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1.
Allergy ; 79(3): 690-701, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38071735

RESUMO

BACKGROUND: Vaccine-associated anaphylaxis is a rare but life-threatening reaction that occurs within minutes to hours of exposure to allergens. As studies utilizing large-scale data to investigate this topic are limited, further research is needed to assess its burden, long-term trends, and associated risk factors so as to gain a comprehensive understanding of vaccine-associated anaphylaxis globally. Therefore, this study aimed to investigate the global burden of vaccine-associated anaphylaxis and related vaccines. METHOD: This study utilized the World Health Organization International Pharmacovigilance Database, in which reports of vaccine-associated anaphylaxis between 1967 and 2023 were obtained (total reports = 131,255,418). We estimated the global reporting counts, reported odds ratio (ROR), and information component (IC) to identify the relationship between 19 vaccines and associated anaphylaxis in 156 countries and territories. RESULTS: We identified 31,676 reports of vaccine-associated anaphylaxis among 363,290 reports of all-cause anaphylaxis. The cumulative number of reports on vaccine-associated anaphylaxis has gradually increased over time, with a dramatic increase after 2020, owing to reports of COVID-19 mRNA vaccine-associated anaphylaxis. The typhoid vaccines were associated with the most anaphylactic reports (ROR: 4.35; IC0.25 : 1.86), followed by encephalitis (3.27; 1.45), hepatitis B (2.69; 1.30), cholera (2.65; 0.54), hepatitis A (2.44; 1.12), influenza (2.36; 1.16), inactivated whole-virus COVID-19 (2.21; 1.02), and COVID-19 mRNA vaccines (1.89; 0.79). In terms of age- and sex-specific risks, vaccine-associated anaphylaxis reports develop more frequently in females and at young ages. The Ad5-vectored COVID-19 vaccine anaphylaxis reports were associated with the highest fatality rate (15.0%). CONCLUSIONS: Although multiple vaccines are associated with various spectra and risks of anaphylaxis, clinicians should recognize the possibility of anaphylaxis occurring with all vaccines, particularly the COVID-19 mRNA and inactivated whole-virus COVID-19 vaccines, and consider the risk factors associated with vaccine anaphylaxis reports. Further studies are warranted to identify better ways of preventing vaccine-associated anaphylaxis.


Assuntos
Anafilaxia , Vacinas contra COVID-19 , Vacinas , Feminino , Humanos , Masculino , Sistemas de Notificação de Reações Adversas a Medicamentos , Anafilaxia/etiologia , Anafilaxia/induzido quimicamente , Vacinas contra COVID-19/efeitos adversos , Vacinas contra Influenza/efeitos adversos , Farmacovigilância , Vacinas/efeitos adversos
2.
J Am Chem Soc ; 145(50): 27587-27600, 2023 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-37996388

RESUMO

Photodynamic therapy (PDT) has been used to reduce cancerous and precancerous cells via reactive oxygen species (ROS) generation from photosensitizers. Numerous photosensitizers are available today to treat a variety of diseases, but their therapeutic efficacy is hindered within the tumor microenvironment, and there are safety concerns associated with their non-specific activation. In this work, we disclosed a nano-therapeutic based on in situ activatable nitrobenzene-cysteine-copper(II) nano-complexes (NCCNs) that work within cancer cells. Among the NCCNs, CyP shows outstanding potential as a promising candidate for programmed photodynamic cancer therapy with its unique properties such as (i) bright near-infrared imaging, (ii) chemodynamic therapeutic effect, (iii) photodynamic therapeutic effect (types I and II), and (iv) anti-cancer effect by anti-angiogenesis in early cancer stage under light. Overall, this work opens up exciting possibilities for the development of innovative and effective treatments for cancer, paving the way for future advancements in the clinical medicine field.


Assuntos
Neoplasias , Fotoquimioterapia , Humanos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Cobre/uso terapêutico , Cisteína/uso terapêutico , Fotoquimioterapia/métodos , Neoplasias/tratamento farmacológico , Nitrobenzenos , Espécies Reativas de Oxigênio , Linhagem Celular Tumoral , Microambiente Tumoral
3.
Int J Mol Sci ; 24(14)2023 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-37511005

RESUMO

Facial nerve palsy directly impacts the quality of life, with patients with facial nerve palsy showing increased rates of depression and limitations in social activities. Although facial nerve palsy is not life-threatening, it can devastate the emotional and social lives of affected individuals. Hence, improving the prognosis of patients with this condition is of vital importance. The prognosis of patients with facial nerve palsy is determined by the cause of the disease, the degree of damage, and the treatment provided. The facial nerve can be easily damaged by middle ear and temporal bone surgery, trauma or infection, and tumors of the peripheral facial nerve or tumors surrounding the nerve secondary to systemic disease. In addition, idiopathic, acquired immunodeficiency syndrome and autoimmune diseases may damage the facial nerve. The treatment used for facial paralysis depends on the cause. Treatment of facial nerve amputation injury varies depending on the degree of facial nerve damage, comorbidities, and duration of injury. Recently, interest has increased in Toll-like receptors (TLRs) related to innate immune responses, as these receptors are known to be related to nerve regeneration. In addition to innate immune cells, both neurons and glia of the central nervous system (CNS) and peripheral nervous system (PNS) express TLRs. A comprehensive literature review was conducted to assess the expression and role of TLRs in peripheral nerve injury and subsequent regeneration. Studies conducted on rats and mice have demonstrated the expression of TLR1-13. Among these, TLR2-5 and TLR7 have received the most research attention in relation to facial nerve degeneration and regeneration. TLR10, TLR11, and TLR13 increase during compression injury of the facial nerve, whereas during cutting injury, TLR1-5, TLR8, and TLR10-13 increase, indicating that these TLRs are involved in the degeneration and regeneration of the facial nerve following each type of injury. Inadequate TLR expression or absence of TLR responses can hinder regeneration after facial nerve damage. Animal studies suggest that TLRs play an important role in facial nerve degeneration and regeneration.


Assuntos
Traumatismos do Nervo Facial , Camundongos , Ratos , Animais , Receptor 1 Toll-Like , Nervo Facial , Qualidade de Vida , Receptores Toll-Like , Degeneração Neural , Regeneração Nervosa , Paralisia
4.
Int J Mol Sci ; 22(9)2021 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-34066483

RESUMO

Despite advances in microsurgical technology and an improved understanding of nerve regeneration, obtaining satisfactory results after facial nerve injury remains a difficult clinical problem. Among existing peripheral nerve regeneration studies, relatively few have focused on the facial nerve, particularly how experimental studies of the facial nerve using animal models play an essential role in understanding functional outcomes and how such studies can lead to improved axon regeneration after nerve injury. The purpose of this article is to review current perspectives on strategies for applying potential therapeutic methods for facial nerve regeneration. To this end, we searched Embase, PubMed, and the Cochrane library using keywords, and after applying exclusion criteria, obtained a total of 31 qualifying experimental studies. We then summarize the fundamental experimental studies on facial nerve regeneration, highlighting recent bioengineering studies employing various strategies for supporting facial nerve regeneration, including nerve conduits with stem cells, neurotrophic factors, and/or other therapeutics. Our summary of the methods and results of these previous reports reveal a common feature among studies, showing that various neurotrophic factors arising from injured nerves contribute to a microenvironment that plays an important role in functional recovery. In most cases, histological examinations showed that this microenvironmental influence increased axonal diameter as well as myelination thickness. Such an analysis of available research on facial nerve injury and regeneration represents the first step toward future therapeutic strategies.


Assuntos
Traumatismos do Nervo Facial/terapia , Nervo Facial/fisiopatologia , Regeneração Nervosa/fisiologia , Animais , Modelos Animais de Doenças , Traumatismos do Nervo Facial/fisiopatologia , Engenharia Tecidual
5.
Neurochem Res ; 44(8): 1964-1976, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31218567

RESUMO

Schwann cells are essential glial cells in the peripheral nervous system (PNS), and dysfunction of Schwann cells can induce various peripheral neurodegenerative diseases. Oxidative stress has been implicated as a causative factor in degenerative nerve diseases; however, there no effective molecules are available to inhibit nerve degeneration in peripheral neurodegenerative diseases. Ethyl pyruvate (EP) is a candidate regulator of oxidative stress, targeting Schwann cells during peripheral nerve degeneration. Here, we investigated the effects of EP on axonal degradation, demyelination, transcriptional regulation, and macrophage recruitment during Wallerian degeneration of the sciatic nerve, ex vivo and in vivo. EP prevented the expression of neuronal nitric oxide synthase (NOS1), but not that of inducible nitric oxide synthase (NOS2), during Wallerian degeneration. These results suggest that effect of EP on Schwann cells may protect against peripheral nerve degeneration through its NOS1-specific regulation.


Assuntos
Inibidores Enzimáticos/uso terapêutico , Fármacos Neuroprotetores/uso terapêutico , Óxido Nítrico Sintase Tipo I/antagonistas & inibidores , Piruvatos/uso terapêutico , Células de Schwann/efeitos dos fármacos , Degeneração Walleriana/prevenção & controle , Animais , Axônios/efeitos dos fármacos , Doenças Desmielinizantes/patologia , Doenças Desmielinizantes/prevenção & controle , Macrófagos/efeitos dos fármacos , Masculino , Camundongos Endogâmicos C57BL , Bainha de Mielina/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-jun/metabolismo , Nervo Isquiático/efeitos dos fármacos , Nervo Isquiático/patologia , Degeneração Walleriana/patologia
6.
Eur Arch Otorhinolaryngol ; 276(4): 1011-1016, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30707280

RESUMO

PURPOSE: Patients with Ramsay-Hunt syndrome have a poorer prognosis than patients with Bell's palsy. Factors of metabolic syndrome affecting prognosis were therefore compared between patients with Ramsay-Hunt syndrome and those with Bell's palsy. METHODS: This retrospective study included 106 with Ramsay-Hunt syndrome and 182 with Bell's palsy. Age, sex, body mass index, blood pressure, blood test results, and ENoG results, stratified by House-Brackmann grade, were compared in patients with Ramsay-Hunt syndrome and Bell's palsy. Both groups of patients were treated with steroids and the antiviral agent famciclovir. RESULTS: Age, sex, body mass index, dyslipidemia, triglyceride, diabetes, hypertension, and onset of palsy did not differ in patients with Ramsay-Hunt syndrome and Bell's palsy. Rates of favorable recovery in patients with severe facial palsy and DM were lower in patients with Ramsay-Hunt syndrome than with Bell's palsy and were also lower in low-weight, normal weight, and overweight patients with Ramsay-Hunt syndrome than with Bell's palsy. Rates of favorable recovery in patients with severe facial palsy and normal HDL, as well as in patients with severe facial palsy and < 10% ENoG, were lower in patients with Ramsay-Hunt syndrome than with Bell's palsy. CONCLUSIONS: Among patients with severe facial palsy, along with diabetes and < 10% ENoG, unfavorable recovery rates were significantly higher in those with Ramsay-Hunt syndrome than with Bell's palsy.


Assuntos
Paralisia de Bell , Herpes Zoster da Orelha Externa , Adulto , Fatores Etários , Paralisia de Bell/complicações , Paralisia de Bell/tratamento farmacológico , Pressão Sanguínea , Índice de Massa Corporal , Complicações do Diabetes , Feminino , Herpes Zoster da Orelha Externa/complicações , Herpes Zoster da Orelha Externa/tratamento farmacológico , Humanos , Hipertensão/complicações , Masculino , Síndrome Metabólica/complicações , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Esteroides/uso terapêutico , Infecção pelo Vírus da Varicela-Zoster/complicações
7.
ORL J Otorhinolaryngol Relat Spec ; 81(2-3): 130-137, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31117094

RESUMO

BACKGROUND: Prediction of the severity and outcomes of Ramsay Hunt syndrome (RHS) is difficult. OBJECTIVES: The aim of this study was to evaluate the predictive power of the neutrophil-to-lymphocyte ratio (NLR) for the severity and outcomes of RHS. MATERIAL AND METHODS: From 2007 to 2017, a retrospective study of 102 hospitalized patients with RHS was conducted. The degree of paralysis was assessed by determining the House-Brackmann (H-B) grade. Obesity, hypertension, and diabetes mellitus were assessed, and the blood NLR and platelet-to-lymphocyte ratio were determined. The patients received steroids and antivirals, and were followed in the outpatient department at 1, 4, 12, and 24 weeks. RESULTS: The H-B grade of the high-NLR group was significantly higher than that of the normal-NLR group (p = 0.039), and the probability of complete recovery was significantly lower in the high-NLR group (p = 0.048). CONCLUSIONS: Patients with RHS who have an elevated NLR have poor outcomes in terms of the H-B grade. Therefore, the NLR may be useful for evaluating the prognosis of patients with RHS.


Assuntos
Antivirais/uso terapêutico , Glucocorticoides/uso terapêutico , Herpes Zoster da Orelha Externa/sangue , Linfócitos/patologia , Neutrófilos/patologia , Recuperação de Função Fisiológica , Eletromiografia , Paralisia Facial/diagnóstico , Paralisia Facial/etiologia , Feminino , Seguimentos , Herpes Zoster da Orelha Externa/complicações , Herpes Zoster da Orelha Externa/tratamento farmacológico , Humanos , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Índice de Gravidade de Doença
8.
Sensors (Basel) ; 19(11)2019 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-31159266

RESUMO

We report a new Schiff base fluorescent probe which senses ferric ion, Fe(III), with a significant fluorescence enhancement response. The probe showed high sensitivity (0.8 ppb), and fast response time (<10 s) of Fe(III) in aqueous media. In addition, the probe showed the ability to sense Fe(III) in a HeLa cancer cell line, with very low cytotoxicity. As a new bio-imaging probe for Fe(III), it gave bright fluorescent images in confocal laser scanning microscopy (CLSM).


Assuntos
Técnicas Biossensoriais/métodos , Ferro/análise , Bases de Schiff/química , Fluorescência , Corantes Fluorescentes/química , Células HeLa , Humanos , Ferro/química , Microscopia Confocal
9.
Clin Otolaryngol ; 44(3): 305-312, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30672667

RESUMO

OBJECTIVE: Although recurrent facial palsy was first reported in 1871, the aetiology, definitions, classifications, pathogenesis, treatment options and prognosis have not been clearly determined. There have been no systematic reviews and meta-analyses of recurrent Bell's palsy. The purpose of this study was to evaluate the clinical manifestations of recurrent Bell's palsy through a systematic review and meta-analysis. DESIGN: The SCOPUS, PubMed, Cochrane Library and EBSCO databases were searched through 1 May 2018, using the search terms "recurrent Bell's palsy" and "recurrent facial palsy," for studies involving patients with recurrent Bell's palsy. Reference lists of eligible studies were also reviewed. RESULTS: A search of titles and abstracts in these four databases identified 222 studies; of these, 27 studies, involving 1041 patients from 13 countries, were analysed. The mean percentage of patients who experienced recurrence of Bell's palsy ranged from 0.8% to 19.4%. Five studies that included 191 patients were included in the meta-analysis. CONCLUSIONS: Among patients previously affected by Bell's palsy, the mean incidence of recurrent Bell's palsy was 6.5%. Sidedness of recurrent disease, relative to the side of the original disease, had no effect on patient prognosis. Of all patients with Bell's palsy, 66.0% recovered completely, with the recovery rate lower in patients with recurrent than with primary Bell's palsy.


Assuntos
Paralisia de Bell/epidemiologia , Qualidade de Vida , Saúde Global , Humanos , Incidência , Recidiva
10.
Neural Plast ; 2018: 1824713, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29853837

RESUMO

Synaptic plasticity is important for maintaining normal neuronal activity and proper neuronal functioning in the nervous system. It is crucial for regulating synaptic transmission or electrical signal transduction to neuronal networks, for sharing essential information among neurons, and for maintaining homeostasis in the body. Moreover, changes in synaptic or neural plasticity are associated with many neuropsychiatric conditions, such as schizophrenia (SCZ), bipolar disorder (BP), major depressive disorder (MDD), and Alzheimer's disease (AD). The improper maintenance of neural plasticity causes incorrect neurotransmitter transmission, which can also cause neuropsychiatric conditions. Gas neurotransmitters (gasotransmitters), such as hydrogen sulfide (H2S), nitric oxide (NO), and carbon monoxide (CO), play roles in maintaining synaptic plasticity and in helping to restore such plasticity in the neuronal architecture in the central nervous system (CNS). Indeed, the upregulation or downregulation of these gasotransmitters may cause neuropsychiatric conditions, and their amelioration may restore synaptic plasticity and proper neuronal functioning and thereby improve such conditions. Understanding the specific molecular mechanisms underpinning these effects can help identify ways to treat these neuropsychiatric conditions.


Assuntos
Gasotransmissores/fisiologia , Transtornos Mentais/metabolismo , Transtornos Mentais/psicologia , Plasticidade Neuronal/fisiologia , Animais , Monóxido de Carbono/metabolismo , Homeostase/fisiologia , Humanos , Sulfeto de Hidrogênio/metabolismo , Transtornos Mentais/diagnóstico , Neurotransmissores/metabolismo , Óxido Nítrico/metabolismo
11.
Angew Chem Int Ed Engl ; 57(32): 10142-10147, 2018 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-29873167

RESUMO

Vesicles exchange their contents through membrane fusion processes, kiss-and-run and full-collapse fusion. Indirect observation of these fusion processes using artificial vesicles enhanced our understanding on the molecular mechanisms involved. Direct observation of the fusion processes in a real biological system, however, remains a challenge owing to many technical obstacles. We report a ratiometric two-photon probe offering real-time tracking of lysosomal ATP with quantitative information for the first time. By applying the probe to two-photon live-cell imaging, the lysosomal membrane fusion process in cells has been directly observed and the concentration of its content, lysosomal ATP, has been measured. Results show that the kiss-and-run process between lysosomes proceeds through repeated transient interactions with gradual content mixing, whereas the full-fusion process occurs at once. Furthermore, it is confirmed that both the fusion processes proceed with conservation of the content. Such a small-molecule probe exerts minimal disturbance and hence has potential for studying various biological processes associated with lysosomal ATP.


Assuntos
Trifosfato de Adenosina/análise , Corantes Fluorescentes/química , Membranas Intracelulares/química , Lisossomos/química , Fótons , Trifosfato de Adenosina/metabolismo , Células HeLa , Humanos , Membranas Intracelulares/metabolismo , Lisossomos/metabolismo , Estrutura Molecular , Imagem Óptica
12.
J Fluoresc ; 27(6): 2231-2238, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28823107

RESUMO

8-Amino-BODIPY (boron-dipyrromethane) dyes show bright blue fluorescence. Disclosed here are synthesis and characterization of the photophysical properties of a series of functionalized 8-Amino-BODIPY (BP1-4) for protein labeling. The compact structure and solvent-insensitive absorption property of the dye are desirable features for protein labeling. For the model protein, bovine serum albumin (BSA), the labeling proceeds under mild condition via amide bond formation or thiol-ene conjugation with maintaining the bright blue fluorescence. The chromatography and mass spectroscopy analysis clearly support the labeling of the BODIPY dye on the BSA. The protein labeling with blue-emitting BODIPY would be applicable for studying protein dynamics and fluorescence resonance energy transfer (FRET) with intrinsic biomolecules.


Assuntos
Compostos de Boro/química , Fluorescência , Corantes Fluorescentes/química , Soroalbumina Bovina/química , Animais , Bovinos , Transferência Ressonante de Energia de Fluorescência , Modelos Moleculares
13.
Eur Arch Otorhinolaryngol ; 273(7): 1755-60, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26319412

RESUMO

Incomplete recovery of facial motor function continues to be long-term sequelae in some patients with Bell's palsy. The purpose of this study was to investigate the efficacy of transmastoid facial nerve decompression after steroid and antiviral treatment in patients with late stage Bell's palsy. Twelve patients underwent surgical decompression for Bell's palsy 21-70 days after onset, whereas 22 patients were followed up after steroid and antiviral therapy without decompression. Surgical criteria included greater than 90 % degeneration on electroneuronography and no voluntary electromyography potentials. This study was a retrospective study of electrodiagnostic data and medical chart review between 2006 and 2013. Recovery from facial palsy was assessed using the House-Brackmann grading system. Final recovery rate did not differ significantly in the two groups; however, all patients in the decompression group recovered to at least House-Brackmann grade III at final follow-up. Although postoperative hearing threshold was increased in both groups, there was no significant between group difference in hearing threshold. Transmastoid decompression of the facial nerve in patients with severe late stage Bell's palsy at risk for a poor facial nerve outcome reduced severe complications of facial palsy with minimal morbidity.


Assuntos
Paralisia de Bell/cirurgia , Descompressão Cirúrgica , Paralisia Facial/cirurgia , Adolescente , Adulto , Idoso , Antivirais/uso terapêutico , Paralisia de Bell/diagnóstico , Paralisia de Bell/tratamento farmacológico , Eletromiografia , Paralisia Facial/diagnóstico , Paralisia Facial/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
14.
Eur Arch Otorhinolaryngol ; 273(10): 3083-90, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26873601

RESUMO

The relative effectiveness of acyclovir and famciclovir in the treatment of Bell's palsy is unclear. This study therefore compared recovery outcomes in patients with Bell's palsy treated with acyclovir and famciclovir. The study cohort consisted of patients with facial palsy who visited the outpatient clinic between January 2006 and January 2014. Patients were treated with prednisolone plus either acyclovir (n = 457) or famciclovir (n = 245). Patient outcomes were measured using the House-Brackmann scale according to initial severity of disease and underlying disease. The overall recovery rate tended to be higher in the famciclovir than in the acyclovir group. The rate of recovery in patients with initially severe facial palsy (grades V and VI) was significantly higher in the famciclovir than in the acyclovir group (p = 0.01), whereas the rates of recovery in patients with initially moderate palsy (grade III-IV) were similar in the two groups. The overall recovery rates in patients without hypertension or diabetes mellitus were higher in the famciclovir than in the acyclovir group, but the difference was not statistically significant. Treatment with steroid plus famciclovir was more effective than treatment with steroid plus acyclovir in patients with severe facial palsy. Famciclovir may be the antiviral agent of choice in the treatment of patients with severe facial palsy.


Assuntos
2-Aminopurina/análogos & derivados , Aciclovir/uso terapêutico , Antivirais/uso terapêutico , Paralisia de Bell/tratamento farmacológico , 2-Aminopurina/uso terapêutico , Diabetes Mellitus , Quimioterapia Combinada , Famciclovir , Feminino , Glucocorticoides/uso terapêutico , Humanos , Hipertensão , Masculino , Pessoa de Meia-Idade , Prednisolona/uso terapêutico
15.
J Am Chem Soc ; 137(21): 6781-9, 2015 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-25951499

RESUMO

Fluorescence imaging of tissues offer an essential means for studying biological systems. Autofluorescence becomes a serious issue in tissue imaging under excitation at UV-vis wavelengths where biological molecules compete with the fluorophore. To address this critical issue, a novel class of fluorophores that can be excited at ∼900 nm under two-photon excitation conditions and emits in the red wavelength region (≥600 nm) has been disclosed. The new π-extended dipolar dye system shows several advantageous features including minimal autofluorescence in tissue imaging and pronounced solvent-sensitive emission behavior, compared with a widely used two-photon absorbing dye, acedan. As an important application of the new dye system, one of the dyes was developed into a fluorescent probe for amyloid-ß plaques, a key biomarker of Alzheimer's disease. The probe enabled in vivo imaging of amyloid-ß plaques in a disease-model mouse, with negligible background signal. The new dye system has great potential for the development of other types of two-photon fluorescent probes and tags for imaging of tissues with minimal autofluorescence.


Assuntos
Doença de Alzheimer/diagnóstico , Peptídeos beta-Amiloides/análise , Corantes Fluorescentes/química , Imagem Óptica , Fótons , Animais , Linhagem Celular Tumoral , Sobrevivência Celular , Modelos Animais de Doenças , Corantes Fluorescentes/síntese química , Humanos , Camundongos , Camundongos Transgênicos , Estrutura Molecular
16.
J Neurochem ; 132(2): 230-42, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25123509

RESUMO

Hydrogen sulfide (H2 S) functions as a physiological gas transmitter in both normal and pathophysiological cellular events. H2 S is produced from substances by three enzymes: cystathionine ß-synthase (CBS), cystathionine γ-lyase (CSE), and 3-mercaptopyruvate sulfurtransferase (MST). In human tissues, these enzymes are involved in tissue-specific biochemical pathways for H2 S production. For example, CBS and cysteine aminotransferase/MST are present in the brain, but CSE is not. Thus, we examined the expression of H2 S production-related enzymes in peripheral nerves. Here, we found that CSE and MST/cysteine aminotransferase, but not CBS, were present in normal peripheral nerves. In addition, injured sciatic nerves in vivo up-regulated CSE in Schwann cells during Wallerian degeneration (WD); however, CSE was not up-regulated in peripheral axons. Using an ex vivo sciatic nerve explant culture, we found that the inhibition of H2 S production broadly prevented the process of nerve degeneration, including myelin fragmentation, axonal degradation, Schwann cell dedifferentiation, and Schwann cell proliferation in vitro and in vivo. Thus, these results indicate that H2 S signaling is essential for Schwann cell responses to peripheral nerve injury. Hydrogen sulfide (H2 S) functions as a physiological gas transmitter in both normal and pathophysiological cellular events. H2 S is produced from cystathionine ß-synthase (CBS), cystathionine γ-lyase (CSE), and 3-mercaptopyruvate sulfur transferase (MST). Here, we found that CSE and MST/CAT were present in normal peripheral nerves. Injured static nerves in vivo up-regulated CSE in Schwann cells during Wallerian degeneration, but CSE was not up-regulated in peripheral axons.


Assuntos
Sulfeto de Hidrogênio/metabolismo , Traumatismos dos Nervos Periféricos/metabolismo , Células de Schwann/metabolismo , Nervo Isquiático/lesões , Degeneração Walleriana/metabolismo , Animais , Axotomia , Cistationina beta-Sintase/metabolismo , Cistationina gama-Liase/metabolismo , Cisteína/farmacologia , Etilmaleimida/farmacologia , Sulfeto de Hidrogênio/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Técnicas de Cultura de Órgãos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sulfurtransferases/metabolismo , Transaminases/metabolismo
17.
Anal Chem ; 87(2): 1188-95, 2015 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-25495776

RESUMO

Hydrogen sulfide has emerged as an exciting endogenous gasotransmitter in addition to nitric oxide and carbon dioxide. Noninvasive detection methods for hydrogen sulfide thus become indispensable tools for studying its diverse roles in biological systems. Accordingly, fluorescent probes for hydrogen sulfide have received great attention in recent years. A practically useful fluorescent probe for bioimaging of hydrogen sulfide should be selective, sensitive, fast-responsive, biocompatible, observable in the biological optical window, and capable of deep-tissue imaging. These sensing properties, however, are extremely difficult to achieve at the same time. Disclosed here is the two-photon fluorescent probe that meets all of these criteria. The probe belongs to a Michael acceptor system, which raised a serious selectivity issue over the competing biothiols such as cysteine and glutathione. We have addressed the selectivity issue by optimizing the electronic and steric interactions between biothiols and the probe, in addition to achieving very high sensitivity, fast-response, and biocompatibility. Also, the sensing mechanism suggested in the literature was revised. The probe thus enables us to image the endogenously produced hydrogen sulfide with negligible interference from other biothiols in live cells. The excellent sensing properties of the probe combined with its capability of bioimaging thus make it a practically useful tool for further studying biological roles of hydrogen sulfide.


Assuntos
Benzaldeídos/química , Cisteína/análise , Corantes Fluorescentes/química , Glutationa/análise , Sulfeto de Hidrogênio/análise , Técnicas Biossensoriais , Células HeLa , Humanos , Imagem Óptica , Compostos de Sulfidrila/análise
18.
Biochem Biophys Res Commun ; 465(4): 758-63, 2015 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-26299927

RESUMO

Exendin-4, an analog of glucagon-like peptide-1, has shown to have beneficial effects on endothelial function, and was recently approved for the treatment of diabetes. In previous studies, we showed that exendin-4 induces angiogenesis in in vitro and ex vivo assays; in this study, we assessed the proangiogenic effects of exendin-4 in vivo using a mouse hindlimb ischemia model. Treatment with exendin-4 for three days mitigated hindlimb and gastrocnemius muscle fiber necrosis. Hindlimb perfusion was determined using indocyanine green fluorescence dynamics that showed, significantly higher blood flow rate to the ischemic hindlimbs in an exendin-4-treated group. Immunohistochemistry assay showed that exendin-4 increased CD31-positive areas in the gastrocnemius muscle of ischemic limbs. Furthermore, treatment of the hindlimbs of ischemic mice with exendin-4 increased vascular endothelial growth factor (VEGF) and phospho-extracellular signal-related kinase (ERK) on western blot analysis. Our data demonstrate that exendin-4 prevents hindlimb ischemic injury by inducing vessels via VEGF angiogenic-related pathways. These findings suggest that exendin-4 has potential as a therapeutic agent for vascular diseases that stimulate angiogenesis.


Assuntos
Indutores da Angiogênese/uso terapêutico , Isquemia/tratamento farmacológico , Neovascularização Fisiológica/efeitos dos fármacos , Peptídeos/uso terapêutico , Peçonhas/uso terapêutico , Animais , Modelos Animais de Doenças , Exenatida , Hemodinâmica/efeitos dos fármacos , Membro Posterior/irrigação sanguínea , Membro Posterior/lesões , Isquemia/patologia , Isquemia/fisiopatologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Fator A de Crescimento do Endotélio Vascular/metabolismo
19.
Cell Mol Neurobiol ; 34(3): 361-8, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24363123

RESUMO

Adenosine 5'-triphosphate (ATP) is implicated in intercellular communication as a neurotransmitter in the peripheral nervous system. In addition, ATP is known as lysosomal exocytosis activator. In this study, we investigated the role of extracellular ATP on demyelination during Wallerian degeneration (WD) using ex vivo and in vivo nerve degeneration models. We found that extracellular ATP inhibited myelin fragmentation and axonal degradation during WD. Furthermore, metformin and chlorpromazine, lysosomal exocytosis antagonists blocked the effect of ATP on the inhibition of demyelination. Thus, these findings indicate that ATP-induced-lysosomal exocytosis may be involved in demyelination during WD.


Assuntos
Trifosfato de Adenosina/uso terapêutico , Doenças Desmielinizantes/prevenção & controle , Células de Schwann/efeitos dos fármacos , Degeneração Walleriana/tratamento farmacológico , Trifosfato de Adenosina/farmacologia , Animais , Células Cultivadas , Doenças Desmielinizantes/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Técnicas de Cultura de Órgãos , Células de Schwann/patologia , Degeneração Walleriana/patologia
20.
ACS Appl Mater Interfaces ; 16(4): 4493-4504, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38253428

RESUMO

Cervical cancer screening is a crucial field of femtech (female technology). In this work, we disclosed a new femtech solution─a simple, straightforward, and on-site applicable urine-based cervical cancer diagnostic method using a fluorescent biothiol probe. Our newly developed nitrobenzene-based fluorescent probe, named NPS-B, effectively differentiates between cysteine and homocysteine within urine samples via controlled Smiles rearrangement. The analysis of emission-based signals offers the potential utility of this method in cervical cancer. NPS-B was designed by considering the substitution effect and structural polarity of the nitrobenzene-based fluorophore. This controlled modification of nitrobenzene-induced substantial intramolecular charge transfer changes in the fluorophore when exposed to biothiols, resulting in significant changes in photophysical properties. NPS-B displayed different emissions of cysteine and homocysteine in clinical human urine (without prior urine treatment). Overall, our findings provide insights not only into fundamental chemical science but also into the broader domain of applied sciences.


Assuntos
Cisteína , Neoplasias do Colo do Útero , Feminino , Humanos , Cisteína/química , Corantes Fluorescentes/química , Neoplasias do Colo do Útero/diagnóstico , Detecção Precoce de Câncer , Glutationa/química , Homocisteína , Nitrobenzenos , Espectrometria de Fluorescência/métodos
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