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1.
Macromol Rapid Commun ; 45(12): e2400100, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38520318

RESUMO

Polymerization-induced self-assembly (PISA) has emerged as a scalable one-pot technique to prepare block copolymer (BCP) nanoparticles. Recently, a PISA process, that results in poly(l-lactide)-b-poly(ethylene glycol) BCP nanoparticles coined ring-opening polymerization (ROP)-induced crystallization-driven self-assembly (ROPI-CDSA), was developed. The resulting nanorods demonstrate a strong propensity for aggregation, resulting in the formation of 2D sheets and 3D networks. This article reports the synthesis of poly(N,N-dimethyl acrylamide)-b-poly(l)-lactide BCP nanoparticles by ROPI-CDSA, utilizing a two-step, one-pot approach. A dual-functionalized photoiniferter is first used for controlled radical polymerization of the acrylamido-based monomer, and the resulting polymer serves as a macroinitiator for organocatalyzed ROP to form the solvophobic polyester block. The resulting nanorods are highly stable and display anisotropy at higher molecular weights (>12k Da) and concentrations (>20% solids) than the previous report. This development expands the chemical scope of ROPI-CDSA BCPs and provides readily accessible nanorods made with biocompatible materials.


Assuntos
Nanotubos , Polimerização , Nanotubos/química , Anisotropia , Polímeros/química , Polímeros/síntese química , Poliésteres/química , Poliésteres/síntese química , Polietilenoglicóis/química , Processos Fotoquímicos , Estrutura Molecular , Tamanho da Partícula , Acrilamidas/química
2.
Med Princ Pract ; 27(5): 489-492, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29898455

RESUMO

OBJECTIVE: To present a case of lingual thyroid Hürthle cell carcinoma (HCC). CLINICAL PRESENTATION AND INTERVENTION: A 37-year-old female presented with dysphagia and recurrent haemorrhage. Histopathology was suggestive of HCC; the tumour was excised by the trans-glossal approach which provided adequate exposure and helped avert external scarring or mandibular osteotomy. Histopathology showed a tumour-positive right lateral resection margin. This prompted referral to nuclear medicine for radio-iodine ablation. CONCLUSION: Lingual thyroid cases should be followed up closely and fine-needle aspiration biopsy should be considered when in doubt.


Assuntos
Adenoma Oxífilo/patologia , Neoplasias da Glândula Tireoide/patologia , Adenoma Oxífilo/complicações , Adenoma Oxífilo/diagnóstico por imagem , Adenoma Oxífilo/tratamento farmacológico , Adulto , Feminino , Humanos , Hipotireoidismo/complicações , Hipotireoidismo/tratamento farmacológico , Neoplasias da Glândula Tireoide/complicações , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/tratamento farmacológico , Tiroxina/uso terapêutico
3.
Polymers (Basel) ; 16(6)2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38543357

RESUMO

Bio-based plastics made of food-safe compostable materials, such as thermoplastic starch (TPS), can be designed into films that have potential to replace many non-biodegradable single-use plastic (SUP) items. TPS film characteristics, such as elongation at break and tensile strength, are largely affected by the choice of the plasticizers used in formulation. Our work identifies the mechanical properties and the chemical structural differences between TPS films made with two different plasticizer mixtures that have not yet been compared alongside one another: deep eutectic solvent choline chloride/urea (1:2) (CC:U) and glycerol with an acetic acid catalyst (AA:G). Potato-based TPS samples were formed by mixing each plasticizer with a consistent amount of potato starch and distilled water with heat. After gelation formation, the viscous TPS mixture was centrifuged to degas and extruded. Films were dried at controlled room temperature. Characterization included the tensile testing of coupons according to ASTM (American Society of Testing and Materials) standard D638, attenuated total reflectance Fourier-transform infrared (ATR-FTIR) spectroscopy, X-ray diffraction (XRD), melting point (MP), and scanning electron microscopy (SEM). The AA:G films displayed significantly higher tensile strength (M = 2.04 ± 1.24 MPa) than the CC:U films (M = 0.18 ± 0.08 MPa); however, the CC:U films had higher elongation at break (M = 47.2 ± 3.6%) than the AA:G films (M = 31.1 ± 12.6%). This can be explained by the difference in functional groups, composition, and the degree of crystallinity evidenced by the FTIR, XRD, MP, and SEM results. Our findings suggest that potato-based TPS films with an AA:G plasticizer mixture hold promise for SUP applications that require more strength, while CC:U films may be more suited for wraps and bags that require flexibility. These innovations can aid to mitigate the environmental impact of harmful plastic waste.

4.
J Pathol Inform ; 14: 100322, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37457593

RESUMO

Introduction: A correct histopathological diagnosis is dependent on an array of technical variables. The quality and completeness of a histological section on a slide is extremely prudent for correct interpretation. However, this is mostly done manually and depends largely on the expertise of histotechnician. In this study, we analysed the application of digital image analysis for quality control of histological section as a proof-of-concept. Material and methods: Images of 1000 histological sections and their corresponding blocks were captured. Area of the section was measured from these digital images of tissue block (Digiblock) and slide (Digislide). The data was analysed to calculate DigislideQC score, dividing the area of tissue on the slide by the tissue area on the block and it was compared with the number of recuts done for incomplete section. Results: Digislide QC score ranged from 0.1 to 0.99. It showed an area under curve (AUC) of 98.8%. A cut-off value of 0.65 had a sensitivity of 99.6% and a specificity of 96.7%. Conclusion: Digiblock and Digislide images can provide information about quality of sections. DigislideQC score can correctly identify the slides which require recuts before it is sent for reporting and potentially reduce histopathologists' slide screening effort and ultimately turnaround time. These can be incorporated in routine histopathology workflows and lab information systems. This simple technology can also improve future digital pathology and telepathology workflows.

5.
Nat Commun ; 14(1): 464, 2023 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-36709333

RESUMO

Engineered outer membrane vesicles (OMVs) derived from Gram-negative bacteria are a promising technology for the creation of non-infectious, nanoparticle vaccines against diverse pathogens. However, antigen display on OMVs can be difficult to control and highly variable due to bottlenecks in protein expression and localization to the outer membrane of the host cell, especially for bulky and/or complex antigens. Here, we describe a universal approach for avidin-based vaccine antigen crosslinking (AvidVax) whereby biotinylated antigens are linked to the exterior of OMVs whose surfaces are remodeled with multiple copies of a synthetic antigen-binding protein (SNAP) comprised of an outer membrane scaffold protein fused to a biotin-binding protein. We show that SNAP-OMVs can be readily decorated with a molecularly diverse array of biotinylated subunit antigens, including globular and membrane proteins, glycans and glycoconjugates, haptens, lipids, and short peptides. When the resulting OMV formulations are injected in mice, strong antigen-specific antibody responses are observed that depend on the physical coupling between the antigen and SNAP-OMV delivery vehicle. Overall, these results demonstrate AvidVax as a modular platform that enables rapid and simplified assembly of antigen-studded OMVs for application as vaccines against pathogenic threats.


Assuntos
Membrana Externa Bacteriana , Vacinas , Animais , Camundongos , Antígenos , Proteínas de Membrana , Bactérias Gram-Negativas/metabolismo , Proteínas da Membrana Bacteriana Externa/metabolismo , Antígenos de Bactérias , Vacinas Bacterianas
6.
J Acoust Soc Am ; 131(4): 3051-68, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22501079

RESUMO

Studies on consonant perception under noise conditions typically describe the average consonant error as exponential in the Articulation Index (AI). While this AI formula nicely fits the average error over all consonants, it does not fit the error for any consonant at the utterance level. This study analyzes the error patterns of six stop consonants /p, t, k, b, d, g/ with four vowels (/α/, /ε/, /I/, /ae/), at the individual consonant (i.e., utterance) level. The findings include that the utterance error is essentially zero for signal to noise ratios (SNRs) at least -2 dB, for >78% of the stop consonant utterances. For these utterances, the error is essentially a step function in the SNR at the utterance's detection threshold. This binary error dependence is consistent with the audibility of a single binary defining acoustic feature, having zero error above the feature's detection threshold. Also 11% of the sounds have high error, defined as ≥ 20% for SNRs greater than or equal to -2 dB. A grand average across many such sounds, having a natural distribution in thresholds, results in the error being exponential in the AI measure, as observed. A detailed analysis of the variance from the AI error is provided along with a Bernoulli-trials analysis of the statistical significance.


Assuntos
Fonética , Acústica da Fala , Percepção da Fala/fisiologia , Sinais (Psicologia) , Humanos , Ruído , Mascaramento Perceptivo/fisiologia , Razão Sinal-Ruído , Espectrografia do Som , Testes de Articulação da Fala , Interface para o Reconhecimento da Fala
7.
ACS Omega ; 7(34): 29571-29586, 2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-36061655

RESUMO

This paper describes spectral, non-linear optical (NLO), and biological activity variation of pyrrole hydrazones as a result of structural variation. In order to study structure-property variation, pyrrole hydrazones (3A, 3B, and 3C) were synthesized in both solid and solution phases. The grinding solvent-free method becomes rapid, easy, convenient, useful, sustainable, and eco-friendly green synthesis as compared to the classical solution phase reactions. The structure of pyrrole hydrazones has been elucidated by microanalysis and quantum chemical calculations. The intense emission at λem 521 nm (3A and 3B) and 617 nm (3C) in the visible (green and orange) region with Stokes shifts at 195, 160, and 282 nm reveals that the studied compounds work as good photoluminescent materials. All compounds show strong n-π* and charge transfer (π-π*) transitions in the UV-vis region with high extinction coefficients. In the studied systems (3A, 3B, and 3C), the orbital overlap between σ(NH-O) → σ*(NH-O) is found due to intra-molecular charge transfer. The first hyperpolarizabilities were found to be 48.83 × 10-30 esu for 3B and 63.89 × 10-30 esu for 3C, showing variation with structure. Their high values indicate more suitability for NLO application. Incorporation and/or change in position of electron-withdrawing groups increase the ß0 values of 3B and 3C compared to 3A. The ß value also increases monotonically as the polarity of the solvents increases. The red shift in N-H and C=O stretching Fourier-transform infrared bonds is due to the formation of dimers. The synthesized 3A, 3B, and 3C show good antimicrobial activity and are predicted to be potential antibacterial and antifungal drugs. The 3B has more molar refractivity (122.16 esu) than 3A and 3C and correlates well with the calculated binding affinity and experimental antimicrobial data.

8.
Curr Mol Pharmacol ; 14(6): 1134-1145, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33573566

RESUMO

BACKGROUND: Breast cancer (BC) produces bone resorptive cytokines and growth factors that accelerate the development of osteoclasts (OCs), leading to osteolytic bone metastases. In the Long-term Odanacatib Fracture Trial (LOFT), the skeletal-metastasized breast cancer subjects who received odanacatib (ODN) had a delayed tumour progression and skeletal tumour burden as a result of anti-resorptive effects through inhibition of cathepsin K (CTSK). In this study, we explored the effect of ODN, a CTSK inhibitor, on the paracrine pro-osteoclast activity of breast cancer cells. METHODS: An immunohistochemistry study was performed to demonstrate CTSK and PTHrP expression in the samples of primary breast carcinoma. Expression of CTSK mRNA and protein was confirmed by the reverse transcription PCR and western blotting analysis in two human breast cancer cell lines, MDA-MB-231 and MCF-7 BC cell lines. Cells were incubated with sub-lethal amounts of ODN, and their conditioned supernatants were assessed for their capacity to differentiate PBMCs of healthy donors into osteoclast and its interference on bone-resorbing activities. We also measured the mRNA levels of major pro-osteoclast (pro-OC) factors in ODN-treated breast cancer cells and their secreted levels by semi-quantitative reverse transcription PCR and protein expression by immunoblotting. RESULTS: Different staining intensity was observed in samples containing PTHrP and CTSK in various histological grades of breast carcinoma. A significant positive relationship was found between CTSK expression and histological grade of BC and presence or absence of distant metastasis. The present study results also indicate that ODN has no effects on OCs number, however, ODN decreases the mRNA expression of secreted pro-OC factors such as PTHrP, CXCR-4, and TNF-α. Immunoblot indicates that ODN treatment decreased the protein expression of CTSK, IL-6, and IL-1ß, and thus lowered protein levels paralleled the defective phosphorylation of NF-κB. Moreover, there was a significant reduction in the level of growth factors such as IGF-1, PDGF, and TGFß expression at transcriptional level after ODN treatment as compared to control. CONCLUSION: ODN has shown to prevent osteolytic metastasis by interacting with the NF-κB pathway, inhibiting bone resorptive cytokines and growth factors. This effect can also be taken into account the delayed development of metastatic bone disease found in the long-term odanacatib fracture trial (LOFT) study.


Assuntos
Neoplasias da Mama , Osteoclastos , Compostos de Bifenilo/metabolismo , Compostos de Bifenilo/farmacologia , Neoplasias da Mama/metabolismo , Catepsina K/genética , Catepsina K/metabolismo , Feminino , Humanos
9.
Front Mol Neurosci ; 12: 316, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31920542

RESUMO

The stria vascularis (SV) generates the endocochlear potential (EP) in the inner ear and is necessary for proper hair cell mechanotransduction and hearing. While channels belonging to SV cell types are known to play crucial roles in EP generation, relatively little is known about gene regulatory networks that underlie the ability of the SV to generate and maintain the EP. Using single cell and single nucleus RNA-sequencing, we identify and validate known and rare cell populations in the SV. Furthermore, we establish a basis for understanding molecular mechanisms underlying SV function by identifying potential gene regulatory networks as well as druggable gene targets. Finally, we associate known deafness genes with adult SV cell types. This work establishes a basis for dissecting the genetic mechanisms underlying the role of the SV in hearing and will serve as a basis for designing therapeutic approaches to hearing loss related to SV dysfunction.

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