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1.
J Org Chem ; 88(17): 12257-12264, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37579280

RESUMEN

A transition-metal-free hydrosilylation of allenes is reported herein by using commercially available lithium triethylborohydride (LiHBEt3) as the catalyst. Both mono- and disubstituted allenes could be hydrosilylated with primary or secondary silanes effectively. This reaction represents an environmental and economic method to prepare (E)-allylsilanes in good yields along with decent selectivities.

2.
World J Clin Cases ; 10(22): 7728-7737, 2022 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-36158510

RESUMEN

BACKGROUND: Radiation therapy, especially the development of linear accelerators, plays a key role in cancer management. The fast-rotating coplanar O-ring Halcyon Linac has demonstrated many advantages. The previous literature has mainly focused on the machine parameters and plan quality of Halcyon, with a lack of relevant research on its clinical application. AIM: To evaluate the clinical performance of the O-ring Halcyon treatment system in a real-world application setting. METHODS: Data from sixty-one patients who were treated with the Halcyon system throughout the entire radiotherapy process in Peking Union Medical College Hospital between August 2019 and September 2020 were retrospectively reviewed. We evaluated the target tumour response to radiotherapy and irradiation toxicity from 1 to 3 mo after treatment. Dosimetric verification of Halcyon plans was performed using a quality assurance procedure, including portal dosimetry, ArcCHECK and point dose measurements for verification of the system delivery accuracy. RESULTS: Of the 61 patients in the five groups, 16, 12, 7 and 26 patients had complete response, partial response, progressive disease and stable disease, respectively. No increase in the irradiated target tumour volume was observed when separately evaluating the local response. Regarding irradiation toxicity, no radiation-induced deaths were observed. Thirty-eight percent (23/61 patients) had no radiation toxicity after radiotherapy, 56% (34/61 patients) experienced radiation toxicity that resolved after treatment, and 6% (4/61 patients) had irreversible adverse reactions. The average gamma passing rates with a 2% dose difference and 2-mm distance to agreement for IMRT/VMAT/SRT plans were ArcCHECK at 96.4% and portal dosimetry at 96.7%, respectively. All of the validated clinical plans were within 3% for point dose measurements, and Halcyon's ArcCHECK demonstrated a high pass rate of 99.1% ± 1.1% for clinical gamma passing criteria of 3%/3 mm. CONCLUSION: The O-ring Halcyon Linac could achieve a better therapeutic effect on the target volume by providing accurate treatment delivery plans with tolerable irradiation toxicity.

3.
World J Oncol ; 13(3): 145-154, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35837318

RESUMEN

Background: The aim of the study was to evaluate the efficacy of abdominopelvic lymphatic drainage area irradiation (APLN), instead of whole abdominal radiotherapy (WART), in the consolidative radiotherapy of advanced ovarian carcinoma patients. Methods: We conducted a retrospective analysis collecting 99 patients with locally advanced ovarian cancer treated by APLN with 45 - 50 Gy/25- 28 fractions/5-7#, instead of WART. We evaluated the clinical outcome of APLN. Five patients were selected for dosimetric verifications verses WART (30 Gy/20 fractions). The normal tissue complication probability (NTCP) was calculated for the two treatment methods. Results: The mean follow-up time was 64.10 months (5.5 - 113.2 months), after APLN consolidative radiotherapy, 1-, 3-, and 5-year overall survival (OS) was 87.9%, 81.3%, and 61.5%, median disease-free survival (DFS) was 40.8 months, 5-year local recurrence free survival (LRFS) was 75.9%, and 5-year distant metastasis free survival (DMFS) was 49.2%. One patient died due to intestinal perforation. Local recurrence in the area between WART and APLN was rare (3/99 patients). The number of surgical procedures < 2 was an independent risk factor for LRFS (P = 0.023). Dosimetric comparison showed that comparing with WART, APLN significantly reduced the organ at risk (OAR) dose: 25.37 ± 3.63 Gy (25%) for liver, 8.77 ± 5.03 Gy (25%) for kidney, 8.14 ± 1.51 Gy (25%) for small intestine, etc. NTCP was reduced by 0.04-1.04% for liver, kidney, and small intestine. Conclusion: For consolidative radiotherapy in locally advanced ovarian cancer, APLN (intensity-modulated radiotherapy 45 - 50 Gy/25 - 28 fractions) could be an alternative to WART, resulting in excellent LRFS and DFS, with acceptable toxicities, comparing with previous literature reports. Dosimetric analysis also showed the benefits of APLN in NTCP.

4.
J Org Chem ; 87(2): 1589-1597, 2022 01 21.
Artículo en Inglés | MEDLINE | ID: mdl-34967640

RESUMEN

A general and efficient palladium catalyzed hydroalkynylation of allenes was developed to produce synthetically versatile (E)-1,3-enyne derivatives with high regio- and stereoselectivity. This catalytic system proceeded under mild conditions and was compatible with a broad range of substrates, especially for allenes without electron-bias groups. This work further broadens the synthetic potential of these scaffolds in organic synthesis and medicinal chemistry.


Asunto(s)
Alcadienos , Paladio , Catálisis , Estereoisomerismo
5.
BMC Cardiovasc Disord ; 21(1): 202, 2021 04 21.
Artículo en Inglés | MEDLINE | ID: mdl-33882836

RESUMEN

BACKGROUND: Several studies have shown that N-terminal pro-B-type natriuretic peptide (NT-proBNP) is strongly correlated with the complexity of coronary artery disease and the prognosis of patients with non-ST segment elevation acute coronary syndrome (NSTE-ACS), However, it remains unclear about the prognostic value of NT-proBNP in patients with NSTE-ACS and multivessel coronary artery disease (MCAD) undergoing percutaneous coronary intervention (PCI). Therefore, this study aimed to reveal the relationship between NT-proBNP levels and the prognosis for NSTE-ACS patients with MCAD undergoing successful PCI. METHODS: This study enrolled 1022 consecutive NSTE-ACS patients with MCAD from January 2010 to December 2014. The information of NT-proBNP levels was available from these patients. The primary outcome was in-hospital all-cause death. In addition, the 3-year follow-up all-cause death was also ascertained. RESULTS: A total of 12 (1.2%) deaths were reported during hospitalization. The 4th quartile group of NT-proBNP (> 1287 pg/ml) showed the highest in-hospital all-cause death rate (4.3%) (P < 0.001). Besides, logistic analyses revealed that the increasing NT-proBNP level was robustly associated with an increased risk of in-hospital all-cause death (adjusted odds ratio (OR): 2.86, 95% confidence interval (CI) = 1.16-7.03, P = 0.022). NT-proBNP was able to predict the in-hospital all-cause death (area under the curve (AUC) = 0.888, 95% CI = 0.834-0.941, P < 0.001; cutoff: 1568 pg/ml). Moreover, as revealed by cumulative event analyses, a higher NT-proBNP level was significantly related to a higher long-term all-cause death rate compared with a lower NT-proBNP level (P < 0.0001). CONCLUSIONS: The increasing NT-proBNP level is significantly associated with the increased risks of in-hospital and long-term all-cause deaths among NSTE-ACS patients with MCAD undergoing PCI. Typically, NT-proBN P > 1568 pg/ml is related to the all-cause and in-hospital deaths.


Asunto(s)
Enfermedad de la Arteria Coronaria/terapia , Péptido Natriurético Encefálico/sangre , Infarto del Miocardio sin Elevación del ST/terapia , Fragmentos de Péptidos/sangre , Intervención Coronaria Percutánea , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Causas de Muerte , Enfermedad de la Arteria Coronaria/sangre , Enfermedad de la Arteria Coronaria/diagnóstico , Enfermedad de la Arteria Coronaria/mortalidad , Femenino , Mortalidad Hospitalaria , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio sin Elevación del ST/sangre , Infarto del Miocardio sin Elevación del ST/diagnóstico , Infarto del Miocardio sin Elevación del ST/mortalidad , Intervención Coronaria Percutánea/efectos adversos , Intervención Coronaria Percutánea/mortalidad , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento
6.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 38(2): 228-232, 2020 Apr 01.
Artículo en Chino | MEDLINE | ID: mdl-32314900

RESUMEN

Branching morphology is important to ensure that the organ can obtain the efficient functional morphology in a limited volume. The submandibular gland is a crucial model for studying the morphological processes of organ branches. Harvesting the submandibular gland from mouse embryo is also an essential research technique. In this paper, a modified method for obtaining the submandibular glands of mouse embryo was introduced, and the whole process of obtaining and establishing in vitro organ culture was briefly introduced to accurately simulate branch morphogenesis for vivo development and related research.


Asunto(s)
Embrión de Mamíferos , Glándula Submandibular , Animales , Ratones , Morfogénesis , Técnicas de Cultivo de Órganos
7.
Chem Commun (Camb) ; 56(10): 1597-1600, 2020 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-31935003

RESUMEN

Pyridines containing adjacent C[triple bond, length as m-dash]C bonds were utilized as ligand units and integrated into the skeleton of conjugated microporous polymers. The resultant Pd-CMP-1 was first applied as a highly efficient heterogeneous catalytic system for Pd-catalyzed allene hydrosilylation towards a wide range of allenes to produce branched allylsilanes with high regioselectivity. The ligand units of the polymer, along with the confinement effect of the porous structure, jointly regulated the regioselectivity. The parts-per-million (ppm) levels of Pd, coordinated with the recyclable heterogeneous ligand, show promise for industrial applications. This work opens a new front of using CMP as an intriguing platform for developing highly efficient catalysts to control the regioselectivities in allene hydrosilylation.

8.
Org Lett ; 20(24): 7748-7752, 2018 12 21.
Artículo en Inglés | MEDLINE | ID: mdl-30495967

RESUMEN

A porous organic polymer (POL-Xantphos) was synthesized and employed as a heterogeneous ligand for selective hydrosilylation of alkynes. It exhibits high selectivity and catalytic efficiency toward a broad range of alkynes. Owing to the confinement effect of the micropore structure, POL-Xantphos was far superior to the monomeric Xantphos ligands in controlling the selectivity. By performing hydrosilylation in a flow reactor system, separation and regeneration of the Ni/POL-Xantphos catalyst are easily achieved without any loss in selectivity or activity.

9.
Cancer Manag Res ; 9: 839-848, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29276406

RESUMEN

AIMS: To assess motion magnitude in different parts of the liver through surgical clips in postoperative patients with hepatocellular carcinoma and to examine the correlation between the clip and diaphragm motion. METHODS: Four-dimensional computed tomography images from 30 liver cancer patients under thermoplastic mask immobilization were selected for this study. Three to seven surgical clips were placed in the resection cavity of each patient. The liver volume on computed tomography image was divided into the right upper (RU), right middle (RM), right lower (RL), hilar, and left lobes. Agreement between the clip and diaphragm motion was assessed by calculating intraclass correlation coefficient, and Bland-Altman analysis (Diff). Furthermore, population-based and patient-specific margins for internal motion were evaluated. RESULTS: The clips located in the RU lobe showed the largest motion, (7.5±1.6) mm, which was significantly more than in the RM lobe (5.7±2.8 mm, p=0.019), RL lobe (4.8±3.3 mm, p=0.017), and hilar lobe (4.7±2.7 mm, p<0.001) in the cranial-caudal direction. The mean intraclass correlation coefficient values between the clip and diaphragm motion were 0.915, 0.735, 0.678, 0.670, and the mean Diff values between them were 0.1±0.8 mm, 2.3±1.4 mm, 3.1±2.0 mm, 2.4±1.5 mm, when clips were located in the RU lobe, RM lobe, RL lobe, and hilar lobe, respectively. The clip and diaphragm motions had high concordance when clips were located in the RU lobe. Internal margin can be reduced from 5 mm in the cranial-caudal direction based on patient population average and to 3 mm based on patient-specific margins. CONCLUSIONS: The motion magnitude of clips varied significantly depending on their location within the liver. The diaphragm was a more appropriate surrogate for tumor located in the RU lobe than for other lobes.

10.
Atherosclerosis ; 208(2): 427-32, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19732897

RESUMEN

BACKGROUND: Familial combined hyperlipidaemia (FCH) is the most common genetic dyslipidaemia associated with coronary artery disease. Single nucleotide polymorphisms (SNPs) and haplotypes in the APOA1/C3/A4/A5 gene cluster are associated with FCH in Caucasians and with elevated triglycerides (TG) in various ethnic groups. We examined these associations with FCH in Hong Kong Chinese. METHODS: Fifty-six Chinese FCH patients and 176 unrelated controls were studied. Thirteen SNPs in the APOA1/C3/A4/A5 cluster were genotyped. RESULTS: Four alleles in APOA5 were associated with FCH (P<0.001). The -1131T>C (rs662799) and -3A>G (rs651821) SNPs in APOA5 were in almost complete linkage disequilibrium (LD, r(2)=0.99), and their minor alleles were more frequent (P<0.001) in FCH than controls (0.60 vs. 0.24). The odds ratio (OR) for FCH was 6.2 (95% CI, 2.6-14.8) and 6.1 (2.6-14.6) per copy of -1131C and -3G, respectively, and 24.6 (8.4-72.0) and 24.4 (8.4-70.9) in -1131C and -3G homozygotes, respectively, as compared to wild-type homozygotes. The 1891T>C (rs2266788) SNP was in LD (r(2)=0.68) with -1131T>C and -3A>G, and the minor allele was more frequent in FCH than controls (0.42 vs. 0.19, P<0.001). The 553G>T (rs2075291) nonsynonymous variant was also associated with FCH (0.15 vs. 0.04, P=0.001) and, along with -3A>G (or -1131T>C) and 1891T>C, contributed to haplotypes predicting FCH. The two tightly linked SNPs, -1131T>C and -3A>G polymorphism were significantly associated with lipid traits in all subjects combined, with variant homozygous subjects having higher TG and LDL-C and lower HDL-C levels. CONCLUSIONS: Some common polymorphisms and haplotypes in APOA5 are closely associated with FCH in Hong Kong Chinese, and these differ from those found in Caucasians.


Asunto(s)
Apolipoproteína A-I/genética , Apolipoproteína C-III/genética , Apolipoproteínas A/genética , Hiperlipidemias/etnología , Hiperlipidemias/genética , Familia de Multigenes , Polimorfismo Genético , Adulto , Apolipoproteína A-V , Pueblo Asiatico , China , Femenino , Haplotipos , Hong Kong , Humanos , Desequilibrio de Ligamiento , Masculino , Persona de Mediana Edad , Fenotipo
11.
Med Princ Pract ; 14(5): 338-41, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16103700

RESUMEN

OBJECTIVE: To compare the antimicrobial resistance patterns of Acinetobacter baumannii isolates from Shanghai and Hong Kong. MATERIALS AND METHODS: A total of 212 A. baumannii strains of one isolate per patient were collected from Shanghai and Hong Kong from August 2002 to August 2003 that were tested against 15 commonly used antimicrobial agents by the agar dilution method according to the NCCLS guidelines. RESULTS: Most beta-lactams showed no significant increase in activity after adding beta-lactamase inhibitors. The resistance rates of the isolates against ticarcillin-clavulanate, piperacillin-tazobactam and ampicillin-sulbactam were for Shanghai 74.9, 70.9, 69.1% and Hong Kong 24.3, 18.9, 13.5%, respectively. Only cefoperazone-sulbactam showed a significant increase in activity against both Shanghai and Hong Kong strains, as the resistance rates dropped from 93.7 to 8.6% and 83.8 to 5.4%, respectively. The resistance rates of ceftazidime, cefepime, and gentamicin against Shanghai strains were 69.7, 72.0, 73.7% and Hong Kong strains 69.7, 29.7, 18.9%, respectively. About 65% of Shanghai strains were found to be amikacin-resistant, however, all Hong Kong strains were sensitive. Fluoroquinolones including ciprofloxacin and levofloxacin had resistance rates over 60% against Shanghai strains, but only 13.5% against Hong Kong strains. Shanghai strains had imipenem and meropenem resistance rate of 6.3%. Though 10.8% Hong Kong strains were resistant to meropenem, only 2.7% of them were resistant to imipenem. CONCLUSION: A. baumannii isolated from Shanghai were more resistant to all drugs except meropenem than Hong Kong isolates. The results indicate a need for measures to control the abuse of antibiotic usage in order to prevent the emergence of more multidrug-resistant isolates in both cities.


Asunto(s)
Acinetobacter baumannii/efectos de los fármacos , Antibacterianos/farmacología , Infección Hospitalaria/microbiología , Farmacorresistencia Bacteriana Múltiple , Resistencia betalactámica , Inhibidores de beta-Lactamasas , beta-Lactamas/farmacología , Acinetobacter baumannii/enzimología , Acinetobacter baumannii/aislamiento & purificación , Amicacina/farmacología , Ampicilina/farmacología , China , Ácido Clavulánico/farmacología , Infección Hospitalaria/tratamiento farmacológico , Inhibidores Enzimáticos/farmacología , Fluoroquinolonas/farmacología , Hong Kong , Humanos , Imipenem/farmacología , Meropenem , Pruebas de Sensibilidad Microbiana , Ácido Penicilánico/análogos & derivados , Ácido Penicilánico/farmacología , Piperacilina/farmacología , Sulbactam/farmacología , Tazobactam , Tienamicinas/farmacología , Ticarcilina/farmacología
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