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1.
Cell Mol Gastroenterol Hepatol ; : 101376, 2024 Jul 03.
Article in English | MEDLINE | ID: mdl-38969206

ABSTRACT

BACKGROUND & AIMS: Restricted gastric motor functions contribute to aging-associated under-nutrition, sarcopenia, and frailty. We previously identified a decline in interstitial cells of Cajal (ICC, gastrointestinal pacemaker and neuromodulator cells) and their stem cells (ICC-SC) as a key factor of gastric aging. Altered functionality of the histone methyltransferase enhancer of zeste homolog 2 (EZH2) is central to organismal aging. Here, we investigated the role of EZH2 in the aging-related loss of ICC/ICC-SC. METHODS: klotho mice, a model of accelerated aging, were treated with the most clinically advanced EZH2 inhibitor, EPZ6438 (tazemetostat; 160 mg/kg i.p. BID for 3 weeks). Gastric ICC were analyzed by western blotting (WB) and immunohistochemistry. ICC and ICC-SC were quantified by flow cytometry. Gastric slow wave activity was assessed by intracellular electrophysiology. Ezh2 was deactivated in ICC by treating KitcreERT2/+;Ezh2fl/fl mice with tamoxifen. TRP53, a key mediator of aging-related ICC loss, was induced with nutlin 3a in gastric muscle organotypic cultures and an ICC-SC line. RESULTS: In klotho mice, EPZ6438 treatment mitigated the decline in the ICC growth factor KIT ligand/stem cell factor and gastric ICC. EPZ6438 also improved gastric slow wave activity and mitigated the reduced food intake and impaired body weight gain characteristic of this strain. Conditional genomic deletion of Ezh2 in Kit-expressing cells also prevented ICC loss. In organotypic cultures and ICC-SC, EZH2 inhibition prevented the aging-like effects of TRP53 stabilization on ICC/ICC-SC. CONCLUSIONS: Inhibition of EZH2 with EPZ6438 mitigates aging-related ICC/ICC-SC loss and gastric motor dysfunction, improving slow wave activity and food intake in klotho mice.

2.
Surg Case Rep ; 10(1): 141, 2024 Jun 11.
Article in English | MEDLINE | ID: mdl-38861227

ABSTRACT

BACKGROUND: Thromboembolic occlusion of the superior mesenteric artery (SMA) is a grave complication in individuals diagnosed with atrial fibrillation (AF). This condition often necessitates extensive bowel resection, culminating in short bowel syndrome, which presents challenges for anticoagulant administration and/or antiarrhythmic therapy. CASE PRESENTATION: Presented here are findings of two patients, aged 78 and 72 years, respectively, who underwent comprehensive thoracoscopic AF surgery subsequent to extensive small bowel resection following SMA embolization. In each, onset of AF precipitated an embolic event, while the concurrent presence of short bowel syndrome complicated anticoagulation management. Total thoracoscopic AF surgery, comprised stapler-closure of the left atrial appendage (LAA) and bilateral epicardial clamp-isolation of the pulmonary veins, an operative modality aimed at addressing AF rhythm control and mitigating embolic events such as cerebral infarction, led to favorable outcomes in both cases. Additionally, computed tomography (CT) conducted one month post-surgery revealed the absence of residual tissue in the LAA, with the left atrium demonstrating a well-rounded, spherical shape. At the time of writing, the patients have remained asymptomatic following surgery regarding thromboembolic and arrhythmic manifestations for 29 and 10 months, respectively, notwithstanding the absence of anticoagulant or antiarrhythmic pharmacotherapy. Additionally, electrocardiographic surveillance has revealed persistent sinus rhythm. CONCLUSIONS: The present findings underscore the feasibility and efficacy of a total thoracoscopic AF surgery procedure for patients presented with short bowel syndrome complicating SMA embolization, thus warranting consideration for its broader clinical application.

3.
Chem Sci ; 15(15): 5627-5632, 2024 Apr 17.
Article in English | MEDLINE | ID: mdl-38638214

ABSTRACT

Highly substituted trans-hydrindanes were synthesized by the three-component coupling reactions of 1,3-diethyl 2-(2-oxopropylidene)propanedioate and two different α,ß-unsaturated aldehydes catalyzed by diphenylprolinol silyl ether. The reaction proceeds via two successive independent catalytic domino reactions in a one-pot reaction by a single chiral catalyst. Domino reactions involve Michael/Michael and Michael/aldol reactions to afford trans-hydrindanes with excellent diastereoselectivity and nearly optically pure form.

4.
J Smooth Muscle Res ; 60: 1-9, 2024.
Article in English | MEDLINE | ID: mdl-38462479

ABSTRACT

Macrophages are the originators of inflammatory compounds, phagocytic purifiers in their local environment, and wound healing protectors in oxidative environments. They are molded by the tissue milieu they inhabit, with gastrointestinal (GI) muscularis macrophages (MMs) being a prime example. MMs are located in the muscular layer of the GI tract and contribute to muscle repair and maintenance of GI motility. MMs are often in close proximity to the enteric nervous system, specifically near the enteric neurons and interstitial cells of Cajal (ICCs). Consequently, the anti-inflammatory function of MMs corresponds to the development and maintenance of neural networks in the GI tract. The capacity of MMs to shift from anti-inflammatory to proinflammatory states may contribute to the inflammatory aspects of various GI diseases and disorders such as diabetic gastroparesis or postoperative ileus, functional disorders such as irritable bowel syndrome, and organic diseases such as inflammatory bowel disease. We reviewed the current knowledge of MMs and their influence on neighboring cells due to their important role in the GI tract.


Subject(s)
Enteric Nervous System , Anti-Inflammatory Agents , Gastrointestinal Motility , Gastrointestinal Tract , Macrophages , Muscles , Humans
5.
Rev Sci Instrum ; 95(1)2024 Jan 01.
Article in English | MEDLINE | ID: mdl-38240678

ABSTRACT

Understanding the pressure-induced structural changes in liquids and amorphous materials is fundamental in a wide range of scientific fields. However, experimental investigation of the structure of liquid and amorphous material under in situ high-pressure conditions is still limited due to the experimental difficulties. In particular, the range of the momentum transfer (Q) in the structure factor [S(Q)] measurement under high-pressure conditions has been limited at relatively low Q, which makes it difficult to conduct detailed structural analysis of liquid and amorphous material. Here, we show the in situ high-pressure pair distribution function measurement of liquid and glass by using the 100 keV pink beam. Structures of liquids and glasses are measured under in situ high-pressure conditions in the Paris-Edinburgh press by high-energy x-ray diffraction measurement using a double-slit collimation setup with a point detector. The experiment enables us to measure S(Q) of GeO2 and SiO2 glasses and liquid Ge at a wide range of Q up to 20-29 Å-1 under in situ high-pressure and high-temperature conditions, which is almost two times larger than that of the conventional high-pressure angle-dispersive x-ray diffraction measurement. The high-pressure experimental S(Q) precisely determined at a wide range of Q opens the way to investigate detailed structural features of liquids and amorphous materials under in situ high-pressure and high-temperature conditions, as well as ambient pressure study.

6.
Nat Commun ; 14(1): 7851, 2023 Dec 07.
Article in English | MEDLINE | ID: mdl-38062025

ABSTRACT

While polymorphism is prevalent in crystalline solids, polyamorphism draws increasing interest in various types of amorphous solids. Recent studies suggested that supercooling of liquid phase-change materials (PCMs) induces Peierls-like distortions in their local structures, underlying their liquid-liquid transitions before vitrification. However, the mechanism of how the vitrified phases undergo a possible polyamorphic transition remains elusive. Here, using high-energy synchrotron X-rays, we can access the precise pair distribution functions under high pressure and provide clear evidence that pressure can reverse the Peierls-like distortions, eliciting a polyamorphic transition in GeTe and GeSe. Combined with simulations based on machine-learned-neural-network potential, our structural analysis reveals a high-pressure state characterized by diminished Peierls-like distortion, greater coherence length, reduced compressibility, and a narrowing bandgap. Our finding underscores the crucial role of Peierls-like distortions in amorphous octahedral systems including PCMs. These distortions can be controlled through pressure and composition, offering potentials for designing properties in PCM-based devices.

7.
J Synchrotron Radiat ; 30(Pt 6): 1108-1113, 2023 Nov 01.
Article in English | MEDLINE | ID: mdl-37850563

ABSTRACT

The spatial resolution in scanning-based two-dimensional microscopy is normally limited by the size of the probe, thereby a smaller probe is a prerequisite for enhancing the spatial resolution. For three-dimensional microscopy that combines translation and rotation motions of a specimen, however, complex trajectories of the probe highly overlap in the specimen, which could change the postulate above. Here, the spatial resolution achieved in scanning three-dimensional X-ray diffraction (s3DXRD) microscopy is investigated. In this method, the most appropriate orientation of the pixel in the specimen coordinate is selected by comparing the completeness of diffraction peaks with theory. Therefore, the superposed area of the beam trajectory has a strong effect on the spatial resolution, in terms of the completeness of diffraction peaks. It was found that the highly superposed area by the incident X-rays, which has the highest completeness factor in the pixel of the specimen, is much smaller than the X-ray probe size, and that sub-pixel analysis by dividing a pixel into small pieces leads to drastic improvement of the spatial resolution in s3DXRD.

8.
IJU Case Rep ; 6(5): 282-285, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37667762

ABSTRACT

Introduction: Transient decrease in serum prostate-specific antigen level can occur after abiraterone acetate withdrawal in male patient with metastatic castration-resistant prostate cancer. Here, we report a case of abiraterone acetate withdrawal syndrome with transient prostate-specific antigen decrease after progression to castration-resistant disease while using upfront abiraterone therapy for high-risk prostate cancer. Case presentation: A 73-year-old man with hormone-sensitive high-risk prostate cancer with multiple bone metastases (prostate-specific antigen level, 294.109 ng/mL) received upfront abiraterone/prednisolone combination and androgen deprivation therapy. One year later, prostate-specific antigen level decreased to 0.017 ng/mL (nadir) but it gradually rose by 15 months after treatment initiation. He was diagnosed as castration-resistant and new bone metastases appeared. After abiraterone was discontinued, prostate-specific antigen level decreased and stabilized at a low level for 5 months. Conclusion: Abiraterone acetate withdrawal syndrome was observed when hormone-sensitive prostate cancer with upfront abiraterone therapy progressed to castration-resistant prostate cancer.

9.
Biomolecules ; 13(9)2023 Sep 07.
Article in English | MEDLINE | ID: mdl-37759758

ABSTRACT

Neurointestinal diseases result from dysregulated interactions between the nervous system and the gastrointestinal (GI) tract, leading to conditions such as Hirschsprung's disease and irritable bowel syndrome. These disorders affect many people, significantly diminishing their quality of life and overall health. Central to GI motility are the interstitial cells of Cajal (ICC), which play a key role in muscle contractions and neuromuscular transmission. This review highlights the role of ICC in neurointestinal diseases, revealing their association with various GI ailments. Understanding the functions of the ICC could lead to innovative perspectives on the modulation of GI motility and introduce new therapeutic paradigms. These insights have the potential to enhance efforts to combat neurointestinal diseases and may lead to interventions that could alleviate or even reverse these conditions.

10.
Chem Sci ; 14(37): 10081-10086, 2023 Sep 27.
Article in English | MEDLINE | ID: mdl-37772091

ABSTRACT

The enantioselective total synthesis of latanoprost, an antiglaucoma agent, has been accomplished with excellent diastereo- and enantioselectivities in a pot-economical manner using six reaction vessels. An enantioselective Krische allylation was conducted in the first pot. In the second pot, olefin metathesis, silyl protection, and hydrogenolysis proceeded efficiently. In the third pot, an organocatalyst-mediated Michael reaction proceeded with excellent diastereoselectivity. The fourth pot involved a substrate-controlled Mukaiyama intramolecular aldol reaction and elimination of HNO2 to afford a methylenecyclopentanone, also with excellent diastereoselectivity. The fifth pot involved a Michael reaction of vinyl cuprate. In the sixth pot, three reactions, a cis-selective olefin metathesis, diastereoselective reduction, and deprotection, afforded latanoprost. Nearly optically pure latanoprost was obtained, and the total yield was 24%.

11.
Gastroenterology ; 165(6): 1458-1474, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37597632

ABSTRACT

BACKGROUND & AIMS: Although depletion of neuronal nitric oxide synthase (NOS1)-expressing neurons contributes to gastroparesis, stimulating nitrergic signaling is not an effective therapy. We investigated whether hypoxia-inducible factor 1α (HIF1A), which is activated by high O2 consumption in central neurons, is a Nos1 transcription factor in enteric neurons and whether stabilizing HIF1A reverses gastroparesis. METHODS: Mice with streptozotocin-induced diabetes, human and mouse tissues, NOS1+ mouse neuroblastoma cells, and isolated nitrergic neurons were studied. Gastric emptying of solids and volumes were determined by breath test and single-photon emission computed tomography, respectively. Gene expression was analyzed by RNA-sequencing, microarrays, immunoblotting, and immunofluorescence. Epigenetic assays included chromatin immunoprecipitation sequencing (13 targets), chromosome conformation capture sequencing, and reporter assays. Mechanistic studies used Cre-mediated recombination, RNA interference, and clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated protein 9 (Cas9)-mediated epigenome editing. RESULTS: HIF1A signaling from physiological intracellular hypoxia was active in mouse and human NOS1+ myenteric neurons but reduced in diabetes. Deleting Hif1a in Nos1-expressing neurons reduced NOS1 protein by 50% to 92% and delayed gastric emptying of solids in female but not male mice. Stabilizing HIF1A with roxadustat (FG-4592), which is approved for human use, restored NOS1 and reversed gastroparesis in female diabetic mice. In nitrergic neurons, HIF1A up-regulated Nos1 transcription by binding and activating proximal and distal cis-regulatory elements, including newly discovered super-enhancers, facilitating RNA polymerase loading and pause-release, and by recruiting cohesin to loop anchors to alter chromosome topology. CONCLUSIONS: Pharmacologic HIF1A stabilization is a novel, translatable approach to restoring nitrergic signaling and treating diabetic gastroparesis. The newly recognized effects of HIF1A on chromosome topology may provide insights into physioxia- and ischemia-related organ function.


Subject(s)
Diabetes Mellitus, Experimental , Gastroparesis , Animals , Female , Humans , Mice , Diabetes Mellitus, Experimental/complications , Diabetes Mellitus, Experimental/genetics , Epigenesis, Genetic , Gastroparesis/genetics , Neurons , Nitric Oxide Synthase Type I
12.
Cell Mol Gastroenterol Hepatol ; 16(3): 369-383, 2023.
Article in English | MEDLINE | ID: mdl-37301443

ABSTRACT

BACKGROUND & AIMS: Impaired gastric motor function in the elderly causes reduced food intake leading to frailty and sarcopenia. We previously found that aging-related impaired gastric compliance was mainly owing to depletion of interstitial cells of Cajal (ICC), pacemaker cells, and neuromodulator cells. These changes were associated with reduced food intake. Transformation-related protein 53-induced suppression of extracellular signal-regulated protein kinase (ERK)1/2 in ICC stem cell (ICC-SC) cell-cycle arrest is a key process for ICC depletion and gastric dysfunction during aging. Here, we investigated whether insulin-like growth factor 1 (IGF1), which can activate ERK in gastric smooth muscles and invariably is reduced with age, could mitigate ICC-SC/ICC loss and gastric dysfunction in klotho mice, a model of accelerated aging. METHODS: Klotho mice were treated with the stable IGF1 analog LONG R3 recombinant human (rh) IGF1 (150 µg/kg intraperitoneally twice daily for 3 weeks). Gastric ICC/ICC-SC and signaling pathways were studied by flow cytometry, Western blot, and immunohistochemistry. Gastric compliance was assessed in ex vivo systems. Transformation-related protein 53 was induced with nutlin 3a and ERK1/2 signaling was activated by rhIGF-1 in the ICC-SC line. RESULTS: LONG R3 rhIGF1 treatment prevented reduced ERK1/2 phosphorylation and gastric ICC/ICC-SC decrease. LONG R3 rhIGF1 also mitigated the reduced food intake and impaired body weight gain. Improved gastric function by LONG R3 rhIGF1 was verified by in vivo systems. In ICC-SC cultures, rhIGF1 mitigated nutlin 3a-induced reduced ERK1/2 phosphorylation and cell growth arrest. CONCLUSIONS: IGF1 can mitigate age-related ICC/ICC-SC loss by activating ERK1/2 signaling, leading to improved gastric compliance and increased food intake in klotho mice.


Subject(s)
Insulin , Interstitial Cells of Cajal , Aged , Animals , Humans , Mice , Aging , Insulin/metabolism , Interstitial Cells of Cajal/metabolism , MAP Kinase Signaling System , Stomach
13.
Int J Mol Sci ; 24(12)2023 Jun 06.
Article in English | MEDLINE | ID: mdl-37372958

ABSTRACT

Due to modern medical advancements, greater proportions of the population will continue to age with longer life spans. Increased life span, however, does not always correlate with improved health span, and may result in an increase in aging-related diseases and disorders. These diseases are often attributed to cellular senescence, in which cells become disengaged from the cell cycle and inert to cell death. These cells are characterized by a proinflammatory secretome. The proinflammatory senescence-associated secretory phenotype, although part of a natural function intended to prevent further DNA damage, creates a microenvironment suited to tumor progression. This microenvironment is most evident in the gastrointestinal tract (GI), where a combination of bacterial infections, senescent cells, and inflammatory proteins can lead to oncogenesis. Thus, it is important to find potential senescence biomarkers as targets of novel therapies for GI diseases and disorders including cancers. However, finding therapeutic targets in the GI microenvironment to reduce the risk of GI tumor onset may also be of value. This review summarizes the effects of cellular senescence on GI aging, inflammation, and cancers, and aims to improve our understanding of these processes with a goal of enhancing future therapy.


Subject(s)
Cellular Senescence , Neoplasms , Humans , Neoplasms/metabolism , Inflammation , Gastrointestinal Tract/metabolism , Tumor Microenvironment
14.
Chemistry ; 29(40): e202301093, 2023 Jul 14.
Article in English | MEDLINE | ID: mdl-37147185

ABSTRACT

Substituted quinolines, tricyclic and tetracyclic molecules with a quinoline moiety are synthesized by a domino reaction from dicyanoalkenes and 3-aryl-pent-2-en-4-ynals in one pot. We established two methods: one is catalyzed by chiral diphenylprolinol silyl ether, and the other is catalyzed by di(2-ethyl)hexylamine, in combination with p-nitrophenol. A wide variety of dicyanoalkenes can be employed. As the catalysts are secondary amines, and water is the only by-product, this is an environmentally benign synthetic method for the preparation of substituted quinolines.

15.
IJU Case Rep ; 6(1): 51-53, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36605681

ABSTRACT

Introduction: The main causes of secondary male infertility are varicocele and aging. It is rarely caused by adult-onset hypopituitarism. The onset of hypopituitarism is often due to brain tumors, trauma, surgery, or congenital disorders. Case presentation: A 29-year-old man was admitted to the hospital with complaints of decreased libido and semen volume, which lasted for 4 months. He had no abnormalities in adolescence and has a 2-year-old child. Blood tests showed low luteinizing hormone and follicle-stimulating hormone, and semen tests showed azoospermia. Magnetic resonance imaging T1-weighted images showed swelling and enhancement effect of the pituitary gland, and lymphocytic hypophysitis was suspected. After an Insulin-thyroid-stimulating hormone releasing hormone-luteinizing hormone-releasing hormone test, a decrease in luteinizing hormone/follicle-stimulating hormone secretion was considered. We diagnosed hypogonadotropic hypogonadism due to lymphocytic hypophysitis. Currently, the patient is being treated with a hormone replacement therapy. Conclusion: We experienced a case of hypogonadotropic hypogonadism due to lymphocytic hypophysitis discovered by secondary infertility.

16.
Int J Urol ; 30(9): 723-729, 2023 09.
Article in English | MEDLINE | ID: mdl-36578154

ABSTRACT

OBJECTIVES: When primary treatment has been inadequate, nivolumab and axitinib are often used as a secondary treatments for patients with metastatic renal cell carcinoma (mRCC). However, there have been few reports comparing the efficacy and safety of these drugs. METHODS: We retrospectively investigated 58 patients treated with nivolumab and 57 patients treated with axitinib as secondary treatment between April 2013 and December 2019. We then assessed the clinical efficacy and safety of the treatments in both groups. RESULTS: The most common primary therapy was sunitinib (61.7%). Both nivolumab and axitinib groups showed no significant differences in terms of the objective response rate and disease control rate (p = 0.280 and p = 0.518, respectively). Importantly, progression-free survival (PFS) and overall survival (OS) seemed to be similar in patients treated with nivolumab and axitinib (p = 0.527 and p = 0.266, respectively), irrespective of the objective response to primary therapy. Furthermore, a Cox proportional hazards model showed that pretreatment Karnofsky Performance Status was significantly associated with PFS and OS. Although the incidence of adverse events was significantly higher in the patients treated with axitinib, there was no significant difference in time to treatment failure between the two groups. CONCLUSIONS: Nivolumab and axitinib showed similar clinical benefits as secondary treatment in patients with mRCC; thus, they should be an option in sequential therapy following treatment with tyrosine kinase inhibitors (TKIs). Future studies and feasible therapeutic biomarkers would help predict the clinical response to TKIs or immune checkpoint inhibitors in patients with mRCC.


Subject(s)
Antineoplastic Agents , Carcinoma, Renal Cell , Kidney Neoplasms , Humans , Carcinoma, Renal Cell/pathology , Axitinib/adverse effects , Nivolumab/adverse effects , Retrospective Studies , Antineoplastic Agents/adverse effects , Japan , Kidney Neoplasms/pathology
17.
Int J Urol ; 30(1): 70-76, 2023 01.
Article in English | MEDLINE | ID: mdl-36305578

ABSTRACT

OBJECTIVES: Approximately, 90% of men with advanced prostate cancer will develop bone metastasis. However, there have been few reports about noninvasive biomarker to detect and predict clinical outcome of bone metastasis (BM) in prostate cancer patients. METHODS: We examined 1127 patients who underwent prostate biopsy from August 2012 to June 2017. We also investigated bone turnover markers such as bone-specific alkaline phosphatase, type I collagen cross-linked N-terminal telopeptide, C-terminal pyridinoline cross-linked telopeptide of type I collagen, and tartrate-resistant acid phosphatase type 5b (TRACP 5b). RESULTS: A total of 282 patients were diagnosed as prostate cancer with complete clinical data, and 34 patients with bone metastasis. Multivariate analysis revealed C-terminal pyridinoline cross-linked telopeptide of type I collagen, tartrate-resistant acid phosphatase type 5b, and prostate-specific antigen (PSA) were independent biomarkers in detection of BM (p < 0.05, respectively). Furthermore, we developed predictive model formula based on tartrate-resistant acid phosphatase type 5b and PSA, for which the area under the curve was 0.95. In patients with bone metastasis, multivariate cox proportional hazards analysis revealed that this model was significantly associated with poor clinical outcome of cancer-specific survival (p < 0.05). In validation cohort with 137 patients, we also confirmed the utility of this model for diagnosis of BM (the area under the curve = 0.95). CONCLUSIONS: Our developed formula of tartrate-resistant acid phosphatase type 5b in accordance with PSA may serve as the useful tool in diagnosis and prediction of clinical outcome for prostate cancer with bone metastasis.


Subject(s)
Bone Neoplasms , Prostatic Neoplasms , Male , Humans , Tartrate-Resistant Acid Phosphatase , Prostate-Specific Antigen , Prognosis , Acid Phosphatase , Collagen Type I , Biomarkers, Tumor , Bone Neoplasms/secondary , Prostatic Neoplasms/diagnosis , Prostatic Neoplasms/pathology , Biomarkers
18.
Chem Rec ; 23(7): e202200159, 2023 Jul.
Article in English | MEDLINE | ID: mdl-35896950

ABSTRACT

The aldol reaction is one of the most important carbon-carbon bond-forming reactions in organic chemistry. Asymmetric direct cross-aldol reaction of two different aldehydes has been regarded as a difficult reaction because of the side reactions such as self-aldol reaction and over reaction. We found that trifluoromethyl-substituted diarylprolinol, α,α-bis[3,5-bis(trifluoromethyl)phenyl]-2-pyrrolidinemethanol (1), is an effective organocatalyst that promotes several cross-aldol reactions of aldehydes with excellent diastereo- and enantioselectivities. Acetaldehyde can be employed as a suitable nucleophilic aldehyde. Successful electrophilic aldehydes are ethyl glyoxylate, chloroacetaldehyde, dichloroacetaldehyde, chloral, α-alkyl-α-oxo aldehyde, trifluoroacetaldehyde, glyoxal, alkenyl aldehyde, alkynyl aldehyde, and formaldehyde. Some of the aldehydes are commercially available as a polymer solution, an aqueous solution, or in the hydrated form. They can be used directly in the asymmetric aldol reaction as a commercially available form, which is a synthetic advantage. Given that the obtained aldol products possess several functional groups along with a formyl moiety, they are synthetically useful chiral building blocks.


Subject(s)
Aldehydes , Water , Catalysis , Carbon
19.
Nat Commun ; 13(1): 7503, 2022 12 07.
Article in English | MEDLINE | ID: mdl-36477407

ABSTRACT

In this work, the enantioselective total synthesis of (-)-quinine has been accomplished in a pot-economical manner using five reaction vessels. In the first pot, reactions involve the diphenylprolinol silyl ether-mediated Michael reaction, aza-Henry reaction, hemiaminalization, and elimination of HNO2 (five reactions), affording a chiral tetrahydropyridine with excellent enantioselectivity. In the second pot, five reactions proceed with excellent diastereoselectivity to afford a trisubstituted piperidine with the desired stereochemistry. A further five reactions are carried out in the last one-pot sequence.


Subject(s)
Quinine
20.
Sci Rep ; 12(1): 16642, 2022 10 05.
Article in English | MEDLINE | ID: mdl-36198773

ABSTRACT

During tumorigenesis, certain tissues are colonized by mutant clones with oncogenic driver mutations as precancer lesions. These mutations can facilitate clonal expansion and may contribute to malignant transformation. The molecular features of low-grade non-muscle invasive bladder cancer (NMIBC) and high-grade bladder cancer are so distinct that they are thought to follow different evolutionary tumorigenesis pathways. Although NMIBC accounts for most bladder tumors, the somatic mutation patterns in "precancer" urothelium of patients with NMIBC remain unclear. Here, we analyzed specimens of normal urothelium and bladder tumors from patients with low-grade and high-grade NMIBC and investigated the genomic evolution of the cancer. Somatic mutations were analyzed using 50 oncogene-targeted sequences and droplet digital polymerase chain reaction for TERT promoter mutations. Somatic mutations in TERT promoter, FGFR3, and CDKN2A were characteristically identified in the normal urothelium of patients with NMIBC. These mutations, consistently identified in both tumor and normal specimens, likely affect clonal expansion during the malignant transformation of NMIBC. Though larger samples and comprehensive study are warranted to confirm our results, the difference in mutational landscape of the precancerous urothelium of patients with bladder cancer could offer deeper understandings of genomic evolution in bladder tumorigenesis.


Subject(s)
Urinary Bladder Neoplasms , Cell Transformation, Neoplastic/metabolism , Humans , Mutation , Urinary Bladder/pathology , Urinary Bladder Neoplasms/pathology , Urothelium/pathology
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