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1.
Ann Surg Oncol ; 31(2): 1243-1251, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37947973

RESUMO

BACKGROUND: Limited anatomic resections (LARs), such as segmentectomies, performed using a fully laparoscopic approach, have gained popularity for liver malignancies. However, the oncologic efficacy of laparoscopic LARs (Lap-LARs) needs further investigation. This cohort study evaluated the oncologic outcomes of Lap-LAR for hepatocellular carcinoma (HCC) and colorectal liver metastasis (CRLM). METHODS: At a Japanese referral center, 112 patients underwent Lap-LAR using the Glissonean approach and indocyanine green (ICG) fluorescence navigation. Recurrence-free survival (RFS), overall survival (OS), time to interventional failure (TIF), and time to surgical failure (TSF) were assessed. RESULTS: Among the 112 patients (median age, 74 years [range, 66-80 years]; 80 men [71.4 %]), Lap-LAR showed promising results. The median operative time was 348 min (range, 280-460 min), and the median blood loss was 190 mL (range, 95.5-452.0 mL). The median error between the estimated and actual liver volumes was 2 % (1.2-4.8 %). Complications greater than Clavien-Dindo 3a were observed in 11.6 % of the patients. The 5-year RFS, OS, and TIF rates for HCC were 45.1 % ± 7.9 %, 73.1 % ± 6.7 %, and 74.2 % ± 6 .6 %, respectively. The 5-year RFS, OS, and TSF rates for CRLM were 36.8 % ± 8.7 %, 60.1 % ± 13.3 %, and 63.6 % ± 10.4 %, respectively. CONCLUSIONS: Lap-LAR showed favorable oncologic outcomes for HCC and CRLM. Its precise technique makes it a promising therapeutic option for liver malignancies. Further comparisons with conventional approaches are warranted.


Assuntos
Carcinoma Hepatocelular , Laparoscopia , Neoplasias Hepáticas , Masculino , Humanos , Idoso , Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/secundário , Estudos de Coortes , Hepatectomia/métodos , Laparoscopia/métodos , Estudos Retrospectivos
2.
Org Biomol Chem ; 21(38): 7681-7690, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37725053

RESUMO

Significant advancements have been made in the synthesis of overlooked aza-S(IV) motifs. The accessibility of sulfinamidines and sulfinimidate esters has greatly improved through the recent development of efficient and complementary synthetic strategies. Intriguingly, new discoveries have emerged regarding the reactivity of these substances, highlighting the electrophilic nature of sulfinimidate esters and the nucleophilic character of sulfinamidines. Moreover, sulfinamidines have been found to be prone to oxidation, leading to the formation of important aza-S(VI) derivatives. In this review, our aim is to present an almost comprehensive overview of the most relevant achievements in the preparation and structural characterization of these overlooked compounds.

3.
Int J Mol Sci ; 24(3)2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36769379

RESUMO

Although the imbalance of circulating levels of Thyroid Hormones (THs) affects female fertility in vertebrates, its involvement in the promotion of Premature Ovarian Aging (POA) is debated. Therefore, altered synthesis of THs in both thyroid and ovary can be a trait of POA. We investigated the relationship between abnormal TH signaling, dysthyroidism, and POA in evolutionary distant vertebrates: from zebrafish to humans. Ovarian T3 signaling/metabolism was evaluated by measuring T3 levels, T3 responsive transcript, and protein levels along with transcripts governing T3 availability (deiodinases) and signaling (TH receptors) in distinct models of POA depending on genetic background and environmental exposures (e.g., diets, pesticides). Expression levels of well-known (Amh, Gdf9, and Inhibins) and novel (miR143/145 and Gas5) biomarkers of POA were assessed. Ovarian dysthyroidism was slightly influenced by genetics since very few differences were found between C57BL/6J and FVB/NJ females. However, diets exacerbated it in a strain-dependent manner. Similar findings were observed in zebrafish and mouse models of POA induced by developmental and long-life exposure to low-dose chlorpyrifos (CPF). Lastly, the T3 decrease in follicular fluids from women affected by diminished ovarian reserve, as well as of the transcripts modulating T3 signaling/availability in the cumulus cells, confirmed ovarian dysthyroidism as a common and evolutionary conserved trait of POA.


Assuntos
MicroRNAs , Ovário , Camundongos , Animais , Feminino , Humanos , Ovário/metabolismo , Peixe-Zebra/metabolismo , Camundongos Endogâmicos C57BL , Hormônios Tireóideos/metabolismo , Envelhecimento , MicroRNAs/metabolismo
4.
Org Biomol Chem ; 20(23): 4669-4680, 2022 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-35587647

RESUMO

In recent years, fluoroiodomethane (CH2FI) has emerged as an easy-to-handle, non-ozone depleting agent and readily available platform for monofluoromethylation strategies. Recent applications in nucleophilic substitutions, lithiation reactions, transition-metal catalyzed transformations, radical processes, and 18F-radiolabelling chemistry showcase the potential of this reagent for the preparation of organofluorine compounds. In this minireview, we provide an update to the field covering the recent relevant literature on the use of CH2FI.


Assuntos
Elementos de Transição , Indicadores e Reagentes , Elementos de Transição/química
5.
Molecules ; 27(9)2022 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-35566200

RESUMO

In this work it is demonstrated that enantiomerically enriched N-alkyl 2-oxazolinylazetidines undergo exclusive α-lithiation, and that the resulting lithiated intermediate is chemically stable but configurationally labile under the given experimental conditions that afford enantioenriched N-alkyl-2,2-disubstituted azetidines. Although this study reveals the configurational instability of the diastereomeric lithiated azetidines, it points out an interesting stereoconvergence of such lithiated intermediates towards the thermodynamically stable species, making the overall process highly stereoselective (er > 95:5, dr > 85:15) after trapping with electrophiles. This peculiar behavior has been rationalized by considering the dynamics at the azetidine nitrogen atom, the inversion at the C-Li center supported by in situ FT-IR experiments, and DFT calculations that suggested the presence of η3-coordinated species for diastereomeric lithiated azetidines. The described situation contrasted with the demonstrated stability of the smaller lithiated aziridine analogue. The capability of oxazolinylazetidines to undergo different reaction patterns with organolithium bases supports the model termed "dynamic control of reactivity" of relevance in organolithium chemistry. It has been demonstrated that only 2,2-substituted oxazolinylazetidines with suitable stereochemical requirements could undergo C=N addition of organolithiums in non-coordinating solvents, leading to useful precursors of chiral (er > 95:5) ketoazetidines.


Assuntos
Azetidinas , Lítio , Nitrogênio , Espectroscopia de Infravermelho com Transformada de Fourier , Estereoisomerismo
6.
J Org Chem ; 86(20): 13943-13954, 2021 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-34291947

RESUMO

The generation and functionalization, under continuous flow conditions, of two different lithiated four-membered aza-heterocycles is reported. N-Boc-3-iodoazetidine acts as a common synthetic platform for the genesis of C3-lithiated azetidine and C2-lithiated azetine depending on the lithiation agent. Flow technology enables easy handling of such lithiated intermediates at much higher temperatures compared to batch processing. Flow technology combined with cyclopentylmethyl ether as an environmentally responsible solvent allows us to address sustainability concerns.


Assuntos
Azetidinas , Azetinas
7.
Org Biomol Chem ; 19(9): 1945-1949, 2021 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-33595577

RESUMO

The reaction between configurably stable α-lithiated oxiranes and 3-substituted cyclobutanones allows obtaining enantiomerically enriched cyclobutanols (er > 98 : 2). These adducts, subjected to base-mediated Payne rearrangement, lead to the synthesis of a new class of oxaspirohexanes, useful precursors of 2,4-disubstituted cyclopentanones.

8.
Int J Mol Sci ; 22(17)2021 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-34502288

RESUMO

Thyroid hormone levels are usually genetically determined. Thyrocytes produce a unique set of enzymes that are dedicated to thyroid hormone synthesis. While thyroid transcriptional regulation is well-characterized, post-transcriptional mechanisms have been less investigated. Here, we describe the involvement of ZFP36L2, a protein that stimulates degradation of target mRNAs, in thyroid development and function, by in vivo and in vitro gene targeting in thyrocytes. Thyroid-specific Zfp36l2-/- females were hypothyroid, with reduced levels of circulating free Thyroxine (cfT4) and Triiodothyronine (cfT3). Their hypothyroidism was due to dyshormonogenesis, already evident one week after weaning, while thyroid development appeared normal. We observed decreases in several thyroid-specific transcripts and proteins, such as Nis and its transcriptional regulators (Pax8 and Nkx2.1), and increased apoptosis in Zfp36l2-/- thyroids. Nis, Pax8, and Nkx2.1 mRNAs were also reduced in Zfp36l2 knock-out thyrocytes in vitro (L2KO), in which we confirmed the increased apoptosis. Finally, in L2KO cells, we showed an altered response to TSH stimulation regarding both thyroid-specific gene expression and cell proliferation and survival. This result was supported by increases in P21/WAF1 and p-P38MAPK levels. Mechanistically, we confirmed Notch1 as a target of ZFP36L2 in the thyroid since its levels were increased in both in vitro and in vivo models. In both models, the levels of Id4 mRNA, a potential inhibitor of Pax8 activity, were increased. Overall, the data indicate that the regulation of mRNA stability by ZFP36L2 is a mechanism that controls the function and survival of thyrocytes.


Assuntos
Glândula Tireoide/fisiologia , Tristetraprolina/fisiologia , Animais , Apoptose/fisiologia , Linhagem Celular , Sobrevivência Celular , Feminino , Deleção de Genes , Regulação da Expressão Gênica , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Fator de Transcrição PAX8/genética , Ratos , Receptor Notch1/metabolismo , Glândula Tireoide/citologia , Glândula Tireoide/efeitos dos fármacos , Tireotropina/farmacologia , Tristetraprolina/genética
9.
Chemistry ; 26(1): 19-32, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31498924

RESUMO

In the field of organic synthesis, the advent of flow chemistry and flow microreactor technology represented a tremendous novelty in the way of thinking and performing chemical reactions, opening the doors to poorly explored or even impossible transformations using batch methods. In this Concept article, we would like to highlight the impact of flow chemistry for exploiting highly reactive organometallic reagents, and how, alongside the well-known advantages concerning safety, scalability, and productivity, flow chemistry makes possible processes that are impossible to control by using the traditional batch approach.

10.
Molecules ; 25(14)2020 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-32708643

RESUMO

Indole derivatives are among the most useful and interesting heterocycles employed in drug discovery and medicinal chemistry. In addition, flow chemistry and flow technology are changing the synthetic paradigm in the field of modern synthesis. In this review, the role of flow technology in the preparation of indole derivatives is showcased. Selected examples have been described with the aim to provide readers with an overview on the tactics and technologies used for targeting indole scaffolds.


Assuntos
Química Farmacêutica/tendências , Compostos Heterocíclicos/síntese química , Indóis/síntese química , Compostos Heterocíclicos/química , Humanos , Indóis/química
11.
Angew Chem Int Ed Engl ; 59(27): 10924-10928, 2020 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-32239778

RESUMO

The external quenching method based on flow microreactors allows the generation and use of short-lived fluoro-substituted methyllithium reagents, such as fluoromethyllithium, fluoroiodomethyllithium, and fluoroiodostannylmethyllithium. Highly chemoselective reactions have been developed, opening new opportunities in the synthesis of fluorinated molecules using fluorinated organometallics.

13.
Angew Chem Int Ed Engl ; 58(40): 14303-14310, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31390133

RESUMO

Sulfonimidamides are intriguing new motifs for medicinal and agrochemistry, and provide attractive bioisosteres for sulfonamides. However, there remain few operationally simple methods for their preparation. Here, the synthesis of NH-sulfonimidamides is achieved directly from sulfenamides, themselves readily formed in one step from amines and disulfides. A highly chemoselective and one-pot NH and O transfer is developed, mediated by PhIO in iPrOH, using ammonium carbamate as the NH source, and in the presence of 1 equivalent of acetic acid. A wide range of functional groups are tolerated under the developed reaction conditions, which also enables the functionalization of the antidepressants desipramine and fluoxetine and the preparation of an aza analogue of the drug probenecid. The reaction is shown to proceed via different and concurrent mechanistic pathways, including the formation of novel S≡N sulfanenitrile species as intermediates. Several alkoxy-amino-λ6 -sulfanenitriles are prepared with different alcohols, and shown to be alkylating agents to a range of nucleophiles.


Assuntos
Álcoois/química , Aminas/química , Nitrilas/química , Sulfamerazina/química , Sulfonamidas/síntese química , Estrutura Molecular , Sulfonamidas/química
14.
J Am Chem Soc ; 139(39): 13648-13651, 2017 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-28892363

RESUMO

The first direct and straightforward nucleophilic fluoromethylation of organic compounds is reported. The tactic employs a "fleeting" lithium fluorocarbenoid (LiCH2F) generated from commercially available fluoroiodomethane. Precise reaction conditions were developed for the generation and synthetic exploitation of such a labile species. The versatility of the strategy is showcased in ca. 50 examples involving a plethora of electrophiles. Highly valuable chemicals such as fluoroalcohols, fluoroamines, and fluoromethylated oxygenated heterocycles could be prepared in very good yields through a single synthetic operation. The scalability of the reaction and its application to complex molecular architectures (e.g., steroids) are documented.

15.
Org Lett ; 26(15): 3032-3036, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38547907

RESUMO

The oxetane ring has evolved as a useful bioisostere for dimethyl and carbonyl groups for the improvement of physiochemical properties of drug candidates. Herein, we report the generation and utilization of highly unstable 3-oxetanyllithium as a hitherto unexplored nucleophile leveraging flash technology. A range of different electrophiles are suitable reaction partners in this protocol, and we demonstrate the utility of this protocol in late-stage pharmaceutical analogue synthesis.

16.
Eur J Med Chem ; 274: 116511, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-38820854

RESUMO

A structure-based drug design approach was focused on incorporating phenyl ring heterocyclic bioisosteres into coumarin derivative 1, previously reported as potent dual AChE-MAO B inhibitor, with the aim of improving drug-like features. Structure-activity relationships highlighted that bioisosteric rings were tolerated by hMAO B enzymatic cleft more than hAChE. Interestingly, linker homologation at the basic nitrogen enabled selectivity to switch from hAChE to hBChE. In the present work, we identified thiophene-based isosteres 7 and 15 as dual AChE-MAO B (IC50 = 261 and 15 nM, respectively) and BChE-MAO B (IC50 = 375 and 20 nM, respectively) inhibitors, respectively. Both 7 and 15 were moderately water-soluble and membrane-permeant agents by passive diffusion (PAMPA-HDM). Moreover, they were able to counteract oxidative damage induced by both H2O2 and 6-OHDA in SH-SY5Y cells and predicted to penetrate into CNS in a cell-based model mimicking blood-brain barrier. Molecular dynamics (MD) simulations shed light on key differences in AChE and BChE recognition processes promoted by the basic chain homologation from 7 to 15.


Assuntos
Acetilcolinesterase , Butirilcolinesterase , Inibidores da Colinesterase , Desenho de Fármacos , Inibidores da Colinesterase/farmacologia , Inibidores da Colinesterase/química , Inibidores da Colinesterase/síntese química , Humanos , Acetilcolinesterase/metabolismo , Relação Estrutura-Atividade , Butirilcolinesterase/metabolismo , Estrutura Molecular , Relação Dose-Resposta a Droga , Simulação de Dinâmica Molecular , Cumarínicos/química , Cumarínicos/farmacologia , Cumarínicos/síntese química , Linhagem Celular Tumoral
17.
Cancers (Basel) ; 15(3)2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36765929

RESUMO

Chemotherapy and immunotherapy have markedly improved the management of several malignancies. However, not all cancer patients respond primarily to such therapies, and others can become resistant during treatment. Thus, identification of the factors/mechanisms underlying cancer resistance to such treatments could help develop novel effective therapeutic compounds. Tumor-associated macrophages (TAMs), myeloid-derived suppressor cells (MDSCs), and regulatory T cells (Tregs) are major components of the suppressive tumor microenvironment and are critical drivers of immunosuppression, creating a tumor-promoting and drug-resistant niche. In this regard, therapeutic strategies to tackle immunosuppressive cells are an interesting option to increase anti-tumor immune responses and overcome the occurrence of drug resistance. Accumulating evidence indicates that interleukin-34 (IL-34), a cytokine produced by cancer cells, and/or TAMs act as a linker between induction of a tumor-associated immunosuppressive microenvironment and drug resistance. In this article, we review the current data supporting the role of IL-34 in the differentiation/function of immune suppressive cells and, hence, in the mechanisms leading to therapeutic resistance in various cancers.

18.
Cancers (Basel) ; 15(8)2023 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-37190146

RESUMO

Minimally invasive liver resection (MILR) is being widely utilized owing to recent advancements in laparoscopic and robot-assisted surgery. There are two main types of liver resection: anatomical (minimally invasive anatomical liver resection (MIALR)) and nonanatomical. MIALR is defined as a minimally invasive liver resection along the respective portal territory. Optimization of the safety and precision of MIALR is the next challenge for hepatobiliary surgeons, and intraoperative indocyanine green (ICG) staining is considered to be of considerable importance in this field. In this article, we present the latest findings on MIALR and laparoscopic anatomical liver resection using ICG at our hospital.

19.
BMJ Open ; 13(9): e072926, 2023 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-37730389

RESUMO

INTRODUCTION: Knowledge of the clinical liver anatomy has evolved with advanced imaging modalities and laparoscopic surgery. Therefore, precise anatomical resection knowledge has become the standard treatment for primary and secondary liver cancer. Segmentectomy, a parenchymal-preserving approach, is regarded as an option for anatomical resections in patients with impaired liver. Indocyanine green (ICG) staining is a promising method for understanding the anatomical borders of the liver segments. There are two methods of ICG staining (positive and negative), and the superiority of either approach has not been determined to date. METHODS AND ANALYSIS: This is a prospective randomised controlled superiority clinical trial performed in a single centre tertiary hospital in Japan. A comparison between the accuracy of positive and negative ICG staining in guiding laparoscopic anatomical liver resection is planned in this study. Possible candidates are patients with liver malignant tumours in whom laparoscopic monosegmentectomy or subsegmentectomy is planned. Fifty patients will be prospectively allocated into the following two groups: group A, ICG-negative staining group, and group B, ICG-positive staining group. The optimal dose of ICG for positive staining will be determined during the preparation phase. To assess the ability of the ICG fluorescence guidance in anatomical resection, the primary endpoint is the success rate of ICG staining, which consists of a SOS based on three components: superficial demarcation in the liver surface, visualisation of the parenchymal borders and consistency with the preoperative three-dimensional simulation. The secondary endpoints are the evaluation of short-term surgical outcomes and recurrence-free survival. ETHICS AND DISSEMINATION: The study was approved by Ageo Central General Hospital Clinical Research Ethical Committee (No: 1044) and it carried out following the Declaration of Helsinki (2013 revision). Informed consent will be taken from the patients before participating. The findings will be disseminated through peer-reviewed publications, scientific meetings and conferences. TRIAL REGISTRATION NUMBER: UMIN000049815.


Assuntos
Laparoscopia , Neoplasias Hepáticas , Humanos , Coloração Negativa , Verde de Indocianina , Estudos Prospectivos , Coloração e Rotulagem , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/cirurgia , Ensaios Clínicos Controlados Aleatórios como Assunto
20.
Chem Commun (Camb) ; 59(10): 1373-1376, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36649092

RESUMO

A direct nucleophilic monofluoroalkylation strategy leveraging on lithium fluorocarbenoids has been developed. Flow microreactor technology allows capitalization of the synthetic potential of these scarcely explored short-lived intermediates - namely 1-fluoro-2-phenylethyllithium, 1-fluoro-3-phenylpropyllithium, and 1-fluorononyllithium - generated through lithium/iodine exchange reaction. This robust protocol was employed to prepare new fluorinated products, adopting various classes of electrophiles. The inherent advantages of microreactor technology contribute to rendering this approach a new valuable tool for direct fluoroalkylation chemistry.

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