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1.
World J Gastrointest Oncol ; 16(4): 1192-1203, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38660657

RESUMO

BACKGROUND: Indentifying predictive factors for postoperative recurrence of hepatocellular carcinoma (HCC) has great significance for patient prognosis. AIM: To explore the value of gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA) enhanced magnetic resonance imaging (MRI) combined with clinical features in predicting early recurrence of HCC after resection. METHODS: A total of 161 patients with pathologically confirmed HCC were enrolled. The patients were divided into early recurrence and non-early recurrence group based on the follow-up results. The clinical, laboratory, pathological results and Gd-EOB-DTPA enhanced MRI imaging features were analyzed. RESULTS: Of 161 patients, 73 had early recurrence and 88 were had non-early recurrence. Univariate analysis showed that patient age, gender, serum alpha-fetoprotein level, the Barcelona Clinic Liver Cancer stage, China liver cancer (CNLC) stage, microvascular invasion (MVI), pathological satellite focus, tumor size, tumor number, tumor boundary, tumor capsule, intratumoral necrosis, portal vein tumor thrombus, large vessel invasion, nonperipheral washout, peritumoral enhancement, hepatobiliary phase (HBP)/tumor signal intensity (SI)/peritumoral SI, HBP peritumoral low signal and peritumoral delay enhancement were significantly associated with early recurrence of HCC after operation. Multivariate logistic regression analysis showed that patient age, MVI, CNLC stage, tumor boundary and large vessel invasion were independent predictive factors. External data validation indicated that the area under the curve of the combined predictors was 0.861, suggesting that multivariate logistic regression was a reasonable predictive model for early recurrence of HCC. CONCLUSION: Gd-EOB-DTPA enhanced MRI combined with clinical features would help predicting the early recurrence of HCC after operation.

2.
Transl Androl Urol ; 11(4): 480-494, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35558269

RESUMO

Background: Prostatic arterial embolization (PAE) is an effective minimally invasive treatment for lower urinary tract obstruction and hematuria in patients with benign prostatic hyperplasia (BPH). This study was aim to evaluate the safety and short-term efficacy of drug epirubicin-loaded beads transarterial prostatic arterial chemoembolization (DEB-PACE) for the treatment of advanced prostate cancer (PC) with lower urinary tract obstruction or hematuria. Methods: A total of 8 patients with advanced PC undergoing DEB-PACE from August 2020 to February 2022 were retrospectively enrolled. The patients were followed up at 1 week, 1, 3, 6 and 12 months after DEB-PACE. The origin of prostatic arteries, technical success, clinical success rate, duration of the indwelling urinary catheter, International Prostate Symptom Score (IPSS), QoL score (quality of life), prostate volume (PV), prostate-specific antigen (PSA) level and complications were recorded. The short-term efficacy (changes in IPSS, PV and QoL value from baseline to 3 months) were analysed. Results: There were 17 prostatic arteries in 8 patients, which mainly originated from internal pudendal artery (11/17, 64.7%), the technical success rate is 100%. After treatment, the symptoms of lower urethral obstruction in 8 patients were significantly improved that PSA, PV, IPSS and QoL level were significantly reduced. The catheter was successfully removed within 1 week on average, and 2 patients with hematuria disappeared within 5 days. The clinical success rate is 100%. At 1 month postoperatively, mean PV reduction was 30.28±6.963 cm3 (P=0.0457), mean IPSS reduction was 21.13±2.887 points (P=0.0042), mean QoL reduction was 3.75±0.366 points (P=0.006). At 3 months postoperatively, mean PV reduction was 46.14±8.906 cm3 (P=0.0112), mean IPSS reduction was 24.5±2.398 points (P=0.0003), mean QoL reduction was 4.25±0.25 points (P=0.0003). There were no serious complications occurred in all patients. Conclusions: DEB-PACE is a promising treatment for advanced PC with lower urinary tract obstruction or hematuria. However, the efficacy and safety of DEB-PACE for advanced PC is needed to validated by prospective large sample randomized controlled study.

3.
Int J Clin Exp Med ; 8(10): 18455-61, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26770452

RESUMO

BACKGROUND: Quantification of the association between the consumption of vegetables and risk of age-related cataract is still conflicting. We therefore conducted a meta-analysis to summarize the evidence from epidemiological studies of vegetables consumption with the risk of age-related cataract. METHODS: Pertinent studies were identified by searching of PubMed and Web of Science. The random effect model was used to combine the results. Meta-regression and subgroups analyses were used to explore potential sources of between-study heterogeneity. Publication bias was estimated using Egger's regression asymmetry test. RESULTS: Finally, 9 articles involving 6,464 cataract cases and 112,447 participants were included in this meta-analysis. Pooled results suggested that highest vegetables consumption level compared with lowest level was inverse with the risk of age-related cataract [summary relative risk (RR) = 0.723, 95% CI = 0.594-0.879, I(2) = 72.8%]. The associations were also significant in America [summary RR = 0.872, 95% CI = 0.791-0.960] and Europe [summary RR = 0.507, 95% CI = 0.416-0.619], but not in the other population. No publication bias was found. CONCLUSIONS: Higher vegetables consumption might be inversely associated with risk of cataract.

4.
Org Lett ; 6(26): 4937-9, 2004 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-15606104

RESUMO

[reaction: see text] In this Letter, we describe a general method for preparing the dianions of cyclopropene carboxylic acids, and we show that their subsequent reactions with electrophiles provide a general means for selectively introducing diverse types of functional groups. This provides a general method for the synthesis of chiral 1,2-disubstituted cyclopropenes, and opens new avenues for the enantioselective preparation of cyclopropenes.


Assuntos
Ácidos Carboxílicos/síntese química , Ciclopropanos/síntese química , Ânions/química , Ácidos Carboxílicos/química , Ciclopropanos/química , Conformação Molecular , Estereoisomerismo
5.
J Org Chem ; 69(21): 7317-28, 2004 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-15471486

RESUMO

A theoretical study specifically addresses the question of whether nucleophilic addition to the carbonyl groups of acid chlorides, esters, and anhydrides involves an addition-elimination pathway or proceeds by a concerted S(N)2-like mechanism in the absence of the generally assumed tetrahedral intermediate. Density functional calculations [B3LYP/6-31+G(d,p)] establish that chloride ion exchange reactions with both formyl and acetyl chloride proceed by a pi attack on the C=O bond. No discernible tetrahedral intermediate typical of an addition-elimination pathway was found in either case. While a tetrahedral intermediate does exist for the addition of fluoride ion to (Cl)(2)C=O, halide exchange of LiCl with both ClFC=O and (Cl)(2)C=O also proceeds by a concerted S(N)2-like pathway. The formation of a tetrahedral intermediate from the addition of methanol to acetyl chloride is slightly exothermic (4.4 kcal/mol). The ion-dipole complex of methanol weakly bonded to the carbonyl carbon of protonated acetyl chloride is stabilized by 13.8 kcal/mol but does not collapse to a tetrahedral intermediate. When four CH(3)OH molecules are H-bonded to protonated acetyl chloride, a tetrahedral intermediate is not completely formed and this solvated complex more closely resembles the precursor to an S(N)1-type ionization of Cl(-). With six H-bonding methanol molecules, a methanol adds to the carbonyl carbon and a proton relay occurs with formation of a tetrahedral-like structure that immediately loses chloride ion in an S(N)1-like solvolysis. These results corroborate earlier suggestions (Bentley et al. J. Org. Chem. 1996, 61, 7927) that the methanolysis of acetyl chloride does not proceed through the generally assumed addition-elimination pathway with a discrete tetrahedral intermediate but is consistent with ionization of Cl(-). The reaction of methoxide ion with methyl acetate proceeds via a multiple-well energy surface and involves the intermediacy of an asymmetrical species with differing C-OMe bond lengths. Models of synthetic applications of acyl transfer reactions involving anhydrides that form N-acyloxazolidinones also proceed by a concerted S(N)2-type pathway even with the carboxylate leaving group. Concerted transition states were observed for the reactions of each enantiomer of a 1,3-diphenylcycloprop-2-ene carboxylic anhydride by S-3-lithio-4-phenyloxazolidinone. Despite close structural similarities between the diastereomeric transition states, the relative energies correlated closely with the experimental results.


Assuntos
Carbono/química , Modelos Químicos , Compostos Orgânicos/síntese química , Simulação por Computador , Ciclopropanos/química , Cinética , Modelos Moleculares , Estrutura Molecular , Oxazolidinonas/síntese química
6.
J Am Chem Soc ; 126(14): 4490-1, 2004 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-15070346

RESUMO

A new type of parallel kinetic resolution (PKR) is reported in which quasienantiomers with very similar reactivities give products whose chromatographic properties diverge upon the addition of fluoride. This concept of a reactivity/affinity switch is applied to the PKR of cyclopropene carboxylic acids with all-carbon quaternary centers. This is the first application of alpha-amino acid quasienantiomers in PKR, and it is a complementary approach for acyltransfer systems where the asymmetry is induced by the nucleophile rather than the leaving group. Excellent diastereoselectivities (ranging from 90:10 to 99.5:5) and good yields were obtained for both quasienantiomeric products, and the reactions can be run on significant scale because the separation is trivial. High-level DFT calculations (B3LYP functional with the 6-31+G(d,p) basis set) provided transition-state structures with relative energies that are in accord with the experimental observations.


Assuntos
Aminoácidos/química , Ácidos Carboxílicos/química , Ciclopropanos/química , Aminoácidos/síntese química , Ácidos Carboxílicos/síntese química , Ciclopropanos/síntese química , Cinética , Estereoisomerismo , Termodinâmica
7.
J Am Chem Soc ; 124(48): 14322-3, 2002 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-12452703

RESUMO

A Cu-catalyzed method for the addition of Grignard reagents to 1-alkyl-3-hydroxymethylcyclopropenes and their MOM ethers is described. The face of addition is syn relative to the hydroxymethyl and alkoxymethyl groups. Excellent diastereoselectivity is observed for a range of alkyl, alkenyl, and alkynylmagnesium halides. The addition reactions create chiral all-carbon quaternary centers, and the cyclopropylmetals that are generated can be reacted with electrophiles to produce highly functionalized cyclopropanes.

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