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Gold-catalyzed cyclization of 2-alkynyl-N-propargylanilines provides a step-economic method for the construction of three-dimensional indolines. In this article, the M06 functional of density functional theory was employed to gain deeper insights into the reaction mechanism and the associated intriguing experimental observations. The reaction was found to first undergo Au(I)-induced cyclization to form an indole intermediate, 1,3-propargyl migration, and substitution with the substrate 2-alkynyl-N-propargylaniline (R1) to generate the intermediate product P1, an allene species. Subsequently, Au(I)-catalyzed conversion of P1 into the final product P2, an indoline compound, occurs first through direct cyclization rather than via the previously proposed four-membered carbocycle intermediate. Thereafter, water-assisted oxygen heterocycle formation and proton transfer generate the final product. The calculated activation free energies indicate that P1 formation is 5.9 times slower than P2 formation, in accordance with the fact that P1 formation is rate-limiting. Futhermore, the intriguing experimental phenomenon that P2 can be accessed only after almost all the substrate R1 converts to P1 although P1 formation is rate-limiting was rationalized by employing an energetic span model. We found the initial facile cyclization to form a highly stable indole intermediate in the formation of P1 is the key to the intriguing experimental phenomenon. [ABSTRACT FROM AUTHOR]

The function of Smad3, a downstream signaling protein of the transforming growth factor β (TGFβ) pathway, in ovarian follicle development remains to be elucidated. The effects of Smad3 on ovarian granulosa cells (GCs) in rat were studied. Female rats (21 days of age Sprague-Dawley) received i.p. injections of pregnant mare serum gonadotropin, and GCs were harvested for primary culture 48 h later. These cells were engineered to overexpress or knockdown Smad3, which were validated by immunohistochemistry and western blot. The expression of proliferating cell nuclear antigen (PCNA), cyclin D2, TGFβ receptor II (TGFβRII), protein kinase A (PKA), and FSH receptor (FSHR) was also detected by western blotting. Cell cycle and apoptosis of GCs were assayed by flow cytometry. The level of estrogen secreted by GCs was detected by ELISA. Smad3 overexpression promoted estrogen production and proliferation while inhibiting apoptosis of GCs. Reduction in Smad3 by RNAi resulted in reduced estrogen production and proliferation and increased apoptosis of GCs. Manipulation of Smad3 expression also resulted in changes in FSHR and PKA expression, suggesting that the effects of Smad3 on follicle development are related to FSHR-mediated cAMP signaling. [ABSTRACT FROM AUTHOR]

As large amount of vasoactive intestinal peptide (VIP) receptors are expressed in various tumors and VIP-related diseases, radiolabeled VIP provides a potential PET imaging agent for VIP receptor. However, structural modification of VIP is required before being radiolabeled and used for VIP receptor imaging due to its poor in vivo stability. As a VIP analogue, [R8,15,21, L17]-VIP exhibited improved stability and receptor specificity in preliminary studies. In this study, F-18 labeled [R8,15,21, L17]-VIP was produced with the radiochemical yield being as high as 33.6% ±3% (decay-for-corrected, n = 5) achieved within 100 min, a specific activity of 255 GBq/μmol, and a radiochemical purity as high as 99% as characterized by radioactive HPLC, TLC, and SDS-Page radioautography. A biodistribution study in normal mice also demonstrated fast elimination of F-18 labeled [R8,15,21, L17]-VIP in the blood, liver, and gastrointestinal tracts. A further micro-PET imaging study in C26 colon carcinoma bearing mice confirmed the high tumor specificity, with the tumor/muscle radioactivity uptake ratio being as high as 3.03 at 60 min following injection, and no apparent radioactivity concentration in the intestinal tracts. In addition, blocking experiment and Western Blot test further confirmed its potential in PET imaging of VIP receptor-positive tumor. [ABSTRACT FROM AUTHOR]

Density functional theory (DFT) calculations have beencarriedout to study the detailed mechanism of CO inserting into the N–Hbond rather than the common Fe–N bond of the iron(II) amidocomplex (dmpe)2Fe(H)(NH2) (dmpe = 1,2-bis(dimethylphosphino)ethane).Three mechanisms proposed in previous literature have been computationallyexamined, and all of them are found to involve high barriers and thuscannot explain the observed N–H insertion product. Alternatively,on the basis of the calculated results, a novel reactant-assisted(self-promoted) mechanism is presented, which provides the most efficientaccess to the insertion reaction via the assistance of a second reactantmolecule. In detail, the reaction starts from direct attack of COat the amide nitrogen atom of (dmpe)2Fe(H)(NH2), followed by a second reactant-assisted H abstraction/donationprocesses to afford the trans product of CO inserting into the N–Hbond of the amido complex. The present theoretical results providea new insight into the mechanism of the unusual insertion reactionand rationalize the experimental findings well. [ABSTRACT FROM AUTHOR]

The chemical modification of oligomers such as DNA, PNA, MORF, LNA to attach radionuclides for nuclear imaging and radiotherapy applications has become a field rich in innovation as older methods are improved and new methods are introduced. This review intends to provide a brief overview of several chelators currently in use for the labeling of oligomers with metallic radionuclides such as 99mTc, 111In and 188Re. While DNA and its analogs have been radiolabeled with important radionuclides of nonmetals such as 32P, 35S, 14C, 18F and 125I, the labeling methods for these isotopes involve covalent chemistry that is quite distinct from the coordinate-covalent chelation chemistry described herein. In this review, we provide a summary of the several chelators that have been covalently conjugated to oligomers for the purpose of radiolabeling with metallic radionuclides by chelation and including details on the conjugation, the choice of radionuclides and labeling methods. [ABSTRACT FROM AUTHOR]

Dipotassio-9-germafluorenyl dianion (3b) was synthesized by reduction of 9,9-dichloro-9germafluorene (4b) with sodium/potassium alloy in tetrahydrofuran. The X-ray crystal structure of 3b, like that for the analogous silicon compound 3a, shows C-C bond length equalization in the five-membered metallole rings and C-C bond length alternation in the six-membered benzenoid rings, indicating aromatic delocalization of electrons into the germole ring of 3b. Calculated nucleus independent chemical shift (NICS) values indicate that the five-membered ring is more aromatic than the six-membered rings in 3a and 3b. Derivatization of 3b with Me[sub 3]SiCl gave 9,9-bis(trimethylsilyl)-9-germafluorene (5). Controlled oxidation of 3b yielded dipotassio-9,9'-digerma-9,9'-bifluorenyl dianion (6). Reaction of 6 with MeOH yielded 9,9'-digerma9,9'-bifluorene (7). The X-ray structure of 6 indicates C-C bond length alternation in the five-membered rings. Thus dianion 6, like its silicon analogue 8, has the negative charges localized at metal atoms and no aromatic character. Dipotassio-9,9'-bifluorenyl dianion (9), the carbon analogue of 6, exhibits aromaticity with its X-ray crystal structure showing the C-C bond length equalization in both the five- and six-membered rings. Derivatization of 9 with Mel gave 9,9'-dimethyl-9,9'-bifluorene (10). The structure of 10 shows that the two fluorenyl rings are cis to each other with a torsional angle of 59° and a long C-C single bond (1.60 Å) connecting them. [ABSTRACT FROM AUTHOR]

We report the synthesis of a novel, highly fluorescent pentacoordinate silicon compound which is apparently the first example of a vinylogous -diketonate complex. The compound was generated by slow, solid-state oxidation of a methoxysilane derivative of tetraphenylcyclopentadiene. [ABSTRACT FROM AUTHOR]

Objective: To examine the factors influencing hospital discharge readiness among Chinese patients who have undergone enterostomy., Methods: In this descriptive, cross-sectional study, researchers recruited patients with colorectal cancer who underwent enterostomy at a tertiary hospital in Guangdong Province, China, via convenience sampling between January 2021 and January 2023. Participants completed the Readiness for Hospital Discharge Scale, Ostomy Self-care Ability Scale, and Stoma-Quality of Life-Chinese Questionnaire (Chinese version) at the time of hospital discharge. Univariate, correlation, and multiple linear regression analyses were performed to explore the impact of self-care ability, quality of life, and other clinicodemographic characteristics on patients' readiness for hospital discharge., Results: Of the 200 questionnaires distributed, 177 (88.5%) were completed and included in the final analysis. The median scores for the factors considered in this study were as follows: Readiness for Hospital Discharge Scale was 148.00 (interquartile range [IQR], 117.50, 164.00), self-care intention of the Ostomy Self-care Ability Scale was 36.00 (IQR, 34.00, 40.00), self-care knowledge of the Ostomy Self-care Ability Scale was 17.00 (IQR, 15.00, 19.00), self-care skill of the Ostomy Self-care Ability Scale was 5.00 (IQR, 3.00, 6.00), and the total score for quality of life was 60.00 (IQR, 49.00, 69.00). Multiple linear regression analysis identified several key factors explaining 48.2% of the variance in global readiness for hospital discharge: global quality of life (β = .347, P < .001), self-care knowledge (β = .259, P < .001), leakage during hospitalization (β = -0.241, P < .001), monthly family income (β = .148, P = .008), stoma siting before surgery (β = .130, P = .020), and self-care intention (β = .127, P = .035)., Conclusions: The readiness for hospital discharge among patients undergoing enterostomy in this study was high. Factors such as quality of life, self-care knowledge, leakage during hospitalization, monthly family income, stoma siting before surgery, and self-care intention after undergoing enterostomy influenced the patients' readiness for hospital discharge. Therefore, future studies should focus on developing interventions to enhance patients' readiness for hospital discharge., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Objective: To identify variables that may predict psychological distress in patients with an enterostomy., Methods: Investigators recruited 77 patients with a stoma from a stoma clinic according to the inclusion criteria. Patients' psychological distress was assessed with the Distress Thermometer (DT) tool, and their personality type was determined by the Eysenck Personality Questionnaire. Researchers also collected demographic and disease-related data. Predictive values were estimated using multiple regression analyses., Results: The mean DT score of all patients was 5.94 (SD, 1.81), and approximately 85.7% consistently suffered from psychological distress. Being unmarried and having peristomal complications were associated with higher psychological distress, whereas having a monthly income 5,000 ¥ or more was associated with lower levels of distress. Moreover, patients with a melancholic personality type tended to have higher DT scores, which could act as a strong independent predictor for psychological distress., Conclusions: The majority of patients with a stoma endured moderate to severe psychological distress during follow-up care. Exploring the related factors that predict the levels of psychological distress could enable clinicians to identify at-risk patients as early as possible and thus provide optimal care for improving patients' quality of life., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

Objective: To assess the efficacy of Sanyrene liquid dressing (Urgo Medical) in preventing radiation dermatitis (RD) among patients with cancer after radiotherapy., Data Sources: The authors searched the China National Knowledge Infrastructure, SinoMed, WanFang Data, PubMed, Web of Science, EMBASE, and the Cochrane Library databases for articles published from inception to January 2021., Study Selection: The preliminary search identified 146 studies. After removing duplicates, applying exclusion criteria, and screening titles and abstracts, 19 studies met the inclusion criteria., Data Extraction: A standardized form was constructed to extract data from eligible studies. Two reviewers independently screened the literature, extracted data, and assessed the risk of bias of the included studies., Data Synthesis: The authors identified a total of 19 studies involving 1,508 patients that assessed the effectiveness of Sanyrene liquid dressing in preventing RD in patients with cancer after radiotherapy. The findings suggested that Sanyrene decreases the total incidence of RD (odds ratio [OR], 5.00; 95% CI, 2.77-9.03; P < .00001), as well as the incidence of RD grade 2 (OR, 0.55; 95% CI, 0.36-0.85; P = .007), grade 3 (OR, 0.22; 95% CI, 0.09-0.57; P = .002), and grade 4 (OR, 0.32; 95% CI, 0.13-0.78; P = .01). In addition, in comparison with controls, Sanyrene liquid dressing improves the cure rate (OR, 8.18; 95% CI, 4.03-16.60; P < .00001) and delays the occurrence of RD (mean difference, 3.69; 95% CI, 3.03-4.36; P < .00001)., Conclusions: Sanyrene liquid dressing can decrease both the total incidence of RD and the incidence of RD above grade 2. It also improves the cure rate and delays the occurrence of RD. Thus, Sanyrene may be a superior option for preventing RD after radiotherapy. However, the findings were assessed as moderate- to low-quality evidence and more high-quality trials are needed to support this result., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)