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1.
Phytopathology ; 114(6): 1263-1275, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38105219

RESUMO

Leaves of Welsh onion (Allium fistulosum) are subject to various fungal diseases such as anthracnose (Colletotrichum species) and Stemphylium leaf blight (Stemphylium vesicarium). These diseases are the main biotic limitations to Welsh onion production in northern Taiwan. From 2018 to 2020, anthracnose symptoms were observed throughout Welsh onion fields in northern Taiwan, mainly the Sanxing area. In total, 33 strains of Colletotrichum species were isolated from diseased leaves, and major causative agents were identified based on a multilocus phylogenetic analysis using four genomic regions (act, tub2, gapdh, and internal transcribed spacer). Based on this phylogeny, Colletotrichum species causing anthracnose of Welsh onion were identified as C. spaethianum (C. spaethianum species complex) and C. circinans (C. dematium species complex) in the Sanxing area, northern Taiwan. To determine and compare the pathogenicity of each species, representative fungal strains of each species were inoculated on the cultivar 'Siao-Lyu' by spraying spore suspension onto the leaf surface. Welsh onion plants were susceptible to both species, but disease incidence and severity were higher in C. spaethianum. In total, 31 fungicides were tested to determine their efficacy in reducing mycelial growth and conidial germination of representative strains of C. spaethianum and C. circinans under laboratory conditions. Five fungicides-fluazinam, metiram, mancozeb, thiram, and dithianon-effectively reduced mycelial growth and spore germination in both C. spaethianum and C. circinans. In contrast, difenoconazole and trifloxystrobin + tebuconazole, which are commonly used in Welsh onion production in northern Taiwan, mainly the Sanxing area, were ineffective. These results serve as valuable insights for growers, enabling them to identify and address the emergence of anthracnose caused by C. spaethianum and C. circinans of Welsh onion, employing fungicides with diverse modes of action. The findings of this study support sustainable management of anthracnose in Sanxing, northern Taiwan, although further field tests of the fungicides are warranted.


Assuntos
Colletotrichum , Cebolas , Filogenia , Doenças das Plantas , Colletotrichum/fisiologia , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Taiwan , Cebolas/microbiologia , Folhas de Planta/microbiologia , Fungicidas Industriais/farmacologia
2.
BMC Public Health ; 24(1): 551, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38388363

RESUMO

During the COVID-19 pandemic, Taiwan has implemented strict border controls and community spread prevention measures. As part of these efforts, the government also implemented measures for public transportation. In Taiwan, there are two primary public transportation systems: Taiwan Railways (TR) is commonly utilized for local travel, while the Taiwan High-Speed Rail (THSR) is preferred for business trips and long-distance journeys due to its higher speed. In this study, we examined the impact of these disease prevention measures on the number of passengers and duration of stay in two major public transportation systems during the first community outbreak from April 29th to May 29th, 2021. Using data from a local telecommunications company, our study observed an expected decrease in the number of passengers after the cancellation of non-reserved seats at both TR and THSR stations across all 19 cities in the main island of Taiwan. Surprisingly, however, the duration of stay in some of the cities unexpectedly increased, especially at THSR stations. This unanticipated rise in the duration of stay has the potential to elevate contact probability among passengers and, consequently, the transmission rate. Our analysis shows that intervention policies may result in unforeseen outcomes, highlighting the crucial role of human mobility data as a real-time reference for policymakers. It enables them to monitor the impact of disease prevention measures and facilitates informed, data-driven decision-making.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , COVID-19/prevenção & controle , Taiwan/epidemiologia , Pandemias/prevenção & controle , Surtos de Doenças/prevenção & controle , Meios de Transporte
3.
J Am Chem Soc ; 145(1): 516-526, 2023 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-36562565

RESUMO

Organic molecules having emission in the NIR(II) region are emergent and receiving enormous attention. Unfortunately, attaining accountable organic emission intensity around the NIR(II) region is hampered by the dominant internal conversion operated by the energy gap law, where the emission energy gap and the associated internal reorganization energy λint play key roles. Up to the current stage, the majority of the reported organic NIR(II) emitters belong to those polymethines terminated by two symmetric chromophores. Such a design has proved to have a small λint that greatly suppresses the internal conversion. However, the imposition of symmetric chromophores is stringent, limiting further development of organic NIR(II) dyes in diversity and versatility. Here, we propose a new concept where as far as the emissive state of the any asymmetric polymethines contains more or less equally transition density between two terminated chromophores, λint can be as small as that of the symmetric polymethines. To prove the concept, we synthesize a series of new polymethines terminated by xanthen-9-yl-benzoic acid and 2,4-diphenylthiopyrylium derivatives, yielding AJBF1112 and AEBF1119 that reveal emission peak wavelength at 1112 and 1119 nm, respectively. The quantum yield is higher than all synthesized symmetric polymethines of 2,4-diphenylthiopyrylium derivatives (SC1162, 1182, 1185, and 1230) in this study. λint were calculated to be as small as 6.2 and 7.3 kcal/mol for AJBF1112 and AEBF1119, respectively, proving the concept. AEBF1119 was further prepared as a polymer dot to demonstrate its in vitro specific cellular imaging and in vivo tumor/bone targeting in the NIR(II) region.


Assuntos
Corantes Fluorescentes , Indóis
4.
Curr Issues Mol Biol ; 44(4): 1552-1563, 2022 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-35723364

RESUMO

Personalized treatments based on the genetic profiles of tumors can simultaneously optimize efficacy and minimize toxicity, which is beneficial for improving patient outcomes. This study aimed to integrate gene alterations associated with predictive and prognostic outcomes in patients with metastatic colorectal cancer (mCRC) with polymerase chain reaction (PCR) and in-house next-generation sequencing (NGS) to detect KRAS, NRAS, and BRAF mutations. In the present study, 41 patients with mCRC were assessed between August 2017 and June 2019 at a single institution. The overall concordance between NGS and PCR results for detecting KRAS, NRAS, and BRAF mutations was considerably high (87.8-92.7%), with only 15 discrepant results between PCR and NGS. Our companion diagnostic test analyzes KRAS, NRAS, and BRAF as a panel of CRC molecular targets; therefore, it has the advantages of requiring fewer specimens and being more time and cost efficient than conventional testing for separate analyses, allowing for the simultaneous analysis of multiple genes.

5.
Plant Dis ; 106(12): 3187-3197, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35581907

RESUMO

Rice blast caused by Magnaporthe oryzae is a dangerous threat to rice production and food security worldwide. Breeding and proper deployment of resistant varieties are effective and environmentally friendly strategies to manage this notorious disease. However, a highly dynamic and quickly evolved rice blast pathogen population in the field has made disease control with resistance germplasms more challenging. Therefore, continued monitoring of pathogen dynamics and application of effective resistance varieties are critical tasks to prolong or sustain field resistance. Here, we report a team project that involved evaluation of rice blast resistance genes and surveillance of M. oryzae field populations in Taiwan. A set of International Rice Research Institute-bred blast-resistant lines (IRBLs) carrying single blast resistance genes was utilized to monitor the field effectiveness of rice blast resistance. Resistance genes such as Ptr (formerly Pita2) and Pi9 exhibited the best and most durable resistance against the rice blast fungus population in Taiwan. Interestingly, line IRBLb-B harboring the Pib gene with good field protection has recently shown susceptible lesions in some locations. To dissect the genotypic features of virulent isolates against the Pib resistance gene, M. oryzae isolates were collected and analyzed. Screening of the AvrPib locus revealed that the majority of field isolates still maintained the wild-type AvrPib status but eight virulent genotypes were found. Pot3 insertion appeared to be a major way to disrupt the AvrPib avirulence function. Interestingly, a novel AvrPib double-allele genotype among virulent isolates was first identified. Pot2 repetitive element-based polymerase chain reaction (rep-PCR) fingerprinting analysis indicated that mutation events may occur independently among different lineages in different geographic locations of Taiwan. This study provides our surveillance experience of rice blast disease and serves as the foundation to sustain rice production.


Assuntos
Magnaporthe , Oryza , Magnaporthe/genética , Doenças das Plantas/microbiologia , Oryza/genética , Oryza/microbiologia , Taiwan , Melhoramento Vegetal
6.
Plant Dis ; 105(12): 4121-4131, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34213966

RESUMO

Welsh onion (Allium fistulosum L.) is one of the main and oldest vegetable crops grown in Taiwan. A severe epidemic of leaf blight in Welsh onion caused by a Stemphylium-like pathogen was found in Sanxing, Taiwan, from 2018 to 2020. However, correct species identification, biology, and control of Stemphylium leaf blight (SLB) of Welsh onion are not well-established. Therefore, the main objective of this study was to investigate the causal agent of SLB in Sanxing and evaluate the in vitro sensitivity of Stemphylium-like pathogen to commonly used fungicides. A phylogenetic analysis based on combining the internal transcribed spacer (ITS) region and glyceraldedyhe-3-phosphate dehydrogenase (gapdh) and calmodulin (cmdA) gene sequences together with morphological features identified that S. vesicarium is associated with SLB in Sanxing. When inoculated onto Welsh onion leaves, the isolates caused symptoms identical to those observed in the field; therefore, S. vesicarium was reisolated and Koch's postulates were confirmed. We observed a higher incidence of SLB symptoms on the oldest leaves compared with younger leaves. The maximum and minimum temperatures for in vitro mycelial growth and conidial germination (%) of S. vesicarium were 20 to 30°C and 5°C, respectively. Sixteen fungicides were tested for their effectiveness to reduce the mycelial growth and conidial germination of S. vesicarium in vitro. Boscalid plus pyraclostrobin, fluopyram, fluxapyroxad, and fluxapyroxad plus pyraclostrobin were highly effective at reducing mycelial growth and conidial germination in S. vesicarium. However, strobilurin fungicides (azoxystrobin and kresoxim-methyl) commonly used in Welsh onion production in Sanxing were ineffective. This study discusses the emergence of SLB caused by S. vesicarium in the foliar disease complex affecting Welsh onion and the management of the disease using fungicides with different modes of action in Taiwan. The research will support the sustainable management of SLB in Sanxing, Taiwan; however, further field assessments of the fungicides are warranted.


Assuntos
Allium , Ascomicetos , Ascomicetos/genética , Cebolas , Filogenia , Taiwan
7.
Phytopathology ; 110(12): 1934-1945, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32689901

RESUMO

Bakanae disease in rice can cause abnormal elongation of the stem and leaves, development of adventitious roots, a larger leaf angle, and even death. Little is known about the infection, colonization, and distribution of Fusarium fujikuroi in rice plants across different growth stages. In this study, microscopic observation and quantitative real-time PCR were combined to investigate the pathogenesis of bakanae, using artificially inoculated seedlings of a susceptible rice cultivar, Zerawchanica karatals (ZK), a resistant cultivar, Tainung 67 (TNG67), naturally infected adult field plants (cultivars Kaohsiung 139, Taikeng 2, and Tainan 11), and an F. fujikuroi isolate expressing green fluorescent protein. In rice seedlings, F. fujikuroi hyphae were found to directly penetrate the epidermis of basal stems and roots, then extend inter- and intracellularly to invade the vascular bundles. Occlusion of vascular bundles and radial hyphal expansion from vascular bundles to surrounding parenchyma were observed in adult plants. Analysis of consecutive 3-cm segments of the whole plant revealed that F. fujikuroi was largely confined to the embryo, basal stem, and basal roots in seedlings, and distributed unevenly in the lower aerial parts (including nodes and internodes) of adult plants. The elongation and development of adventitious roots did not necessarily correlate with the amount of F. fujikuroi in diseased plants. Treatment of rice seeds with gibberellic acid-3 (GA3) at 0.5 mg/liter resulted in significantly more elongation of ZK than TNG67 seedlings, suggesting that the susceptibility of ZK to bakanae is associated with its higher sensitivity to GA3.


Assuntos
Fusarium , Oryza , Doenças das Plantas , Plântula
8.
J Cell Mol Med ; 22(11): 5573-5582, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30134043

RESUMO

Acute hepatic injury caused by inflammatory liver disease is associated with high mortality. This study examined the role of caveolin-1 (Cav-1) in lipopolysaccharide (LPS) and D-galactosamine (GalN)-induced fulminant hepatic injury in wild type and Cav-1-null (Cav-1-/- ) mice. Hepatic Cav-1 expression was induced post-LPS/GalN treatment in wild-type mice. LPS/GalN-treated Cav-1-/- mice showed reduced lethality and markedly attenuated liver damage, neutrophil infiltration and hepatocyte apoptosis as compared to wild-type mice. Cav-1 deletion significantly reduced LPS/GalN-induced caspase-3, caspase-8 and caspase-9 activation and pro-inflammatory cytokine and chemokine expression. Additionally, Cav-1-/- mice showed suppressed expression of Toll-like receptor 4 (TLR4) and CD14 in Kupffer cells and reduced expression of vascular cell adhesion molecule 1 and intercellular adhesion molecule 1 in liver cells. Cav-1 deletion impeded LPS/GalN-induced inducible nitric oxide synthase expression and nitric oxide production and hindered nuclear factor-κB (NF-κB) activation. Taken together, Cav-1 regulated the expression of mediators that govern LPS-induced inflammatory signalling in mouse liver. Thus, deletion of Cav-1 suppressed the inflammatory response mediated by the LPS-CD14-TLR4-NF-κb pathway and alleviated acute liver injury in mice.


Assuntos
Caveolina 1/genética , Doença Hepática Induzida por Substâncias e Drogas/genética , Inflamação/genética , Fígado/efeitos dos fármacos , Animais , Apoptose/genética , Doença Hepática Induzida por Substâncias e Drogas/patologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Inflamação/induzido quimicamente , Inflamação/patologia , Molécula 1 de Adesão Intercelular/genética , Células de Kupffer/efeitos dos fármacos , Células de Kupffer/metabolismo , Receptores de Lipopolissacarídeos/genética , Lipopolissacarídeos/toxicidade , Fígado/lesões , Fígado/metabolismo , Fígado/patologia , Camundongos , NF-kappa B/genética , Infiltração de Neutrófilos/genética , Óxido Nítrico Sintase Tipo II/genética , Transdução de Sinais/genética , Receptor 4 Toll-Like/genética , Fator de Transcrição RelA/genética
9.
Epilepsia ; 58(8): 1423-1429, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28682459

RESUMO

OBJECTIVE: The medium-chain triglyceride (MCT) ketogenic diet contains both octanoic (C8) and decanoic (C10) acids. The diet is an effective treatment for pharmacoresistant epilepsy. Although the exact mechanism for its efficacy is not known, it is emerging that C10, but not C8, interacts with targets that can explain antiseizure effects, for example, peroxisome proliferator-activated receptor-γ (eliciting mitochondrial biogenesis and increased antioxidant status) and the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor. For such effects to occur, significant concentrations of C10 are likely to be required in the brain. METHODS: To investigate how this might occur, we measured the ß-oxidation rate of 13 C-labeled C8 and C10 in neuronal SH-SY5Y cells using isotope-ratio mass spectrometry. The effects of carnitine palmitoyltransferase I (CPT1) inhibition, with the CPT1 inhibitor etomoxir, on C8 and C10 ß-oxidation were also investigated. RESULTS: Both fatty acids were catabolized, as judged by 13 CO2 release. However, C10 was ß-oxidized at a significantly lower rate, 20% that of C8. This difference was explained by a clear dependence of C10 on CPT1 activity, which is low in neurons, whereas 66% of C8 ß-oxidation was independent of CPT1. In addition, C10 ß-oxidation was decreased further in the presence of C8. SIGNIFICANCE: It is concluded that, because CPT1 is poorly expressed in the brain, C10 is relatively spared from ß-oxidation and can accumulate. This is further facilitated by the presence of C8 in the MCT ketogenic diet, which has a sparing effect upon C10 ß-oxidation.


Assuntos
Caprilatos/metabolismo , Dieta Cetogênica , Caprilatos/farmacologia , Isótopos de Carbono/metabolismo , Carnitina O-Palmitoiltransferase/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ácidos Decanoicos/metabolismo , Ácidos Decanoicos/farmacologia , Glucose/metabolismo , Humanos , Neuroblastoma/patologia , Oxirredução/efeitos dos fármacos
10.
Eur J Nutr ; 55(6): 2031-43, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26264388

RESUMO

PURPOSE: Both endoplasmic reticulum stress (ER stress) and autophagy are essential for the response of the protein quality control system to cellular stresses. This study investigated the influence of the duration of a high-fat diet (HFD) in mice on tissue-specific cellular responses, specifically with regard to the role of autophagy and ER stress. METHODS: Male mice aged 6-7 weeks were fed ad libitum with a standard chow diet or with a HFD for 2, 4, 8, or 16 weeks. RESULTS: The HFD progressively increased mean body weight and induced tissue hypertrophy. The expression of PERK was suppressed in the liver after 16 weeks of the HFD and in the heart after 8 weeks of the HFD. Procaspase 12 and its activated form were induced in the liver with the HFD after 2 weeks, but not in the heart over the 16-week period. The activation of hepatic AMPK was elevated following 4 weeks of the HFD, but was inhibited after 16 weeks of the HFD. The ratio of LC3II to LC3I in the liver did not increase except in those mice fed the HFD for 16 weeks. The expression of AMPK and LC3 in the heart did not change over the entire 16 weeks of feeding the HFD. Cleaved PARP was increased in the liver and heart of mice receiving the HFD for 8 weeks. CONCLUSIONS: This study provides evidence that a HFD affects the cellular protein quality control processes responsible for metabolic disorder in a tissue- and duration-dependent manner.


Assuntos
Autofagia , Dieta Hiperlipídica/efeitos adversos , Estresse do Retículo Endoplasmático , Fígado/patologia , Miocárdio/patologia , Adenilato Quinase/metabolismo , Animais , Modelos Animais de Doenças , Dislipidemias/sangue , Dislipidemias/etiologia , Dislipidemias/patologia , Hiperglicemia/sangue , Hiperglicemia/etiologia , Hiperglicemia/patologia , Hipertrofia/etiologia , Hipertrofia/patologia , Fígado/citologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos , Proteínas Associadas aos Microtúbulos/metabolismo , Miocárdio/citologia , Obesidade/etiologia , Obesidade/patologia , Fatores de Tempo , Triglicerídeos/metabolismo , eIF-2 Quinase/metabolismo
11.
Phytopathology ; 106(6): 624-35, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26882848

RESUMO

The rice disease bakanae, caused by Fusarium fujikuroi Nirenberg, has been present in Taiwan for over a century. To better understand the genetic diversity and structure of F. fujikuroi, a set of 16 polymorphic simple sequence repeat (SSR) markers were newly developed and used to analyze 637 F. fujikuroi isolates collected in 14 cities or counties around Taiwan from 1996 to 2013. On the basis of Bayesian clustering, the isolates were classified into four highly differentiated clusters: cluster B likely derived from the more widespread and genetically diversified clusters A or C, and cluster D was restricted to four cities or counties and may have been introduced from unknown sources genetically distinct from clusters A, B, and C. The coexistence of both mating types (MAT1-1:MAT1-2 = 1:1.88) and the highly diversified vegetative compatibility groups (VCG) (16 VCG among the 21 assessed isolates) suggest the likelihood of sexual reproduction in the field. However, the biased mating type ratios and linkage disequilibrium in the population suggest nonrandom mating between individuals. A significant pattern of isolation by distance was also detected, which implies a geographical restricted gene flow and low dissemination ability of F. fujikuroi. Evaluation of 24 representative isolates on eight rice varieties revealed differential levels of virulence, however no clear pattern of specific variety x isolate interaction was observed. Investigations of the differences in virulence and fungicide sensitivity between 8 early isolates (1998 and 2002) and 52 recent isolates (2012) indicate the evolution of increased resistance to the fungicide prochloraz in F. fujikuroi in Taiwan.


Assuntos
Farmacorresistência Fúngica , Fungicidas Industriais/farmacologia , Fusarium/efeitos dos fármacos , Fusarium/genética , DNA Fúngico/genética , Fusarium/patogenicidade , Marcadores Genéticos , Variação Genética , Genoma Fúngico , Desequilíbrio de Ligação , Repetições de Microssatélites , Taiwan , Virulência
12.
Arch Psychiatr Nurs ; 30(2): 237-43, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26992877

RESUMO

This study proposes and evaluates a model of depression that concerns the role of burden and cognitive appraisal as mediators or moderators of outcomes among stroke survivor caregivers. A total of 105 informal caregivers of stroke survivor completed the self-report measures of Caregiver Burden Inventory, Center for Epidemiologic Studies Depression Scale, and Cognitive Impact of Appraisal Scale. The Glasgow Coma Scale and Barthel Index were used by the researcher to examine the physical functional status of the survivor. Partial least squares (PLS) path modeling was used to estimate the parameters of a depression model that included mediating or moderating effects. The model shows that burden and impact of cognitive appraisal have a significant direct and indirect impact on depression, while survivor physical functional status does not have a direct impact. The model also demonstrates that burden and impact of cognitive appraisal separately play a mediating role between survivor physical functional status and caregiver depression. In addition, cognitive appraisal has a moderating influence on the relationship between burden and depression. Overall, survivor physical functional status, burden, and cognitive appraisal were the predictors of caregiver depression, explaining 47.1% of the variance. This study has shown that burden and cognitive appraisal are mediators that more fully explain the relationship between patient severity and caregiver depression.


Assuntos
Cuidadores/psicologia , Cognição , Depressão/psicologia , Acidente Vascular Cerebral/enfermagem , Sobreviventes , Adaptação Psicológica , Adulto , Idoso , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Psicológicos , Índice de Gravidade de Doença
13.
J Biomed Sci ; 22: 31, 2015 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-25971314

RESUMO

BACKGROUND: Adenoviral vector is an efficient tool for gene transfer. Protein expression is regulated by a number of factors, but the regulation by gene copy number remains to be investigated further. RESULTS: Assessed by flow cytometry, we demonstrated a significant linear correlation between average fluorescence intensity of green fluorescent protein (GFP) and a wide range of multiplicity of infection (MOI), spanning from 0.01 to 200. Average GFP intensity was calculated by mean fluorescence intensity (MFI) × percentage of infection (POI) (MFI × POI) and the correlation was observed in cells transduced with GFP-expressing adenoviral vector driven either by a cytomegalovirus (CMV) promoter for 3 to 6 h or by a human phosphoglycerate kinase (PGK) promoter for 18 to 24 h. Factors impacting this linear correlation include MOI of viral vector, strength of promoter driving GFP expression, cell type transduced and incubation time after gene transfer. We also found that weak GFP signals could be interfered by background signals, whereas strong GFP signals could overshot the detection limitation of the flow cytometer and resulted in a deviation from linearity which was prevented by adjusting the setting in flow cytometer. Moreover, we compared promoter strength as measured by MFI × POI and found that the relative activity of CMV promoter to PGK promoter was 20 to 47 folds in A549 cells and 32 to > 100 folds in H1299 cells. CONCLUSIONS: The linear correlation between MFI × POI and a wide range of adenoviral MOI provides an efficient method to investigate factors regulating protein expression and to estimate virus titers.


Assuntos
Infecções por Adenoviridae/virologia , Adenoviridae/fisiologia , Fluorescência , Proteínas de Fluorescência Verde/metabolismo , Regiões Promotoras Genéticas , Linhagem Celular Tumoral , Citomegalovirus/fisiologia , Citometria de Fluxo , Vetores Genéticos/genética , Vetores Genéticos/metabolismo , Humanos , Fosfoglicerato Quinase/metabolismo
14.
J Biol Chem ; 288(46): 33462-9, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24089527

RESUMO

Caveolin-1 (Cav-1) interacts with and mediates protein trafficking and various cellular functions. Derlin-1 is a candidate for the retrotranslocation channel of endoplasmic reticulum proteins. However, little is known about how Derlin-1 mediates glycosylated protein degradation. Here, we identified Cav-1 as a key player in Derlin-1- and p97-mediated cyclooxygenase 2 (COX-2) ubiquitination and degradation. Derlin-1 augmented the interaction of Cav-1 and COX-2 and mediated the degradation of COX-2 in a COX-2 C terminus-dependent manner. Suppression of Cav-1 decreased the ubiquitination of COX-2, and mutation of Asn-594 to Ala to disrupt N-glycosylation at the C terminus of COX-2 reduced the interaction of COX-2 with Cav-1 but not Derlin-1. Moreover, suppression of p97 increased the ubiquitination of COX-2 and up-regulated COX-2 but not COX-1. Cav-1 enhanced the interaction of p97 with Ufd1 and Derlin-1 and collaborated with p97 to interact with COX-2. Cav-1 may be a cofactor in the interaction of Derlin-1 and N-glycosylated COX-2 and may facilitate Derlin-1- and p97 complex-mediated COX-2 ubiquitination, retrotranslocation, and degradation.


Assuntos
Adenosina Trifosfatases/metabolismo , Caveolina 1/metabolismo , Proteínas de Ciclo Celular/metabolismo , Ciclo-Oxigenase 2/metabolismo , Proteínas de Membrana/metabolismo , Complexos Multiproteicos/metabolismo , Proteólise , Ubiquitinação/fisiologia , Proteínas Adaptadoras de Transporte Vesicular , Adenosina Trifosfatases/genética , Animais , Caveolina 1/genética , Proteínas de Ciclo Celular/genética , Ciclo-Oxigenase 2/genética , Células HEK293 , Humanos , Peptídeos e Proteínas de Sinalização Intercelular , Peptídeos e Proteínas de Sinalização Intracelular , Proteínas de Membrana/genética , Camundongos , Complexos Multiproteicos/genética , Transporte Proteico/fisiologia , Proteínas/genética , Proteínas/metabolismo , Proteína com Valosina
15.
Comput Struct Biotechnol J ; 21: 1820-1827, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36923470

RESUMO

Polymerase chain reaction (PCR) is a powerful molecular biology assay for gene detection and quantification. Conventional DNA primers for PCR often suffer from poor sensitivity in specific gene detection. Recently, oligonucleotides containing methyl phosphotriester (MPTE-DNA) have been developed with enhanced DNA hybridization and improved gene detection sensitivity. Yet, site-specific MPTE-modifications on DNA primers have been reported to affect PCR amplification efficiencies while the detailed mechanism remains elusive. Here, we utilized molecular dynamics (MD) simulation to examine the effects of site-specific MPTE-modified primers on the structure and motions of DNA/Taq polymerase complexes. All tested MPTE-DNA/Taq complexes exhibited RMSD values below 2 Å, indicating insignificant effects of all methylation sites on the complex stability. The energetic and hydrogen-bonding analyses suggest minor effects of methylation at t-3, t-4, t-6, and t-7 positions on the DNA-Taq interaction. Principal component analyses further reveal that only t-3, and t-7 methylations preserve the motions of the Taq thumb domain. The site-specific methylation affects the interaction between DNA and the surrounding protein residues, resulting in allosteric-like effects on the DNA/Taq complex. The MD data complement the best experimentally observed PCR efficacies for the t-3 and t-7 positions among all tested MPTE-primers. The unveiled molecular insights can benefit the design of novel PCR primers for improving genetic testing platforms.

16.
Microorganisms ; 11(7)2023 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-37512973

RESUMO

Foliar diseases caused by Stemphylium and Colletotrichum species are among the major biotic factors limiting Welsh onion production in Taiwan. Owing to concerns about the environment and the development of pathogen resistance to existing fungicides, biological control using endophytes is emerging as an eco-friendly alternative to chemical control. The aim of the present study was to isolate endophytes from healthy Welsh onion leaves and investigate their antagonistic potential against the major phytopathogenic fungi associated with Welsh onion plants in Taiwan. A total of 109 bacterial and 31 fungal strains were isolated from healthy Welsh onion leaves and assigned to 16 bacterial and nine fungal genera using morphological and molecular characterization based on DNA sequence data obtained from nuclear internal transcribed spacer (nrITS) (fungi) and 16S rRNA (bacteria). Evaluation of these endophytic isolates for biocontrol activity against leaf blight pathogens Colletotrichum spaethianum strain SX15-2 and Stemphylium vesicarium strain SX20-2 by dual culture assay and greenhouse experiments resulted in the identification of two bacterial isolates (GFB08 and LFB28) and two fungal isolates (GFF06 and GFF08) as promising antagonists to leaf blight pathogens. Among the four selected isolates, Bacillus strain GFB08 exhibited the highest disease control in the greenhouse study. Therefore, Bacillus strain GFB08 was further evaluated to understand the mechanism underlying its biocontrol efficacy. A phylogenetic analysis based on six genes identified Bacillus strain GFB08 as B. velezensis. The presence of antimicrobial peptide genes (baer, bamC, bmyB, dfnA, fenD, ituC, mlna, and srfAA) and the secretion of several cell wall degrading enzymes (CWDEs), including cellulase and protease, confirmed the antifungal nature of B. velezensis strain GFB08. Leaf blight disease suppression by preventive and curative assays indicated that B. velezensis strain GFB08 has preventive efficacy on C. spaethianum strain SX15-2 and both preventive and curative efficacy on S. vesicarium strain SX20-2. Overall, the current study revealed that healthy Welsh onion leaves harbour diverse bacterial and fungal endophytes, among which the endophytic bacterial strain, B. velezensis strain GFB08, could potentially be used as a biocontrol agent to manage the leaf blight diseases of Welsh onion in Taiwan.

17.
J Microbiol Immunol Infect ; 56(6): 1139-1146, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37735047

RESUMO

BACKGROUND: A pay-for-performance plan for rapid antiretroviral therapy (ART) commencement was initiated in 2018, while a modified testing algorithm offers immunochromatographic test (ICT) to replace Western blot (WB), and simultaneous testing with ICT and Nucleic Acid Amplification Test (NAAT) for HIV-positive sera was adopted in 2019 in Taiwan. METHODS: Serum specimens collected from 1117 suspected or confirmed HIV infection cases in 2016-2019 were reassessed the performance of WB, ICT, and NAAT. We reviewed the medical records of 10,732 individuals diagnosed with HIV in 2015-2021 to determine the time from screening to confirmatory diagnosis, followed by ART commencement. RESULTS: All 860 WB-positives were also positive by ICT and NAAT. The positive detection percentages were 37.0% by ICT and 51.4% by NAAT for 257 WB-indeterminate and -negative sera. The sensitivity for WB and ICT was 93.8% and 95.5%, respectively. In the people living with HIV (PLHIV) cohort, the median time from initial positive to confirmatory diagnosis decreased from 5 to 6 days before 2019 to 1 day in 2021. The median time from initial positive to ART initiation decreased from 37 days in 2015, 14 days in 2018, to 6 days in 2021. Compared to 2015-2017, the time to ART initiation was 91.48 days lower in 2018 (P < 0.001) and 100.66 days lower in 2019-2021 (P < 0.001) by the adjusted linear regression model. CONCLUSION: A significant decrease in the time to ART initiation was observed after initiation of the pay-for-performance program and optimized testing algorithm in Taiwan.


Assuntos
Infecções por HIV , Humanos , Infecções por HIV/diagnóstico , Infecções por HIV/tratamento farmacológico , Reembolso de Incentivo , Taiwan , Teste de HIV , Algoritmos
18.
BMC Complement Med Ther ; 23(1): 79, 2023 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-36899361

RESUMO

BACKGROUND: The rich biodiversity of medicinal plants and their importance as sources of novel therapeutics and lead compounds warrant further research. Despite advances in debulking surgery and chemotherapy, the risks of recurrence of ovarian cancer and resistance to therapy are significant and the clinical outcomes of ovarian cancer remain poor or even incurable. OBJECTIVE: This study aims to investigate the effects of leaf extracts from a medicinal plant Leea indica and its selected phytoconstituents on human ovarian cancer cells and in combination with oxaliplatin and natural killer (NK) cells. METHODS: Fresh, healthy leaves of L. indica were harvested and extracted in 70% methanol by maceration. The crude extract was partitioned with n-hexane, dichloromethane and ethyl acetate. Selected extracts and compounds were analyzed for their effects on cell viability of human ovarian cancer cells, NK cell cytotoxicity, and stress ligands expression for NK cell receptors. They were also evaluated for their effects on TNF-α and IL-1ß production by enzyme-linked immunosorbent assay in lipopolysaccharide-stimulated human U937 macrophages. RESULTS: Leaf extracts of L. indica increased the susceptibility of human ovarian tumor cells to NK cell-mediated cytotoxicity. Treatment of cancer cells with methyl gallate but not gallic acid upregulated the expression of stress ligands. Tumor cells pretreated with combination of methyl gallate and low concentration of oxaliplatin displayed increased levels of stress ligands expression and concomitantly enhanced susceptibility to NK cell-mediated cytolysis. Further, NK cells completely abrogated the growth of methyl gallate-pretreated ovarian cancer cells. The leaf extracts suppressed TNF-α and IL-1ß production in human U937 macrophages. Methyl gallate was more potent than gallic acid in down-regulating these cytokine levels. CONCLUSIONS: We demonstrated for the first time that leaf extracts of L. indica and its phytoconstituent methyl gallate enhanced the susceptibility of ovarian tumor cells to NK cell cytolysis. These results suggest that the combined effect of methyl gallate, oxaliplatin and NK cells in ovarian cancer cells warrants further investigation, for example for refractory ovarian cancer. Our work is a step towards better scientific understanding of the traditional anticancer use of L. indica.


Assuntos
Neoplasias Ovarianas , Plantas Medicinais , Feminino , Humanos , Extratos Vegetais/farmacologia , Oxaliplatina/farmacologia , Fator de Necrose Tumoral alfa , Células Matadoras Naturais
19.
Polymers (Basel) ; 14(10)2022 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-35631943

RESUMO

The diffusion of small molecules or ions within polymeric materials is critical for their applications, such as polymer electrolytes. Cross-linking has been one of the common strategies to modulate solute diffusivity and a polymer's mechanical properties. However, various studies have shown different effects of cross-linking on altering the solute transports. Here, we utilized coarse-grained molecular dynamics simulation to systematically analyze the effects of cross-linking and polymer rigidity of solute diffusive behaviors. Above the glass transition temperature Tg, the solute diffusion followed the Vogel-Tammann-Fulcher (VTF) equation, D = D0 e-Ea/R(T-T0). Other than the conventional compensation relation between the activation energy Ea and the pre-exponential factor D0, we also identified a correlation between Ea and Vogel temperature T0. We further characterized an empirical relation between T0 and cross-linking density. Integrating the newly identified correlations among the VTF parameters, we formulated a relation between solute diffusion and the cross-linking density. The combined results proposed the criteria for the optimal solute diffusivity in cross-linked polymers, providing generic guidance for novel polymer electrolyte design.

20.
Sci Total Environ ; 841: 156745, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35716746

RESUMO

Solid-recovered fuels (SRFs) with low chlorine (Cl) contents are urgently needed, particularly considering the limited availability of energy resources globally. Two main sources of chlorinated pollution in municipal solid wastes, namely food waste and polyvinyl chloride (PVC), were used as raw materials for SRF production. These materials were dechlorinated using alkaline adsorbents (calcium hydroxide (Ca(OH)2) and sodium bicarbonate (NaHCO3)), yielding five sample SRFs. The SRFs had low heating values (LHVs) of 14.10-15.12 MJ/kg. The alkaline adsorbents were introduced during dry dechlorination, which increased the LHVs by 8.4 MJ/g. Approximately 50 % of the total Cl content was transformed into the liquid and gaseous phases after incineration of the SRF. The PVC content was increased to increase the amount of gaseous Cl produced. Conversely, the yields of liquid and solid Cl increased when the FW content was increased. Among alkaline adsorbents, Ca(OH)2 exhibited better adsorption performance than NaHCO3. Upon mixing ~15 wt% of Ca(OH)2 with the SRFs, the highest Cl removal efficiency (77 %) in the gaseous phase was achieved. Over 90 % of the total Cl content was converted into solid-phase calcium chloride and sodium chloride by the alkaline adsorbents. The total cost of the SRF was US$85.48/t, of which labor and electricity costs accounted for 50 % and 25 %, respectively.


Assuntos
Cloreto de Polivinila , Eliminação de Resíduos , Cloro , Alimentos , Incineração , Resíduos Sólidos/análise
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