lead to altered pulmonary permeability and maintenance of barrier properties requires intact epithelial tight junctions (TJs). However, in neonatal animals, relatively little is known about how the TJ proteins are expressed in the pulmonary epithelium, including whether expression of TJ proteins is regulated in response to hyperoxia exposure. This study determines whether changes in tight junctions play an important role in disruption of the pulmonary epithelial barrier during hyperoxic acute lung injury. METHODS: Newborn rats, randomly divided into two groups, were exposed to hyperoxia (95% oxygen) or normoxia for 1-7 days, and the severity of lung injury was assessed; location and expression of key tight junction protein occludin and ZO-1 were examined by immunofluorescence staining and immunobloting; messenger RNA in lung tissue was studied by RT-PCR; transmission electron microscopy study was performed for the detection of tight junction morphology. RESULTS: We found that different durations of hyperoxia exposure caused different degrees of lung injury in newborn rats. Treatment with hyperoxia for prolonged duration contributed to more serious lung injury, which was characterized by increased wet-to-dry ratio, extravascular lung water content, and bronchoalveolar lavage fluid (BALF):serum FD4 ratio. Transmission electron microscopy study demonstrated that hyperoxia destroyed the structure of tight junctions and prolonged hyperoxia exposure, enhancing the structure destruction. The results were compatible with pathohistologic findings. We found that hyperoxia markedly disrupted the membrane localization and downregulated the cytoplasm expression of the key tight junction proteins occludin and ZO-1 in the alveolar epithelium by immunofluorescence. The changes of messenger RNA and protein expression of occludin and ZO-1 in lung tissue detected by RT-PCR and immunoblotting were consistent with the degree of lung injury. CONCLUSIONS: These data suggest that the disruption of the pulmonary epithelial barrier induced by hyperoxia is, at least in part, due to massive deterioration in the expression and localization of key TJ proteins.


Assuntos
Hiperóxia/metabolismo , Ocludina/biossíntese , Alvéolos Pulmonares/metabolismo , Mucosa Respiratória/metabolismo , Proteína da Zônula de Oclusão-1/biossíntese , Animais , Animais Recém-Nascidos , Feminino , Hiperóxia/patologia , Gravidez , Alvéolos Pulmonares/patologia , Distribuição Aleatória , Ratos , Ratos Wistar , Mucosa Respiratória/patologia , Junções Íntimas/metabolismo , Junções Íntimas/patologia
12.
J Allergy Clin Immunol ; 127(3): 654-60, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21377034

RESUMO

BACKGROUND: Open-label oral immunotherapy (OIT) protocols have been used to treat small numbers of patients with peanut allergy. Peanut OIT has not been evaluated in double-blind, placebo-controlled trials. OBJECTIVE: To investigate the safety and effectiveness of OIT for peanut allergy in a double-blind, placebo-controlled study. METHODS: In this multicenter study, children ages 1 to 16 years with peanut allergy received OIT with peanut flour or placebo. Initial escalation, build-up, and maintenance phases were followed by an oral food challenge (OFC) at approximately 1 year. Titrated skin prick tests (SPTs) and laboratory studies were performed at regular intervals. RESULTS: Twenty-eight subjects were enrolled in the study. Three peanut OIT subjects withdrew early in the study because of allergic side effects. During the double-blind, placebo-controlled food challenge, all remaining peanut OIT subjects (n = 16) ingested the maximum cumulative dose of 5000 mg (approximately 20 peanuts), whereas placebo subjects (n = 9) ingested a median cumulative dose of 280 mg (range, 0-1900 mg; P < .001). In contrast with the placebo group, the peanut OIT group showed reductions in SPT size (P < .001), IL-5 (P = .01), and IL-13 (P = .02) and increases in peanut-specific IgG(4) (P < .001). Peanut OIT subjects had initial increases in peanut-specific IgE (P < .01) but did not show significant change from baseline by the time of OFC. The ratio of forkhead box protein 3 (FoxP3)(hi): FoxP3(intermediate) CD4+ CD25+ T cells increased at the time of OFC (P = .04) in peanut OIT subjects. CONCLUSION: These results conclusively demonstrate that peanut OIT induces desensitization and concurrent immune modulation. The current study continues and is evaluating the hypothesis that peanut OIT causes long-term immune tolerance.


Assuntos
Hipersensibilidade/imunologia , Hipersensibilidade/terapia , Imunoterapia , Hipersensibilidade a Amendoim/imunologia , Hipersensibilidade a Amendoim/terapia , Administração Oral , Adolescente , Criança , Pré-Escolar , Dessensibilização Imunológica , Feminino , Humanos , Lactente , Masculino
13.
Pediatr Int ; 52(4): 520-6, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20113419

RESUMO

BACKGROUND: The aim of the present study was to investigate p16 promoter methylation in premature rats with chronic lung disease (CLD) induced by hyperoxia. METHODS: Eighty Wistar rats were randomized into the hyperoxia group (fraction of inspired oxygen [FiO(2)] = 900 mL/L) or the control group (FiO(2) = 210 mL/L), 40 for each group. Semi-nested methylation-specific polymerase chain reaction (sn-MSP) was applied to detect p16 promoter hypermethylation in lung tissues. Additionally, p16 mRNA and protein expression was detected on reverse transcription-polymerase chain reaction (RT-PCR), western blot and the strept actividin-biotin complex method. RESULTS: Extended exposure to hyperoxia led to increased methylation, and the methylation level reached a peak in the period of maximum pulmonary fibrosis in the hyperoxia group, while the methylation did not occur in the control group. The methylation rates on semi-nested PCR (sn-PCR) and nested-MSP were, respectively, 52.5% and 42.5% in the hyperoxia group. There was no statistically significant difference between the two methods. The p16 mRNA and protein expression was significantly higher in those with p16 promoter hypermethylation than those without. CONCLUSION: Exposure to hyperoxia may induce p16 promoter hypermethylation in lung tissues in premature rats, and methylation risk increases as exposure extends. p16 promoter methylation induced by hyperoxia may be one of the mechanisms for low p16 mRNA and protein expression.


Assuntos
Inibidor p16 de Quinase Dependente de Ciclina/genética , Metilação de DNA , Hiperóxia/complicações , Pulmão/metabolismo , Regiões Promotoras Genéticas/genética , Fibrose Pulmonar/genética , Animais , Animais Recém-Nascidos , Western Blotting , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Reação em Cadeia da Polimerase , Fibrose Pulmonar/etiologia , Fibrose Pulmonar/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa
14.
Zhonghua Er Ke Za Zhi ; 42(10): 772-6, 2004 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-16221350

RESUMO

OBJECTIVE: Although nonnutritive sucking (NNS) during tube feeding has some benefits on the physiology and development of premature infants, the effect on gastrointestinal function remains controversial. The aim of the study was to evaluate the effects of NNS on the gastric emptying and gastroesophageal reflux (GER) in premature infants. METHODS: Thirty eight healthy appropriate-for-gestational-age premature infants (birth weight ranged from 1050 g to 1790 g, gestational age ranged from 28 weeks to 35 weeks) accepting intermittent nasogastric feeding (INGF) were randomized into NNS group and N-NNS group according to INGF with and without NNS and fed with the same milk formula. Group NNS (n = 18) received oral stimulation by means of a pacifier immediately before feeding, during feeding and then after feeding for 5 min. Group N-NNS (n = 20) served as control and received INGF alone. The following data were collected and recorded, the fluid intake (including both intravenous and oral), milk intake, caloric intake, time of caloric intake reaching 418.4 kJ/(kg x d) by enteral feeding and relevant condition to feeding. Gastric emptying was measured when oral intake reaching above 8 ml/kg while concurrently measuring 24 hour esophageal pH. Real time ultrasonic images of the gastric antrum were obtained and the antral cross sectional area (ACSA) was measured and the half emptying time (50% DeltaACSA) was calculated. Using 24-hour intraesophageal pH monitoring for evaluation of GER, the five parameters of esophageal pH were recorded: number of reflux episodes during 24 hours, reflux index, number of episodes lasting > 5 min, the duration of longest episode and the total time of pH < 4.0. RESULTS: Within two weeks after feeding, there was no significant difference in the fluid intake, caloric intake between the two groups (P > 0.05). Gastric emptying was measured on day 13.26, milk intake had no difference between the two groups and there was no difference in prefeed ACSA. The half gastric emptying time in NNS group was significantly shorter than that in N-NNS group [(58.33 +/- 22.94) min vs. (73.75 +/- 17.76) min, P < 0.05]. Thirty-two of the 38 infants developed GER, the morbidity was 84.2%; the number of reflux episodes during 24 hours was significantly fewer in NNS group than that in N-NNS group [9 (2 - 31) vs. 14 (5 - 31), P < 0.05]; the total time pH < 4.0 and reflux index was lower in NNS than that in N-NNS, but the difference was not statistically significant. The time of reaching 418.4 kJ/(kg x d) by enteral feeding in NNS group was significantly shorter than that in N-NNS group [(12.36 +/- 4.29) d vs. (15.50 +/- 4.58) d, P < 0.05]. The incidence of feeding intolerance such as vomiting and abdominal distension was lower in NNS group than that in N-NNS group, but the difference was not statistically significant (P > 0.05). However, the morbidity of gastric residue in NNS was significantly lower than that in N-NNS (16.7% vs 50.0%, respectively, P < 0.05). CONCLUSION: NNS used during intermittent nasogastric tube feeding is an easy and safe intervention. NNS can improve gastric emptying and decrease the number of reflux episodes, has a positive improving effect on the development of gastrointestinal motility, is beneficial to premature infants for establishing postnatal enteral nutrition.


Assuntos
Nutrição Enteral , Esvaziamento Gástrico/fisiologia , Refluxo Gastroesofágico/prevenção & controle , Recém-Nascido/fisiologia , Recém-Nascido Prematuro/fisiologia , Refluxo Gastroesofágico/fisiopatologia , Motilidade Gastrointestinal/fisiologia , Humanos , Fórmulas Infantis , Fenômenos Fisiológicos da Nutrição do Lactente/fisiologia , Chupetas , Comportamento de Sucção
15.
Zhonghua Er Ke Za Zhi ; 41(2): 91-4, 2003 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-14759306

RESUMO

OBJECTIVE: To evaluate the effects of nonnutritive sucking (NNS) on the nutrient intake, physical growth, feeding-related complications and whole gastrointestinal transit time (WGTT) in premature infants. METHODS: Thirty eight healthy appropriate for gestational age premature infants (birth weights ranged from 1 050 g to 1 790 g) accepting intermittent nasogastric feeding (INGF) were randomized into NNS group and N-NNS group according to INGF with and without NNS and fed with the same milk formula. The following data were collected and recorded, the physical growth parameters (e.g, body weight, length and head circumference) and the birth-weight regaining time, the fluid intake (including both intravenous and oral), caloric intake, time of reaching 418.4 kJ/(kg.d) by enteral feeding, time of putting nasogastric tube, stool frequency and characters, and relevant complications. WGTT were monitored. RESULTS: The birth-weight regaining time in NNS group was significantly shorter than that in N-NNS group [(8.8 +/- 3.7) d vs (11.1 +/- 3.0) d, P < 0.05]. Within two weeks after feeding, there was no significant difference in the increase of body weight, length and head circumference between the two groups (P > 0.05). The time of reaching 418.4 kJ/(kg.d) by enteral feeding in NNS group was significantly shorter than that in N-NNS group [(12.3 +/- 5.1) d vs (15.7 +/- 5.2) d, P < 0.05]; the times of putting nasogastric tube were respectively (13 +/- 10) d and (17 +/- 12) d, but the difference was not significant (P > 0.05). The morbidity of such complications as vomiting and abdominal distension was lower in NNS group than that in N-NNS group, but the difference was not statistically significant (P > 0.05). However, the morbidity of gastric residue in NNS was significantly lower than that in N-NNS (P < 0.05). WGTT of the second week in NNS group was significantly shorter than that in N-NNS [(33 +/- 13) h vs (45 +/- 20) h, P < 0.05]. Stool frequencies of the second week in NNS group were significantly more than those in N-NNS group [(2.26 +/- 0.17) times/d vs (1.79 +/- 0.58) times/d, P < 0.05]. However, there were no significantly differences in WGTT and stool frequencies of the first week between the two groups (P > 0.05). CONCLUSION: NNS was recommended as a beneficial intervention for premature infants during intermittent nasogastric tube feeding.


Assuntos
Nutrição Enteral , Motilidade Gastrointestinal/fisiologia , Fenômenos Fisiológicos da Nutrição do Lactente , Recém-Nascido Prematuro/crescimento & desenvolvimento , Comportamento de Sucção , Feminino , Trato Gastrointestinal/fisiologia , Humanos , Recém-Nascido de Baixo Peso/crescimento & desenvolvimento , Recém-Nascido , Recém-Nascido de muito Baixo Peso/crescimento & desenvolvimento , Masculino
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