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1.
Curr Microbiol ; 81(4): 108, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38461425

RESUMO

Methicillin-resistant Staphylococcus aureus (MRSA) infections have become one of the most threatening multidrug-resistant pathogens. Thus, an ongoing search for anti-MRSA compounds remains an urgent need to effectively treating MRSA infections. Phomopsidione, a novel antibiotic isolated from Diaporthe fraxini, has previously demonstrated potent anti-candidal activity. The present study aimed to investigate the effects of phomopsidione on the viability, virulence, and metabolites profile of MRSA. MRSA was sensitive to phomopsidione in a concentration-dependent manner. Phomopsidione exhibited minimum inhibitory concentration and minimum bactericidal concentration of 62.5 and 500.00 µg/mL against MRSA on broth microdilution assay. The compound showed significant reduction in virulence factors production including extracellular polymeric substances quantification, catalase, and lipase. An untargeted metabolomics analysis using liquid chromatography-high resolution mass spectrometry revealed a significant difference in the metabolites profile of MRSA with 13 putatively identified discriminant metabolites. The present study suggested the potential of phomopsidione as a promising anti-MRSA agent.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Virulência , Antibacterianos/farmacologia , Antibacterianos/química , Testes de Sensibilidade Microbiana , Fatores de Virulência
2.
J Med Internet Res ; 26: e51268, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38421687

RESUMO

BACKGROUND: Accelerated by technological advancements and the recent global pandemic, there is burgeoning interest in digital mental health literacy (DMHL) interventions that can positively affect mental health. However, existing work remains inconclusive regarding the effectiveness of DMHL interventions. OBJECTIVE: This systematic review and meta-analysis investigated the components and modes of DMHL interventions, their moderating factors, and their long-term impacts on mental health literacy and mental health. METHODS: We used a random-effects model to conduct meta-analyses and meta-regressions on moderating effects of DMHL interventions on mental health. RESULTS: Using 144 interventions with 206 effect sizes, we found a moderate effect of DMHL interventions in enhancing distal mental health outcomes (standardized mean difference=0.42, 95% CI -0.10 to 0.73; P<.001) and a large effect in increasing proximal mental health literacy outcomes (standardized mean difference=0.65, 95% CI 0.59-0.74; P<.001). Uptake of DMHL interventions was comparable with that of control conditions, and uptake of DMHL interventions did not moderate the effects on both proximal mental health literacy outcomes and distal mental health outcomes. DMHL interventions were as effective as face-to-face interventions and did not differ by platform type or dosage. DMHL plus interventions (DMHL psychoeducation coupled with other active treatment) produced large effects in bolstering mental health, were more effective than DMHL only interventions (self-help DMHL psychoeducation), and were comparable with non-DMHL interventions (treatment as usual). DMHL interventions demonstrated positive effects on mental health that were sustained over follow-up assessments and were most effective in enhancing the mental health of emerging and older adults. CONCLUSIONS: For theory building, our review and meta-analysis found that DMHL interventions are as effective as face-to-face interventions. DMHL interventions confer optimal effects on mental health when DMHL psychoeducation is combined with informal, nonprofessional active treatment components such as skills training and peer support, which demonstrate comparable effectiveness with that of treatment as usual (client-professional interactions and therapies). These effects, which did not differ by platform type or dosage, were sustained over time. Additionally, most DMHL interventions are found in Western cultural contexts, especially in high-income countries (Global North) such as Australia, the United States, and the United Kingdom, and limited research is conducted in low-income countries in Asia and in South American and African countries. Most of the DMHL studies did not report information on the racial or ethnic makeup of the samples. Future work on DMHL interventions that target racial or ethnic minority groups, particularly the design, adoption, and evaluation of the effects of culturally adaptive DMHL interventions on uptake and mental health functioning, is needed. Such evidence can drive the adoption and implementation of DMHL interventions at scale, which represents a key foundation for practice-changing impact in the provision of mental health resources for individuals and the community. TRIAL REGISTRATION: PROSPERO International Prospective Register of Systematic Reviews CRD42023363995; https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023363995.


Assuntos
Letramento em Saúde , Humanos , Idoso , Saúde Mental , Etnicidade , Grupos Minoritários , África
3.
Am J Respir Cell Mol Biol ; 66(4): 402-414, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35045271

RESUMO

Oxygen supplementation in preterm infants disrupts alveolar epithelial type 2 (AT2) cell proliferation through poorly understood mechanisms. Here, newborn mice are used to understand how hyperoxia stimulates an early aberrant wave of AT2 cell proliferation that occurs between Postnatal Days (PNDs) 0 and 4. RNA-sequencing analysis of AT2 cells isolated from PND4 mice revealed hyperoxia stimulates expression of mitochondrial-specific methylenetetrahydrofolate dehydrogenase 2 and other genes involved in mitochondrial one-carbon coupled folate metabolism and serine synthesis. The same genes are induced when AT2 cells normally proliferate on PND7 and when they proliferate in response to the mitogen fibroblast growth factor 7. However, hyperoxia selectively stimulated their expression via the stress-responsive activating transcription factor 4 (ATF4). Administration of the mitochondrial superoxide scavenger mitoTEMPO during hyperoxia suppressed ATF4 and thus early AT2 cell proliferation, but it had no effect on normative AT2 cell proliferation seen on PND7. Because ATF4 and methylenetetrahydrofolate dehydrogenase are detected in hyperplastic AT2 cells of preterm infant humans and baboons with bronchopulmonary dysplasia, dampening mitochondrial oxidative stress and ATF4 activation may provide new opportunities for controlling excess AT2 cell proliferation in neonatal lung disease.


Assuntos
Fator 4 Ativador da Transcrição/metabolismo , Hiperóxia , Fator 4 Ativador da Transcrição/genética , Animais , Animais Recém-Nascidos , Proliferação de Células , Ácido Fólico/farmacologia , Hiperóxia/metabolismo , Recém-Nascido Prematuro , Camundongos
4.
Am J Physiol Lung Cell Mol Physiol ; 322(4): L581-L592, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35196880

RESUMO

Children and young adults with mutant forms of ataxia telangiectasia mutated (ATM), a kinase involved in DNA damage signaling and mitochondrial homeostasis, suffer from recurrent respiratory infections, immune deficiencies, and obstructive airways disease associated with disorganized airway epithelium. We previously showed in mice how Atm was required to mount a protective immune memory response to influenza A virus [IAV; Hong Kong/X31 (HKx31), H3N2]. Here, Atm wildtype (WT) and knockout (Atm-null) mice were used to investigate how Atm is required to regenerate the injured airway epithelium following IAV infection. When compared with WT mice, naive Atm-null mice had increased airway resistance and reduced lung compliance that worsened during infection before returning to naïve levels by 56 days postinfection (dpi). Although Atm-null lungs appeared pathologically normal before infection by histology, they developed an abnormal proximal airway epithelium after infection that contained E-cadherin+, Sox2+, and Cyp2f2+ cells lacking secretoglobin family 1 A member 1 (Scgb1a1) protein expression. Patchy and low expression of Scgb1a1 were eventually observed by 56 dpi. Genetic lineage tracing in HKx31-infected mice revealed club cells require Atm to rapidly and efficiently restore Scgb1a1 expression in proximal airways. Since Scgb1a1 is an immunomodulatory protein that protects the lung against a multitude of respiratory challenges, failure to efficiently restore its expression may contribute to the respiratory diseases seen in individuals with ataxia telangiectasia.


Assuntos
Ataxia Telangiectasia , Vírus da Influenza A , Influenza Humana , Animais , Ataxia Telangiectasia/genética , Ataxia Telangiectasia/metabolismo , Células Epiteliais/metabolismo , Humanos , Vírus da Influenza A Subtipo H3N2 , Camundongos , Camundongos Knockout
5.
Am J Physiol Lung Cell Mol Physiol ; 323(5): L578-L592, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36068185

RESUMO

Bronchiolitis obliterans (BO) is a debilitating disease of the small airways that can develop following exposure to toxic chemicals as well as respiratory tract infections. BO development is strongly associated with diacetyl (DA) inhalation exposures at occupationally relevant concentrations or severe influenza A viral (IAV) infections. However, it remains unclear whether lower dose exposures or more mild IAV infections can result in similar pathology. In the current work, we combined these two common environmental exposures, DA and IAV, to test whether shorter DA exposures followed by sublethal IAV infection would result in similar airways disease. Adult mice exposed to DA vapors 1 h/day for 5 consecutive days followed by infection with the airway-tropic IAV H3N2 (HKx31) resulted in increased mortality, increased bronchoalveolar lavage (BAL) neutrophil percentage, mixed obstruction and restriction by lung function, and subsequent airway remodeling. Exposure to DA or IAV alone failed to result in significant pathology, whereas mice exposed to DA + IAV showed increased α-smooth muscle actin (αSMA) and epithelial cells coexpressing the basal cell marker keratin 5 (KRT5) with the club cell marker SCGB1A1. To test whether DA exposure impairs epithelial repair after IAV infection, mice were infected first with IAV and then exposed to DA during airway epithelial repair. Mice exposed to IAV + DA developed similar airway remodeling with increased subepithelial αSMA and epithelial cells coexpressing KRT5 and SCGB1A1. Our findings reveal an underappreciated concept that common environmental insults while seemingly harmless by themselves can have catastrophic implications on lung function and long-term respiratory health when combined.


Assuntos
Bronquiolite Obliterante , Vírus da Influenza A , Influenza Humana , Infecções por Orthomyxoviridae , Camundongos , Animais , Humanos , Diacetil/toxicidade , Remodelação das Vias Aéreas , Vírus da Influenza A Subtipo H3N2 , Bronquiolite Obliterante/patologia , Mucosa Respiratória/patologia , Células Epiteliais/patologia , Pulmão/patologia , Influenza Humana/patologia
6.
Am J Physiol Lung Cell Mol Physiol ; 321(4): L750-L763, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34323115

RESUMO

It is well known that supplemental oxygen used to treat preterm infants in respiratory distress is associated with permanently disrupting lung development and the host response to influenza A virus (IAV). However, many infants who go home with normally functioning lungs are also at risk for hyperreactivity after a respiratory viral infection. We recently reported a new, low-dose hyperoxia mouse model (40% for 8 days; 40×8) that causes a transient change in lung function that resolves, rendering 40×8 adult animals functionally indistinguishable from room air controls. Here we report that when infected with IAV, 40×8 mice display an early transient activation of TGFß signaling and later airway hyperreactivity associated with peribronchial inflammation (profibrotic macrophages) and fibrosis compared with infected room air controls, suggesting neonatal oxygen induced hidden molecular changes that prime the lung for hyperreactive airways disease. Although searching for potential activators of TGFß signaling, we discovered that thrombospondin-1 (TSP-1) is elevated in naïve 40×8 mice compared with controls and localized to lung megakaryocytes and platelets before and during IAV infection. Elevated TSP-1 was also identified in human autopsy samples of former preterm infants with bronchopulmonary dysplasia. These findings reveal how low doses of oxygen that do not durably change lung function may prime it for hyperreactive airways disease by changing expression of genes, such as TSP-1, thus helping to explain why former preterm infants who have normal lung function are susceptible to airway obstruction and increased morbidity after viral infection.


Assuntos
Hiper-Reatividade Brônquica/patologia , Displasia Broncopulmonar/patologia , Hiperóxia/patologia , Infecções por Orthomyxoviridae/patologia , Fibrose Pulmonar/patologia , Trombospondina 1/metabolismo , Animais , Linhagem Celular , Modelos Animais de Doenças , Cães , Feminino , Humanos , Vírus da Influenza A/imunologia , Influenza Humana/patologia , Células Madin Darby de Rim Canino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fibrose Pulmonar/virologia , Fator de Crescimento Transformador beta/metabolismo
7.
BMC Cancer ; 21(1): 915, 2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34384377

RESUMO

BACKGROUND: Intracranial hemangiopericytoma is a rare disease and surgery is the mainstay treatment. Although postoperative adjuvant radiotherapy is often used, there are no reports comparing different radiotherapy techniques. The purpose of this study is to analyze the impact of post-operative radiotherapy and different radiotherapy technique on the results in patients with intracranial hemangiopericytoma (HPC). METHODS: We retrospectively reviewed 66 intracranial HPC patients treated between 1999 and 2019 including 29 with surgery followed by radiotherapy (11 with intensity-modulated radiotherapy (IMRT) and 18 with stereotactic radiosurgery (SRS)) and 37 with surgery alone. Chi-square test was used to compare the clinical characteristic between the groups. The Kaplan-Meier method was used to analyze overall survival (OS) and recurrence-free survival (RFS). Multivariate Cox proportional hazards models were used to examine prognostic factors of survival. We also underwent a matched-pair analysis by using the propensity score method. RESULTS: The crude local control rates were 58.6% in the surgery plus post-operative radiotherapy group (PORT) and 67.6% in the surgery alone group (p = 0.453). In the subgroup analysis of the PORT patients, local controls were 72.7% in the IMRT group and 50% in the SRS group (p = 0.228). The median OS in the PORT and surgery groups were 122 months and 98 months, respectively (p = 0.169). The median RFS was 96 months in the PORT group and 72 months in the surgery alone group (p = 0.714). Regarding radiotherapy technique, the median OS and RFS of the SRS group were not significantly different from those in the IMRT group (p = 0.256, 0.960). The median RFS were 112 and 72 months for pathology grade II and III patients, respectively (p = 0.001). Propensity score matching did not change the observed results. CONCLUSION: In this retrospective analysis, PORT did not improve the local control rates nor the survivals. The local control rates after IMRT and SRS were similar even though the IMRT technique had a much higher biological dose compared with the SRS technique.


Assuntos
Neoplasias Encefálicas/radioterapia , Hemangiopericitoma/radioterapia , Cuidados Pós-Operatórios , Adulto , Idoso , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/mortalidade , Terapia Combinada , Feminino , Hemangiopericitoma/diagnóstico , Hemangiopericitoma/mortalidade , Humanos , Estimativa de Kaplan-Meier , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Modelos de Riscos Proporcionais , Radiocirurgia , Radioterapia de Intensidade Modulada , Recidiva , Estudos Retrospectivos , Resultado do Tratamento
8.
AAPS PharmSciTech ; 22(5): 173, 2021 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-34105037

RESUMO

Middle East respiratory syndrome (MERS) is a lethal respiratory disease with its first case reported back in 2012 (Jeddah, Saudi Arabia). It is a novel, single-stranded, positive-sense RNA beta coronavirus (MERS-CoV) that was isolated from a patient who died from a severe respiratory illness. Later, it was found that this patient was infected with MERS. MERS is endemic to countries in the Middle East regions, such as Saudi Arabia, Jordan, Qatar, Oman, Kuwait and the United Arab Emirates. It has been reported that the MERS virus originated from bats and dromedary camels, the natural hosts of MERS-CoV. The transmission of the virus to humans has been thought to be either direct or indirect. Few camel-to-human transmissions were reported earlier. However, the mode of transmission of how the virus affects humans remains unanswered. Moreover, outbreaks in either family-based or hospital-based settings were observed with high mortality rates, especially in individuals who did not receive proper management or those with underlying comorbidities, such as diabetes and renal failure. Since then, there have been numerous reports hypothesising complications in fatal cases of MERS. Over the years, various diagnostic methods, treatment strategies and preventive measures have been strategised in containing the MERS infection. Evidence from multiple sources implicated that no treatment options and vaccines have been developed in specific, for the direct management of MERS-CoV infection. Nevertheless, there are supportive measures outlined in response to symptom-related management. Health authorities should stress more on infection and prevention control measures, to ensure that MERS remains as a low-level threat to public health.


Assuntos
Infecções por Coronavirus/imunologia , Infecções por Coronavirus/fisiopatologia , Coronavírus da Síndrome Respiratória do Oriente Médio/imunologia , Animais , Antivirais/administração & dosagem , Antivirais/imunologia , Camelus/virologia , Quirópteros/virologia , Infecções por Coronavirus/terapia , Infecções por Coronavirus/transmissão , Humanos , Coronavírus da Síndrome Respiratória do Oriente Médio/efeitos dos fármacos , Coronavírus da Síndrome Respiratória do Oriente Médio/isolamento & purificação , Arábia Saudita/epidemiologia , Zoonoses Virais/epidemiologia , Zoonoses Virais/imunologia , Zoonoses Virais/transmissão
9.
Pediatr Res ; 87(7): 1201-1210, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31835269

RESUMO

BACKGROUND: Supplemental oxygen exposure administered to premature infants is associated with chronic lung disease and abnormal pulmonary function. This study used mild (40%), moderate (60%), and severe (80%) oxygen to determine how hyperoxia-induced changes in lung structure impact pulmonary mechanics in mice. METHODS: C57BL/6J mice were exposed to room air or hyperoxia from birth through postnatal day 8. Baseline pulmonary function and methacholine challenge was assessed at 4 and 8 weeks of age, accompanied by immunohistochemical assessments of both airway (smooth muscle, tethering) and alveolar (simplification, elastin deposition) structure. RESULTS: Mild/moderate hyperoxia increased baseline airway resistance (40% only) and airway hyperreactivity (40 and 60%) at 4 weeks accompanied by increased airway smooth muscle deposition, which resolved at 8 weeks. Severe hyperoxia increased baseline compliance, baseline resistance, and total elastin/surface area ratio without increasing airway hyperreactivity, and was accompanied by increased alveolar simplification, decreased airway tethering, and changes in elastin distribution at both time points. CONCLUSIONS: Mild to moderate hyperoxia causes changes in airway function and airway hyperreactivity with minimal parenchymal response. Severe hyperoxia drives its functional changes through alveolar simplification, airway tethering, and elastin redistribution. These differential responses can be leveraged to further develop hyperoxia mouse models.


Assuntos
Hiperóxia/fisiopatologia , Pulmão/crescimento & desenvolvimento , Mecânica Respiratória , Animais , Animais Recém-Nascidos , Relação Dose-Resposta a Droga , Feminino , Pulmão/patologia , Complacência Pulmonar , Masculino , Cloreto de Metacolina/administração & dosagem , Cloreto de Metacolina/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Agonistas Muscarínicos/administração & dosagem , Agonistas Muscarínicos/farmacologia , Músculo Liso/fisiopatologia , Alvéolos Pulmonares/fisiopatologia , Testes de Função Respiratória , Mecânica Respiratória/efeitos dos fármacos , Fatores Sexuais
10.
Am J Physiol Lung Cell Mol Physiol ; 317(5): L591-L601, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31509427

RESUMO

Ataxia-telangiectasia (A-T), caused by mutations in the A-T mutated (ATM) gene, is a neurodegenerative disorder affecting ∼1 in 40,000-100,000 children. Recurrent respiratory infections are a common and challenging comorbidity, often leading to the development of bronchiectasis in individuals with A-T. The role of ATM in development of immune memory in response to recurrent respiratory viral infections is not well understood. Here, we infect wild-type (WT) and Atm-null mice with influenza A virus (IAV; HKx31, H3N2) and interrogate the immune memory with secondary infections designed to challenge the B cell memory response with homologous infection (HKx31) and the T cell memory response with heterologous infection (PR8, H1N1). Although Atm-null mice survived primary and secondary infections, they lost more weight than WT mice during secondary infections. This enhanced morbidity to secondary infections was not attributed to failure to effectively clear virus during the primary IAV infection. Instead, Atm-null mice developed persistent peribronchial inflammation, characterized in part by clusters of B220+ B cells. Additionally, levels of select serum antibodies to hemagglutinin-specific IAV were significantly lower in Atm-null than WT mice. These findings reveal that Atm is required to mount a proper memory response to a primary IAV infection, implying that vaccination of children with A-T by itself may not be sufficiently protective against respiratory viral infections.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Memória Imunológica/imunologia , Vírus da Influenza A/imunologia , Pulmão/imunologia , Mutação , Infecções por Orthomyxoviridae/imunologia , Animais , Proteínas Mutadas de Ataxia Telangiectasia/fisiologia , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/virologia , Pulmão/metabolismo , Pulmão/virologia , Camundongos , Camundongos Knockout , Infecções por Orthomyxoviridae/metabolismo , Infecções por Orthomyxoviridae/virologia
11.
Am J Physiol Lung Cell Mol Physiol ; 314(5): L846-L859, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29345197

RESUMO

Supplemental oxygen given to preterm infants has been associated with permanently altering postnatal lung development. Now that these individuals are reaching adulthood, there is growing concern that early life oxygen exposure may also promote cardiovascular disease through poorly understood mechanisms. We previously reported that adult mice exposed to 100% oxygen between postnatal days 0 and 4 develop pulmonary hypertension, defined pathologically by capillary rarefaction, dilation of arterioles and veins, cardiac failure, and a reduced lifespan. Here, Affymetrix Gene Arrays are used to identify early transcriptional changes that take place in the lung before pulmonary capillary rarefaction. We discovered neonatal hyperoxia reduced expression of cardiac muscle genes, including those involved in contraction, calcium signaling, mitochondrial respiration, and vasodilation. Quantitative RT-PCR, immunohistochemistry, and genetic lineage mapping using Myh6CreER; Rosa26RmT/mG mice revealed this reflected loss of pulmonary vein cardiomyocytes. The greatest loss of cadiomyocytes was seen within the lung followed by a graded loss beginning at the hilum and extending into the left atrium. Loss of these cells was seen by 2 wk of age in mice exposed to ≥80% oxygen and was attributed, in part, to reduced proliferation. Administering mitoTEMPO, a scavenger of mitochondrial superoxide during neonatal hyperoxia prevented loss of these cells. Since pulmonary vein cardiomyocytes help pump oxygen-rich blood out of the lung, their early loss following neonatal hyperoxia may contribute to cardiovascular disease seen in these mice, and perhaps in people who were born preterm.


Assuntos
Biomarcadores/metabolismo , Hiperóxia/fisiopatologia , Hipertensão Pulmonar/patologia , Mitocôndrias/química , Miócitos Cardíacos/patologia , Oxigênio/metabolismo , Veias Pulmonares/patologia , Animais , Animais Recém-Nascidos , Células Cultivadas , Perfilação da Expressão Gênica , Hipertensão Pulmonar/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/genética , Mitocôndrias/metabolismo , Miócitos Cardíacos/metabolismo , Oxirredução , Veias Pulmonares/metabolismo
12.
Am J Respir Cell Mol Biol ; 56(4): 453-464, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27967234

RESUMO

An aberrant oxygen environment at birth increases the severity of respiratory viral infections later in life through poorly understood mechanisms. Here, we show that alveolar epithelial cell (AEC) 2 cells (AEC2s), progenitors for AEC1 cells, are depleted in adult mice exposed to neonatal hypoxia or hyperoxia. Airway cells expressing surfactant protein (SP)-C and ATP binding cassette subfamily A member 3, alveolar pod cells expressing keratin (KRT) 5, and pulmonary fibrosis were observed when these mice were infected with a sublethal dose of HKx31, H3N2 influenza A virus. This was not seen in infected siblings birthed into room air. Genetic lineage tracing studies in mice exposed to neonatal hypoxia or hyperoxia revealed pre-existing secretoglobin 1a1+ cells produced airway cells expressing SP-C and ATP binding cassette subfamily A member 3. Pre-existing Kr5+ progenitor cells produced squamous alveolar cells expressing receptor for advanced glycation endproducts, aquaporin 5, and T1α in alveoli devoid of AEC2s. They were not the source of KRT5+ alveolar pod cells. These oxygen-dependent changes in epithelial cell regeneration and fibrosis could be recapitulated by conditionally depleting AEC2s in mice using diphtheria A toxin and then infecting with influenza A virus. Likewise, airway cells expressing SP-C and alveolar cells expressing KRT5 were observed in human idiopathic pulmonary fibrosis. These findings suggest that alternative progenitor lineages are mobilized to regenerate the alveolar epithelium when AEC2s are severely injured or depleted by previous insults, such as an adverse oxygen environment at birth. Because these lineages regenerate AECs in spatially distinct compartments of a lung undergoing fibrosis, they may not be sufficient to prevent disease.


Assuntos
Envelhecimento/metabolismo , Células Epiteliais Alveolares/citologia , Linhagem da Célula , Células-Tronco/citologia , Células Epiteliais Alveolares/efeitos dos fármacos , Células Epiteliais Alveolares/metabolismo , Animais , Animais Recém-Nascidos , Linhagem da Célula/efeitos dos fármacos , Humanos , Fibrose Pulmonar Idiopática/metabolismo , Fibrose Pulmonar Idiopática/patologia , Queratina-5/metabolismo , Camundongos , Modelos Biológicos , Oxigênio/farmacologia , Proteína C Associada a Surfactante Pulmonar/metabolismo , Regeneração/efeitos dos fármacos , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismo , Uteroglobina/metabolismo
13.
Am J Physiol Lung Cell Mol Physiol ; 313(5): L940-L949, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-28798254

RESUMO

Infants born prematurely often require supplemental oxygen, which contributes to aberrant lung development and increased pulmonary morbidity following a respiratory viral infection. We have been using a mouse model to understand how early-life hyperoxia affects the adult lung response to influenza A virus (IAV) infection. Prior studies showed how neonatal hyperoxia (100% oxygen) increased sensitivity of adult mice to infection with IAV [IAV (A/Hong Kong/X31) H3N2] as defined by persistent inflammation, pulmonary fibrosis, and mortality. Since neonatal hyperoxia alters lung structure, we used a novel fluorescence-expressing reporter strain of H1N1 IAV [A/Puerto Rico/8/34 mCherry (PR8-mCherry)] to evaluate whether it also altered early infection of the respiratory epithelium. Like Hong Kong/X31, neonatal hyperoxia increased morbidity and mortality of adult mice infected with PR8-mCherry. Whole lung imaging and histology suggested a modest increase in mCherry expression in adult mice exposed to neonatal hyperoxia compared with room air-exposed animals. However, this did not reflect an increase in airway or alveolar epithelial infection when mCherry-positive cells were identified and quantified by flow cytometry. Instead, a modest increase in the number of CD45-positive macrophages expressing mCherry was detected. While neonatal hyperoxia does not alter early epithelial infection with IAV, it may increase the activity of macrophages toward infected cells, thereby enhancing early epithelial injury.


Assuntos
Hiperóxia/virologia , Infecções por Orthomyxoviridae/virologia , Oxigênio/metabolismo , Fibrose Pulmonar/virologia , Animais , Animais Recém-Nascidos , Modelos Animais de Doenças , Epitélio/virologia , Humanos , Hiperóxia/patologia , Vírus da Influenza A , Pulmão/crescimento & desenvolvimento , Pulmão/patologia , Pulmão/virologia , Camundongos Endogâmicos C57BL
14.
Stem Cells ; 34(5): 1396-406, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26891117

RESUMO

Alveolar epithelial type II cells (AEC2) maintain pulmonary homeostasis by producing surfactant, expressing innate immune molecules, and functioning as adult progenitor cells for themselves and alveolar epithelial type I cells (AEC1). How the proper number of alveolar epithelial cells is determined in the adult lung is not well understood. Here, BrdU labeling, genetic lineage tracing, and targeted expression of the anti-oxidant extracellular superoxide dismutase in AEC2s are used to show how the oxygen environment at birth influences postnatal expansion of AEC2s and AEC1s in mice. Birth into low (12%) or high (≥60%) oxygen stimulated expansion of AEC2s through self-renewal and differentiation of the airway Scgb1a1 + lineage. This non-linear or hormesis response to oxygen was specific for the alveolar epithelium because low oxygen stimulated and high oxygen inhibited angiogenesis as defined by changes in V-cadherin and PECAM (CD31). Although genetic lineage tracing studies confirmed adult AEC2s are stem cells for AEC1s, we found no evidence that postnatal growth of AEC1s were derived from self-renewing Sftpc + or the Scbg1a1 + lineage of AEC2s. Taken together, our results show how a non-linear response to oxygen at birth promotes expansion of AEC2s through two distinct lineages. Since neither lineage contributes to the postnatal expansion of AEC1s, the ability of AEC2s to function as stem cells for AEC1s appears to be restricted to the adult lung. Stem Cells 2016;34:1396-1406.


Assuntos
Envelhecimento/fisiologia , Células Epiteliais Alveolares/citologia , Células Epiteliais/citologia , Pulmão/citologia , Oxigênio/farmacologia , Células-Tronco/citologia , Células Epiteliais Alveolares/efeitos dos fármacos , Células Epiteliais Alveolares/metabolismo , Animais , Animais Recém-Nascidos , Diferenciação Celular/efeitos dos fármacos , Linhagem da Célula/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Epitélio/efeitos dos fármacos , Epitélio/metabolismo , Feminino , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Camundongos , Modelos Biológicos
15.
Chem Res Toxicol ; 29(7): 1118-31, 2016 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-27245204

RESUMO

Diclofenac and lumiracoxib are two highly analogous 2-phenylaminophenylacetic acid anti-inflammatory drugs exhibiting occasional dose-limiting hepatotoxicities. Prior data indicate that bioactivation and reactive metabolite formation play roles in the observed toxicity, but the exact chemical influence of the substituents remains elusive. In order to elucidate the role of chemical influence on metabolism related toxicity, metabolic stability and electrophilic reactivity were investigated for a series of structurally related analogues and their resulting metabolites. The resulting analogues embody progressive physiochemical changes through varying halogeno- and aliphatic substituents at two positions and were subjected to in vitro human liver microsomal metabolic stability and cell-based GSH depletion assays (to measure electrophilic reactivity). LC-MS/MS analysis of the GSH trapped reactive intermediates derived from the analogues was then used to identify the putative structures of reactive metabolites. We found that chemical modifications of the structural backbone led to noticeable perturbations of metabolic stability, electrophilic reactivity, and structures and composition of reactive metabolites. With the acquired data, the relationships between stability, reactivity, and toxicity were investigated in an attempt to correlate between Phase I metabolism and in vitro toxicity. A positive correlation was identified between reactivity and in vitro toxicity, indicating that electrophilic reactivity can be an indicator for in vitro toxicity. All in all, the effect of substituents on the structures and reactivity of the metabolites, however subtle the changes, should be taken into consideration during future drug design involving similar chemical features.


Assuntos
Acetatos/química , Acetatos/metabolismo , Cromatografia Líquida , Glutationa/metabolismo , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
16.
Gen Comp Endocrinol ; 227: 84-93, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26686318

RESUMO

Early-life stress can cause long-term effects in the adulthood such as alterations in behaviour, brain functions and reproduction. DNA methylation is a mechanism of epigenetic change caused by early-life stress. Dexamethasone (DEX) was administered to zebrafish larvae to study its effect on reproductive dysfunction. The level of GnRH2, GnRH3, Kiss1 and Kiss2 mRNAs were measured between different doses of DEX treatment groups in adult zebrafish. Kiss1 and GnRH2 expression were increased in the 200mg/L DEX treated while Kiss2 and GnRH3 mRNA levels were up-regulated in the 2mg/L DEX-treated zebrafish. The up-regulation may be related to programming effect of DEX in the zebrafish larvae, causing overcompensation mechanism to increase the mRNA levels. Furthermore, DEX treatment caused negative impact on the development and maturation of the testes, in particular spermatogenesis. Therefore, immature gonadal development may cause positive feedback by increasing GnRH and Kiss. This indicates that DEX can alter the regulation of GnRH2, GnRH3, Kiss1 and Kiss2 in adult zebrafish, which affects maturation of gonads. Computer analysis of 1.5 kb region upstream of the 5' UTR of Kiss1, Kiss2, GnRH2 and GnRH3 promoter showed that there are putative binding sites of glucocorticoid response element and transcription factors involved in stress response. GnRH3 promoter analysed from pre-optic area, ventral telencephalon and ventral olfactory bulb showed higher methylation at CpG residues located on -1410, -1377 and -1355 between control and 2mg/L DEX-treated groups. Hence, early-life DEX treatment can alter methylation of GnRH3 gene promoter, which subsequently affects gene regulation and reproductive functions.


Assuntos
Encéfalo/metabolismo , Metilação de DNA , Hormônio Liberador de Gonadotropina/genética , Kisspeptinas/genética , Regiões Promotoras Genéticas , Ácido Pirrolidonocarboxílico/análogos & derivados , Estresse Psicológico/genética , Peixe-Zebra/genética , Animais , Hormônio Liberador de Gonadotropina/metabolismo , Gônadas/metabolismo , Kisspeptinas/metabolismo , Masculino , Ácido Pirrolidonocarboxílico/metabolismo , Reprodução , Estresse Psicológico/metabolismo , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/metabolismo
17.
J Appl Clin Med Phys ; 17(1): 428­439, 2016 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-26894355

RESUMO

The construction of a conventional prostate needle (seeds) implant template restricts needles tilting or incline insertion when it is necessary to approach a seminal vesicle or to avoid the obstruction of symphysis pubis. To overcome the disadvantages of conventional templates, we developed a special template for guiding needles incline insertion and fixation for prostate needle implant. Phantom needles implantation was performed. Two acrylic boards, each 7.5 cm in width by 7.5 cm in length and 0.5 cm thickness, were drilled with a set of domed holes and cones with embedded template ball inside this combination to provide firm grip and fixation in prostate needle implantation. The specially designed domed-cones combination acrylic board provides a needle of up to 60° rotation flexibility application. Some areas that could not be covered in a conventional parallel needle holes template could now be covered by using this new template. The covering index of prostate radiation dosage is up to 84.5%. The specially designed domed-cones acrylic board combination provides not only a reliable means of needle fixation and rotational function, but also a superior dose distribution in the anterior portion of the prostate and good coverage of a seminal vesicle. This special template is a feasible design for prostate needles or seeds implant brachytherapy.


Assuntos
Braquiterapia , Imagens de Fantasmas , Neoplasias da Próstata/radioterapia , Próteses e Implantes , Humanos , Masculino , Agulhas , Radiometria , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Radioterapia de Intensidade Modulada , Rotação
18.
J Proteome Res ; 14(11): 4734-42, 2015 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-26506213

RESUMO

Physical and psychological stress have been shown to modulate multiple aspects of gastrointestinal (GI) physiology, but its molecular basis remains elusive. We therefore characterized the stress-induced metabolic phenotype (metabotype) in soldiers during high-intensity combat training and correlated the metabotype with changes in GI symptoms and permeability. In a prospective, longitudinal study, urinary metabotyping was conducted on 38 male healthy soldiers during combat training and a rest period using gas chromatography-mass spectrometry. The urinary metabotype during combat training was clearly distinct from the rest period (partial least-squares discriminant analysis (PLSDA) Q(2) = 0.581), confirming the presence of a unique stress-induced metabotype. Differential metabolites related to combat stress were further uncovered, including elevated pyroglutamate and fructose, and reduced gut microbial metabolites, namely, hippurate and m-hydroxyphenylacetate (p < 0.05). The extent of pyroglutamate upregulation exhibited a positive correlation with an increase in IBS-SSS in soldiers during combat training (r = 0.5, p < 0.05). Additionally, the rise in fructose levels was positively correlated with an increase in intestinal permeability (r = 0.6, p < 0.005). In summary, protracted and mixed psychological and physical combat-training stress yielded unique metabolic changes that corresponded with the incidence and severity of GI symptoms and alteration in intestinal permeability. Our study provided novel molecular insights into stress-induced GI perturbations, which could be exploited for future biomarker research or development of therapeutic strategies.


Assuntos
Ansiedade/urina , Depressão/urina , Frutose/urina , Síndrome do Intestino Irritável/urina , Metaboloma , Ácido Pirrolidonocarboxílico/urina , Estresse Psicológico/urina , Ansiedade/diagnóstico , Ansiedade/fisiopatologia , Biomarcadores/urina , Depressão/diagnóstico , Depressão/fisiopatologia , Cromatografia Gasosa-Espectrometria de Massas , Hipuratos/metabolismo , Humanos , Mucosa Intestinal/metabolismo , Intestinos/fisiopatologia , Síndrome do Intestino Irritável/diagnóstico , Síndrome do Intestino Irritável/fisiopatologia , Análise dos Mínimos Quadrados , Estudos Longitudinais , Masculino , Militares , Permeabilidade , Fenilacetatos/metabolismo , Estudos Prospectivos , Estresse Fisiológico , Estresse Psicológico/diagnóstico , Estresse Psicológico/fisiopatologia , Adulto Jovem
19.
Am J Physiol Lung Cell Mol Physiol ; 308(1): L76-85, 2015 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-25381024

RESUMO

Respiratory distress in preterm or low birth weight infants is often treated with supplemental oxygen. However, this therapy can disrupt normal lung development and architecture and alter responses to respiratory insults. Similarly, exposure of newborn mice to 100% oxygen during saccular lung development leads to permanent alveolar simplification, and upon challenge with influenza A virus, mice exhibit reduced host resistance. Natural killer (NK) cells are key players in antiviral immunity, and emerging evidence suggest they also help to maintain homeostasis in peripheral tissues, including the lung, by promoting epithelial cell regeneration via IL-22. We tested the hypothesis that adult mice exposed to hyperoxia as neonates have modified NK cell responses to infection. We report here that mice exposed to neonatal hyperoxia had fewer IL-22(+) NK cells in their lungs after influenza virus challenge and a parallel increase in IFN-γ(+) NK cells. Using reciprocal bone marrow chimeric mice, we show that exposure of either hematopoietic or nonhematopoietic cells was sufficient to increase the severity of infection and to diminish the frequency of IL-22(+) NK cells in the infected lung. Overall, our findings suggest that neonatal hyperoxia leads to long-term changes in the reparative vs. cytotoxic nature of NK cells and that this is due in part to intrinsic changes in hematopoietic cells. These differences may contribute to how oxygen alters the host response to respiratory viral infections.


Assuntos
Hiperóxia/imunologia , Imunidade Celular , Vírus da Influenza A/imunologia , Células Matadoras Naturais/imunologia , Infecções por Orthomyxoviridae/imunologia , Alvéolos Pulmonares/imunologia , Animais , Animais Recém-Nascidos , Hiperóxia/patologia , Interferon gama/imunologia , Interleucinas/imunologia , Células Matadoras Naturais/patologia , Camundongos , Infecções por Orthomyxoviridae/patologia , Alvéolos Pulmonares/patologia , Interleucina 22
20.
Am J Respir Cell Mol Biol ; 50(4): 757-66, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24188066

RESUMO

Supplemental oxygen used to treat infants born prematurely disrupts angiogenesis and is a risk factor for persistent pulmonary disease later in life. Although it is unclear how neonatal oxygen affects development of the respiratory epithelium, alveolar simplification and depletion of type II cells has been observed in adult mice exposed to hyperoxia between postnatal Days 0 and 4. Because hyperoxia inhibits cell proliferation, we hypothesized that it depleted the adult lung of type II cells by inhibiting their proliferation at birth. Newborn mice were exposed to room air (RA) or hyperoxia, and the oxygen-exposed mice were recovered in RA. Hyperoxia stimulated mRNA expressed by type II (Sftpc, Abca3) and type I (T1α, Aquaporin 5) cells and inhibited Pecam expressed by endothelial cells. 5-Bromo-2'-deoxyuridine labeling and fate mapping with enhanced green fluorescence protein controlled statically by the Sftpc promoter or conditionally by the Scgb1a1 promoter revealed increased Sftpc and Abca3 mRNA seen on Day 4 reflected an increase in expansion of type II cells shortly after birth. When mice were returned to RA, this expanded population of type II cells was slowly depleted until few were detected by 8 weeks. These findings reveal that hyperoxia stimulates alveolar epithelial cell expansion when it disrupts angiogenesis. The loss of type II cells during recovery in RA may contribute to persistent pulmonary diseases such as those reported in children born preterm who were exposed to supplemental oxygen.


Assuntos
Células Epiteliais Alveolares/patologia , Proliferação de Células , Hiperóxia/patologia , Alvéolos Pulmonares/patologia , Células Epiteliais Alveolares/metabolismo , Animais , Animais Recém-Nascidos , Modelos Animais de Doenças , Regulação da Expressão Gênica , Genes Reporter , Proteínas de Fluorescência Verde/biossíntese , Proteínas de Fluorescência Verde/genética , Hiperóxia/genética , Hiperóxia/metabolismo , Proteínas Luminescentes/biossíntese , Proteínas Luminescentes/genética , Camundongos , Camundongos Transgênicos , Regiões Promotoras Genéticas , Alvéolos Pulmonares/metabolismo , Proteína C Associada a Surfactante Pulmonar/genética , RNA Mensageiro/metabolismo , Fatores de Tempo , Uteroglobina/genética , Proteína Vermelha Fluorescente
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