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1.
Org Lett ; 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38975858

RESUMEN

Here, we report an intermolecular radical addition-based reaction sequence that permits preparation of functionalized imidazoles via a 5-step/3-pot procedure. In contrast to traditional, transition-metal mediated protocols, which generally provide access to 2-substituted imidazoles, the strategy described here allows incorporation of a structurally diverse range of complex alkyl side chains at the 4-position. This work demonstrates that intermolecular free-radical addition reactions are a powerful alternative to traditional methods used to synthesize medicinally important heterocyclic frameworks.

2.
Front Oncol ; 14: 1426558, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38974239

RESUMEN

As the projected incidence and mortality of cancer in Sub-Saharan Africa (SSA) rises to epidemic proportions, it is imperative that more is done to identify the genomic differences and commonalities between patients of African and European ancestry to fulfil the promise of precision oncology. Here, we summarize the utility of precision oncology approaches, with a focus on comprehensive genomic profiling (CGP) and consolidate examples of national and international consortia that are driving the field forward. We describe the importance of genomic diversity and its relevance in cancer, and propose recommendations, success factors and desired outcomes for precision oncology consortia to adopt in SSA. Through this, we hope to catalyze the initiation of such projects and to contribute to improving cancer patient outcomes in the region.

3.
BMC Endocr Disord ; 24(1): 88, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38867205

RESUMEN

BACKGROUND: Patients with primary hyperparathyroidism (PHPT) are at risk for severe hypocalcemia (SH) following parathyroidectomy (PTX), but limited data exist on the predictors of SH. We aimed to identify risk factors for early postoperative SH after PTX in patients with PHPT and to evaluate the predictive value of clinical parameters. METHODS: A retrospective review of patients with PHPT who underwent PTX between January 2010 and December 2022 was performed. A total of 46 patients were included in the study, with 15 (32.6%) experiencing postoperative SH, 19 (41.3%) having calculi in the ureter or kidney, and 37 (80.4%) having osteoporosis. Patients were divided into SH and non-SH groups based on postoperative serum calcium levels. Preoperative biochemical indicators, bone turnover markers, and renal function parameters were analyzed and correlated with postoperative SH. RESULTS: Statistically significant (P < 0.05) differences were found in preoperative serum calcium (serum Ca), intact parathyroid hormone, serum phosphorus (serum P), serum Ca/P, percentage decrease of serum Ca, total procollagen type 1 intact N-terminal propeptide, osteocalcin (OC), and alkaline phosphatase levels between the two groups. Multivariate analysis showed that serum P (odds ratio [OR] = 0.989; 95% confidence interval [95% CI] = 0.981-0.996; P = 0.003), serum Ca (OR = 0.007; 95% CI = 0.001-0.415; P = 0.017), serum Ca/P (OR = 0.135; 95% CI = 0.019-0.947; P = 0.044) and OC levels (OR = 1.012; 95% CI = 1.001-1.024; P = 0.036) were predictors of early postoperative SH. The receiver operating characteristic curve analysis revealed that serum P (area under the curve [AUC] = 0.859, P < 0.001), serum Ca/P (AUC = 0.735, P = 0.010) and OC (AUC = 0.729, P = 0.013) had high sensitivity and specificity. CONCLUSION: Preoperative serum P, serum Ca/P and osteocalcin levels may identify patients with PHPT at risk for early postoperative SH after PTX.


Asunto(s)
Hiperparatiroidismo Primario , Hipocalcemia , Paratiroidectomía , Complicaciones Posoperatorias , Humanos , Hiperparatiroidismo Primario/cirugía , Hiperparatiroidismo Primario/sangre , Hiperparatiroidismo Primario/complicaciones , Femenino , Masculino , Paratiroidectomía/efectos adversos , Persona de Mediana Edad , Factores de Riesgo , Estudios Retrospectivos , Estudios de Casos y Controles , Hipocalcemia/etiología , Hipocalcemia/sangre , Hipocalcemia/epidemiología , Hipocalcemia/diagnóstico , Complicaciones Posoperatorias/sangre , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/diagnóstico , Anciano , Calcio/sangre , Pronóstico , Biomarcadores/sangre , Adulto , Estudios de Seguimiento , Hormona Paratiroidea/sangre
4.
Org Lett ; 26(20): 4292-4296, 2024 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-38728657

RESUMEN

Here, we report a practical route to medicinally interesting lycorine congeners alongside formal syntheses of various lycorine-type natural products, including lycorine itself. The efficiency of our strategy derives from a back-to-back 5-endo-trig/6-endo-trig radical cyclization sequence, which we systematically studied both experimentally and computationally. The results of our work will facilitate future development of urgently needed antiviral therapeutics based on lycorine.

5.
J Nat Prod ; 87(6): 1521-1531, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38754059

RESUMEN

The title marine natural products have been prepared by total synthesis and in the case of congeners 3, 6, and 7 for the first time. Each of these was obtained by manipulation of readily prepared denigrin B (2). The structure, 3, assigned to denigrin C is shown to be incorrect. Reaction of compound 2 with DDQ has led, in high yield, to the related natural product spirodactylone (16), while treating the corresponding permethyl ether 15 with PIFA/BF3·Et2O provides compound 20, embodying an isomeric framework.


Asunto(s)
Alcaloides , Pirroles , Pirrolidinonas , Estructura Molecular , Alcaloides/química , Alcaloides/síntesis química , Pirroles/síntesis química , Pirroles/química , Pirrolidinonas/química , Pirrolidinonas/síntesis química , Productos Biológicos/química , Productos Biológicos/síntesis química , Biología Marina , Estereoisomerismo , Animales
6.
Foods ; 13(1)2024 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-38201202

RESUMEN

Different structural composition ratios of sucrose stearates with hydrophilic-hydrophobic balance (HLB) values ranging from 1 to 16 on lipolysis in emulsion were investigated using a simulated gastrointestinal tract (GIT). Results showed a direct correlation between the HLB values of sucrose stearates and the lipolysis rate of emulsions, and a lower HLB value led to diminished lipolysis in the GIT simulation model. Mechanism study indicated that poor emulsifying capacity of sucrose stearates and lipolysis of sucrose stearates with lower HLB value inhibited the digestive behavior of oil. In addition, monoester was mainly hydrolyzed in the gastric phase, whereas sucrose polyesters caused lipolysis in the intestinal phase using an in vitro digestive model and HPLC analysis, further suppressing lipid digestion. Furthermore, a decrease in cell cytotoxicity and proinflammatory effects on Caco-2 and Raw264.7 were observed post-digestion, respectively. This work offers important insights into the effects of the degree of esterification of sucrose stearate on lipid digestion behavior in oil-in-water emulsions.

7.
Cell Mol Biol (Noisy-le-grand) ; 69(7): 104-108, 2023 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-37715415

RESUMEN

Cancer is one of the leading causes of human death worldwide. One of the most common types of malignancy among women is breast cancer, which is the third most common cancer in the world after lung and stomach cancer. This study aimed to evaluate the expression level of Tissue Differentiation-Inducing Non-Protein Coding RNA (TINCR) in adjacent tumor and non-tumor tissues of 60 women with invasive ductal breast cancer. The relationship between TINCR expression and the clinical characteristics of patients has also been studied. For this purpose, total RNA was isolated from breast cancer patients' adjacent tumor and non-tumor tissue. RT Prime Script reagent was then used to convert total RNA to cDNA. The qRT-PCR quantified the TINCR expression level and analyzed the results by paired t-test. In addition, ROC curve analysis was used to evaluate the biomarker power of TINCR in breast cancer tumor tissues. According to the results, a decrease in the level of TINCR was obtained in the tumor tissue of breast cancer patients compared to the adjacent non-tumor tissue (P<0.001). TINCR expression was negatively correlated with tumor size and lymph node metastasis in breast cancer tumor tissue. In general, the decrease in the expression level of TINCR in the tumor tissue of breast cancer patients shows that its expression level can differentiate the adjacent tumor and non-tumor tissue from each other. In addition, TINCR has a lower expression level in breast cancer patients with large tumors, lymph node metastasis, and luminal subgroups A and B.


Asunto(s)
Neoplasias de la Mama , ARN Largo no Codificante , Femenino , Humanos , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , ADN Complementario , Metástasis Linfática , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo
8.
Materials (Basel) ; 16(9)2023 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-37176312

RESUMEN

The high-temperature compression characteristics of a Ti-55511 alloy are explored through adopting two-stage high-temperature compressed experiments with step-like strain rates. The evolving features of dislocation substructures over hot, compressed parameters are revealed by transmission electron microscopy (TEM). The experiment results suggest that the dislocations annihilation through the rearrangement/interaction of dislocations is aggravated with the increase in forming temperature. Notwithstanding, the generation/interlacing of dislocations exhibit an enhanced trend with the increase in strain in the first stage of forming, or in strain rates at first/second stages of a high-temperature compressed process. According to the testing data, an Informer deep learning model is proposed for reconstructing the stress-strain behavior of the researched Ti-55511 alloy. The input series of the established Informer deep learning model are compression parameters (compressed temperature, strain, as well as strain rate), and the output series are true stresses. The optimal input batch size and sequence length are 64 and 2, respectively. Eventually, the predicted results of the proposed Informer deep learning model are more accordant with the tested true stresses compared to those of the previously established physical mechanism model, demonstrating that the Informer deep learning model enjoys an outstanding forecasted capability for precisely reconstructing the high-temperature compressed features of the Ti-55511 alloy.

9.
Sci Rep ; 13(1): 2657, 2023 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-36788323

RESUMEN

Musical training has been associated with various cognitive benefits, one of which is enhanced speech perception. However, most findings have been based on musicians taking part in ongoing music lessons and practice. This study thus sought to determine whether the musician advantage in pitch perception in the language domain extends to individuals who have ceased musical training and practice. To this end, adult active musicians (n = 22), former musicians (n = 27), and non-musicians (n = 47) were presented with sentences spoken in a native language, English, and a foreign language, French. The final words of the sentences were either prosodically congruous (spoken at normal pitch height), weakly incongruous (pitch was increased by 25%), or strongly incongruous (pitch was increased by 110%). Results of the pitch discrimination task revealed that although active musicians outperformed former musicians, former musicians outperformed non-musicians in the weakly incongruous condition. The findings suggest that the musician advantage in pitch perception in speech is retained to some extent even after musical training and practice is discontinued.


Asunto(s)
Música , Percepción del Habla , Adulto , Humanos , Música/psicología , Percepción de la Altura Tonal , Discriminación de la Altura Tonal , Lenguaje , Habla , Estimulación Acústica/métodos
10.
Org Lett ; 25(2): 384-388, 2023 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-36606750

RESUMEN

A range of mono- and disaccharides, including glucose derivative 10, has been cleanly coupled, in the presence of a Pd catalyst, with various halogenated and structurally distinctive tropones, including "parent" compound 11, to afford the corresponding α- and ß-anomeric forms of the tropolone glycosides, e.g., 12 and 13, respectively. Varying the ligand used influences the anomer distribution significantly and such that either the α- or ß-form predominates. Notable chemo- and regioselectivities are observed when dihalogenated troponoids are employed as coupling partners.

11.
Am Surg ; 89(6): 2450-2454, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35570721

RESUMEN

BACKGROUND: To measure total type 1 serum amino-terminal propeptide procollagen (t-P1NP), ß- type 1 cross-linked C-terminal telopeptide collagen (ß-CTX), N-terminal osteocalcin (OC), and 25-(OH)-VD3 levels before parathyroidectomy (PTX) in patients with PHPT, and correlate these measurements with bone mineral density (BMD) changes at 1-year post-PTX. METHODS: Patients with primary hyperparathyroidism (PHPT) were followed from diagnosis to 12 months after surgery. Serum levels of calcium, parathyroid hormone (PTH), vitamin 25-(OH)-VD3, OC, ß-CTX, t-P1NP, and BMD were measured before and 1 year after surgery. RESULTS: One year after PTX, mean BMD increased by 25.7, 27.7, and 33.5% in the lumbar spine (L1-L4), femoral neck (FN), and greater trochanter (GT), respectively. Percent BMD change 1-year post-PTX was significant correlated with preoperative levels of ß-CTX (L1-L4: r = 0.41, P < 0.0001; FN: r = 0.54, P = 0.0003; GT: r = 0.46, P = 0.0029), t-P1NP (L1-L4: r = 0.58, P < 0.0001; FN: r = 0.73, P < 0.0001; GT: r = 0.65, P < 0.0001), 25-(OH)-VD3 (L1-L4: r = -0.33, P = 0.034; FN: r = -0.48, P = 0.002; GT: r = -0.52, P = 0.0007), and OC (L1-L4: r = 0.49, P = 0.0013; FN: r = 0.55, P = 0.0002; GT: r = 0.47, P = 0.002). CONCLUSIONS: Preoperative levels of turnover markers and BMD improvements were significantly correlated in patients with PHPT 1 year after PTX.


Asunto(s)
Densidad Ósea , Hiperparatiroidismo Primario , Humanos , Paratiroidectomía , Hormona Paratiroidea , Hiperparatiroidismo Primario/cirugía , Colágeno , Biomarcadores
12.
Glob Chang Biol ; 29(1): 126-142, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36176241

RESUMEN

Recent increases in vegetation greenness over much of the world reflect increasing CO2 globally and warming in cold areas. However, the strength of the response to both CO2 and warming in those areas appears to be declining for unclear reasons, contributing to large uncertainties in predicting how vegetation will respond to future global changes. Here, we investigated the changes of satellite-observed peak season absorbed photosynthetically active radiation (Fmax ) on the Tibetan Plateau between 1982 and 2016. Although climate trends are similar across the Plateau, we identified robust divergent responses (a greening of 0.31 ± 0.14% year-1 in drier regions and a browning of 0.12 ± 0.08% year-1 in wetter regions). Using an eco-evolutionary optimality (EEO) concept of plant acclimation/adaptation, we propose a parsimonious modelling framework that quantitatively explains these changes in terms of water and energy limitations. Our model captured the variations in Fmax with a correlation coefficient (r) of .76 and a root mean squared error of .12 and predicted the divergent trends of greening (0.32 ± 0.19% year-1 ) and browning (0.07 ± 0.06% year-1 ). We also predicted the observed reduced sensitivities of Fmax to precipitation and temperature. The model allows us to explain these changes: Enhanced growing season cumulative radiation has opposite effects on water use and energy uptake. Increased precipitation has an overwhelmingly positive effect in drier regions, whereas warming reduces Fmax in wetter regions by increasing the cost of building and maintaining leaf area. Rising CO2 stimulates vegetation growth by enhancing water-use efficiency, but its effect on photosynthesis saturates. The large decrease in the sensitivity of vegetation to climate reflects a shift from water to energy limitation. Our study demonstrates the potential of EEO approaches to reveal the mechanisms underlying recent trends in vegetation greenness and provides further insight into the response of alpine ecosystems to ongoing climate change.


Asunto(s)
Dióxido de Carbono , Ecosistema , Cambio Climático , Temperatura , Agua , Tibet
13.
J Org Chem ; 87(18): 12287-12296, 2022 09 16.
Artículo en Inglés | MEDLINE | ID: mdl-36036791

RESUMEN

The readily prepared and vinylated ß-carboline 11 has been converted over one or two steps into compounds 1-5, the structures assigned to the recently reported marine natural products orthoscuticellines A-E. The spectral data recorded on the synthetically derived compounds are fully consistent with the assigned structures and, on making allowances for variations in the pH of the medium in which the spectra of the natural products were recorded, it is concluded that the structures assigned to orthoscuticellines A-E are most likely correct. Certainly, the calculated 13C NMR spectra of the α-, γ-, and δ-carboline isomers of compounds 1-5 suggest that orthoscuticellines A-E do incorporate the assigned ß-carboline core.


Asunto(s)
Productos Biológicos , Productos Biológicos/química , Carbolinas , Isomerismo , Espectroscopía de Resonancia Magnética , Estructura Molecular
14.
ChemMedChem ; 17(18): e202200292, 2022 09 16.
Artículo en Inglés | MEDLINE | ID: mdl-35851832

RESUMEN

Oxidative stress contributes to the pathogenesis of various neurodegenerative diseases and induction of the Kelch-like ECH-associated protein 1 (Keap1)-nuclear factor erythroid 2-related factor 2 (Nrf2) pathway is a validated neuroprotective strategy. Synthetically-derived samples of members of the ribisin class of natural product together with a range of analogues were evaluated for their neuroprotective capacities. Four of the twenty-four compounds tested were found to strongly stimulate antioxidant response element-dependent transcriptional activity in human-derived SH-SY5Y cells. Further, in rat pheochromocytoma PC12 cells and mouse brain cortical cultures these compounds upregulated levels of nuclear factor erythroid 2-related factor 2 (Nrf2) and its downstream target gene products, namely heme oxygenase (HO-1) and NAD(P)H quinone reductase 1 (NQO1). Functionally speaking, the compounds conferred protection in these cell models challenged with H2 O2 . In silico molecular modeling suggests that certain of the ribisins can dock in the Nrf2-binding Kelch domain in Keap1, while cysteine labeling by biotinylated iodoacetamide suggest that cysteine residues within Keap1 react with the ribisins. It is thus proposed that the most active compounds exert their neuroprotective activities by targeting Keap1, thereby activating Nrf2 and so increasing transactivation of Nrf2-responsive genes that encode for detoxifying and antioxidant enzymes.


Asunto(s)
Productos Biológicos , Neuroblastoma , Fármacos Neuroprotectores , Animales , Antioxidantes/metabolismo , Antioxidantes/farmacología , Productos Biológicos/farmacología , Cisteína/metabolismo , Hemo Oxigenasa (Desciclizante)/metabolismo , Humanos , Yodoacetamida/farmacología , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Ratones , NAD , Factor 2 Relacionado con NF-E2/metabolismo , Fármacos Neuroprotectores/farmacología , Estrés Oxidativo , Ratas
15.
Chem Asian J ; 17(4): e202101215, 2022 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-35032358

RESUMEN

The global COVID-19 pandemic has claimed the lives of millions and disrupted nearly every aspect of human society. Currently, vaccines remain the only widely available medical means to address the cause of the pandemic, the SARS-CoV-2 virus. Unfortunately, current scientific consensus deems the emergence of vaccine-resistant SARS-CoV-2 variants highly likely. In this context, the design and development of broad-spectrum, small-molecule based antiviral drugs has been described as a potentially effective, alternative medical strategy to address circulating and re-emerging CoVs. Small molecules are well-suited to target the least-rapidly evolving structures within CoVs such as highly conserved RNA replication enzymes, and this renders them less vulnerable to evolved drug resistance. Examination of the vast literature describing the inhibition of RNA viruses by Amaryllidaceae alkaloids suggests that future, broad-spectrum anti-CoV drugs may be derived from this family of natural products.


Asunto(s)
Alcaloides de Amaryllidaceae , COVID-19 , Preparaciones Farmacéuticas , Alcaloides de Amaryllidaceae/farmacología , Antivirales/farmacología , Antivirales/uso terapéutico , Humanos , Pandemias , SARS-CoV-2
16.
Front Endocrinol (Lausanne) ; 12: 704596, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34385977

RESUMEN

Background: The staging system for patients with anaplastic thyroid cancer (ATC) was updated in the 8th edition of the American Joint Committee on Cancer Staging Manual. A cut-off age of 55 years was stipulated as a prognostic factor for differentiated thyroid cancer; however, age was not considered for ATC patients. To this end, this study investigated the relationship between age at diagnosis and prognosis of ATC patients. Methods: The clinical information on ATC patients was acquired from the Surveillance, Epidemiology, and End Results Program public database. Youden's index and X-tile analyses were used to calculate the high-point age at diagnosis associated with prognosis. Cox proportional hazards models, Kaplan-Meier curves, and 1000-person-year were then used for verifying the accuracy of the high-point age. Results: After inclusion/exclusion criteria was applied, 586 patients were included in this study. The high-point age was determined to be 70 years by both the Youden's index and X-tile plot methods. The hazard ratio was 1.662 (95% confidence interval [CI]: 1.321-2.092), indicating that there was an increased risk of poor prognosis for patients > 70 years of age. The cancer-specific mortality rates per 1000-person-years for patients ≤ and > 70 years-old were 949.980 (95% CI: 827.323-1090.822) and 1546.667 (95% CI: 1333.114-1794.428), respectively. P-values were < 0.001 for the results shown above. Conclusion: Our study found that age influenced the prognosis of ATC patients. Furthermore, we determined that the high-point age at diagnosis was 70 years and that > 70 years of age was associated with a poor prognosis. These results provide a useful addition to the staging manual and can improve the diagnosis, treatment strategies and prognosis of ATC patients.


Asunto(s)
Carcinoma Anaplásico de Tiroides/patología , Neoplasias de la Tiroides/patología , Tiroidectomía/mortalidad , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Tasa de Supervivencia , Carcinoma Anaplásico de Tiroides/cirugía , Neoplasias de la Tiroides/cirugía
17.
Aesthetic Plast Surg ; 45(2): 564-569, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-31637503

RESUMEN

BACKGROUND: The epicanthal fold is ordinary in the eyelids of Asians, and the aesthetic appearance of eyelid surgery could be reduced and undermined; thus, medial epicanthoplasty is commonly performed to eliminate the effect of the epicanthal fold with less scarring. At present, there are a lot of techniques that have been described for the treatment of epicanthal fold. The potential problems, however, such as visible scar or under correction in the medial canthus area are challenges to surgeons. The purpose of our study was to explore a novel and individualized design using a modified rectangle flap with acceptable functional and aesthetic outcomes. METHODS: From January 2017 to January 2018, epicanthoplasty was performed for 40 patients by using a modified rectangle flap. All patients underwent double-eyelid surgery at the same time when they needed it. The evaluation criteria included the intercanthal distance (ICD), interpupillary distance (IPD), the ratio of ICD to IPD (ICD ratio), scar visibility, and cosmetic results. RESULTS: From January 2017 to January 2018, the modified rectangle flap method was carried out on 40 patients, who were evaluated at follow-up from 7 to 15 months. The average intercanthal length was 36.9 ± 2.2 mm preoperatively and decreased significantly to 31.5 ± 1.8 mm postoperatively, 7 months after the surgery (P < 0.01). The excellent cosmetic results, in terms of an open medial canthus, were observed during follow-up periods, with no definite recurrence, hypertrophic scar, or injury of the lacrimal apparatus. The inner canthus and lacrimal caruncle are fully exposed with an invisible scar. Both the patients and the surgeon judged that the aesthetic outcomes were excellent or good. CONCLUSIONS: This modified rectangular flap is an effective and personalized method of correcting the medial folds that leave no additional scar in the medial canthal area, and the procedure meets the patient's aesthetic expectations. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .


Asunto(s)
Blefaroplastia , Pueblo Asiatico , Estudios de Cohortes , Párpados/cirugía , Humanos , Estudios Retrospectivos , Resultado del Tratamiento
18.
Polymers (Basel) ; 11(5)2019 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-31075895

RESUMEN

In this work, polymers of poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-triphenylamine] with side chains containing: pyrene (C1), diphenyl (C2), naphthalene (C3), and isopropyl (C6) structures were synthesized via a Suzuki coupling reaction. The structures were verified using NMR and cyclic voltammetry measurements provide the HOMO and LUMO of the polymers. The polymer with pyrene (C1) and naphthalene (C3) produced photoluminescence in the green while the polymer with the side chain containing diphenyl (C2) and isopropyl (C6) produce dual emission peaks of blue-green photoluminescence (PL). In order to examine the electroluminescence properties of the polymers, the solutions were spin-coated onto patterned ITO anode, dried, and subsequently coated with an Al cathode layer to form pristine single layer polymer LEDs. The results are compared to a standard PFO sample. The electroluminescence spectra resemble the PL spectra for C1 and C3. The devices of C2, C3, and C6 exhibit voltage-dependent EL. An additional red emission peak was detected for C2 and C6, resulting in spectra with peaks at 435 nm, 490 nm, and 625 nm. The effects of the side chains on the spectral characteristics of the polymer are discussed.

19.
Mol Neurobiol ; 56(10): 7222-7233, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31001802

RESUMEN

The cholinergic neurons in the nucleus basalis of Meynert (NBM) are among the first group of neurons known to become degenerated in Alzheimer's disease, and thus the NBM is proposed to be involved in learning and memory. The marginal division (MrD) of the striatum is a newly discovered subdivision at the ventromedial border of the mammalian striatum and is considered to be one part of the ventral striatum involved in learning and memory. The present study provided evidence to support the hypothesis that the MrD and the NBM were structurally connected at cellular and subcellular levels with functional implications in learning and memory. First, when wheat germ agglutinin-conjugated horseradish peroxidase (WGA-HRP) was stereotaxically injected into the NBM, fusiform neurons in the MrD were retrogradely labeled with WGA-HRP gray-blue particles and some of them were double stained in brown color by AchE staining method. Thus, cholinergic neurons of the MrD were shown to project to the neurons in the NBM. Second, in anterograde tract-tracing experiments where WGA-HRP was injected to the MrD, the labeled WGA-HRP was found to be anterogradely transported in axons from the MrD to the synaptic terminals with dendrites, axons, and perikaryons of the cholinergic neurons in the NBM when observed under an electronic microscope, indicating reciprocal structural connections between the MrD and the NBM. Third, when bilateral lesions of the MrD were injured with kainic acid in rats, degenerative terminals were observed in synapses of the NBM by an electronic microscope and severe learning and memory deficiency was found in these rats by the Y-maze behavioral test. Our results suggest reciprocal cholinergic connections between the MrD of the ventral striatum and the NBM, and implicate a role of the MrD-NBM pathway in learning and memory. The efferent fibers of cholinergic neurons in the NBM mainly project to the cortex, and severe reduction of the cholinergic innervation in the cortex is the common feature of Alzheimer's patients. The newly discovered cholinergic neural pathway between the MrD of the ventral striatum and the NBM is supposed involved in the memory circuitries of the brain and probably might play a role in the pathogenesis of the Alzheimer's disease.


Asunto(s)
Núcleo Basal de Meynert/fisiología , Memoria/fisiología , Vías Nerviosas/fisiología , Estriado Ventral/fisiología , Acetilcolinesterasa/metabolismo , Animales , Núcleo Basal de Meynert/ultraestructura , Conducta Animal , Peroxidasa de Rábano Silvestre/metabolismo , Ácido Kaínico , Masculino , Neuronas/metabolismo , Ratas Sprague-Dawley , Estriado Ventral/ultraestructura , Aglutininas del Germen de Trigo/metabolismo
20.
Int J Clin Exp Pathol ; 11(3): 1811-1817, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-31938288

RESUMEN

Objective: To investigate the effects of microRNA-126 (miR-126) overexpression on hemangioma endothelial cells (HemECs). Methods: An adenoviral vector containing the miR-126 gene was constructed. HemECs were passaged and expanded and adenovirus-mediated green fluorescent protein (GFP) gene was transfected in vitro. The infection efficiency of adenovirus vector to HemECs was tested by Ad-GFP infection procedure. GFP expression efficiency was observed using a fluorescence microscope and flow cytometry was used to determine the best virus multiplicity of infection (MOI). The experiment was divided into the blank group, AD-GFP group, and AD-miR-126 group. The miR-126 group was transfected into HemECs in vitro with adenovirus-mediated miR-126 gene under optimal MOI conditions. RT-PCR was applied to detect expression of miR-126 gene in cells. The influence of recombinant adenovirus on cell activity was evaluated by CCK-8 assay. Flow cytometry was utilized to detect cell cycle and apoptosis. Results: HemECs could be effectively infected by adenovirus containing GFP gene in vitro, the transfection efficiency had the dose-effect relationship with multiplicities of infection (MOI). When MOI was 400, the infection efficiency was more than 90%. miR-126 expression in HemECs was significantly enhanced in miR-126 group (P<0.05). Compared to the control group, cell proliferation was significantly enhanced (P<0.05) and induced S-phase arrest significantly (P<0.05) when miR-126 was upregulated. In addition, compared with the control group, the early apoptotic rate was significantly decreased by upregulating miR-126 (P<0.05). Conclusion: miR-126 overexpression can successfully promote proliferation and inhibit apoptosis of HemECs. This work will provide the theoretical and experimental basis for further transplantation study in vivo.

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