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1.
Angew Chem Int Ed Engl ; 63(15): e202400838, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38372011

RESUMO

Developing artificial enzymes based on organic molecules or polymers for reactive oxygen species (ROS)-related catalysis has broad applicability. Herein, inspired by porphyrin-based heme mimics, we report the synthesis of polyphthalocyanine-based conjugated polymers (Fe-PPc-AE) as a new porphyrin-evolving structure to serve as efficient and versatile artificial enzymes for augmented reactive oxygen catalysis. Owing to the structural advantages, such as enhanced π-conjugation networks and π-electron delocalization, promoted electron transfer, and unique Fe-N coordination centers, Fe-PPc-AE showed more efficient ROS-production activity in terms of Vmax and turnover numbers as compared with porphyrin-based conjugated polymers (Fe-PPor-AE), which also surpassed reported state-of-the-art artificial enzymes in their activity. More interestingly, by changing the reaction medium and substrates, Fe-PPc-AE also revealed significantly improved activity and environmental adaptivity in many other ROS-related biocatalytic processes, validating the potential of Fe-PPc-AE to replace conventional (poly)porphyrin-based heme mimics for ROS-related catalysis, biosensors, or biotherapeutics. It is suggested that this study will offer essential guidance for designing artificial enzymes based on organic molecules or polymers.


Assuntos
Heme , Porfirinas , Heme/química , Oxigênio/química , Espécies Reativas de Oxigênio , Porfirinas/química , Catálise , Polímeros
2.
Br J Ophthalmol ; 107(12): 1914-1919, 2023 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-36229179

RESUMO

BACKGROUND: We report visual outcomes and ocular complications in patients with lacrimal gland carcinoma who had eye-sparing surgery followed by radiotherapy. METHODS: This review included consecutive patients with lacrimal gland carcinoma who underwent eye-sparing surgery and adjuvant radiotherapy or concurrent chemoradiation therapy between 2007 and 2018. Clinical data, including details of ophthalmological examinations and radiation treatment were reviewed. RESULTS: The study included 23 patients, 15 males and 8 females, with median age 51 years. Twenty patients (87%) received intensity-modulated proton therapy; 3 (13%) received intensity-modulated radiotherapy. Nineteen patients (83%) received concurrent chemotherapy. After a median follow-up time of 37 months (range: 8-83), 13 patients (57%) had best-corrected visual acuity 20/40 or better, 3 (13%) had moderate vision loss (between 20/40 and 20/200) and 7 (30%) had severe vision loss (20/200 or worse). The most common ocular complications were dry eye disease (21 patients; 91%), radiation retinopathy (16; 70%) and cataract progression (11; 49%). Tumour crossing the orbital midline (p=0.014) and Hispanic ethnicity (p=0.014) were associated with increased risk of severe vision loss. The risk of radiation retinopathy was significantly different among the three racial groups; Hispanic patients (n=3) had the highest rate of retinopathy (p<0.001). Tumour size, initial T category and total prescribed radiation dose were not significantly associated with severe vision loss. CONCLUSION: Eye-sparing surgery followed by adjuvant radiotherapy in patients with lacrimal gland carcinoma has a reasonable overall visual prognosis. Patients with tumours crossing the orbital midline and Hispanic patients have a higher risk of severe vision loss.


Assuntos
Carcinoma , Síndromes do Olho Seco , Neoplasias Oculares , Aparelho Lacrimal , Doenças Retinianas , Masculino , Feminino , Humanos , Pessoa de Meia-Idade , Radioterapia Adjuvante/efeitos adversos , Aparelho Lacrimal/patologia , Aparelho Lacrimal/cirurgia , Neoplasias Oculares/radioterapia , Neoplasias Oculares/patologia , Síndromes do Olho Seco/patologia , Doenças Retinianas/patologia , Estudos Retrospectivos
3.
Retina ; 42(11): 2169-2175, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-35982514

RESUMO

PURPOSE: To describe perivascular flower-bud-like lesions (PFBLs) as novel characteristics of vitreoretinal lymphoma on en face optical coherence tomography (OCT) angiography. METHODS: A retrospective chart review was performed on 23 consecutive patients (35 eyes), who had biopsy-proven vitreoretinal lymphoma between January 2018 and March 2021. En face OCT angiography images were analyzed before and after intervention. PFBLs were initially identified on midretinal slabs of en face OCT angiography, and were further characterized by other imaging modalities. RESULTS: Perivascular flower-bud-like lesions were detected in 12 eyes (34.3%) of 8 patients, of which 8 eyes had best-corrected visual acuity of 20/40 or better. In 10 of the 12 eyes, PFBLs were detected within 6 months of symptom onset. On en face OCT angiography, PFBLs presented as punctate points or confluent bands surrounding retinal vessels, with arterial and venous involvement. In 4 of the 12 eyes, arteries were mainly affected. On OCT B-scans, PFBLs commonly appeared as hyperreflective full-thickness intraretinal lesions that colocalized with subretinal pigment epithelium deposits (3 eyes, 25%) and retinal pigment epithelium irregularities (4 eyes, 33.3%). However, PFBLs could not always be identified on other imaging modalities such as fundus photographs and fundus fluorescein angiography. In all eyes with follow-up, PFBLs attenuated or resolved months after receiving chemotherapy or diagnostic vitrectomy. CONCLUSION: PFBLs are characteristic imaging findings of vitreoretinal lymphoma and may facilitate an early diagnosis of vitreoretinal lymphoma, which would in turn lead to more timely and effective treatment.


Assuntos
Neoplasias Oculares , Linfoma , Neoplasias da Retina , Humanos , Tomografia de Coerência Óptica/métodos , Neoplasias da Retina/diagnóstico , Neoplasias da Retina/patologia , Estudos Retrospectivos , Corpo Vítreo/diagnóstico por imagem , Corpo Vítreo/patologia , Angiofluoresceinografia/métodos , Linfoma/patologia , Flores , Fundo de Olho
4.
Appl Environ Microbiol ; 87(18): e0092321, 2021 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-34232707

RESUMO

Cotinine is a stable toxic contaminant, produced as a by-product of smoking. It is of emerging concern due to its global distribution in aquatic environments. Microorganisms have the potential to degrade cotinine; however, the genetic mechanisms of this process are unknown. Nocardioides sp. strain JQ2195 is a pure-culture strain that has been reported to degrade cotinine at micropollutant concentrations. This strain utilizes cotinine as its sole carbon and nitrogen source. In this study, a 50-kb gene cluster (designated cot), involved in cotinine degradation, was predicted based on genomic and transcriptomic analyses. A novel three-component cotinine hydroxylase gene (designated cotA1A2A3), which initiated cotinine catabolism, was identified and characterized. CotA from Shinella sp. strain HZN7 was heterologously expressed and purified and was shown to convert cotinine into 6-hydroxycotinine. H218O-labeling and electrospray ionization-mass spectrometry (ESI-MS) analysis confirmed that the hydroxyl group incorporated into 6-hydroxycotinine was derived from water. This study provides new molecular insights into the microbial metabolism of heterocyclic chemical pollutants. IMPORTANCE In the human body, cotinine is the major metabolite of nicotine, and 10 to 15% of generated cotinine is excreted in urine. Cotinine is a structural analogue of nicotine and is much more stable than nicotine. Increased tobacco consumption has led to high environmental concentrations of cotinine, which may have detrimental effects on aquatic ecosystems and human health. Nocardioides sp. strain JQ2195 is a unique cotinine-degrading bacterium. However, the underlying genetic and biochemical foundations of cotinine degradation are still unknown. In this study, a 50-kb gene cluster (designated cot) was identified by genomic and transcriptomic analyses as being involved in the degradation of cotinine. A novel three-component cotinine hydroxylase gene (designated cotA1A2A3) catalyzed cotinine to 6-hydroxy-cotinine. This study provides new molecular insights into the microbial degradation and enzymatic transformation of cotinine.


Assuntos
Proteínas de Bactérias/metabolismo , Cotinina/metabolismo , Oxigenases de Função Mista/metabolismo , Nocardioides/metabolismo , Poluentes Químicos da Água/metabolismo , Proteínas de Bactérias/genética , Biodegradação Ambiental , Biotransformação , Cotinina/análogos & derivados , Genoma Bacteriano , Oxigenases de Função Mista/genética , Nocardioides/genética , Transcriptoma , Águas Residuárias/microbiologia
5.
Adv Mater ; 33(29): e2101095, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34096109

RESUMO

The diversity, complexity, and heterogeneity of malignant tumor seriously undermine the efficiency of mono-modal treatment. Recently, multi-modal therapeutics with enhanced antitumor efficiencies have attracted increasing attention. However, designing a nanotherapeutic platform with uniform morphology in nanoscale that integrates with efficient chem-/sono-/photo-trimodal tumor therapies is still a great challenge. Here, new and facile Pd-single-atom coordinated porphyrin-based polymeric networks as biocatalysts, namely, Pd-Pta/Por, for chem-/sono-/photo-trimodal tumor therapies are designed. The atomic morphology and chemical structure analysis prove that the biocatalyst consists of atomic Pd-N coordination networks with a Pd-N2 -Cl2 catalytic center. The characterization of peroxidase-like catalytic activities displays that the Pd-Pta/Por can generate abundant •OH radicals for chemodynamic therapies. The ultrasound irradiation or laser excitation can significantly boost the catalytic production of 1 O2 by the porphyrin-based sono-/photosensitizers to achieve combined sono-/photodynamic therapies. The superior catalytic production of •OH is further verified by density functional theory calculation. Finally, the corresponding in vitro and in vivo experiments have demonstrated their synergistic chem-/sono-/photo-trimodal antitumor efficacies. It is believed that this study provides new promising single-atom-coordinated polymeric networks with highly efficient biocatalytic sites and synergistic trimodal therapeutic effects, which may inspire many new findings in reactive oxygen species-related biological applications across broad therapeutics and biomedical fields.


Assuntos
Fármacos Fotossensibilizantes , Células HeLa , Humanos , Fotoquimioterapia , Porfirinas , Espécies Reativas de Oxigênio
6.
Anim Sci J ; 92(1): e13541, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33728713

RESUMO

Toll-like receptors (TLRs) participate in regulation of adaptive immune responses, and lymph nodes play key roles in the initiation of immune responses. There is a tolerance to the allogenic fetus during pregnancy, but it is unclear that expression of TLR signaling is in ovine lymph node during early pregnancy. In this study, lymph nodes were sampled from day 16 of nonpregnant ewes and days 13, 16, and 25 of pregnant ewes, and the expressions of TLR family (TLR2, TLR3, TLR4, TLR5 and TLR9), adaptor proteins, including myeloid differentiation primary-response protein 88 (MyD88), tumor necrosis factor receptor associated factor 6 (TRAF6), and interleukin-1-receptor-associated kinase 1 (IRAK1), were analyzed through real-time quantitative polymerase chain reaction, Western blot, and immunohistochemistry analysis. The results showed that mRNA and protein levels of TLR2, TLR3, TLR4, TRAF6, and MyD88 were upregulated in the maternal lymph node, but TLR5, TLR9, and IRAK1 were downregulated during early pregnancy. In addition, MyD88 protein was located in the subcapsular sinus and lymph sinuses. Therefore, it is suggested that early pregnancy induces changes in TLR signaling in maternal lymph node, which may be involved in regulation of maternal immune responses in sheep.


Assuntos
Linfonodos/imunologia , Prenhez/imunologia , Ovinos/imunologia , Transdução de Sinais/imunologia , Receptores Toll-Like/imunologia , Animais , Regulação para Baixo/genética , Regulação para Baixo/imunologia , Feminino , Feto/imunologia , Expressão Gênica , Fator 88 de Diferenciação Mieloide/imunologia , Fator 88 de Diferenciação Mieloide/metabolismo , Gravidez , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fator 6 Associado a Receptor de TNF/imunologia , Fator 6 Associado a Receptor de TNF/metabolismo , Receptores Toll-Like/metabolismo , Regulação para Cima/genética , Regulação para Cima/imunologia
7.
Ophthalmic Plast Reconstr Surg ; 37(3): e97-e100, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33079761

RESUMO

Orbital compartment syndrome is an ophthalmologic emergency that requires timely surgical intervention. The authors present a rare case of orbital compartment syndrome in a 30-year-old male injured by forceful entry of air-gasoline mixture into the orbit, secondary to inadvertent firing of the piston from running mechanical diagnostics on an automobile internal combustion engine. Orbital CT revealed extensive orbital emphysema with both pre- and postseptal involvement and diffuse chemical cellulitis. Serial exams revealed rapid deterioration of vision with elevated intraocular pressure and development of eyelid, corneal, and orbital edema; a relative afferent pupillary defect and optic nerve hypoperfusion. He was started on intravenous steroids and underwent an emergent lateral canthotomy with cantholysis, which temporarily reduced the intraocular pressure. However, a second rapid increase in soft tissue swelling resulted in another episode of ocular hypertension and compressive optic neuropathy, requiring emergent orbital bony decompression, which was followed by decreased intraocular and orbital pressure. The patient later developed progressive corneal opacification indicating delayed chemical injury. This was managed with a 10-day course of aggressive topical and systemic antiinflammatory agents with significant improvement in visual acuity. At last follow up, the vision was 20/30 and the corneal and eyelid edema had cleared.


Assuntos
Traumatismos por Explosões , Síndromes Compartimentais , Doenças Orbitárias , Adulto , Traumatismos por Explosões/etiologia , Síndromes Compartimentais/diagnóstico , Síndromes Compartimentais/etiologia , Síndromes Compartimentais/cirurgia , Descompressão Cirúrgica , Gasolina , Humanos , Masculino , Órbita/cirurgia , Doenças Orbitárias/cirurgia
8.
Pharm Res ; 35(4): 78, 2018 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-29492680

RESUMO

PURPOSE: Studies were conducted to investigate dilute solutions of the monoclonal antibody (mAb) bevacizumab, mAb fragment ranibizumab and fusion protein aflibercept, develop common procedures for formulation of low concentration mAbs and identify a stabilizing formulation for anti-VEGF mAbs for use in in vitro permeation studies. METHODS: Excipient substitutions were screened. The most stabilizing formulation was chosen. Standard dilutions of bevacizumab, ranibizumab and aflibercept were prepared in PBS, manufacturer's formulation, and the new formulation. Analysis was by SE-HPLC and ELISA. Stability, disaggregation and pre-exposure tests were studied. RESULTS: When Avastin, Lucentis and Eylea are diluted in PBS or manufacturer's formulation, there is a 40-50% loss of monomer concentration and drug activity. A formulation containing 0.3% NaCl, 7.5% trehalose, 10 mM arginine and 0.04% Tween 80 at a pH of 6.78 stabilized the mAbs and minimized the drug loss. The formulation also disaggregates mAb aggregation while preserving the activity. Degassing the formulation increases recovery. CONCLUSIONS: We developed a novel formulation that significantly stabilizes mAbs under unfavorable conditions such as low concentration or body temperature. The formulation allows for tissue permeation experimentation. The formulation also exhibits a disaggregating effect on mAbs, which can be applied to the manufacture/packaging of mAbs and bioassay reagents.


Assuntos
Inibidores da Angiogênese/química , Produtos Biológicos/química , Composição de Medicamentos/métodos , Excipientes/química , Bevacizumab/química , Bioensaio/métodos , Estabilidade de Medicamentos , Agregados Proteicos , Ranibizumab/química , Receptores de Fatores de Crescimento do Endotélio Vascular/química , Proteínas Recombinantes de Fusão/química , Soluções , Temperatura
9.
Pharm Res ; 35(6): 110, 2018 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-29600470

RESUMO

PURPOSE: Permeation studies, with near infrared (NIR) light and anti-aggregation antibody formulation, were used to investigate the in vitro permeation of bevacizumab, ranibizumab and aflibercept through human sclera. METHODS: A vertical, spherical Franz cell diffusion apparatus was used for this scleral tissue permeation model. A photokinetic ocular drug delivery (PODD) testing device accommodated the placement of NIR LEDs above the donor chambers. An adjustable LED driver/square wave generator provided electrical energy with a variable pulse rate and pulse width modulation (duty cycle). RESULTS: Exposure to non-thermal NIR light had no effect on mAbs with regard to monomer concentration or antibody binding potential, as determined by SE-HPLC and ELISA. The optimal LED wavelength was found to be 950 nm. Duty cycle power of 5% vs 20% showed no difference in permeation. When compared to controls, the combination of non-aggregating antibody formulation and NIR illumination provided an average transscleral drug flux enhancement factor of 3X. CONCLUSION: Narrow wavelength incoherent (non-laser) light from an NIR LED source is not harmful to mAbs and can be used to enhance drug permeation through scleral tissue. The topical formulation, combined with pulsed NIR light irradiation, significantly improved scleral permeation of three anti-VEGF antibody drugs.


Assuntos
Inibidores da Angiogênese/farmacocinética , Raios Infravermelhos , Esclera/metabolismo , Administração Oftálmica , Inibidores da Angiogênese/administração & dosagem , Bevacizumab/administração & dosagem , Bevacizumab/farmacocinética , Humanos , Degeneração Macular/tratamento farmacológico , Degeneração Macular/patologia , Permeabilidade/efeitos da radiação , Ranibizumab/administração & dosagem , Ranibizumab/farmacocinética , Receptores de Fatores de Crescimento do Endotélio Vascular/administração & dosagem , Proteínas Recombinantes de Fusão/administração & dosagem , Proteínas Recombinantes de Fusão/farmacocinética , Esclera/efeitos da radiação , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/metabolismo
10.
Appl Opt ; 55(10): 2741-7, 2016 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-27139680

RESUMO

The electron temperature was evaluated using the line-to-continuum ratio method, and whether the plasma was close to the local thermodynamic equilibrium (LTE) state was investigated in detail. The results showed that approximately 5 µs after the plasma formed, the changes in the electron and excitation temperatures, which were determined using a Boltzmann plot, overlapped in the 15% error range, which indicated that the LTE state was reached. The recombination of electrons and ions and the free electron expansion process led to the deviation from the LTE state. The plasma's expansion rate slowed over time, and when the expansion time was close to the ionization equilibrium time, the LTE state was almost reached. The McWhirter criterion was adopted to calculate the threshold electron density for different species, and the results showed that experimental electron density was greater than the threshold electron density, which meant that the LTE state may have existed. However, for the nonmetal element N, the threshold electron density was greater than the value experimental value approximately 0.8 µs after the plasma formed, which meant that LTE state did not exist for N.

11.
Eur J Ophthalmol ; 24(6): 911-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24846625

RESUMO

PURPOSE: To investigate the role of vitrectomy in the diagnosis of intraocular lymphoma by evaluating the effects of aspiration pressure and cut rate on cell viability and diagnostic yield. METHODS: Cells of the human Burkitt lymphoma cell line Namalwa were processed by 20-G vitrectomy under 2 different aspiration pressures and at different cut rates. Some samples were divided into high and low aspiration pressure groups and were then divided into 6 subtypes according to the different cut rates (0, 300, 600, 800, 1500, or 2500 cuts per minute [cpm]). Other samples were treated with dexamethasone sodium phosphate for 48 hours with or without further culturing in cell culture media afterward. The cell viability in each subtype group was determined using trypan blue staining and the Cell Counting Kit-8. RESULTS: The number of viable cells was reduced with increasing cut speed under high aspiration pressure. Cell viability began to decrease at 600 cpm and was lowest at 2500 cpm. Exposure to dexamethasone sodium phosphate induced destruction of cellular structure and a significant reduction in cell viability. However, cell viability could be recovered with further culture in cell culture media for 1 week. CONCLUSIONS: A cut rate of 600 cpm or less is recommended during diagnostic vitrectomy to confirm a clinical suspicion of primary intraocular lymphoma. Corticosteroid treatment can lower the diagnostic yield due to reduced cell viability and damaged cellular structure.


Assuntos
Linfoma de Burkitt/patologia , Neoplasias Oculares/patologia , Vitrectomia/métodos , Corpo Vítreo/patologia , Idoso , Biópsia , Linfoma de Burkitt/tratamento farmacológico , Sobrevivência Celular , Dexametasona/farmacologia , Neoplasias Oculares/tratamento farmacológico , Feminino , Glucocorticoides/farmacologia , Humanos , Masculino , Sucção , Células Tumorais Cultivadas
12.
Am J Physiol Gastrointest Liver Physiol ; 307(1): G16-23, 2014 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-24833705

RESUMO

Individuals with familial adenomatous polyposis (FAP) harbor a germline mutation in adenomatous polyposis coli (APC). The major clinical manifestation is development of multiple colonic tumors at a young age due to stochastic loss of the remaining APC allele. Extracolonic features, including periampullary tumors, gastric abnormalities, and congenital hypertrophy of the retinal pigment epithelium, may occur. The objective of this study was to develop a mouse model that simulates these features of FAP. We combined our Lrig1-CreERT2/+ mice with Apcfl/+ mice, eliminated one copy of Apc in leucine-rich repeats and immunoglobulin-like domains protein 1 (Lrig1)-positive (Lrig1(+)) progenitor cells with tamoxifen injection, and monitored tumor formation in the colon by colonoscopy and PET. Initial loss of one Apc allele in Lrig1(+) cells results in a predictable pattern of preneoplastic changes, culminating in multiple distal colonic tumors within 50 days of induction, as well as the extracolonic manifestations of FAP mentioned above. We show that tumor formation can be monitored by noninvasive PET imaging. This inducible stem cell-driven model recapitulates features of FAP and offers a tractable platform on which therapeutic interventions can be monitored over time by colonoscopy and noninvasive imaging.


Assuntos
Polipose Adenomatosa do Colo/metabolismo , Colo/metabolismo , Genes APC , Glicoproteínas de Membrana/metabolismo , Células-Tronco Neoplásicas/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Lesões Pré-Cancerosas/metabolismo , Polipose Adenomatosa do Colo/diagnóstico por imagem , Polipose Adenomatosa do Colo/genética , Polipose Adenomatosa do Colo/patologia , Animais , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Colo/diagnóstico por imagem , Colo/patologia , Colonoscopia , Modelos Animais de Doenças , Hipertrofia , Glicoproteínas de Membrana/genética , Camundongos , Camundongos Transgênicos , Células-Tronco Neoplásicas/patologia , Proteínas do Tecido Nervoso/genética , Tomografia por Emissão de Pósitrons , Lesões Pré-Cancerosas/diagnóstico por imagem , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/patologia , Epitélio Pigmentado da Retina/metabolismo , Epitélio Pigmentado da Retina/patologia , Fatores de Tempo
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