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1.
Artículo en Inglés | MEDLINE | ID: mdl-34064690

RESUMEN

The first report of the red imported fire ant (RIFA), Solenopsis invicta Buren, in Taiwan was in the city of Taoyuan in 2003. The government has made great efforts to bring RIFA-infested areas under control. RIFA has gradually spread outward since its discovery, but it is still confined in northern Taiwan, in part due to the control efforts. RIFA is well established in densely populated environments (i.e., urban areas), causing damage to public utilities and significantly affects the inhabitants of Taiwan. Out of 10,127 human encounters with RIFA reported by the Plant Pest Information Management System in the Bureau of Animal and Plant Health Inspection and Quarantine, Council of Agriculture, Executive Yuan, 3819 (37.71%) persons were stung, with 834 (21.8%) persons exhibiting wheal-and-flare reaction (swelling and redness of the skin). Among the victims, 288 (7.5%) sought medical care, and about 21 (0.6%) developed severe cellulitis and urticaria. Unexpectedly, 2.8% (106) of the victims exhibited anaphylactic shock, which was higher than previously reported cases (1%). The high anaphylactic shock percentage was probably because most victims were elderly farmers or because Asian people have higher sensitivity to the RIFA sting. RIFA is well adapted to the environmental conditions in Taiwan, which makes it extremely difficult (if not impossible) to eradicate. The management of RIFA in the future should focus on lowering the speed of spread to mitigate possible dangers to the inhabitants. Six major challenges of RIFA management in Taiwan are also discussed.


Asunto(s)
Hormigas , Anciano , Animales , Humanos , Cambio Social , Taiwán
2.
Inorg Chem ; 60(7): 4764-4771, 2021 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-33721490

RESUMEN

The reaction of Re(CO)5Cl with 4-mercaptopyridine (4-PySH) led to the formation of [Re(CO)3(4-HPyS)3]Cl (1), showing three hydrogen-bonding donors of 4-PySH ligands as well as a characteristic ligand-to-metal charge-transfer absorption at ca. 380 nm. In this regard, a variety of anions, i.e., CN-, OAc-, F-, Cl-, Br-, I-, PF6-, NO3-, ClO4-, and H2PO4-, were examined to study anion-recognition studies through hydrogen-bonding functionalities. Upon the addition of CN- to a methanolic solution of complex 1, a remarkable spectral change with an isosbestic point at ca. 314 nm in the absorption spectra was observed, with a binding constant (Kb) calculated to be 24770 M-1. Moreover, the OAc- anion also shows a similar trend, but a mild spectral change, with Kb calculated to be 2170 M-1. Unlike those of CN- and OAc-, the addition of F-, Cl-, Br-, and I- anions causes a less pronounced spectral change with an isosbestic point at ca. 350 nm and Kb calculated to be 2863-750 M-1. However, almost no spectral change can be observed for other anions (i.e., PF6-, NO3-, H2PO4-, and ClO4-). Interestingly, the molecular loops of [Re(CO)3Cl(Py2S2)]2 (2; Py2S2 = 4,4'-dipyridyl disulfide) and [Re(CO)3Cl(Py2S)0.35(Py2S2)0.65]2 (3; Py2S = 4,4'-dipyridyl sulfide) can be isolated and structurally characterized by X-ray diffraction, where those crystals were grown from diethyl ether diffusion into a methanolic solution of complex 1 with [Bu4N]CN and [Bu4N]NO3, respectively. It is noted that such unusual ligand-coupling reactions toward the homoligand and hybrid-ligand loops of complexes 2 and 3 can be achieved at room temperature in this study.

3.
Mol Genet Genomic Med ; 8(10): e1455, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32794656

RESUMEN

BACKGROUND: Exome sequencing has recently become more readily available, and more information about incidental findings has been disclosed. However, data from East Asia are scarce. We studied the application of exome sequencing to the identification of pathogenic/likely pathogenic variants in the ACMG 59 gene list and the frequency of these variants in the Taiwanese population. METHODS: This study screened 161 Taiwanese exomes for variants from the ACMG 59 gene list. The identified variants were reviewed based on information from different databases and the available literature and classified according to the ACMG standard guidelines. RESULTS: We identified seven pathogenic/likely pathogenic variants in eight individuals, with five participants with autosomal recessive variants in one allele and three participants with autosomal dominant variants. Approximately 1.86% (3/161) of the Taiwanese individuals had a reportable pathogenic/likely pathogenic variant as determined by whole-exome sequencing (WES), which was comparable to the proportions published previously in other countries. We further investigated the high carrier rate of rare variants in the ATP7B gene, which might indicate a founder effect in our population. CONCLUSION: This study was the first to provide Taiwanese population data of incidental findings and emphasized a high carrier rate of candidate pathogenic/likely pathogenic variants in the ATP7B gene.


Asunto(s)
Secuenciación del Exoma/estadística & datos numéricos , Frecuencia de los Genes , Población/genética , ATPasas Transportadoras de Cobre/genética , Humanos , Mutación , Taiwán
4.
J Agric Food Chem ; 62(25): 5932-8, 2014 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-24932548

RESUMEN

Carnosine (CAR) is an endogenous peptide and present in lens, but there is little evidence for its effectiveness in calpain-induced proteolysis inhibition and its differential effects toward different wavelengths of ultraviolet (UV) irradiation. This study aimed to develop three in vitro cataract models to compare the mechanisms underlying the protective activities of CAR. Crude crystallins extracted from porcine lenses were used for antiproteolysis assays, and purified γ-crystallins were used for anti-UV assays. The turbidity in those in vitro models mimics cataract formation and was assayed by measuring optical density (OD) at 405 nm. The effectiveness of CAR on calpain-induced proteolysis was studied at 37 and 58 °C. Patterns of proteins were then analyzed by SDS-PAGE. The turbidity was reduced significantly (p<0.05) at 60 min measurements with the increased concentration of CAR (10-300 mM). SDS-PAGE showed that the decreased intensities at both ∼28 and ∼30 kDa protein bands in heat-enhanced assays were ameliorated by CAR at ≥10 mM concentrations. In UV-B studies, CAR (200, 300 mM) reduced the turbidity of γ-crystallin significantly (p<0.05) at 6 h observations. The turbidity of samples containing γ-crystallins was ameliorated while incubated with CAR (100, 300 mM) significantly (p<0.05) following 4 h of exposure to UV-C. SDS-PAGE showed that the presence of CAR reduced UV-B-induced aggregation of γ-crystallins at ∼44 kDa and resulted in less loss of γ-crystallin following UV-C exposure. The result of modeling also suggests that CAR acts as an inhibitor of calpain. In conclusion, CAR protects lens proteins more readily by inhibiting proteolysis and UV-C-induced degradation than aggregation induced by UV-B irradiation.


Asunto(s)
Calpaína/metabolismo , Carnosina/metabolismo , Catarata/metabolismo , Glicoproteínas/metabolismo , Cristalino/metabolismo , Secuencia de Aminoácidos , Animales , Calpaína/química , Calpaína/genética , Cristalinas/metabolismo , Humanos , Datos de Secuencia Molecular , Proteolisis/efectos de la radiación , Alineación de Secuencia , Porcinos , Rayos Ultravioleta/efectos adversos
5.
Mol Vis ; 17: 1862-70, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21850160

RESUMEN

PURPOSE: In this study, we investigated the biochemical pharmacology of pirenoxine (PRX) and catalin under in vitro selenite/calcium- and ultraviolet (UV)-induced lens protein turbidity challenges. The systemic effects of catalin were determined using a selenite-induced cataractogenesis rat model. METHODS: In vitro cataractogenesis assay systems (including UVB/C photo-oxidation of lens crystallins, calpain-induced proteolysis, and selenite/calcium-induced turbidity of lens crystallin solutions) were used to screen the activity of PRX and catalin eye drop solutions. Turbidity was identified as the optical density measured using spectroscopy at 405 nm. We also determined the in vivo effects of catalin on cataract severity in a selenite-induced cataract rat model. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) was applied to analyze the integrity of crystallin samples. RESULTS: PRX at 1,000 µM significantly delayed UVC-induced turbidity formation compared to controls after 4 h of UVC exposure (p<0.05), but not in groups incubated with PRX concentrations of <1,000 µM. Results were further confirmed by SDS-PAGE. The absolute γ-crystallin turbidity induced by 4 h of UVC exposure was ameliorated in the presence of catalin equivalent to 1~100 µM PRX in a concentration-dependent manner. Samples with catalin-formulated vehicle only (CataV) and those containing PRX equivalent to 100 µM had a similar protective effect after 4 h of UVC exposure compared to the controls (p<0.05). PRX at 0.03, 0.1, and 0.3 µM significantly delayed 10 mM selenite- and calcium-induced turbidity formation compared to controls on days 0~4 (p<0.05). Catalin (equivalent to 32, 80, and 100 µM PRX) had an initial protective effect against selenite-induced lens protein turbidity on day 1 (p<0.05). Subcutaneous pretreatment with catalin (5 mg/kg) also statistically decreased the mean cataract scores in selenite-induced cataract rats on post-induction day 3 compared to the controls (1.3±0.2 versus 2.4±0.4; p<0.05). However, catalin (equivalent to up to 100 µM PRX) did not inhibit calpain-induced proteolysis activated by calcium, and neither did 100 µM PRX. CONCLUSIONS: PRX at micromolar levels ameliorated selenite- and calcium-induced lens protein turbidity but required millimolar levels to protect against UVC irradiation. The observed inhibition of UVC-induced turbidity of lens crystallins by catalin at micromolar concentrations may have been a result of the catalin-formulated vehicle. Transient protection by catalin against selenite-induced turbidity of crystallin solutions in vitro was supported by the ameliorated cataract scores in the early stage of cataractogenesis in vivo by subcutaneously administered catalin. PRX could not inhibit calpain-induced proteolysis activated by calcium or catalin itself, and may be detrimental to crystallins under UVB exposure. Further studies on formulation modifications of catalin and recommended doses of PRX to optimize clinical efficacy by cataract type are warranted.


Asunto(s)
Catarata/tratamiento farmacológico , Cristalino/efectos de los fármacos , Soluciones Oftálmicas/uso terapéutico , Oxazinas/uso terapéutico , gamma-Cristalinas/metabolismo , Animales , Animales Recién Nacidos , Calcio/metabolismo , Calcio/farmacología , Calpaína/efectos adversos , Calpaína/farmacología , Catarata/inducido químicamente , Catarata/metabolismo , Catarata/prevención & control , Relación Dosis-Respuesta a Droga , Cálculo de Dosificación de Drogas , Electroforesis en Gel de Poliacrilamida , Cristalino/metabolismo , Cristalino/patología , Soluciones Oftálmicas/administración & dosificación , Oxazinas/administración & dosificación , Proteolisis/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Selenito de Sodio/administración & dosificación , Selenito de Sodio/efectos adversos , Análisis Espectral , Porcinos , Rayos Ultravioleta , gamma-Cristalinas/química
6.
Inorg Chem ; 50(1): 365-77, 2011 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-21138325

RESUMEN

This study investigated whether and how pirenoxine (PRX) interacts with selenite or calcium ions, as these two ions have been proven respectively a factor leading to the formation of lens cataract. UV, NMR, and isothermal titration calorimetry (ITC) analysis indicated that PRX could bind maximum up to six selenite anions and the binding site preference was concentration dependent with the peripheral binding first followed by the π-π interactions with the aromatic moiety; while for calcium cation interaction the 3-carboxylate and ß-ketoimine functional groups were responsible for chelating calcium ions. The results obtained by MP2/6-31+G(d) molecular orbital calculations provided theoretical evidence in support of the π-π interactions between selenite and the PRX aromatic framework, and further analysis of the binding energies with the aromatic moiety indicates that these interactions take place most likely at the benzoquinone (ring I) π-system. The calcium binding preferences with PRX were also determined based on the stabilization energy obtained by B3LYP/6-31+G(d) calculations, showing the binding preferences were site 2 > site 1 > site 3 > ring II, consistent with the experimental data. The in vitro study of the reduction of selenite or calcium ions-induced lens turbidity by PRX with ditopic recognition properties was thus demonstrated. These results may provide a rationale for using PRX as an anti-cataract agent and warrant further biological studies.


Asunto(s)
Calcio , Complejos de Coordinación/metabolismo , Oxazinas/metabolismo , Selenito de Sodio , Calcio/efectos adversos , Calcio/metabolismo , Catarata/inducido químicamente , Catarata/tratamiento farmacológico , Catarata/metabolismo , Complejos de Coordinación/química , Complejos de Coordinación/uso terapéutico , Humanos , Cristalino/efectos de los fármacos , Cristalino/metabolismo , Cristalino/patología , Espectroscopía de Resonancia Magnética , Conformación Molecular , Nefelometría y Turbidimetría , Oxazinas/química , Oxazinas/uso terapéutico , Selenito de Sodio/efectos adversos , Selenito de Sodio/metabolismo , Termodinámica
7.
Cancer Res ; 69(18): 7347-56, 2009 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-19738071

RESUMEN

Lenalidomide and pomalidomide have both been evaluated clinically for their properties as anticancer agents, with lenalidomide being available commercially. We previously reported that both compounds cause cell cycle arrest in Burkitt's lymphoma and multiple myeloma cell lines by increasing the level of p21(WAF-1) expression. In the present study, we unravel the molecular mechanism responsible for p21(WAF-1) up-regulation using Namalwa cells as a human lymphoma model. We show that the increase of p21(WAF-1) expression is regulated at the transcriptional level through a mechanism independent of p53. Using a combination of approaches, we show that several GC-rich binding transcription factors are involved in pomalidomide-mediated up-regulation of p21(WAF-1). Furthermore, we report that p21(WAF-1) up-regulation is associated with a switch from methylated to acetylated histone H3 on p21(WAF-1) promoter. Interestingly, lysine-specific demethylase-1 (LSD1) silencing reduced both pomalidomide and lenalidomide up-regulation of p21(WAF-1), suggesting that this histone demethylase is involved in the priming of the p21(WAF-1) promoter. Based on our findings, we propose a model in which pomalidomide and lenalidomide modify the chromatin structure of the p21(WAF-1) promoter through demethylation and acetylation of H3K9. This effect, mediated via LSD1, provides GC-rich binding transcription factors better access to DNA, followed by recruitment of RNA polymerase II and transcription activation. Taken together, our results provide new insights on the mechanism of action of pomalidomide and lenalidomide in the regulation of gene transcription, imply possible efficacy in p53 mutated and deleted cancer, and suggest new potential clinical uses as an epigenetic therapy.


Asunto(s)
Inhibidor p21 de las Quinasas Dependientes de la Ciclina/biosíntesis , Linfoma/tratamiento farmacológico , Mieloma Múltiple/tratamiento farmacológico , Oxidorreductasas N-Desmetilantes/metabolismo , Talidomida/análogos & derivados , Antineoplásicos/farmacología , Línea Celular Tumoral , Cromatina/metabolismo , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Histona Demetilasas , Histonas/genética , Histonas/metabolismo , Humanos , Lenalidomida , Linfoma/genética , Linfoma/metabolismo , Mieloma Múltiple/genética , Mieloma Múltiple/metabolismo , Oxidorreductasas N-Desmetilantes/genética , Talidomida/farmacología , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
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