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1.
Anal Chem ; 95(51): 18850-18858, 2023 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-38091507

RESUMEN

The development of chiral alignment media for measuring anisotropic NMR parameters provides an opportunity to determine the absolute configuration of chiral molecules without the need for derivatization. However, chiral alignment media with a high and robust enantiodiscriminating property for a wide range of chiral molecules are still scarce. In this study, we synthesized cholesterol-end-functionalized helical polyisocyanides from a chiral monomer using a cholesterol-based alkyne-Pd(II) initiator. These stereoregular polyisocyanides form stable and weak anisotropic lyotropic liquid crystals (LLCs) in dichloromethane systems, exhibiting highly optical activities in both single left- and right-handed helices. The preparation process of the media was straightforward, and the aligning property of the LLCs could be controlled by adjusting the concentration and temperature. Using the chiral polyisocyanides, we extracted the residual dipolar coupling for an enantiomeric pair of isopinocampheol (IPC), as well as a number of pharmaceutical molecules, demonstrating excellent enantiodiscriminating properties for a broad range of chiral compounds.

2.
Int J Ophthalmol ; 16(12): 2011-2017, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38111928

RESUMEN

AIM: To describe the outcome of using low-dose laser cycloplasty (LCP) in chronic angle-closure glaucoma (CACG). METHODS: A retrospective case series. Medical charts of CACG patients who underwent LCP in the Eye Hospital of Wenzhou Medical University were reviewed. The main outcomes included intraocular pressure (IOP), the number of glaucoma medication, anterior segment parameters and surgery-related complications. RESULTS: A total of 7 eyes of 7 CACG patients (age 38.9±11.0y) underwent LCP with a mean follow-up of 27.1±13.7mo (range 16-48mo). Following LCP, mean IOP and glaucoma medications decreased from 26.1±6.1 mm Hg with 3.1±1.1 glaucoma medications pre-treatment to 14.9±3.1 mm Hg (P=0.027) with 0.4±1.1 glaucoma medications (P=0.001) at final follow-up. The anterior chamber depth (ACD), angle opening distance500 and trabecular-iris angle increased from 1.65±0.33 mm, 0.05 mm (range 0-0.30 mm) and 5.1° (range, 0-31.97°) at baseline to 1.98±0.43 mm (P=0.073), 0.53 mm (range 0.42-0.91 mm, P=0.015), 45.9° (range, 40.2°-59.4°, (P=0.015) in the long-term follow-up, respectively. The deepening of ACD and reopening of anterior chamber angle (ACA) was observed in 6 eyes (85.7%). CONCLUSION: LCP is a promising treatment option for patients with CACG via reducing IOP and glaucoma medication without serious complications. In addition, LCP can bring a significant deepening in ACD and reopening of ACA.

3.
ACS Omega ; 8(33): 30747-30756, 2023 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-37636964

RESUMEN

Garbractin A (1), a structurally complicated polycyclic polyprenylated acylphloroglucinol (PPAP) with an unprecedented 4,11-dioxatricyclo[4.4.2.01,5] dodecane skeleton, was isolated from the fruits of Garcinia bracteata, along with five new biosynthetic analogues named garcibracteatones A-E (2-6). Their structures containing absolute configurations were revealed using spectroscopic data, the residual dipolar coupling-enhanced NMR approach, and quantum chemical calculations. The antihyperglycemic effect of these PPAPs (1-6) was evaluated using insulin-resistant HepG2 cells (IR-HepG2 cells) induced through palmitic acid (PA). Compounds 1, 3, and 4 were found to significantly promote glucose consumption in the IR-HepG2 cells and, therefore, may hold potential as candidates for treating hyperglycemia.

4.
Nanoscale ; 15(17): 7820-7828, 2023 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-37051680

RESUMEN

Residual Dipolar Coupling (RDC), acquired relying on weakly alignment media, is highly valuable for the structural elucidation of organic molecules. Arising from the striking features of no background signals and low critical concentrations, two-dimensional (2D) liquid crystals (LCs) show the clear advantages of acting as alignment media to measure RDCs. So far, creating multisolvent compatible 2D LC media through a simple and versatile method is still formidably challenging. Herein, we report the rapid creation of aligned media based on the Ti3C2Tx MXene, which self-aligned in multiple co-solvents including CH3OH-H2O, DMSO-H2O, DMF-H2O, and acetone-H2O. We demonstrated the applicability of these aligned media for the RDC measurement of small organic molecules with different polarities and solubilities. Notably, Ti3C2Tx MXene LCs without chemical modification enabled RDC measurements on aromatic molecules. The straightforward preparation of Ti3C2Tx media and its compatibility with multiple solvents will push RDC measurement as a routine methodology for structural elucidation. It may also facilitate the investigation of solvation effects on conformational dynamics.

5.
Chronobiol Int ; 40(3): 353-360, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36912010

RESUMEN

The objective of this scoping review was to synthesize the available evidence and evaluate the effectiveness of chronoradiotherapy interventions in cervical cancer patients. This scoping review was performed by searching in the PubMed, Cochrane Library, Embase, Web of Science, Scopus, Cumulative Index to Nursing and Allied Health Literature (CINAHL), China National Knowledge Infrastructure (CNKI), Wanfang, Wenpu, and Chinese Biomedical Literature (CBM) databases. Databases were searched for studies published in English or Chinese from inception to 21 May 2021, and reference lists of relevant reports were scanned. Two investigators independently screened eligible studies in accordance with predetermined eligibility criteria and extracted data. The included studies were summarized and analyzed. Five studies including a total of 422 patients with cervical cancer were included in the scoping review; four studies were Chinese, and one was Indian. Main themes identified included the efficiency of chronoradiotherapy and relevant toxic and side effects, including diarrhea toxicity, hematologic toxicity, myelosuppression, gastrointestinal mucositis, and skin reactions. Administration of radiotherapy at different times of the day resulted in similar efficacy. However, the toxic side effects of morning radiotherapy (MR) and evening radiotherapy (ER) differed, with radiotherapy in the evening leading to more severe hematologic toxicity and myelosuppression. There were conflicting conclusions about gastrointestinal reactions with chronoradiotherapy, and further studies are needed. Radiation responses may be associated with circadian genes, through the influence of cell cycles and apoptosis.


Asunto(s)
Neoplasias del Cuello Uterino , Femenino , Humanos , Neoplasias del Cuello Uterino/radioterapia , Ritmo Circadiano , China
6.
Angew Chem Int Ed Engl ; 62(15): e202300773, 2023 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-36806846

RESUMEN

Tricrilactones A-H (1-8), a new family of oligomeric 10-membered macrolides featuring collectively five unique ring skeletons, were isolated from a hitherto unexplored fungus, Trichocladium crispatum. Compounds 1 and 7 contain two unconventional bridged (aza)tricyclic core skeletons, 2, 3, 5, and 6 share an undescribed tetracyclic 9/5/6/6 ring system, 4 bears an uncommon 9/5/6/10/3-fused pentacyclic architecture, and 8 is a dimer bridged by an unexpected C-C linkage. Their structures, including absolute configurations, were elucidated by spectroscopic analysis, quantum chemical calculations, and X-ray diffraction analysis. Importantly, the absolute configuration of the highly flexible side chain of 1 was resolved by the asymmetric synthesis of its four stereoisomers. The intermediate-trapping and isotope labeling experiments facilitated the proposal of the biosynthetic pathway for these macrolides. In addition, their antiosteoporosis effects were evaluated in vivo (zebrafish).


Asunto(s)
Chaetomium , Macrólidos , Animales , Estructura Molecular , Macrólidos/química , Pez Cebra , Antibacterianos/farmacología
7.
Eur J Oncol Nurs ; 63: 102258, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36821887

RESUMEN

OBJECTIVE: Breast cancer-related lymphedema (BCRL) is a common post-operative complication in patients with breast cancer. Here, we sought to develop and validate a predictive model of BCRL in Chinese patients with breast cancer. METHODS: Clinical and demographic data on patients with breast cancer were collected between 2016 and 2021 at a Cancer Hospital in China. A nomogram for predicting the risk of lymphedema in postoperative patients with breast cancer was constructed and verified using R 3.5.2 software. Model performance was evaluated using area under the ROC curve (AUC) and goodness-of-fit statistics, and the model was internally validated. RESULTS: A total of 1732 postoperative patients with breast cancer, comprising 1212 and 520 patients in the development and validation groups, respectively, were included. Of these 438 (25.39%) developed lymphedema. Significant predictors identified in the predictive model were time since breast cancer surgery, level of lymph node dissection, number of lymph nodes dissected, radiotherapy, and postoperative body mass index. At the 31.9% optimal cut-off the model had AUC values of 0.728 and 0.710 in the development and validation groups, respectively. Calibration plots showed a good match between predicted and observed rates. In decision curve analysis, the net benefit of the model was better between threshold probabilities of 10%-80%. CONCLUSION: The model has good discrimination and accuracy for lymphedema risk assessment, which can provide a reference for individualized clinical prediction of the risk of BCRL. Multicenter prospective trials are required to verify the predictive value of the model.


Asunto(s)
Linfedema del Cáncer de Mama , Neoplasias de la Mama , Linfedema , Humanos , Femenino , Neoplasias de la Mama/radioterapia , Estudios Prospectivos , Factores de Riesgo , Linfedema/etiología , Estudios Retrospectivos
8.
Front Oncol ; 12: 1021453, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36457490

RESUMEN

Objectives: To investigate the short-term efficacy and radiotoxicity 3.543of chronoradiotherapy in patients with cervical cancer. We also examined the overall symptom score and quality of life (QOL) of patients who underwent morning radiotherapy and evening radiotherapy. Methods: We conducted a multicenter randomized controlled trial to compare the effects of morning radiotherapy (9:00-11:00 AM) with evening radiotherapy (7:00-9:00 PM) in cervical cancer patients receiving radiotherapy. From November 2021 to June 2022, 114 cervical cancer patients admitted to eight cancer center hospitals in Tianjin, Chongqing, Hubei, Shanxi, Shandong, Shaanxi, Hebei, and Cangzhou were randomly divided into the morning radiotherapy group (MG; N = 61) and the evening radiotherapy group (EG; N = 53). The short-term efficacy of radiotherapy on cervical cancer patients at different time points and the occurrence of radiotoxicity were explored after patients had undergone radiotherapy. Results: The total effective response (partial remission [PR] + complete remission [CR]) rate was similar across the two groups (93.5% vs. 96.3%, p > 0.05). However, the incidence of bone marrow suppression and intestinal reaction in the two groups were significantly different (p < 0.05). The patients in the MG had significantly higher Anderson symptom scores than patients in the EG (21.64 ± 7.916 vs. 18.53 ± 4.098, p < 0.05). In terms of physical activity, functional status, and overall QOL, the MG had significantly lower scores than the EG (p < 0.05). No other measures showed a significant difference between the groups. Conclusion: The radiotherapy effect of the MG was consistent with that of the EG. The incidence of radiation enteritis and radiation diarrhea in the MG was significantly higher than that in the EG; however, bone marrow suppression and blood toxicity in the EG were more serious than in the MG. Because of the small sample size of the study, we only examined the short-term efficacy of radiotherapy. Therefore, further clinical trials are needed to verify the efficacy and side effects of chronoradiotherapy. Clinical Trial Registration: http://www.chictr.org.cn/searchproj.aspx, Registration Number: ChiCTR2100047140.

9.
ACS Nano ; 16(4): 5454-5462, 2022 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-35311253

RESUMEN

The formation of lyotropic liquid crystals (LCs) in two-dimensional (2D) colloidal dispersions enables the production of mesoscopic/macroscopic ordered materials from nanoscale building blocks. In contrast to graphene oxide (GO) LCs, the practical applications of MXene LCs are less exploited. This study bridges the gap by utilizing a simple and versatile fabrication method to prepare Ti3C2Tx MXene LC that can be applied as a background-free alignment medium for the residual dipolar coupling (RDC) measurement of organic molecules. Ti3C2Tx LC displays the size- and concentration-dependent alignment degree. Ti3C2Tx nanoflakes with an average size of around 600 nm can provide the quadrupolar 2H splitting of 71 Hz at a concentration of 50 mg/mL and show excellent fluidity at such a high concentration. Compared with other alignment media, Ti3C2Tx LC exhibits the features of no-background and narrow line broadening, which actualizes the acquirement of clean and high-quality NMR spectra for the accurate RDC extraction. Notably, the alignment of LCs is determined to be maintainable in the redispersed solution after freeze-drying, providing the great convenience for the preparation of alignment Ti3C2Tx media, long-term sample preservation, and quantitative evaluation of alignment degree. Meanwhile, the alignment LC media for RDC measurement can be established in other MXenes such as Ti2CTx and Ti3CNTx. Collectively, our findings demonstrate the potential of creating various alignment media from the fascinating MXene family.

10.
J Mater Chem B ; 10(12): 2047-2056, 2022 03 23.
Artículo en Inglés | MEDLINE | ID: mdl-35254366

RESUMEN

Nano drug delivery systems are a research hotspot in the field of tumor therapy. In this work, molybdenum disulfide (MoS2) nanosheets were selected as the base material and a natural red blood cell membrane (RBC membrane) was camouflaged on the nanosheets to enhance their dispersibility and tumor targeting profile. The camouflaged molybdenum disulfide nanocomposites (MoS2-RBC) were successfully prepared by incubation. This nanomaterial has good stability and biocompatibility with a good immune evasion ability. MoS2 has a large specific surface area and unique layered structure, which provides favorable conditions for the loading of anticancer drugs. Adriamycin hydrochloride (DOX) was used as the model drug and the drug loading capacity was 98.98%. In the tumor microenvironment, the red cell membrane modified MoS2 drug delivery system (MoS2-RBC-DOX) showed obvious pH-dependent release behavior. In addition, the excellent photothermal properties of MoS2 are conducive to the release of drugs, thus improving the efficacy. According to the cell tests, MoS2-RBC had no cytotoxicity toward tumor cells, while DOX loading induced dose-dependent cytotoxicity. Furthermore, MoS2-RBC has a favorable photothermal effect, and chemotherapy combined with photothermal therapy is more effective than any single therapy. In vivo fluorescence imaging and in vivo photothermal imaging experiments confirmed the promoted accumulation of carrier materials at the tumor site after RBC membrane modification. Finally, in vivo antitumor studies showed that photothermal/chemotherapy combined with MoS2-RBC could completely inhibit tumor growth, and the body weights of mice fluctuated within the normal range without significant decrease. In summary, this MoS2-RBC drug delivery system provides a safe, rapid and effective option for future treatment of breast cancer.


Asunto(s)
Neoplasias de la Mama , Nanocompuestos , Neoplasias , Animales , Biomimética , Neoplasias de la Mama/terapia , Supervivencia Celular , Liberación de Fármacos , Membrana Eritrocítica , Ratones , Molibdeno/química , Molibdeno/farmacología , Nanocompuestos/química , Terapia Fototérmica , Microambiente Tumoral
11.
BMC Pregnancy Childbirth ; 21(1): 551, 2021 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-34384374

RESUMEN

BACKGROUND: We encourage Hepatitis B virus-infected mothers to breastfeed postpartum, even when continuing pregnancy category B nucleos(t)ide analogs (NAs) treatment. However, a large proportion of the Hepatitis B virus-infected mothers were noncompliant with this breastfeeding recommendation. This study aimed to investigate the factors associated with noncompliance with breastfeeding recommendation in Hepatitis B virus-infected mothers who had received NAs treatment during pregnancy. METHODS: A total of 155 mothers with chronic hepatitis B receiving NAs treatment for preventing mother-to-child transmission during the late gestation period were included and divided into exclusive breastfeeding (n = 63), mixed feeding (n = 34), and artificial feeding (n = 58) groups according to the postpartum feeding methods. Independent variables associated with feeding methods were analyzed using logistic regression analysis. RESULTS: Compared to the breastfeeding and mixed feeding groups, the artificial feeding group had significantly more multiparity, later postpartum timing of stopping NAs treatment, and a lower proportion of having knowledge of NAs medications (all P < 0.05). In addition, multivariable logistic regression analysis confirmed that multiparity, later postpartum timing of stopping NAs treatment, and lacking knowledge of medication were independent factors associated with noncompliance with breastfeeding recommendation. CONCLUSIONS: Hepatitis B virus-infected mothers who stopped NAs treatment at late postpartum period or had less knowledge of medication were more likely to be noncompliant with breastfeeding recommendation. Strengthening health education for participants taking NAs may be an important method to improve compliance with breastfeeding recommendation.


Asunto(s)
Antivirales/uso terapéutico , Lactancia Materna , Nucleósidos/uso terapéutico , Cooperación del Paciente , Periodo Posparto , Telbivudina/uso terapéutico , Tenofovir/uso terapéutico , Adulto , China/epidemiología , Femenino , Hepatitis B Crónica/prevención & control , Humanos , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Embarazo , Complicaciones Infecciosas del Embarazo/prevención & control , Estudios Retrospectivos , Factores de Riesgo
12.
Inorg Chem ; 60(11): 8331-8338, 2021 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-34038101

RESUMEN

Controlled hydration leads to four derivatives of a metal-organic framework consisting of cadmium ions, N1,N1,N4,N4-tetrakis(4-(pyridin-4-yl)phenyl)benzene-1,4-diamine, and coordinated and free nitrates. The balance of water coordination and the multitude of bonding of the weakly coordinated nitrate lead to a progressive change in the coordination number of the Cd2+ ions from eight to seven to six without great perturbation to the 4-fold interpenetration three-dimensional framework.

13.
Colloids Surf B Biointerfaces ; 189: 110873, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32113085

RESUMEN

In this study, we confirmed that protamine-templated gold nanoclusters (PRT-AuNCs) exhibit aggregation-induced emission properties (AIE-PRT-AuNCs). 1-Hydroxypyrene (1-OHPy) further induced the aggregation of AIE-PRT-AuNCs via hydrogen bonding and electrostatic and hydrophobic interactions, resulting in the aggregation-induced photoluminescence enhancement of AIE-PRT-AuNCs. 9-Hydroxyphenanthrene was able to decrease the background signal, thus increasing the sensitivity of the method. Based on these findings, a cost-effective, highly sensitive and selective strategy was proposed for the quantitative detection of 1-OHPy. This method displayed a wide linear range of 0.924 - 74.1 nmol/L with a low detection limit of 0.277 nmol/L, showing great potential for the monitoring of 1-OHPy in human urine. This strategy may provide a theoretical basis for future studies of the AIE properties of metal nanoclusters and their applications in the field of chemical and biological sensing.


Asunto(s)
Oro/química , Luminiscencia , Nanopartículas del Metal/química , Fenantrenos/química , Protaminas/química , Pirenos/orina , Humanos , Tamaño de la Partícula , Procesos Fotoquímicos , Espectrometría de Fluorescencia , Propiedades de Superficie
14.
Mikrochim Acta ; 186(11): 700, 2019 10 16.
Artículo en Inglés | MEDLINE | ID: mdl-31617023

RESUMEN

This work describes a method for the determination of 1-hydroxypyrene (OH-Py) via aggregation-induced quenching of the emission of protamine-coated gold nanoclusters using 9-hydroxyphenanthrene (OH-Phe) as a sensitizer to boost the emission efficiency of nanoprobe. Under optimum conditions, the drop in fluorescence intensity at excitation/emission wavelengths of 300/596 nm is proportional to the concentrations of OH-Py in the range from 1.0 to 65 nM. The relative standard deviations are 4.2, 2.4 and 1.9% (for n = 11) at concentration levels of 8.0, 32 and 48 nM of OH-Py, respectively. The detection limit is 0.3 nM which is much lower than that of some previously reported methods. The recoveries from urine samples spiked with OH-Py ranged between 94.4 and 98.8%. Graphical abstract 1-Hydroxypyrene (OH-Py) can trigger the aggregation of protamine-gold nanoclusters (PRT-AuNCs), resulting in the emission quenching of PRT-AuNCs. 9-Hydroxyphenanthrene (OH-Phe) can boost the emission efficiency of nanoprobe. Thereby, a highly sensitive assay of OH-Py was established.

15.
Inorg Chem ; 57(24): 15040-15043, 2018 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-30507179

RESUMEN

The subtle balance of the metrics of the highly supple 5,5'-pyridyl-3,3'-bis-1 H-pyrazolate and the variable coordination numbers of Cu(I) favor the stabilization of a [4 × 4] grid complex with all Cu(I). It has numerous cuprophilic bonds (Cu···Cu = 2.56-3.02 Å), and consequently, exhibits strong orange luminescence that fades upon insertion of solvents without loss of crystallinity.

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