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1.
Artículo en Inglés | MEDLINE | ID: mdl-38517769

RESUMEN

BACKGROUND: With lifestyle changes, the prevalence of flatfoot is increasing year by year, with a prevalence of 29%. Flatfoot will lead to an inevitable injury and reduce the quality of life. Short foot exercises can enhance the strength of the intrinsic muscles of the foot and improve the symptoms of flatfoot. However, there is controversy regarding its specific efficacy. OBJECTIVE: This meta-analysis quantitatively evaluates the effect of short foot training on patients with flatfeet and provides evidence to inform the clinical approach to short foot training in patients with flat feet. METHODS: A total of eight databases were searched, including CNKI, WANFANG, VIP, and CBM in Chinese and PubMed, Cochrane, Web of Science, and Embase in English. The timeframe for searching the literature was March 2023 for each database build. English database search terms and search formulas were: (flat foot OR talipes valgus OR talipes calcaneovalgus) AND (short foot exercises OR physical therapy OR neurophysiotherapy). RESULTS: The current pooled results show no significant difference in the improvement of the navicular drop test and foot posture index with short foot exercises compared to controls; only short foot exercises greater than 6 w showed a significant improvement in the navicular drop test, and sensitivity analysis showed a significant improvement in the foot posture index with short foot exercises. CONCLUSION: This systematic review and meta-analysis showed that short foot exercises need a larger sample size to find their effect on improving flat feet; the duration of the intervention is a factor. As most studies are currently unclear whether the participants were patients with flat feet or asymptomatic individuals with flat feet the disease syndrome in patients with flatfoot may also be a factor.

2.
JACS Au ; 4(2): 666-679, 2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-38425920

RESUMEN

Reactant-induced structural evolutions of heterogeneous metal catalysts are frequently observed in numerous catalytic systems, which can be associated with the formation or deactivation of active sites. In this work, we will show the structural transformation of subnanometer Pt clusters in pure-silica MFI zeolite structure in the presence of CO, O2, and/or H2O and the catalytic consequences of the Pt-zeolite materials derived from various treatment conditions. By applying the appropriate pretreatment under a reactant atmosphere, we can precisely modulate the size distribution of Pt species spanning from single Pt atoms to small Pt nanoparticles (1-5 nm) in the zeolite matrix, resulting in the desirably active and stable Pt species for CO oxidation. We also show the incorporation of Fe into the zeolite framework greatly promotes the stability of Pt species against undesired sintering under harsh conditions (up to 650 °C in the presence of CO, O2, and moisture).

3.
Cell Mol Immunol ; 21(2): 119-133, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38238440

RESUMEN

The COVID-19 pandemic, which was caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has become a worldwide health crisis due to its transmissibility. SARS-CoV-2 infection results in severe respiratory illness and can lead to significant complications in affected individuals. These complications encompass symptoms such as coughing, respiratory distress, fever, infectious shock, acute respiratory distress syndrome (ARDS), and even multiple-organ failure. Animal models serve as crucial tools for investigating pathogenic mechanisms, immune responses, immune escape mechanisms, antiviral drug development, and vaccines against SARS-CoV-2. Currently, various animal models for SARS-CoV-2 infection, such as nonhuman primates (NHPs), ferrets, hamsters, and many different mouse models, have been developed. Each model possesses distinctive features and applications. In this review, we elucidate the immune response elicited by SARS-CoV-2 infection in patients and provide an overview of the characteristics of various animal models mainly used for SARS-CoV-2 infection, as well as the corresponding immune responses and applications of these models. A comparative analysis of transcriptomic alterations in the lungs from different animal models revealed that the K18-hACE2 and mouse-adapted virus mouse models exhibited the highest similarity with the deceased COVID-19 patients. Finally, we highlighted the current gaps in related research between animal model studies and clinical investigations, underscoring lingering scientific questions that demand further clarification.


Asunto(s)
COVID-19 , SARS-CoV-2 , Ratones , Cricetinae , Humanos , Animales , Pandemias , Vacunas contra la COVID-19 , Hurones , Modelos Animales de Enfermedad
4.
Dysphagia ; 2023 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-38117313

RESUMEN

Stroke is the leading cause of death and disability among adults. The incidence of stroke per 100, 000 patient-years was 2875. As many as 37% to 78% of patients with acute strokes suffer dysphagia. Dysphagia can easily lead to inhalation pneumonia, dehydration, malnutrition, and other serious complications, affecting the quality of life of stroke patients and increasing their mortality. Effective prevention and treatment of post-stroke dysphagia are of great significance to improving the prognosis and quality of life of patients. Some studies have shown that Pharyngeal cavity electrical stimulation-assisted swallowing (PCES-assisted swallowing) has a positive effect on patients with post-stroke dysphagia. This study will evaluate the effects of PCES-assisted swallowing on post-stroke dysphagia, including swallowing function, withdrawal rate of nasal feeding tubes, duration of hospitalization, and so on. Randomized controlled trials (RCTs) of PCES-assisted swallowing in the treatment of post-stroke dysphagia were searched in eight databases, including Cochrane Library, Embase, PubMed, Web of Science, Chinese Biomedical Literature Database, VIP Information Resource System, CNKI, and Wanfang Medical Science. The retrieval time was from the database establishment to June 2022. Rayyan was used to screen the retrieved literature risk of bias for included studies and was calculated using ROB2.0. The RevMan 5.3 software was used for the meta-analysis with the standard mean difference (SMD) and 95% confidence interval (CI). The model type was a random effect model, The risk ratio (RR) was used as the effect size for the two categorical variables. The swallowing function scores, withdrawal rate of nasal feeding tubes, and Length of stay (LOS) of the intervention and control groups were extracted, and the results of the meta-analysis were presented using a forest plot. Six studies from 2010 to 2018 with a total of 341 people were included in the meta-analysis. All studies reported quantitative outcome measures for the severity of dysphagia, and some reported the withdrawal rate of nasal feeding tubes, LOS, and penetration-aspiration-scale (PAS). The overall swallowing function of the PCES group was better than that of the control group (SMD = - 0.20, 95%CI - 0.38 to - 0.03, P = 0.02). In terms of the severity of dysphagia, there was a statistically significant difference in the Dysphagia Severity Rating scale (DSRS) between the Pharyngeal cavity electrical stimulation (PCES) group and the control group (SMD = - 0.24, 95%CI - 0.48 to 0, P = 0.05). The PCES group nasal feeding withdrawal rate of nasal feeding tubes was higher than the control group (RR = 2.88, 95% CI 1.15 to 7.26, P = 0.02). There was no significant difference in the LOS between the PCES group and the control group (SMD = - 0.19, 95%CI - 0.44 to 0.07, P = 0.15). This systematic review and meta-analysis provide reasonably reliable evidence that PCES-assisted swallowing can improve nasogastric feeding swallowing function and the withdrawal rate of nasal feeding tubes in patients with post-stroke dysphagia. However, the evidence for reducing oral feeding, aspiration, and length of hospitalization stay is lacking, and further studies are needed.

5.
World J Psychiatry ; 13(9): 607-619, 2023 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-37771645

RESUMEN

Deep transcranial magnetic stimulation (DTMS) is a new non-invasive neuromodulation technique based on repetitive transcranial magnetic stimulation tech-nology. The new H-coil has significant advantages in the treatment and mechanism research of psychiatric and neurological disorders. This is due to its deep stimulation site and wide range of action. This paper reviews the clinical progress of DTMS in psychiatric and neurological disorders such as Parkinson's disease, Alzheimer's disease, post-stroke motor dysfunction, aphasia, and other neurological disorders, as well as anxiety, depression, and schizophrenia.

6.
Signal Transduct Target Ther ; 8(1): 123, 2023 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-36922500

RESUMEN

Persistent asymptomatic (PA) SARS-CoV-2 infections have been identified. The immune responses in these patients are unclear, and the development of effective treatments for these patients is needed. Here, we report a cohort of 23 PA cases carrying viral RNA for up to 191 days. PA cases displayed low levels of inflammatory and interferon response, weak antibody response, diminished circulating follicular helper T cells (cTfh), and inadequate specific CD4+ and CD8+ T-cell responses during infection, which is distinct from symptomatic infections and resembling impaired immune activation. Administration of a single dose of Ad5-nCoV vaccine to 10 of these PA cases elicited rapid and robust antibody responses as well as coordinated B-cell and cTfh responses, resulting in successful viral clearance. Vaccine-induced antibodies were able to neutralize various variants of concern and persisted for over 6 months, indicating long-term protection. Therefore, our study provides an insight into the immune status of PA infections and highlights vaccination as a potential treatment for prolonged SARS-CoV-2 infections.


Asunto(s)
COVID-19 , Humanos , SARS-CoV-2 , Infecciones Asintomáticas , Anticuerpos Antivirales
7.
Front Psychiatry ; 13: 892453, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36238941

RESUMEN

Background: Sleep efficiency of <80% based on actigraphy was defined as insomnia as self-reported difficulty falling asleep or waking up at night three to four times per week. It is known that adequate sleep is very important for human wellbeing, affecting people's work and life, insomnia will seriously damage our daily life. There is no recognized non-drug treatment. Studies have found that Taijiquan has a positive effect on insomnia patients. This systematic review and meta-analysis will evaluate the effect of Taijiquan on insomnia. Methods: To find all randomized controlled trials exploring the effects of Taijiquan on insomnia patients in Chinese and English, eight databases (Pubmed, Embase, Cochrane library, Web of Science, CNKI, CBM, VIP, and Wanfang Data) were searched. The retrieval time is from database construction to October 2021. Searches were conducted in both English and Chinese language. A meta-analysis by mean difference (MD) and 95% confidence interval (CI) was performed with RevMan 5.3. The risk of bias for each study was accounted for according to the Cochrane Handbook. Our primary outcome was Pittsburg Sleep Quality Index. We explored sources of heterogeneity by comparing effect sizes across different types of etiology, country, control group, and intervention type. The protocol was pre-registered with PROSPERO, CRD42021284511. Results: Twenty-one RCTs published between 2004 and 2021 with 2,022 participants were included in this study. Twenty-one randomized controlled studies showed that Tai Chi significantly improved PSQI scores in patients with cancer, muscle fibrosis, and sub-health insomnia [MD = -1.16, 95% CI (-1.62, -0.71), P < 0.01]; There is insufficient evidence of improvement in patients with cerebrovascular disease [MD = -0.54, 95% CI (-1.58, 0.51), P = 0.31]; 8-form, 10-form or 24-form Yang's Taijiquan had the same effect in improving PSQI [MD = -1.33, 95% CI (-1.85, -0.81), P < 0.01]. When there is no treatment, exercise, exercise and health education as the control, taijiquan has a significant effect on insomnia treatment, and there is no difference in efficacy compared with cognitive behavioral therapy and health education (usual care) alone. Conclusions: The results of the study showed that Taijiquan significantly improved sleep quality in healthy adults and patients with chronic diseases, which suggests that Taijiquan may be considered as an alternative behavioral therapy in the treatment of insomnia. In the future, more high-quality, well-controlled randomized trials are needed to better inform clinical decisions.

8.
J Cancer ; 12(1): 99-110, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33391406

RESUMEN

GINS complex subunit 2 (GINS2) controls DNA replication. GINS2 expression is upregulated in several kinds of aggressive tumors. However, the effect of GINS2 in lung cancer remains unclear. We performed TCGA database analysis to confirm the clinical significance of GINS2 in lung cancer. After silencing GINS2 in A549 cells, we performed MTT assays, flow cytometry assays, colony formation assays, cell cycle analyses and RNA sequence analysis to elucidate the effect of GINS2 on lung cancer. Moreover, we assessed tumor growth and analyzed body fluorescence in mice as a measure of tumor burden. The TCGA database analysis demonstrated that GINS2 mRNA and protein was highly expressed in three kinds of lung cancer tissues. Subsequently, knockdown of GINS2 inhibited cell proliferation, colony formation, cell cycle arrest and apoptosis in A549 cells. On the other hand, we also investigated the effect of GINS2 on tumor formation in vivo. The analysis of nude mouse tumors showed that the tumor volume and weight of shGINS2 mice were significantly smaller than those of the control mice. To reveal the mechanism of GINS2 in lung cancer, we collected A549 cells with GINS2 knockdown to examine the downstream gene expression changes. The results showed that STAT1 and STAT2 mRNA and protein expression were significantly upregulated after GINS2 knockdown in A549 cells. Our results suggest that GINS2 inhibits the proliferation of lung cancer cells by inhibiting the STAT signaling pathway, which may be a potential biomarker for the diagnosis or prognosis of lung cancer.

9.
ChemSusChem ; 13(19): 5199-5212, 2020 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-32748524

RESUMEN

The lignin-first strategy has emerged as one of the most powerful approaches for generating novel platform chemicals from lignin by efficient depolymerization of native lignin. Because of the emergence of this novel depolymerization method and the definition of viable platform chemicals, future focus will soon shift towards innovative downstream processing strategies. Very recently, many interesting approaches have emerged that describe the production of valuable products across the whole value chain, including bulk and fine chemical building blocks, and several concrete examples have been developed for the production of polymers, pharmaceutically relevant compounds, or fuels. This Minireview provides an overview of these recent advances. After a short summary of catalytic systems for obtaining aromatic monomers, a comprehensive discussion on their separation and applications is given. This Minireview will fill the gap in biorefinery between deriving high yields of lignin monomers and tapping into their potential for making valuable consumer products.

10.
J Clin Neurosci ; 73: 245-251, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32067828

RESUMEN

Fragile X syndrome (FXS) is a common mental retardation syndrome. Anxiety and abnormal social behaviors are prominent features of FXS in humans. To better understand the effects of hyperbaric oxygen therapy (HBOT) on these behaviors, we analyzed anxiety-related and social behaviors in Fmr1 knockout mice treated by HBOT. In the open field test, HBOT group mice preferred the periphery to central areas and tended to run or walk along the wall. The results suggested that thigmotaxis was significantly increased in the HBOT group compared with the control group. In the elevated plus maze test, the percentage of distance traveled was significantly increased in the open arm and significantly decreased in the closed arm for HBOT group mice compared with control group mice. These results suggested that HBOT group mice displayed enhanced motor activity in the open arm and exhibited fewer anxiety-related behaviors. In the three-chambered social approach test, the HBOT group mice made more approaches to the wire cup containing an acquaintance mouse than control group mice in the sociability test and made more approaches to the wire cup containing a stranger mouse than control group mice in the social novelty preference test. The results suggested that HBOT group mice showed increased levels of social interaction and decreased "social anxiety" than the control group to partner mice in this test. Our findings indicated that HBOT resulted in altered anxiety and social behavior in Fmr1 knockout mice and could possibly be used as a treatment for FXS.


Asunto(s)
Síndrome del Cromosoma X Frágil/terapia , Oxigenoterapia Hiperbárica/métodos , Conducta Social , Animales , Ansiedad/terapia , Conducta Animal , Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/genética , Síndrome del Cromosoma X Frágil/genética , Masculino , Aprendizaje por Laberinto , Ratones , Ratones Endogámicos C57BL
11.
Chem Sci ; 10(38): 8768-8773, 2019 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-31803449

RESUMEN

Molecular motors that operate with high efficiency using visible light are attractive for numerous applications. Here the synthesis and characterisation of three novel visible light switchable 2nd generation molecular motors is presented. Two of them are based on push-pull systems with the third one possessing an extended π-system. With a maximum effective excitation wavelength of 530 nm we designed the most red-shifted artificial rotary motor known to date. All three motors benefit from efficient switching to the metastable isomer, high quantum yields and excellent photostability setting them apart from visible light switchable motors reported previously. The activation barriers of the rate-determining thermal helix inversion could be accurately predicted using DFT calculations and differences between the motors can be explained by distinct transition state structures. Enantiomers of push-pull motors were successfully separated and their helical twisting power in E7 liquid crystals was determined.

12.
Sci Rep ; 8(1): 8007, 2018 05 22.
Artículo en Inglés | MEDLINE | ID: mdl-29789623

RESUMEN

In previous studies, miR-29s showed tumor suppressor properties against lung cancer, which improved the survival of patients upon the administration of chemotherapy via an unknown mechanism. Here, we investigated the regulatory effects of miR-29s on the cisplatin resistance of NSCLC cells. The expression of miR-29s was assessed in 130 clinical patients and in cisplatin-treated NSCLS cell lines. MiR-29c expression was decreased in 77% of NSCLC patients. Cisplatin treatment increased the expression of miR-29c and decreased the expression of its oncogenic target AKT2 in NSCLC cell lines. A Kaplan-Meier survival analysis indicated that higher miR-29c levels led to a longer disease-free survival. In particular, patients who experienced cancer recurrences after cisplatin chemotherapy exhibited a lower level of miR-29c expression, suggesting that miR-29c activation may contribute to the chemotherapeutic efficiency of cisplatin. The enforced expression of miR-29c enhanced the cisplatin sensitivity of NSCLC cells, while the knocking down of miR-29c led to cisplatin resistance. MiR-29c amplified the therapeutic effects of cisplatin in vivo. Rescue experiments suggested that miR-29c regulates the cisplatin resistance of NSCLS cells by negatively regulating the PI3K/Akt pathway. Overall, our results demonstrated that miR-29c enhances the sensitivity of NSCLC cells to cisplatin by targeting the PI3K/Akt pathway.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Cisplatino/uso terapéutico , Resistencia a Antineoplásicos/genética , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , MicroARNs/fisiología , Células A549 , Adulto , Animales , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/patología , Estudios de Casos y Controles , Regulación hacia Abajo/genética , Femenino , Regulación Neoplásica de la Expresión Génica , Genes Supresores de Tumor/fisiología , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Masculino , Ratones , Ratones Desnudos , Fosfatidilinositol 3-Quinasas/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal/genética , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto
13.
Nat Chem ; 9(3): 250-256, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28221361

RESUMEN

Helicity switching in biological and artificial systems is a fundamental process that allows for the dynamic control of structures and their functions. In contrast to chemical approaches to responsive behaviour in helicates, the use of light as an external stimulus offers unique opportunities to invert the chirality of helical structures in a non-invasive manner with high spatiotemporal precision. Here, we report that unidirectional rotary motors with connecting oligobipyridyl ligands, which can dynamically change their chirality upon irradiation, assemble into metal helicates that are responsive to light. The motor function controls the self-assembly process as well as the helical chirality, allowing switching between oligomers and double-stranded helicates with distinct handedness. The unidirectionality of the light-induced motion governs the sequence of programmable steps, enabling the highly regulated self-assembly of fully responsive helical structures. This discovery paves the way for the future development of new chirality-dependent photoresponsive systems including smart materials, enantioselective catalysts and light-driven molecular machines.

14.
Angew Chem Int Ed Engl ; 56(1): 291-296, 2017 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-27966814

RESUMEN

Switching systems operating in a cooperative manner capable of converting light energy into mechanical motion are of great interest for optical devices, data storage, nanoscale energy converters and molecular sensing. Herein, photoswitchable monolayers were formed at the air-water interface from either a pure bis(thiaxanthylidene)-based photoswitchable amphiphile or from a mixture of the photoswitchable amphiphile with a conventional lipid dipalmitoylphosphatidylcholine (DPPC). Efficient photoisomerization of the anti-folded to syn-folded geometry of the amphiphile's central core induces changes in the surface pressure in either direction, depending on the initial molecular density. Additionally, the switching behavior can be regulated in the presence of DPPC, which influences the packing of the molecules, thereby controlling the transformation upon irradiation. Bis(thiaxanthylidene)-based photoswitchable monolayers provide a promising system to explore cooperativity and amplification of motion.

15.
Asian Pac J Cancer Prev ; 16(14): 6011-7, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26320489

RESUMEN

PURPOSE: To investigate the efficacy and safety of selective radiotherapy after distant metastasis of nasopharyngeal carcinoma (NPC) treated with dose-dense cisplatin plus fluorouracil. MATERIALS AND METHODS: Eligible patients were randomly assigned to a study group treated with dose-dense cisplatin plus fluorouracil following selective radiotherapy and a control group receiving traditional cisplatin plus fluorouracil following selective radiotherapy according to a 1:1 distribution using a digital random table method. The primary endpoint was overall survival (OS). Secondary endpoints were progression-free survival (PFS), objective response rate, relapse or progression rate in the radiation field and treatment toxicity. RESULTS: Of 52 patients in the study group, 20 cases underwent radiotherapy., while in the control group of 51 patients, 16 underwent radiotherapy. The median PFS, median OS, survival rates in 1, 2 and 3 years in study and control group were 20.9 vs 12.7months, 28.3 vs 18.8months, 85.2%vs 65.9%, 62.2% vs 18.3%, and 36.6%vs 5.2% (p values of 0.00, 0.00, 0.04, 0.00 and 0.00, respectively). Subgroup analysis showed that the median OS and survival rates of 1, 2, 3 years for patients undergoing radiotherapy in the study group better than that in control group( 43.2vs24.1 months, 94.1% vs 86.7%, 82.4% vs 43.3%, 64.7% vs 17.3%, (p=0.00, 0.57, 0.04 and 0.01, respectively). The complete response rate, objective response rate after chemotherapy and three months after radiotherapy, relapse or progression rate in radiation field in study group and in control group were 19.2% vs 3.9%, 86.5% vs 56.9%, 85% vs 50%, 95% vs 81.3% and 41.3% vs 66.7% (p =0.03, 0.00, 0.03,0.30, 0.01 respectively). The grade 3-4 acute adverse reactions in the study group were significantly higher than in the control group (53.8% vs 9.8%, p=0.00). CONCLUSIONS: The survival of patients benefits from selective radiotherapy after distant metastasis of NPC treated with dose-dense cisplatin plus fluorouracil.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Óseas/terapia , Quimioradioterapia , Neoplasias Hepáticas/terapia , Neoplasias Pulmonares/terapia , Neoplasias Nasofaríngeas/tratamiento farmacológico , Adolescente , Adulto , Anciano , Neoplasias Óseas/mortalidad , Neoplasias Óseas/secundario , Carcinoma , Estudios de Casos y Controles , Cisplatino/administración & dosificación , Femenino , Fluorouracilo/administración & dosificación , Estudios de Seguimiento , Humanos , Neoplasias Hepáticas/mortalidad , Neoplasias Hepáticas/secundario , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/secundario , Metástasis Linfática , Masculino , Persona de Mediana Edad , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/mortalidad , Neoplasias Nasofaríngeas/patología , Estadificación de Neoplasias , Pronóstico , Tasa de Supervivencia , Adulto Joven
16.
Chem Asian J ; 9(11): 3215-20, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25195657

RESUMEN

The synthesis and photophysics of two novel 2-(2'-hydroxyphenyl)benzothiazole (HBT) derivatives are presented. The electron-withdrawing trifluoromethyl (CF3) group in compound 1 facilitates the deprotonation of the phenolic hydroxy group. Well-resolved triple fluorescence from the enol, keto, and phenolic anion, which ranges from 350 to 600 nm, was detected for 1 in ethanol, which marks the first time triple fluorescence from an excited-state intramolecular proton transfer (ESIPT) molecule has been reported. Both triphenylamine and CF3 were introduced into derivative 2. Intramolecular charge transfer and the "red-edge effect" resulted in the bathochromic shift of dual fluorescence of 2. Triple fluorescence was also observed for 2 in ethanol. In mixed acetonitrile and ethanol, pure white-light emission with CIE coordinates of (0.33, 0.33) and a quantum yield of 0.25 was achieved for 2. This work provides a new avenue for the rational design of an ESIPT molecule to achieve white-light generation under mild conditions.

17.
Dis Aquat Organ ; 86(2): 93-106, 2009 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-19902838

RESUMEN

Presumptive systemic streptococcal infections were detected histologically in farmed Litopenaeus vannamei juveniles submitted from a Latin American country and the bacteria isolated. Characterization work demonstrated that the Gram-positive cocci form chains, grow aerobically and anaerobically, are oxidase- and catalase-negative, non-hemolytic, non-motile, Lancefield Group B positive and PCR positive when amplified with a universal streptococcal primer set. Differing Streptococcus identifications were obtained using API 20 Strep and Biolog systems, the former identifying the isolate as S. uberis and the latter as S. parauberis. Injection of specific pathogen-free (SPF) L. vannamei with the bacteria resulted in 100% mortality by 3 d post-injection with successful recovery of the agent from moribund test shrimp hemolymph samples. The recovered isolate was used in per os and waterborne exposure studies of SPF L. vannamei with mortalities ranging from 40 to 100% and 80 to 100%, respectively. Histologic analysis of 5 to 8 moribund shrimp from each exposure method demonstrated that all contained a severe bacteremia characterized by numerous free cocci within the hemolymph and aggregates of vacuolated hemocytes with notable intravacuolar cocci. This unique lesion type was most pronounced within the lymphoid organ and considered pathodiagnostic for this disease. Experimentally induced lesions were identical to those in naturally infected farmed shrimp and the Streptococcus sp. responsible was re-isolated, fulfilling Koch's postulates. Five freeze/thaw cycles of 10 experimentally infected shrimp were performed over a 2 mo period and the bacteria successfully cultured from all shrimp at each interval. These collective findings describe the first reported case of streptococcosis in marine penaeid shrimp in the Western Hemisphere and indicate that the agent may be disseminated via live or frozen infected shrimp.


Asunto(s)
Acuicultura , Penaeidae/microbiología , Streptococcus/fisiología , Animales , Frío , Recuento de Colonia Microbiana , Agua de Mar/microbiología , Streptococcus/aislamiento & purificación , Streptococcus/patogenicidad , Análisis de Supervivencia , Factores de Tiempo
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