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1.
J Nat Prod ; 87(4): 1209-1216, 2024 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-38394380

RESUMO

Seven new 4-hydroxy-6-phenyl-2H-pyran-2-one (HPPO) derived meroterpenoids, 1-methyl-12a,12b-epoxyarisugacin M (1), 1-methyl-4a,12b-epoxyarisugacin M (2), 2,3-dihydroxy-3,4a-epoxy-12a-dehydroxyisoterreulactone A (3), 2-hydroxy-12a-dehydroxyisoterreulactone A (4), 3'-demethoxyterritrems B' (5), 4a-hydroxyarisugacin P (6), and 1-epi-arisugacin H (7), together with two known analogues (8 and 9), were isolated from the marine-derived fungal strain Penicillium sp. SCSIO 41691. Their structures were elucidated by spectroscopic methods, and the absolute configurations of compounds 1 and 3 were determined by single-crystal X-ray diffraction. Among them, 1 and 2 had a unique methyl migration in the basic meroterpenoid skeleton with a 12a,12b-epoxy or 4a,12b-epoxy group, and 3 was a highly oxygenated HPPO-derived meroterpenoid featuring a rare 6/5/6/6/6/6 hexacyclic system with a 3,4a-epoxy group. Biologically, 5 exhibited inhibitory activity against lipopolysaccharide-induced nitric oxide production in RAW 264.7 cells with an IC50 value of 21 µM, more potent than the positive control indomethacin.


Assuntos
Penicillium , Terpenos , Penicillium/química , Terpenos/farmacologia , Terpenos/química , Terpenos/isolamento & purificação , Estrutura Molecular , Animais , Camundongos , Células RAW 264.7 , Óxido Nítrico/biossíntese , Cristalografia por Raios X , Biologia Marinha , Lipopolissacarídeos/farmacologia
2.
Sleep Breath ; 27(5): 1829-1837, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-36853471

RESUMO

PURPOSE: To determine obstructive sleep apnea (OSA) phenotypes using cluster analysis including variables of sleep perception and sleep quality and to further explore factors correlated with poor sleep quality in different clusters. METHODS: This retrospective study included patients with OSA undergoing polysomnography (PSG) between December 2020 and April 2022. Two-step cluster analysis was performed to detect distinct clusters using sleep perception variables including discrepancy in total sleep time (TST), sleep onset latency (SOL), and wakefulness after sleep onset (WASO); objective TST, SOL, and WASO; and sleep quality. One-way analysis of variance or chi-squared tests were used to compare clinical and PSG characteristics between clusters. Binary logistic regression analyses were used to explore factors correlated with poor sleep quality. RESULTS: A total of 1118 patients were included (81.6% men) with mean age ± SD 43.3 ± 13.1 years, Epworth sleepiness score, 5.7 ± 4.4, and insomnia severity index 3.0 ± 2.4. Five distinct OSA clusters were identified: cluster 1 (n = 254), underestimated TST; cluster 2 (n = 158), overestimated TST; cluster 3 (n = 169), overestimated SOL; cluster 4 (n = 155), normal sleep discrepancy and poor sleep quality; and cluster 5 (n = 382), normal sleep discrepancy and good sleep quality. Patients in cluster 2 were older, more commonly had hypertension, and had the lowest apnea-hypopnea index and oxygen desaturation index. Age and sleep efficiency were correlated with poor sleep quality in clusters 1, 2, and 5, and also AHI in cluster 2. CONCLUSION: Subgroups of patients with OSA have different patterns of sleep perception and quality that may help us to further understand the characteristics of sleep perception in OSA and provide clues for personalized treatment.


Assuntos
Apneia Obstrutiva do Sono , Distúrbios do Início e da Manutenção do Sono , Masculino , Humanos , Feminino , Qualidade do Sono , Estudos Retrospectivos , Sono , Apneia Obstrutiva do Sono/diagnóstico , Apneia Obstrutiva do Sono/epidemiologia , Análise por Conglomerados , Fenótipo , Percepção
3.
Mar Drugs ; 21(11)2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37999399

RESUMO

Six new thiodiketopiperazine-class alkaloids lecanicilliums A-F were isolated from the mangrove sediment-derived fungus Lecanicillium kalimantanense SCSIO41702, together with thirteen known analogues. Their structures were determined by spectroscopic analysis. The absolute configurations were determined by quantum chemical calculations. Electronic circular dichroism (ECD) spectra and the structure of Lecanicillium C were further confirmed by a single-crystal X-ray diffraction analysis. Lecanicillium A contained an unprecedented 6/5/6/5/7/6 cyclic system with a spirocyclic center at C-2'. Biologically, lecanicillium E, emethacin B, and versicolor A displayed significant cytotoxicity against human lung adenocarcinoma cell line H1975, with IC50 values of 7.2~16.9 µM, and lecanicillium E also showed antibacterial activity against four pathogens with MIC values of 10~40 µg/mL. Their structure-activity relationship is also discussed.


Assuntos
Alcaloides , Hypocreales , Humanos , Alcaloides/farmacologia , Antibacterianos/química , Linhagem Celular , Estrutura Molecular
4.
J Perinat Med ; 51(4): 538-545, 2023 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-36435526

RESUMO

OBJECTIVES: Vitamin D plays an essential role in neonatal skeletal development and maternal weight gain during pregnancy. We aim to study the association between vitamin D status, maternal weight, and materno-neonatal bone metabolism parameters. METHODS: From January to June 2017, we conducted this cross-sectional study among 103 pregnant women (21-42 years old) and their singletons. The levels of serum 25-(OH)D, PTH, P1NP, OC, and CTX were measured for mothers and neonates (cord blood). Serum vitamin D and OC were measured using chemiluminescence and two-site immunoradiometric assay, respectively. Meanwhile, P1NP, CTX, and PTH were measured by ELISA. RESULTS: The average serum vitamin D levels from mothers were 15.1 ng/mL during pregnancy and 16.2 ng/mL in the umbilical cord. At baseline, vitamin D deficient mothers were more likely to have higher PTH (36.4 vs. 18 pg/mL; p=0.029) and lower P1NP levels (90 vs. 92.5 ng/mL; p=0.026). Also, vitamin D deficient status was associated with lower fetal weight (3,293 vs. 3,358 g; p=0.019). Maternal weight was significantly correlated with P1NP (65.86 vs. 109.35; p=0.001) and OC (14.52 vs. 18.24; p=0.038), as well as cord vitamin D level (13.31 vs. 18.46; p=0.039) among normal vs. overweight women. No significant differences were found for the correlation between maternal weight and fetal parameters except for fetal weight which significantly increased with the increase in maternal weight (overweight vs. obese women=3,280 vs. 3,560; p=0.06). CONCLUSIONS: Maternal vitamin D status is associated with maternal and neonatal bone metabolism parameters as well as maternal and neonatal weight.


Assuntos
Peso Fetal , Deficiência de Vitamina D , Vitamina D , Adulto , Feminino , Recém-Nascido , Gravidez , Adulto Jovem , Vitamina D/sangue , Vitamina D/metabolismo , Deficiência de Vitamina D/complicações , Humanos , Estudos Transversais , Osso e Ossos/metabolismo
5.
Hum Factors ; 65(3): 419-434, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-34148475

RESUMO

OBJECTIVE: This prospective study assessed the risk of developing rotator cuff syndrome (RCS) with separate or specific combinations of biomechanical exposures measures, controlling for individual confounders. BACKGROUND: Compared with other musculoskeletal disorders, rates of work-related shoulder musculoskeletal disorders have been declining more slowly. METHOD: We conducted up to 2 years of individual, annual assessments of covariates, exposures, and health outcomes for 393 U.S. manufacturing and healthcare workers without RCS at baseline. Task-level biomechanical exposures assessed exposure to forceful exertions (level, exertion rates, duty cycles), vibration, and upper arm postures (flexion, abduction). Hazard ratios (HRs) were calculated with Cox proportional hazard models. RESULTS: We observed 39 incident RCS cases in 694 person-years (incidence rate = 5.62 per 100 person-years). Adjusting for confounders, we found increased risk of incident RCS associated with forceful hand exertions per minute for three upper arm posture tertiles: flexion ≥45° (≥28.2% time, HR = 1.11, CI [1.01, 1.22]), abduction ≥30° (11.9-21.2%-time, HR = 1.18, CI [1.04, 1.34]), and abduction >60° (≥4.8% time, HR = 1.16, CI [1.04, 1.29]). We failed to observe statistically significant effects for other interactions or any separate measures of biomechanical exposure. CONCLUSION: This study highlights the importance of assessing combinations of exposure to forceful repetition and upper arm elevation when developing interventions for preventing RCS. APPLICATION: Based on these results, interventions that reduce exposure to forceful repetition (i.e., lower force levels and/or slower exertion rates) may reduce the risk of RCS, especially when upper arm elevation cannot be avoided.


Assuntos
Doenças Musculoesqueléticas , Doenças Profissionais , Humanos , Manguito Rotador , Estudos Prospectivos , Doenças Profissionais/epidemiologia , Doenças Profissionais/etiologia , Fatores de Risco , Pessoal de Saúde
6.
J Nat Prod ; 85(8): 2071-2081, 2022 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-35930265

RESUMO

Seven new decahydrofluorene-class alkaloids, pyrrospirones K-Q (1-7), together with six known analogues (8-13) were isolated from the marine-derived fungal strain Penicillium sp. SCSIO 41512. Their structures were determined by extensive spectroscopic analysis, and their absolute configurations were established by single-crystal X-ray diffraction analysis and quantum chemical calculations of electronic circular dichroism spectra. Compounds 1 and 3 possess a novel decahydrofluorene-class alkaloid skeleton with a 6/5/6/8/5/6/13 and a 6/5/6/5/6/13 polycyclic system, respectively. Biologically, 13 displayed significant inhibitory activity against protein tyrosine phosphatases CD45, TCPTP, SHP1, and PTP1B with IC50 values of 8.1-17.8 µM, and 1, 2, 5, 8-10, 12, and 13 showed antibacterial activity against six pathogens. Their structure-activity relationship is also discussed.


Assuntos
Alcaloides , Penicillium , Alcaloides/química , Antibacterianos/química , Dicroísmo Circular , Fungos/química , Estrutura Molecular , Penicillium/química
7.
Mar Drugs ; 20(1)2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35049933

RESUMO

Puniceusines A-N (1-14), 14 new isoquinoline alkaloids, were isolated from the extracts of a deep-sea-derived fungus, Aspergillus puniceus SCSIO z021. Their structures were elucidated by spectroscopic analyses. The absolute configuration of 9 was determined by ECD calculations, and the structures of 6 and 12 were further confirmed by a single-crystal X-ray diffraction analysis. Compounds 3-5 and 8-13 unprecedentedly contained an isoquinolinyl, a polysubstituted benzyl or a pyronyl at position C-7 of isoquinoline nucleus. Compounds 3 and 4 showed selective inhibitory activity against protein tyrosine phosphatase CD45 with IC50 values of 8.4 and 5.6 µM, respectively, 4 also had a moderate cytotoxicity towards human lung adenocarcinoma cell line H1975 with an IC50 value of 11.0 µM, and 14, which contained an active center, -C=N+, exhibited antibacterial activity. An analysis of the relationship between the structures, enzyme inhibitory activity and cytotoxicity of 1-14 revealed that the substituents at C-7 of the isoquinoline nucleus could greatly affect their bioactivity.


Assuntos
Alcaloides/farmacologia , Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Aspergillus , Isoquinolinas/farmacologia , Proteínas Tirosina Fosfatases/antagonistas & inibidores , Alcaloides/química , Animais , Antibacterianos/química , Antineoplásicos/química , Organismos Aquáticos , Linhagem Celular Tumoral/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Isoquinolinas/química , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana
8.
Mar Drugs ; 20(12)2022 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-36547883

RESUMO

Six new citreoviridins (citreoviridins J-O, 1-6) and twenty-two known compounds (7-28) were isolated from the deep-sea-derived Penicillium citreonigrum MCCC 3A00169. The structures of the new compounds were determined by spectroscopic methods, including the HRESIMS, NMR, ECD calculations, and dimolybdenum tetraacetate-induced CD (ICD) experiments. Citreoviridins J-O (1-6) are diastereomers of 6,7-epoxycitreoviridin with different chiral centers at C-2-C-7. Pyrenocine A (7), terrein (14), and citreoviridin (20) significantly induced apoptosis for HeLa cells with IC50 values of 5.4 µM, 11.3 µM, and 0.7 µM, respectively. To be specific, pyrenocine A could induce S phase arrest, while terrein and citreoviridin could obviously induce G0-G1 phase arrest. Citreoviridin could inhibit mTOR activity in HeLa cells.


Assuntos
Penicillium , Humanos , Células HeLa , Linhagem Celular Tumoral , Penicillium/química , Espectroscopia de Ressonância Magnética/métodos , Estrutura Molecular
9.
Mar Drugs ; 21(1)2022 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-36662191

RESUMO

Fucoidan is a sulfated algal polyanionic polysaccharide that possesses many biological activities. In this paper, a fucoidan (SHF) polysaccharide was extracted from Sargassum hemiphyllum collected in the South China Sea. The SHF, with a molecular weight of 1166.48 kDa (44.06%, w/w), consisted of glucose (32.68%, w/w), galactose (24.81%, w/w), fucose (20.75%, w/w), xylose (6.98%, w/w), mannose (2.76%, w/w), other neutral monosaccharides, and three uronic acids, including glucuronic acid (5.39%, w/w), mannuronic acid (1.76%, w/w), and guronuronic acid (1.76%, w/w). The SHF exhibited excellent immunostimulatory activity. An immunostimulating assay showed that SHF could significantly increase NO secretion in macrophage RAW 264.7 cells via upregulation of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) levels based on both gene expression and protein abundance. These results suggest that SHF isolated from Sargassum hemiphyllum has great potential to act as a health-boosting ingredient in the pharmaceutical and functional-food fields.


Assuntos
Sargassum , Sargassum/química , Polissacarídeos/química , Monossacarídeos/química , Macrófagos
10.
Mar Drugs ; 19(4)2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33923496

RESUMO

Ten new (1-10) and 26 known (11-36) compounds were isolated from Penicillium griseofulvum MCCC 3A00225, a deep sea-derived fungus. The structures of the new compounds were determined by detailed analysis of the NMR and HRESIMS spectroscopic data. The absolute configurations were established by X-ray crystallography, Marfey's method, and the ICD method. All isolates were tested for in vitro anti-food allergic bioactivities in immunoglobulin (Ig) E-mediated rat basophilic leukemia (RBL)-2H3 cells. Compound 13 significantly decreased the degranulation release with an IC50 value of 60.3 µM, compared to that of 91.6 µM of the positive control, loratadine.


Assuntos
Antialérgicos/farmacologia , Basófilos/efeitos dos fármacos , Degranulação Celular/efeitos dos fármacos , Hipersensibilidade Alimentar/tratamento farmacológico , Penicillium/metabolismo , Animais , Antialérgicos/isolamento & purificação , Basófilos/imunologia , Linhagem Celular Tumoral , Hipersensibilidade Alimentar/imunologia , Sedimentos Geológicos/microbiologia , Imunoglobulina E/imunologia , Estrutura Molecular , Ratos , Relação Estrutura-Atividade
11.
Bioorg Chem ; 105: 104349, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33074115

RESUMO

Ten new C9 polyketides (asperochratides A-J, 1-10) and 14 known miscellaneous compounds (11-24) were isolated from the deep-sea-derived fungus Aspergillus ochraceus. Structures of the new compounds were elucidated by extensive spectroscopic analyses, modified Mosher's method, Mo2(OAc)4 induced circular dichroism (ICD) experiments, and ECD calculations. Structurally, compounds 1-11 and 16-18 share the same polyketide origin of the skeleton and belong to aspyrone co-metabolites. All isolates were tested for cytotoxic, anti-food allergic, anti-H1N1 virus, anti-microbe, and anti-inflammatory activities in vitro. Results showed that compounds 5-8 and 13-17 exerted significant cytotoxic effects on BV-2 cell line, and compound 16 showed the potential of anti-inflammatory activities.


Assuntos
Anti-Inflamatórios/química , Antineoplásicos/química , Aspergillus ochraceus/química , Misturas Complexas/química , Policetídeos/química , Água do Mar/microbiologia , Anti-Inflamatórios/farmacologia , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Misturas Complexas/farmacologia , Avaliação Pré-Clínica de Medicamentos , Humanos , Modelos Moleculares , Conformação Molecular , Óxido Nítrico/metabolismo , Policetídeos/farmacologia
12.
Chem Biodivers ; 17(6): e2000158, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32259395

RESUMO

A unique polyketide cladosporactone A along with eight known compounds were isolated from the deep-sea-derived Cladosporium cladosporioides. The structure of cladosporactone A was established by spectroscopic analyses, and the absolute configuration was clarified by the theoretical ECD calculation. Cladosporactone A is the first member of polyketide with the 7-methylisochromen-3-one skeleton.


Assuntos
Cladosporium/química , Policetídeos/química , Água do Mar/microbiologia , Dicroísmo Circular , Cladosporium/isolamento & purificação , Cladosporium/metabolismo , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Conformação Molecular , Policetídeos/isolamento & purificação
13.
Pharmazie ; 75(6): 275-278, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32539925

RESUMO

MicroRNAs (miRNAs) play important roles in the progression of acute lung injury (ALI). So far, little is known about the role of miR-520c-3p in ALI. In this study, the mechanism of the occurrence and development of ALI was explored. We firstly found that miR-520c-3p could inhibit the expression of NLRC5. A549 cells were treated with lipopolysaccharide (LPS) in vitro to simulate ALI cells and inducing ALI model mice. Moreover, miR-520c-3p overexpression enhanced the viability of damaged cells, inhibited LPS-induced apoptosis, and decreased LPS-induced IL-1ß, IL-6 and TNF-α. In addition, the NLRC5 was a direct target of miR-520c-3p. And NLRC5 partially aggravated inflammation injury. In conclusion, miR-520c-3p alleviates LPS-induced inflammatory injury via regulating NLRC5.


Assuntos
Lesão Pulmonar Aguda/genética , Inflamação/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , MicroRNAs/genética , Células A549 , Lesão Pulmonar Aguda/fisiopatologia , Animais , Sobrevivência Celular/genética , Modelos Animais de Doenças , Humanos , Inflamação/patologia , Lipopolissacarídeos , Masculino , Camundongos , Camundongos Endogâmicos C57BL
14.
Int J Cancer ; 145(5): 1334-1345, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-30786019

RESUMO

Oncogenic KRAS is considered a promising target for anti-cancer therapy. However, direct pharmacological strategies targeting KRAS-driven cancers remained unavailable. The prenyl-binding protein PDEδ, a transporter of KRAS, has been identified as a potential target for pharmacological inhibitor by selectively binding to its prenyl-binding pocket, impairing oncogenic KRAS signaling pathway. Here, we discovered a novel PDEδ inhibitor (E)-N'-((3-(tert-butyl)-2-hydroxy-6,7,8,9-tetrahydrodibenzo[b,dfuran-1-yl)methylene)-2,4-dihydroxybenzohydrazide(NHTD) by using a high-throughput docking-based virtual screening approach. In vitro and in vivo studies demonstrated that NHTD suppressed proliferation, induced apoptosis and inhibited oncogenic K-RAS signaling pathways by disrupting KRAS-PDEδ interaction in nonsmall cell lung cancer (NSCLC) harboring KRAS mutations. NHTD redistributed the localization of KRAS to endomembranes by targeting the prenyl-binding pocket of PDEδ and exhibited the suppression of abnormal KRAS function. Importantly, NHTD prevented tumor growth in xenograft and KRAS mutant mouse model, which presents an effective strategy targeting KRAS-driven cancer.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Nucleotídeo Cíclico Fosfodiesterase do Tipo 6/antagonistas & inibidores , Hidrazonas/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Proteínas Proto-Oncogênicas p21(ras)/antagonistas & inibidores , Proteínas Proto-Oncogênicas p21(ras)/genética , Células A549 , Animais , Benzofuranos/farmacocinética , Benzofuranos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/enzimologia , Carcinoma Pulmonar de Células não Pequenas/genética , Linhagem Celular Tumoral , Nucleotídeo Cíclico Fosfodiesterase do Tipo 6/metabolismo , Feminino , Humanos , Hidrazonas/farmacocinética , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/genética , Masculino , Camundongos , Camundongos Nus , Células NIH 3T3 , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Mar Drugs ; 16(12)2018 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-30572615

RESUMO

Five new oxygenated sesquiterpenes, molestins A⁻D (1, 3⁻5) and epi-gibberodione (2), three new cyclopentenone derivatives, ent-sinulolides C, D, and F ((+)-9⁻(+)-11), one new butenolide derivative, ent-sinulolide H ((+)-13), and one new cembranolide, molestin E (14), together with 14 known related metabolites (6⁻8, (⁻)-9⁻(⁻)-11, (±)-12, (⁻)-13, 15⁻19) were isolated from the Paracel Islands soft coral Sinularia cf. molesta. The structures and absolute configurations were elucidated based on comprehensive spectroscopic analyses, quantum chemical calculations, and comparison with the literature data. Compound 5 is the first example of a norsesquiterpene with a de-isopropyl guaiane skeleton isolated from the genus Sinularia. Molestin E (14) exhibited cytotoxicities against HeLa and HCT-116 cell lines with IC50 values of 5.26 and 8.37 µM, respectively. Compounds 4, 5, and 8 showed significant inhibitory activities against protein tyrosine phosphatase 1B (PTP1B) with IC50 values of 218, 344, and 1.24 µM, respectively.


Assuntos
Antozoários/química , Citotoxinas/química , Sesquiterpenos/química , 4-Butirolactona/análogos & derivados , 4-Butirolactona/química , 4-Butirolactona/isolamento & purificação , 4-Butirolactona/farmacologia , Animais , Linhagem Celular Tumoral , Ciclopentanos/química , Ciclopentanos/isolamento & purificação , Ciclopentanos/farmacologia , Células HCT116 , Células HeLa , Humanos , Conformação Molecular , Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/farmacologia
16.
Cell Mol Neurobiol ; 37(4): 753-762, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27488855

RESUMO

Ischemia-induced brain damage leads to apoptosis like delayed neuronal death in selectively vulnerable regions, which could further result in irreversible damages. Previous studies have demonstrated that neurons in the CA1 area of hippocampus are particularly sensitive to ischemic damage. Atorvastatin (ATV) has been reported to attenuate cognitive deficits after stroke, but precise mechanism for neuroprotection remains unknown. Therefore, the aims of this study were to investigate the neuroprotective mechanisms of ATV against ischemic brain injury induced by cerebral ischemia reperfusion. In this study, four-vessel occlusion model was established in rats with cerebral ischemia. Rats were divided into five groups: sham group, I/R group, I/R+ATV group, I/R+ATV+LY, and I/R+SP600125 group. Cresyl violet staining was carried out to examine the neuronal death of hippocampal CA1 region. Immunoblotting was used to detect the expression of the related proteins. Results showed that ATV significantly protected hippocampal CA1 pyramidal neurons against cerebral I/R. ATV could increase the phosphorylation of protein kinase B (Akt1) and nNOS, diminished the phosphorylation of JNK3 and c-Jun, and further inhibited the activation of caspase-3. Whereas, all of the aforementioned effects of ATV were reversed by LY294002 (an inhibitor of Akt1). Furthermore, pretreatment with SP600125 (an inhibitor of JNK) diminished the phosphorylation of JNK3 and c-Jun, and further inhibited the activation of caspase-3 after cerebral I/R. Taken together, our results implied that Akt-mediated phosphorylation of nNOS is involved in the neuroprotection of ATV against ischemic brain injury via suppressing JNK3 signaling pathway that provide a new experimental foundation for stroke therapy.


Assuntos
Atorvastatina/farmacologia , Isquemia Encefálica/tratamento farmacológico , Hipocampo/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Traumatismo por Reperfusão/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Atorvastatina/metabolismo , Isquemia Encefálica/metabolismo , Hipocampo/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno , Neurônios/metabolismo , Óxido Nítrico Sintase Tipo I/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos Sprague-Dawley , Traumatismo por Reperfusão/metabolismo
17.
Epidemiology ; 26(2): 192-203, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25563432

RESUMO

BACKGROUND: Cosmic radiation and circadian disruption are potential reproductive hazards for flight attendants. METHODS: Flight attendants from 3 US airlines in 3 cities were interviewed for pregnancy histories and lifestyle, medical, and occupational covariates. We assessed cosmic radiation and circadian disruption from company records of 2 million individual flights. Using Cox regression models, we compared respondents (1) by levels of flight exposures and (2) to teachers from the same cities, to evaluate whether these exposures were associated with miscarriage. RESULTS: Of 2654 women interviewed (2273 flight attendants and 381 teachers), 958 pregnancies among 764 women met study criteria. A hypothetical pregnant flight attendant with median first-trimester exposures flew 130 hours in 53 flight segments, crossed 34 time zones, and flew 15 hours during her home-base sleep hours (10 pm-8 am), incurring 0.13 mGy absorbed dose (0.36 mSv effective dose) of cosmic radiation. About 2% of flight attendant pregnancies were likely exposed to a solar particle event, but doses varied widely. Analyses suggested that cosmic radiation exposure of 0.1 mGy or more may be associated with increased risk of miscarriage in weeks 9-13 (odds ratio = 1.7 [95% confidence interval = 0.95-3.2]). Risk of a first-trimester miscarriage with 15 hours or more of flying during home-base sleep hours was increased (1.5 [1.1-2.2]), as was risk with high physical job demands (2.5 [1.5-4.2]). Miscarriage risk was not increased among flight attendants compared with teachers. CONCLUSIONS: Miscarriage was associated with flight attendant work during sleep hours and high physical job demands and may be associated with cosmic radiation exposure.


Assuntos
Aborto Espontâneo/etiologia , Transtornos Cronobiológicos/complicações , Radiação Cósmica/efeitos adversos , Doenças Profissionais/etiologia , Exposição Ocupacional/efeitos adversos , Aborto Espontâneo/epidemiologia , Adulto , Medicina Aeroespacial , Transtornos Cronobiológicos/epidemiologia , Docentes , Feminino , Humanos , Pessoa de Meia-Idade , Doenças Profissionais/epidemiologia , Razão de Chances , Gravidez , Modelos de Riscos Proporcionais , Fatores de Risco , Autorrelato , Estados Unidos/epidemiologia
18.
Opt Express ; 22(20): 24202-16, 2014 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-25321995

RESUMO

We propose a novel coupled resonator optical waveguide (CROW) structure that is made up of a waveguide loop. We theoretically investigate the forbidden band and conduction band conditions in an infinite periodic lattice. We also discuss the reflection- and transmission- spectra, group delay in finite periodic structures. Light has a larger group delay at the band edge in a periodic structure. The flat band pass filter and flat-top group delay can be realized in a non-periodic structure. Scattering matrix method is used to calculate the effects of waveguide loss on the optical characteristics of these structures. We also introduce a tunable coupling loop waveguide to compensate for the fabrication variations since the coupling coefficient of the directional coupler in the loop waveguide is a critical factor in determining the characteristics of a loop CROW. The loop CROW structure is suitable for a wide range of applications such as band pass filters, high Q microcavity, and optical buffers and so on.

19.
Am J Ind Med ; 57(4): 412-24, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24375784

RESUMO

OBJECTIVES: We examined health outcomes among 34,494 workers employed at a microelectronics and business machine facility 1969-2001. METHODS: Standardized mortality ratio (SMR) and standardized incidence ratios were used to evaluate health outcomes in the cohort and Cox regression modeling to evaluate relations between scores for occupational exposures and outcomes of a priori interest. RESULTS: Just over 17% of the cohort (5,966 people) had died through 2009. All cause, all cancer, and many cause-specific SMRs showed statistically significant deficits. In hourly males, SMRs were significantly elevated for non-Hodgkin's lymphoma and rectal cancer. Salaried males had excess testicular cancer incidence. Pleural cancer and mesothelioma excesses were observed in workers hired before 1969, but no available records substantiate use of asbestos in manufacturing processes. A positive, statistically significant relation was observed between exposure scores for tetrachloroethylene and nervous system diseases. CONCLUSIONS: Few significant exposure-outcome relations were observed, but risks from occupational exposures cannot be ruled out due to data limitations and the relative youth of the cohort.


Assuntos
Computadores , Eletrônica , Neoplasias/epidemiologia , Doenças do Sistema Nervoso/epidemiologia , Doenças Profissionais/epidemiologia , Exposição Ocupacional/estatística & dados numéricos , Tetracloroetileno/efeitos adversos , Adulto , Amianto/efeitos adversos , Causas de Morte , Estudos de Coortes , Feminino , Humanos , Incidência , Linfoma não Hodgkin/mortalidade , Masculino , Mesotelioma/epidemiologia , Pessoa de Meia-Idade , Neoplasias/mortalidade , Doenças Profissionais/mortalidade , Neoplasias Pleurais/epidemiologia , Modelos de Riscos Proporcionais , Neoplasias Retais/mortalidade , Análise de Regressão , Estudos Retrospectivos , Neoplasias Testiculares/epidemiologia
20.
Aviat Space Environ Med ; 85(8): 828-32, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25199125

RESUMO

INTRODUCTION: Research has suggested that work as a flight attendant may be related to increased risk for reproductive health effects. Air cabin exposures that may influence reproductive health include radiation dose from galactic cosmic radiation and solar particle events. This paper describes the assessment of radiation dose accrued during solar particle events as part of a reproductive health study of flight attendants. METHODS: Solar storm data were obtained from the National Oceanic and Atmospheric Administration Space Weather Prediction Center list of solar proton events affecting the Earth environment to ascertain storms relevant to the two study periods (1992-1996 and 1999-2001). Radiation dose from exposure to solar energetic particles was estimated using the NAIRAS model in conjunction with galactic cosmic radiation dose calculated using the CARI-6P computer program. RESULTS: Seven solar particle events were determined to have potential for significant radiation exposure, two in the first study period and five in the second study period, and over-lapped with 24,807 flight segments. Absorbed (and effective) flight segment doses averaged 6.5 µGy (18 µSv) and 3.1 µGy (8.3 µSv) for the first and second study periods, respectively. Maximum doses were as high as 440 µGy (1.2 mSv) and 20 flight segments had doses greater than 190 µGy (0.5 mSv). DISCUSSION: During solar particle events, a pregnant flight attendant could potentially exceed the equivalent dose limit to the conceptus of 0.5 mSv in a month recommended by the National Council on Radiation Protection and Measurements.


Assuntos
Aeronaves , Radiação Cósmica/efeitos adversos , Exposição Ocupacional/efeitos adversos , Doses de Radiação , Adolescente , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Gravidez , Fatores de Risco , Atividade Solar
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