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1.
Eur Spine J ; 2024 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-39369370

RESUMO

PURPOSE: This study aimed to evaluate the analgesic effects and safety of multidrug cocktail injections for postoperative pain management in patients undergoing lumbar microendoscopic decompression surgery. METHODS: A prospective randomized controlled trial was conducted with 70 patients who underwent lumbar microendoscopic decompression surgery between December 2023 and May 2024. Patients were randomly assigned to receive either a multidrug cocktail injection (cocktail group, n = 35) or no cocktail injection (non-cocktail group, n = 35). Primary outcomes included scores of the numerical rating scale (NRS) for pain from postoperative days 1 to 7 and the number of analgesics used within the first 3 postoperative days. Secondary outcomes included sex, age, body mass index, preoperative diagnosis, surgical levels, duration of surgery, blood loss, C-reactive protein (CRP) levels on postoperative day 1, and drain output. RESULTS: The cocktail group experienced significantly lower pain levels from postoperative days 1 to 7 (p < 0.05) and used fewer analgesics within the first 3 days (p = 0.01) compared with the non-cocktail group. Additionally, the cocktail group had significantly lower CRP levels (p < 0.001) and a shorter hospital stay (p = 0.01). No significant differences were observed in the duration of surgery, blood loss, or drain output between the groups. CONCLUSION: Multidrug cocktail injections are effective and safe for postoperative pain management in lumbar microendoscopic decompression surgery, significantly reducing pain, analgesic use, CRP levels, and hospital stay. These findings suggest that incorporating multidrug cocktail injections into postoperative care protocols can enhance patient recovery and outcomes.

2.
ACS Cent Sci ; 10(8): 1481-1489, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39220706

RESUMO

Carbohydrates regulate an inimitable spectrum of biological functions, yet successfully leveraging this therapeutic avenue continues to be frustrated by low affinities with glycan-specific proteins. A conspicuous exception is the interaction of monosialotetrahexosylganglioside (GM1) with the carbohydrate-recognition domain of cholera toxin from Vibrio cholerae: this is one of the strongest protein-carbohydrate interactions known. To establish the importance of a long-discussed key hydrogen bond between C2 of the terminal galactose of GM1 and the B subunit pentamer of cholera toxin (CTB5), the total synthesis of a selectively fluorinated GM1 epitope was conducted in 19 steps. This process of molecular editing (Oδ-H → Fδ-) strategically deletes the hydrogen bond donor while retaining the localized partial charge of the substituent. Comparison of the binding affinity of F-GM1/CTB5 with native GM1, the GM1 carbohydrate epitope, and meta-mononitrophenyl-α-galactoside (MNPG) revealed a trend that fully supports the importance of this key interaction. These NMR data suggest that F-GM1 binds in a closely similar conformation as native GM1. Crystallographic analyses of the complex also confirm that the OH → F bioisosteric exchange at C2 of the terminal galactose induces a ring conformation that eliminates key hydrogen bonds: these interactions are compensated for by inter- and intramolecular fluorine-specific interactions.

3.
Dalton Trans ; 53(14): 6256-6263, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38501342

RESUMO

Bottom-up synthesis of siloxane-based nanoporous materials from siloxane oligomers is promising for constructing well-defined structures at a molecular level. Herein, we report the synthesis of nanoporous materials consisting of cage-type siloxanes through the nonhydrolytic siloxane bond formation reaction. Cage siloxanes with double-n-ring geometries (n = 4 or 6) modified with dimethylsilyl and dimethylethoxysilyl groups are synthesized and directly cross-linked using a B(C6F5)3 catalyst, resulting in the formation of porous networks composed of alternating cage siloxane nodes and tetramethyldisiloxane (-SiMe2OSiMe2-) linkers. Compared with conventional hydrolysis and polycondensation reactions of alkoxysilyl-modified cage siloxanes under acid conditions, the non-hydrolytic condensation reaction was found favorable for the formation of porous siloxane networks without unwanted cleavage of the siloxane bonds.

4.
Chemistry ; 30(17): e202304080, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38200698

RESUMO

Utilization of well-defined siloxane molecules allows for the construction of functional siloxane-based nanoporous materials based on the molecular design. Herein, a novel class of siloxane-based porous materials is synthesized via cross-linking of dimethylsilyl- and dimethylvinylsilyl-functionalized cage siloxanes with double-6-ring (D6R) geometry. Compared with the conventional double-4-ring cage siloxane, this study highlights the characteristics of D6R siloxanes as building blocks, demonstrating their high surface area and chemical stability. Furthermore, density functional theory calculations show their unique cation encapsulation ability.

5.
Adv Sci (Weinh) ; 10(27): e2303655, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37505433

RESUMO

Self-healing ability is crucial to increasing the lifetime and reliability of materials. In this study, spatiotemporal control of the healing of a polysiloxane material is achieved using a cleavable cage compound encapsulating a fluoride ion (F- ), which triggeres the dynamic rearrangement of the siloxane (Si-O-Si) networks. A self-healing siloxane-based elastomer is prepared by cross-linking polydimethylsiloxane (PDMS) with a F- -encapsulating cage-type germoxane (Ge-O-Ge) compound. This material can self-heal repeatedly under humid conditions. The F- released by hydrolytic cleavage of the cage framework contributes to rejoining of the cut pieces by promoting the local rearrangement of the siloxane networks. The use of a molecular cage encapsulating a catalyst for dynamic bond rearrangement provides a new concept for designing self-healing polysiloxane materials based on integrated extrinsic and intrinsic mechanisms.

6.
Dalton Trans ; 50(24): 8497-8505, 2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34047738

RESUMO

Double-four ring (D4R)-type cage germanoxanes, having a fluoride anion in the cage, contain organic ammonium cations as counter cations outside the cage, and they are attractive as unique nano-building blocks of anionic porous materials. Although the variety of counter cations directly included in the cage germanoxane synthesis is limited, this study demonstrates that other tetraalkylammonium cations can be introduced by cation exchange in both discrete and cross-linked states. Tetraethylammonium (TEA) of a discrete cage germanoxane was replaced with tetrabutylammonium (TBA) in an organic solvent, which provides another starting material. TEA and TBA cations in cross-linked networks formed by hydrosilylation reactions of dimethylvinylsilylated cage germanoxanes with various oligosiloxanes as linkers were exchanged with tetramethylammonium (TMA) cations. The variation in the pore volume, which depends on the type of introduced counter cations and oligosiloxane linkers, is verified. In terms of bottom-up synthesis of nanoporous materials from cage-type germanoxanes, the selection of both the counter cation and cross-linker is important to vary the porosity.

7.
Chem Sci ; 11(25): 6527-6531, 2020 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-34094118

RESUMO

Sialic acids are conspicuous structural components of the complex gangliosides that regulate cellular processes. Their importance in molecular recognition manifests itself in drug design (e.g. Tamiflu®) and continues to stimulate the development of effective chemical sialylation strategies to complement chemoenzymatic technologies. Stereodivergent approaches that enable the α- or ß-anomer to be generated at will are particularly powerful to attenuate hydrogen bond networks and interrogate function. Herein, we demonstrate that site-selective halogenation (F and Br) at C3 of the N-glycolyl units common to marine Neu2,6Glu epitopes enables pseudo-stereodivergent sialylation. α-Selective sialylation results from fluorination, whereas traceless bromine-guided sialylation generates the ß-adduct. This concept is validated in the synthesis of HLG-1 and Hp-s1 analogues.

8.
Molecules ; 24(16)2019 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-31426598

RESUMO

We previously reported on a polyhistidine peptide, His16 peptide, as a new cell-penetrating peptide. This peptide is anticipated to be a new carrier for drug delivery systems (DDSs) for targeting intracellular lysosomes because it can transport macromolecules (e.g., liposomes) into these organelles. In the present study, we examined the application of His16 peptide as a DDS carrier against lysosomal storage disease (LSD) cells. LSDs are metabolic disorders caused by loss of specific lysosomal enzymes. For the treatment of LSD cells, we devised a system designated organelle replacement therapy (ORT). ORT is a strategy for transporting exogenous lysosomes containing all kinds of lysosomal enzymes from normal cells into endogenous lysosomes in LSD cells using His16 peptide. To develop the ORT system, we prepared His16 peptide-modified healthy lysosomes (His16-Lyso) by insertion of a stearyl-His16 peptide into a hydrophobic region in the lysosomal membrane. His16-Lyso showed cellular uptake and localization to endogenous lysosomes in LSD cells. His16-Lyso also restored the proliferation of LSD cells, which otherwise showed slower proliferation than normal cells. These results suggested that His16-Lyso replenished deficient lysosomal enzymes in LSD cells. The results further suggest that His16-Lyso are promising candidates as a treatment tool for LSD cells and to establish a foundation for ORT.


Assuntos
Engenharia Celular/métodos , Peptídeos Penetradores de Células/metabolismo , Portadores de Fármacos , Histidina/metabolismo , Lisossomos/transplante , Transporte Biológico , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células , Peptídeos Penetradores de Células/síntese química , Doença de Fabry/patologia , Doença de Fabry/terapia , Fibroblastos/metabolismo , Fibroblastos/patologia , Expressão Gênica , Histidina/síntese química , Humanos , Interações Hidrofóbicas e Hidrofílicas , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Proteínas de Membrana Lisossomal/genética , Proteínas de Membrana Lisossomal/metabolismo , Lisossomos/química , Lisossomos/metabolismo , Modelos Biológicos , Terapia de Alvo Molecular/métodos , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Proteína Vermelha Fluorescente
9.
J Steroid Biochem Mol Biol ; 191: 105361, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30974191

RESUMO

Immunohistochemistry of human aldosterone synthase (CYP11B2) has revealed that most of aldosterone is autonomously produced in aldosterone-producing cell clusters (APCCs) beneath the capsule of adult adrenals rather than physiologically in the zona glomerulosa (ZG). APCCs have been occasionally found to harbor a somatic mutation of ion channel/pump genes, and number and size of APCCs increase with age until 50 years old. Herein, the objective of the study was to examine APCC development in 106 autopsied adrenals from 85 elderly individuals who died at ages from 50 to 103 years. We obtained the following results: (1) physiological CYP11B2 expression in ZG were attenuated in more elderly persons; (2) number and size of APCCs decreased with age; (3) detachment of APCC from the capsule appeared to occur occasionally over the wide range of the ages; and (4) incidental micro aldosterone-producing adenomas (APAs) and possible APCC-to-APA transitional lesions (pAATLs) were found primarily in samples from persons aged 50-60 years but not in samples from more elderly persons; pAATL was a putative designation based on our previous results indicating that it consisted of subcapsular APCC-like portion and inner APA-like portions. Thus, the formation of the CYP11B2-expressing lesions as well as thickening of the ZG in the adrenals were inversely correlated with age of death in the individuals aged over 50 years. Considering that autopsy samples were used in this study, inactive production of aldosterone regardless of autonomous or physiological manners may have survival advantages in individuals aged over 50 years.


Assuntos
Glândulas Suprarrenais/química , Citocromo P-450 CYP11B2/análise , Longevidade , Glândulas Suprarrenais/fisiologia , Glândulas Suprarrenais/ultraestrutura , Idoso , Idoso de 80 Anos ou mais , Envelhecimento , Aldosterona/metabolismo , Citocromo P-450 CYP11B2/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
10.
Chemistry ; 25(33): 7860-7865, 2019 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-30817031

RESUMO

Eight corners of a double-four ring cage-type germanoxane, containing a fluoride ion, were successfully silylated by the combination of chlorosilanes and silazanes. Three different silyl groups, trimethylsilyl, dimethylsilyl, and dimethylvinylsilyl, were attached on the corners of germanoxane cage. The solubility and reactivity of the cage modified with dimethylvinylsilyl groups were significantly increased, allowing for further reaction. Hydrosilylation reaction between dimethylvinylsilylated cage geramanoxanes and dimethylsilylated cage siloxanes afforded porous solids. Functionalization of the corners of germanoxanes with silyl groups should provide valuable building blocks in various functional materials.

11.
Angew Chem Int Ed Engl ; 58(16): 5321-5326, 2019 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-30802362

RESUMO

The first total synthesis of carthamin (3), a historic natural red pigment, has been achieved. The molecular structure was efficiently constructed by assembling two equivalents of the in situ generated lithiated monomers and triisopropyl orthoformate. This synthesis confirms the structure proposed in 1996.


Assuntos
Produtos Biológicos/síntese química , Chalcona/análogos & derivados , Glucosídeos/síntese química , Pigmentos Biológicos/síntese química , Produtos Biológicos/química , Chalcona/síntese química , Chalcona/química , Glucosídeos/química , Estrutura Molecular , Pigmentos Biológicos/química
12.
Angew Chem Int Ed Engl ; 58(12): 3814-3818, 2019 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-30681263

RESUMO

Sialic acids are ubiquitous components of mammalian cell membranes and key regulators of cellular recognition events. Located at the non-reducing termini of bioactive gangliosides, these essential building blocks are fused to the polysaccharide core via a characteristic α-linkage, and rarely occur in the monomeric form. Effective chemical strategies to enable α-sialylation are urgently required to construct well-defined tools for glycomics. To complement existing chemoenzymatic strategies, an α-selective process has been devised based on the site-selective introduction of fluorine at C3 (more than 20 examples, up to 90 % yield). Predicated on localized particle charge inversion (C-Hδ+ →C-Fδ- ), fluorine insertion simultaneously augments the anomeric effect, enhances electrophilicity at C2 and mitigates elimination. A stereochemical induction model is postulated that spans the SN continuum and validates the role of the C-F bond in orchestrating α-selectivity.


Assuntos
Flúor/química , Ácidos Siálicos/química , Gangliosídeos/química , Halogenação , Estereoisomerismo
13.
IJU Case Rep ; 2(5): 272-275, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32743435

RESUMO

INTRODUCTION: Pazopanib, a tyrosine kinase inhibitor, and nivolumab, an immune checkpoint inhibitor, are both considered to cause hepatotoxicity with different pathophysiology. We report a case in which a patient died of severe hepatotoxicity who was presumed to have been caused by the administration of nivolumab followed by pazopanib for metastatic renal cell carcinoma. CASE PRESENTATION: A 74-year-old male with metastatic renal cell carcinoma was treated with nivolumab as a third-line treatment. However, nivolumab was subsequently discontinued, as it caused severe thyroiditis. About 2 months after the final dose of nivolumab was administered, pazopanib was initiated as a fourth-line treatment. The patient suffered from lethal hepatic failure and died 18 days after the initiation of pazopanib treatment. An autopsy revealed that CD8-positive lymphocytes had infiltrated the thyroid gland and liver. CONCLUSION: The patient was considered to have died of severe hepatic failure due to the aggravation of mild nivolumab-induced immune-related hepatitis by pazopanib.

14.
Biochem Biophys Res Commun ; 501(3): 648-653, 2018 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-29746864

RESUMO

Cell-penetrating peptides (CPPs) can deliver payloads into cells by forming complexes with bioactive molecules via covalent or non-covalent bonds. Various CPPs have been applied in CPP-modified liposomes, and their effectiveness is highly regarded in liposomal drug delivery systems (DDSs). Previously, we have reported on the polyhistidine peptide (H16 peptide: HHHHHHHHHHHHHHHH-NH2) as a new CPP. The H16 peptide has a higher cell-penetrating capacity than well-known CPPs and delivers small molecules such as fluorescent dyes, bioactive peptides, and proteins into mammalian cells. However, it is not known whether the H16 peptide can deliver large cargos such as liposomes into cells. To assess the potential of the H16 peptide, in this study, we developed H16 peptide-modified liposomes (H16-Lipo) and evaluated their effectiveness in a liposomal DDS. The H16-Lipo was prepared by inserting a stearyl-H16 peptide into the hydrophobic region of a liposome. The H16-Lipo was internalized into human fibrosarcoma cells via multiple endocytosis pathways and localized to intracellular lysosomes. Based on this result, we used the H16-Lipo as a lysosome-targeting DDS. The H16-Lipo delivered alpha-galactosidase A (GLA), one of the lysosomal enzymes, to intracellular lysosomes and improved the proliferation of GLA-knockdown cells. These results suggest that the H16-Lipo is an effective drug carrier for lysosomal enzymes in a lysosome-targeting DDS. The loss of lysosomal enzymes has been known to induce metabolic disorders, called lysosomal storage diseases (LSDs). Our findings indicate that this combination of the H16 peptide and a liposome is a promising candidate as a DDS for the treatment of LSDs.


Assuntos
Histidina/metabolismo , Lipossomos/metabolismo , Lisossomos/metabolismo , alfa-Galactosidase/administração & dosagem , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos , Histidina/química , Humanos , Lipossomos/química , alfa-Galactosidase/farmacocinética
17.
Org Lett ; 19(4): 866-869, 2017 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-28165754

RESUMO

Toward the total synthesis of carthamin, a stereoselective approach to the C-glycosyl quinochalcone intermediate is reported via the desymmetrization of a pseudo-Cs-symmetric C-glycosyl cyclohexadienone.

18.
Urol Case Rep ; 3(6): 211-4, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26793556

RESUMO

A 56-year-old woman underwent laparoscopic right nephrectomy due to pyonephrosis associated with right ureteral stones. Moreover, the patient developed a brain stem hemorrhage and became bedridden. At the time of nephrectomy, a renal tumor, with a size of 24 × 24 × 20 mm, was observed in the left renal hilum; the tumor did not show contrast enhancement on computed tomography. After 3 years, the tumor gradually grew to a size of 45 × 35 × 34 mm, and therefore, laparoscopic non-clamping tumor enucleation was performed. Pathological examination confirmed a diagnosis of renal schwannoma.

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