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1.
Chembiochem ; : e202400391, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38877657

RESUMO

Interactions between the tumor-associated carbohydrate antigens of Mucin 1 (MUC1) and the carbohydrate-binding proteins, lectins, often lead to the creation of a pro-tumor microenvironment favoring tumor initiation, progression, metastasis, and immune evasion. Macrophage galactose binding lectin (MGL) is a C-type lectin receptor found on antigen-presenting cells that facilitates the uptake of carbohydrate antigens for antigen presentation, modulating the immune response homeostasis, autoimmunity, and cancer. Considering the crucial role of tumor-associated forms of MUC1 and MGL in tumor immunology, a thorough understanding of their binding interaction is essential for it to be exploited for cancer vaccine strategies. The synthesis of MUC1 glycopeptide models carrying a single or multiple Tn and/or sialyl-Tn antigen(s) is described. A novel approach for the sialyl-Tn threonine building block suitable for the solid phase peptide synthesis was developed. The thermodynamic profile of the binding interaction between the human MGL and MUC1 glycopeptide models was analyzed using isothermal titration calorimetry. The measured dissociation constants for the sialyl-Tn-bearing peptide epitopes were consistently lower compared to the Tn antigen and ranged from 10 µM for mono- to 100 nM for triglycosylated MUC1 peptide, respectively. All studied interactions, regardless of the glycan's site of attachment or density, exhibited enthalpy-driven thermodynamics.

2.
J Neuroophthalmol ; 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38175728

RESUMO

BACKGROUND: Multiple myeloma (MM) is a malignant disorder of plasma cells that results in tumor cells replacing the bone marrow. In extramedullary MM (EMM), however, tumor cells proliferate outside the bone marrow. EMM may produce ophthalmoplegia through direct invasion of the superior orbital fissure, cavernous sinus, and/or sphenoidal sinus. Several mechanisms have been proposed including cranial nerve palsies, direct infiltration of bone, extraocular muscle metastasis, myelomatous meningitis, and parenchymal or paraneoplastic effects. METHODS: We retrospectively reviewed the medical records of 7 patients at MD Anderson Cancer Center who suffered from ophthalmoplegia secondary to extramedullary MM between 2019 and 2021. We collected information regarding the symptoms, signs, radiographic and laboratory findings, management, complications, and prognosis of these patients throughout their disease course. RESULTS: Skull base MRI revealed 4 patients with ophthalmoplegias secondary to superior orbital fissure invasion, 2 patients with ophthalmoplegias secondary to cavernous sinus invasion, and 1 patient with ophthalmoplegia secondary to sphenoid sinus invasion. CONCLUSIONS: This is a case series describing 7 patients with ophthalmoplegias secondary to EMM. Our article is unique because of the size of the included cohort, which is large when compared with most English language publications detailing such ophthalmoplegias.

3.
Clin Infect Dis ; 77(7): 976-986, 2023 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-37235212

RESUMO

BACKGROUND: Patients without human immunodeficiency virus (HIV) are increasingly recognized as being at risk for cryptococcosis. Knowledge of characteristics of cryptococcosis in these patients remains incomplete. METHODS: We conducted a retrospective study of cryptococcosis in 46 Australian and New Zealand hospitals to compare its frequency in patients with and without HIV and describe its characteristics in patients without HIV. Patients with cryptococcosis between January 2015 and December 2019 were included. RESULTS: Of 475 patients with cryptococcosis, 90% were without HIV (426 of 475) with marked predominance in both Cryptococcus neoformans (88.7%) and Cryptococcus gattii cases (94.3%). Most patients without HIV (60.8%) had a known immunocompromising condition: cancer (n = 91), organ transplantation (n = 81), or other immunocompromising condition (n = 97). Cryptococcosis presented as incidental imaging findings in 16.4% of patients (70 of 426). The serum cryptococcal antigen test was positive in 85.1% of tested patients (319 of 375); high titers independently predicted risk of central nervous system involvement. Lumbar puncture was performed in 167 patients to screen for asymptomatic meningitis, with a positivity rate of 13.2% where meningitis could have been predicted by a high serum cryptococcal antigen titer and/or fungemia in 95% of evaluable cases. One-year all-cause mortality was 20.9% in patients without HIV and 21.7% in patients with HIV (P = .89). CONCLUSIONS: Ninety percent of cryptococcosis cases occurred in patients without HIV (89% and 94% for C. neoformans and C. gattii, respectively). Emerging patient risk groups were evident. A high level of awareness is warranted to diagnose cryptococcosis in patients without HIV.


Assuntos
Criptococose , Cryptococcus gattii , Cryptococcus neoformans , Infecções por HIV , Meningite , Humanos , HIV , Estudos Retrospectivos , Nova Zelândia/epidemiologia , Austrália/epidemiologia , Criptococose/diagnóstico , Criptococose/epidemiologia , Hospitais , Antígenos de Fungos , Infecções por HIV/complicações , Infecções por HIV/epidemiologia
4.
Sex Health ; 20(6): 597-598, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37939677

RESUMO

Women living with HIV in regional Victoria face barriers accessing care. We evaluated the care cascade and outreach nurse support required for women attending our service between 2005 and 2020. A total of 33 women attended; 97% (32/33) were on antiretroviral therapy; 67% (22/33) retained in care, 27% (9/33) transferred and 6% (2/33) lost to follow up. Of women retained in care, 95% (21/22) were on antiretroviral therapy and 91% (20/22) had virological suppression. A total of 91% (30/33) required outreach nurse care (median care episodes 100/woman; IQR 44-179) - most frequently (87%; 26/30) liaising with pharmacies and prescribers. Outreach nurses are critical in achieving UNAIDS targets for women in western Victoria.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Humanos , Feminino , Infecções por HIV/tratamento farmacológico , Fármacos Anti-HIV/uso terapêutico
5.
Angew Chem Int Ed Engl ; 61(52): e202213739, 2022 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-36318472

RESUMO

Carboxylic acids are attractive building blocks for synthetic chemistry because they are chemically stable, abundant, and commercially available with substantial structural diversity. The process of combining two carboxylic acids to furnish a ketone is termed ketonization. This is a potentially valuable transformation that has been underutilized in organic synthesis due to the harsh reaction conditions generally required and the lack of selectivity obtained when coupling two distinct carboxylic acids. We report herein a metallaphotoredox strategy that selectively generates unsymmetrical ketones via cross-ketonization of two structurally dissimilar carboxylic acids. Cross-selectivity is achieved by exploiting divergent reactivity of differentially substituted acids towards critical one- and two-electron processes in the proposed coupling mechanism. This method is broadly applicable to a variety of functionalized carboxylic acids. It can also be applied to acids of similar steric profile by exploiting differences in their relative rates of decarboxylation.


Assuntos
Ácidos Carboxílicos , Cetonas , Ácidos Carboxílicos/química , Estrutura Molecular , Oxirredução , Catálise , Cetonas/química
6.
Angew Chem Int Ed Engl ; 61(1): e202112288, 2022 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-34739741

RESUMO

A palladium-catalyzed strategy is presented to synthesize unsymmetrically linked heterocycles within stereoselective tetrasubstituted olefins. This reaction is proposed to occur via a vinyl-PdII intermediate capable of initiating the cyclization of various alkyne-tethered nucleophiles. Products are formed in up to 96 % yield and excellent stereoselectivities are obtained using low catalyst loadings. This transformation was scalable up to 1 mmol and mechanistic studies suggest a syn-carbopalladation of the carbamoyl chloride followed by PdII -catalyzed cyclization of alkyne-tethered nucleophiles.

7.
Angew Chem Int Ed Engl ; 60(37): 20231-20236, 2021 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-34240542

RESUMO

An enantioselective consecutive cyclization/coupling process, catalyzed by palladium is reported. Stereoinduction arises from an enantioselective carbopalladation, generating an intermediate which promotes a nucleopalladation step. The dual cyclization sequence was compatible with a variety of alkyne-tethered oxygen- and nitrogen-centered nucleophiles, and a variety of alkenyl-tethered aryl iodides, to forge numerous bisheterocycles in good yields and high regio- and enantioselectivities.

8.
Angew Chem Int Ed Engl ; 60(34): 18478-18483, 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34157191

RESUMO

Hexafluoroisopropanol (HFIP) was employed as an additive for the generation of 3-(chloromethylene)oxindoles via the chloroacylation of alkyne-tethered carbamoyl chlorides. This reaction avoids the use of a metal catalyst and accesses products in high yields and stereoselectivities. Additionally, this reaction is scalable and proved amenable to a series of product derivatizations, including the synthesis of nintedanib. The reactivity of alkene-tethered carbamoyl chlorides with hexafluoroisopropanol (HFIP) was harnessed towards the synthesis of 2-quinolinones.

9.
J Am Chem Soc ; 142(20): 9510-9517, 2020 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-32337994

RESUMO

An asymmetric hydroarylative cyclization of enynes involving a C-H bond cleavage is reported. The cobalt-catalyzed cascade generates three new bonds in an atom-economical fashion. The products were obtained in excellent yields and excellent enantioselectivities as single diastereo- and regioisomers. Preliminary mechanistic studies indicate that the reaction shows no intermolecular C-H crossover. This work highlights the potential of cobalt catalysis in C-H bond functionalization and enantioselective domino reactivity.

10.
Clin Exp Allergy ; 50(8): 886-893, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32512632

RESUMO

Allergy to insects of the family Tabanidae (order Diptera), commonly called horseflies or deerflies, is anecdotally common, although the published literature is limited to case reports and small case series. This review summarizes the available literature, in which there is enormous variability in clinical detail, identification of species or even genus, and means and thoroughness of assessment of sensitization. The clinical utility of in vivo and in vitro assays remains unclear. Investigation and management of patients reporting anaphylaxis to suspected bites must therefore be pragmatic, by considering other insects (eg Hymenoptera), provision of a written action plan and self-injectable adrenaline if appropriate, and advice on avoidance.


Assuntos
Alérgenos/imunologia , Anafilaxia/imunologia , Dípteros/imunologia , Mordeduras e Picadas de Insetos/imunologia , Proteínas de Insetos/imunologia , Anafilaxia/diagnóstico , Anafilaxia/prevenção & controle , Animais , Antialérgicos/administração & dosagem , Epinefrina/administração & dosagem , Humanos , Injeções , Mordeduras e Picadas de Insetos/diagnóstico , Mordeduras e Picadas de Insetos/prevenção & controle
11.
J Allergy Clin Immunol ; 143(4): 1482-1495, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30170123

RESUMO

BACKGROUND: Caspase activation and recruitment domain 11 (CARD11) encodes a scaffold protein in lymphocytes that links antigen receptor engagement with downstream signaling to nuclear factor κB, c-Jun N-terminal kinase, and mechanistic target of rapamycin complex 1. Germline CARD11 mutations cause several distinct primary immune disorders in human subjects, including severe combined immune deficiency (biallelic null mutations), B-cell expansion with nuclear factor κB and T-cell anergy (heterozygous, gain-of-function mutations), and severe atopic disease (loss-of-function, heterozygous, dominant interfering mutations), which has focused attention on CARD11 mutations discovered by using whole-exome sequencing. OBJECTIVES: We sought to determine the molecular actions of an extended allelic series of CARD11 and to characterize the expanding range of clinical phenotypes associated with heterozygous CARD11 loss-of-function alleles. METHODS: Cell transfections and primary T-cell assays were used to evaluate signaling and function of CARD11 variants. RESULTS: Here we report on an expanded cohort of patients harboring novel heterozygous CARD11 mutations that extend beyond atopy to include other immunologic phenotypes not previously associated with CARD11 mutations. In addition to (and sometimes excluding) severe atopy, heterozygous missense and indel mutations in CARD11 presented with immunologic phenotypes similar to those observed in signal transducer and activator of transcription 3 loss of function, dedicator of cytokinesis 8 deficiency, common variable immunodeficiency, neutropenia, and immune dysregulation, polyendocrinopathy, enteropathy, X-linked-like syndrome. Pathogenic variants exhibited dominant negative activity and were largely confined to the CARD or coiled-coil domains of the CARD11 protein. CONCLUSION: These results illuminate a broader phenotypic spectrum associated with CARD11 mutations in human subjects and underscore the need for functional studies to demonstrate that rare gene variants encountered in expected and unexpected phenotypes must nonetheless be validated for pathogenic activity.


Assuntos
Proteínas Adaptadoras de Sinalização CARD/genética , Proteínas Adaptadoras de Sinalização CARD/imunologia , Guanilato Ciclase/genética , Guanilato Ciclase/imunologia , Doenças do Sistema Imunitário/genética , Doenças do Sistema Imunitário/imunologia , Adulto , Feminino , Humanos , Masculino , Mutação , Fenótipo
12.
Angew Chem Int Ed Engl ; 59(38): 16409-16413, 2020 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-32524694

RESUMO

We report a cobalt-catalyzed hydroacylation of 1,6-enynes with exogenous aldehydes in a domino sequence to construct enantioenriched ketones. The products were obtained in good yields with excellent regio-, diastereo-, and enantioselectivity. Furthermore, the chiral products served as valuable precursors to access complex spirocyclic scaffolds with three contiguous stereocenters. The asymmetric hydroacylation process exhibited no C-H crossover and no KIE, thus indicating that the C-H bond cleavage was not involved in the turnover-limiting step.

14.
Angew Chem Int Ed Engl ; 57(42): 13927-13930, 2018 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-30160825

RESUMO

An enantioselective copper-catalyzed intramolecular borylacylation is reported. The reaction proceeds through an initial enantioselective borylcupration of the styrene, followed by a nucleophilic attack on the tethered carbamoyl chloride. The products, chiral borylated 3,3-disubstituted oxindoles, were generated in excellent yields and enantioselectivities. The versatile carbon-boron bond provides a platform for a wide array of diversification.

19.
Chemistry ; 21(32): 11325-9, 2015 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-26177931

RESUMO

The remarkably high intracellular concentration of reducing agents is an excellent endogenous stimulus for designing nanocarriers programmed for intracellular delivery of therapeutic agents. However, despite their excellent biodegradability profiles, aliphatic polyesters that are fully degradable in response to the intracellular reducing environment are rare. Herein, a reduction-responsive drug delivery nanocarrier derived from a linear polyester bearing disulfide bonds is reported. The reduction-responsive polyester is synthesized via a convenient polycondensation process. After conjugation of terminal carboxylic acid groups of polyester to polyethylene glycol (PEG), the resulting polymer self-assembles into nanoparticles that are capable of encapsulating dye and anticancer drug molecules. The reduction-responsive nanoparticles display a fast payload release rate in response to the intracellular reducing environment, which translates into superior anticancer activity towards PC-3 cells.


Assuntos
Antineoplásicos/química , Polietilenoglicóis/química , Polímeros/química , Antineoplásicos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Humanos , Masculino , Nanopartículas/química , Poliésteres/química , Neoplasias da Próstata/tratamento farmacológico
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