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1.
Am J Trop Med Hyg ; 109(6): 1333-1338, 2023 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-37931292

RESUMO

Infectious conjunctivitis outbreaks remain a public health burden. This study focuses on the pathogen and antimicrobial resistance (AMR) profiles identified in Niger. Sixty-two patients with acute infectious conjunctivitis who presented to health posts were enrolled from December 2021 to May 2022. Nasal and conjunctival swabs were obtained from each patient. Unbiased RNA deep sequencing (RNA-seq) was used to identify associated pathogens. A pathogen was identified in 39 patients (63%; 95% CI, 50-74). Of those, an RNA virus was detected in 23 patients (59%; 95% CI, 43-73). RNA viruses were diverse and included human coronaviruses (HCoVs): SARS-CoV-2, HCoV-229E, HCoV-HKU1, and HCoV-OC43. A DNA virus was identified in 11 patients (28%; 95% CI, 17-44). Of those, four patients had a coinfection with an RNA virus and two patients had a coinfection with both an RNA virus and a bacterium. DNA viruses were predominantly human herpesvirus (cytomegalovirus, Epstein-Barr virus, human herpesvirus 8) and human adenovirus species B, C, and F. Eighteen patients (46%; 95% CI, 32-61) had a bacteria-associated infection that included Haemophilus influenza, Haemophilus aegyptius, Staphylococcus aureus, Streptococcus pneumoniae, and Moraxella spp. Antimicrobial resistance determinants were detected in either the conjunctiva or nasal samples of 20 patients (32%; 95% CI, 22-45) and were found to be more diverse in the nose (Shannon alpha diversity, 1.12 [95% CI, 1.05-1.26] versus 1.02 [95% CI, 1.00-1.05], P = 0.01). These results suggest the potential utility of leveraging RNA-seq to surveil pathogens and AMR for ocular infections.


Assuntos
Coinfecção , Conjuntivite , Infecções por Vírus Epstein-Barr , Infecções Respiratórias , Humanos , Antibacterianos , Infecções Respiratórias/epidemiologia , Níger/epidemiologia , Farmacorresistência Bacteriana , Herpesvirus Humano 4
2.
JAMA Ophthalmol ; 141(12): 1140-1144, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37917077

RESUMO

Importance: Acute infectious conjunctivitis is a common ocular condition with major public health consequences. Objective: To assess regional variations and microbial etiologies of acute infectious conjunctivitis to guide treatment. Design, Setting, and Participants: In this cross-sectional study, patients with presumed acute infectious conjunctivitis were enrolled in the study at 5 sites (Honolulu, Hawaii; Los Angeles, San Francisco, and San Diego, California; and Petah-Tikva, Israel) from March 2021 to March 2023. Patients with allergic or toxic conjunctivitis were excluded. Main Outcomes and Measures: Pathogens were identified by unbiased RNA deep sequencing. Results: In all, 52 patients (mean [range] age, 48 [7-80] years; 31 females [60%]) were enrolled at 5 sites (6 patients from Honolulu, 9 from San Diego, 11 from Los Angeles, 13 from San Francisco, and 13 from Petah-Tikva). RNA deep sequencing detected human adenovirus species D in one-quarter of patients (13 of 52). A wide range of pathogens, including human coronavirus 229E, SARS-CoV-2, and herpes simplex virus type 1, was also identified, as well as several bacteria and fungi. Moreover, 62% (32 of 52) of patients presented with purulent discharge, while only 8% (4 of 52) of patients had confirmed bacterial pathogens. Conclusion and Relevance: In this cross-sectional study, pathogens associated with acute infectious conjunctivitis varied between all 5 sites in the US and Israel. Purulent discharge was a common presenting sign in this study, with a low specificity for bacteria-associated conjunctivitis, suggesting that further diagnostic workup may be necessary to inform antibiotic stewardship. Additional research on cost-effectiveness of using RNA deep sequencing is needed to ascertain whether it is better to monitor patients clinically until resolution of disease.


Assuntos
Conjuntivite , Feminino , Humanos , Pessoa de Meia-Idade , Bactérias , Conjuntivite/microbiologia , Estudos Transversais , Doença Aguda , Vigilância em Saúde Pública
3.
Cornea Open ; 2(2)2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37719281

RESUMO

Purpose: To identify pathogens associated with the 2022 conjunctivitis outbreak in Tamil Nadu, India. Methods: This prospective study was conducted in November of 2022. Patients with presumed acute infectious conjunctivitis presenting to the Aravind Eye Clinic in Madurai, India were eligible. Anterior nares and conjunctival samples from participants were obtained and processed for metagenomic RNA deep sequencing (RNA-seq). Results: Samples from 29 patients were sequenced. A pathogen was identified in 28/29 (97%) patients. Coxsackievirus A24v, a highly infectious RNA virus, was the predominant pathogen and detected in 23/29 patients. Human adenovirus D (HAdV-D), a DNA virus commonly associated with conjunctivitis outbreaks, was detected in the remaining patients (5/29). Hemorrhagic conjunctiva was documented in both HAdV-D and coxsackievirus A24v affected patients but was not the predominant clinical presentation. Phylogenetic analysis of coxsackievirus A24v revealed a recent divergence from the 2015 outbreak. Conclusions: Coxsackievirus A24v and HAdV-D were co-circulating during the 2022 conjunctivitis outbreak in Tamil Nadu, India. Clinical findings were similar between patients with HAD-V and coxsackievirus A24v associated conjunctivitis. As high-throughput technologies become more readily accessible and cost-effective, unbiased pathogen surveillance may prove useful for outbreak surveillance and control.

4.
Int Health ; 2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37650684

RESUMO

BACKGROUND: Infectious conjunctivitis is common in Nepal. MATERIALS AND METHODS: This prospective study recruited 60 patients with presumed acute infectious conjunctivitis from the B.P. Koirala Lions Center for Ophthalmic Studies in Kathmandu, Nepal. Swabs from the conjunctiva and anterior nares were processed for metagenomic RNA deep sequencing (RNA-seq). RESULTS: Pathogens were identified in 55% of cases. RNA viruses were the most common pathogen class identified. Severe acute respiratory syndrome coronavirus 2 was the most common RNA virus identified. CONCLUSIONS: Acute infectious conjunctivitis varies by location. Contrary to expectations, RNA viruses predominated. Repeat surveillance may be useful and RNA-seq allows for detection of the unexpected pathogen including RNA viruses.

5.
Optom Vis Sci ; 100(4): 276-280, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36880993

RESUMO

SIGNIFICANCE: Acute infectious conjunctivitis poses significant challenges to eye care providers. It can be highly transmissible, and because etiology is often presumed, correct treatment and management can be difficult. This study uses unbiased deep sequencing to identify causative pathogens of infectious conjunctivitis, potentially allowing for improved approaches to diagnosis and management. PURPOSES: This study aimed to identify associated pathogens of acute infectious conjunctivitis in a single ambulatory eye care center. CASE REPORTS: This study included patients who presented to the University of California Berkeley eye center with signs and symptoms suggestive of infectious conjunctivitis. From December 2021 to July 2021, samples were collected from seven subjects (ages ranging from 18 to 38). Deep sequencing identified associated pathogens in five of seven samples, including human adenovirus D, Haemophilus influenzae , Chlamydia trachomatis , and human coronavirus 229E. CONCLUSIONS: Unbiased deep sequencing identified some unexpected pathogens in subjects with acute infectious conjunctivitis. Human adenovirus D was recovered from only one patient in this series. Although all samples were obtained during the COVID-19 pandemic, only one case of human coronavirus 229E and no SARS-CoV-2 were identified.


Assuntos
COVID-19 , Conjuntivite , Humanos , Doença Aguda , California/epidemiologia , COVID-19/diagnóstico , COVID-19/epidemiologia , Sequenciamento de Nucleotídeos em Larga Escala , Pandemias
6.
Am J Trop Med Hyg ; 108(3): 595-598, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36646076

RESUMO

The first manifestation of a viral infection may be conjunctivitis. There are limited data on the etiology of viral conjunctivitis in Vanuatu, a country in the South Pacific Ocean. Patients presenting to one of two Vanuatu health centers with presumed infectious conjunctivitis were eligible if symptom onset was within 14 days of screening. Conjunctival and anterior nasal swabs were obtained and subjected to unbiased RNA deep sequencing (RNA-seq) to identify DNA and RNA viruses. For samples collected from May to November 2021, RNA-seq identified a viral etiology in 12/48 patients. Human adenovirus species were the most common viruses (58%) detected, followed by human herpes viruses (cytomegalovirus, varicella zoster virus, and human herpes 7 virus). Rhinovirus C, Epstein-Barr virus, and bocavirus were also detected. In summary, the etiology for viral conjunctivitis in Vanuatu appears broad. Unbiased testing may be useful for disease surveillance.


Assuntos
Conjuntivite Viral , Conjuntivite , Infecções por Vírus Epstein-Barr , Humanos , Vanuatu , Herpesvirus Humano 4 , Herpesvirus Humano 3/genética
7.
Work ; 73(3): 977-990, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36245350

RESUMO

BACKGROUND: Musculoskeletal risks (MSRs) are a major concern among construction warehouse workers due to the lifting, carrying and lowering of heavy loads. OBJECTIVE: The objective of this study was to reduce MSRs among warehouse workers in the construction industry using virtual modelling and analysis of activities. METHODS: A preliminary study was carried out using the Standard Nordic Questionnaire. Biomechanical analysis, Ovako Working posture Assessment System (OWAS) and Rapid Upper Limb Assessment (RULA) were used to analyse the material handling activities. Virtual modelling was used develop the manikins with autoclaved aerated concrete (AAC) blocks at different carriage modes and stacking heights for the analysis. RESULTS: The preliminary study results revealed a higher prevalence of risk at their lower back (73.24%) among the construction warehouse workers. Biomechanical analysis showed a higher risk at L4-L5 joint of lumbar spine during overhead and bending postures for stacking the blocks. Posture analysis results of OWAS indicated a lower risk in overhead carriage mode. Detailed analysis with RULA confirms this result. Mean compressive force values at stacking heights were showed a significant difference (p < 0.05) in 8, 13, 18 and 21 kg AAC blocks. However, stacking height with a range of 120-140 cm was found as safer to the workers by considering all block sizes. CONCLUSION: An ergonomic intervention based on safer stacking heights was developed to reduce MSRs to an acceptable range. It improves productivity of handling the AAC blocks by reducing the cycle time. The intervention can be adapted for handling of similar materials in the construction industry.


Assuntos
Indústria da Construção , Doenças Musculoesqueléticas , Sistema Musculoesquelético , Doenças Profissionais , Humanos , Ergonomia/métodos , Postura , Extremidade Superior , Doenças Musculoesqueléticas/etiologia , Doenças Musculoesqueléticas/prevenção & controle , Doenças Musculoesqueléticas/epidemiologia , Doenças Profissionais/epidemiologia
8.
Sci Rep ; 12(1): 9159, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35650306

RESUMO

Osteoarthritis (OA) is the most prevalent degenerative joint disease, resulting in joint pain, impaired movement, and structural changes. As the ability of joint tissue to resist stress is mainly imparted by fibrillar collagens in the extracellular matrix, changes in the composition and structure of collagen fibers contribute to the pathological remodeling observed in OA joints that includes cartilage degeneration, subchondral bone (SCB) sclerosis, and meniscal damage. Using the established OA model of destabilization of the medial meniscus (DMM) in C57BL/6J mice, we performed a comprehensive analysis of the content and structure of collagen fibers in the articular cartilage, subchondral bone, and menisci using complementary techniques, which included second harmonic generation microscopy and immunofluorescence staining. We found that regions exposed to increased mechanical stress in OA mice, typically closest to the site of injury, had increased collagen fiber thickness, dysregulated fiber formation, and tissue specific changes in collagen I and II (Col I and Col II) expression. In cartilage, OA was associated with decreased Col II expression in all regions, and increased Col I expression in the anterior and posterior regions. Col I fiber thickness was increased in all regions with disorganization in the center region. In the superficial SCB, all regions exhibited increased Col I expression and fiber thickness in OA mice; no changes were detected in the deeper regions of the subchondral bone except for increased Col I fiber thickness. In the menisci, OA led to increased Col I and Col II expression in the vascular and avascular regions of the anterior meniscus with increased Col I fiber thickness in these regions. Similar changes were observed only in the vascular region of the posterior meniscus. Our findings provide, for the first time, comprehensive insights into the microarchitectural changes of extracellular matrix in OA and serve as guidelines for studies investigating therapies that target collagenous changes as means to impede the progression of osteoarthritis.


Assuntos
Cartilagem Articular , Osteoartrite , Animais , Cartilagem Articular/patologia , Colágeno , Matriz Extracelular/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Osteoartrite/patologia
9.
Anal Bioanal Chem ; 414(17): 4935-4951, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35579676

RESUMO

A novel carbon dot (CD) was synthesized through the facile and simple hydrothermal method from Curcuma amada, as the precursor for the first time. These CDs with an average diameter of 4.6 nm display blue fluorescence, with excitation/emission maxima at 360/445 nm and a quantum yield of 14.1%. It exhibited high stability under different conditions and was characterized using various techniques. These CDs can be employed as a dual-sensing platform to detect tetracyclines and fluoroquinolones, two antibiotic classes. Even though antibiotics are regarded as an inevitable commodity, overuse and improper management of discarded antibiotics pose a severe threat to the environment. Herein, we developed a dual-sensing, biocompatible sensor with high selectivity and sensitivity to detect antibiotics. CD was employed as a fluorescence probe and detected tetracycline and fluoroquinolone antibiotic through inner filter effect-based fluorescence quenching and hydrogen bonding-based enhancement process, respectively. The linear range was 0-16 µM and the detection limit was 33 nM for tetracycline and 2 nM for fluoroquinolone antibiotic. As an electrochemical probe, CD selectively detected tetracycline with a lower detection limit of 0.5 nM over a linear range of 0-16 µM. Using both methods, a real sample analysis of the developed sensor exhibited accurate reliability and precision.


Assuntos
Pontos Quânticos , Tetraciclinas , Antibacterianos , Biomassa , Carbono/química , Corantes Fluorescentes/química , Fluoroquinolonas , Pontos Quânticos/química , Reprodutibilidade dos Testes , Espectrometria de Fluorescência/métodos , Tetraciclina , Tetraciclinas/análise
10.
Environ Sci Pollut Res Int ; 29(35): 53225-53237, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35278183

RESUMO

The photocatalytic activity of semiconducting silver carbonate was restricted by the lower stability and fast recombination rate of photogenerated electron-hole pairs. Sulfur-doped graphene oxide (SGO) is used as a cocatalyst for improving the photocatalytic activity of Ag2CO3 by reducing the recombination rate. A simple precipitation method was used for the modification of silver carbonate. The chemical, physical, optical, and electrochemical properties of the modified photocatalyst was characterized by XRD, SEM, TEM, UV-vis DRS, XPS, CV, impedance, and amperometry. The fabricated SGO-Ag2CO3 composite was successfully degraded various organic pollutants such as methylene blue (MB), rhodamine B(RhB), methyl orange (MO), tartrazine, and thiram with augmented mineralization. The optimization of weight percentage of the developed binary composite with 0.5% SGO-Ag2CO3 showed enhanced photocatalytic degradation and followed pseudo-first-order kinetics with rate constant 0.126. More than 90% of degradation efficiency of the pollutants within a short time promises the binary heterostructure for future industrial applications. The excellent stability and reproducibility of the composite opened a new route in the treatment of wastewater.


Assuntos
Poluentes Ambientais , Grafite , Catálise , Grafite/química , Luz , Reprodutibilidade dos Testes
11.
J Fluoresc ; 32(2): 449-471, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35064386

RESUMO

Carbon quantum dots (CQDs) have emerged as one of the most promising nanomaterials in the carbon nanostructures family in recent years due to their low toxicity, simple synthetic methods, unique fluorescence emission, good photostability, excellent water solubility, high specific surface areas and outstanding electronic properties. They have thus been employed in a wide range of applications, including fluorescent sensing, electrochemical sensing, bioimaging, drug delivery, antimicrobial studies, antioxidants, and photocatalysis. CQDs drawn great interest in sensing applications due to their unique photochemical, electrochemical and electrochemiluminescence properties. They exhibit excitation wavelength-dependent or -independent photoluminescence (PL) behaviour, high quantum yield, and promising binding ability with analytes, which make them an ideal candidate for use in PL based sensing platforms. Excessive use of agrochemicals in farm fields can pollute the environment and have potentially adverse health effects on aquatic and human life. Since there are very few monitoring techniques are available for sensing such harmful substances, there is an urgent need to develop a sensor for the facile, rapid and on-site detection and quantification of agrochemical residues in the environment. Several CQD-based fluorophores for detecting agrochemical residues employing static or dynamic quenching processes have recently been published. The key quenching mechanisms involved in the sensing process include FRET, PET and IFE. The first part of this review intends to provide a comprehensive overview of various techniques to characterize CQDs such as UV-vis., FT-IR, PL, XRD, NMR, TEM, TGA, XPS and Raman analysis. In addition application of CQDs as fluorescent sensors for agrochemical residue in different media are summarized in this reiew. The LOD values and rapid action of the sensor demonstrates significant advantages of these methods over conventional analytical procedures.


Assuntos
Agroquímicos/análise , Carbono/química , Pontos Quânticos/química , Corantes Fluorescentes , Medições Luminescentes , Espectroscopia de Ressonância Magnética , Microscopia Eletrônica de Transmissão , Espectroscopia Fotoeletrônica , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Termogravimetria , Difração de Raios X
12.
Matrix Biol ; 105: 127-143, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34995785

RESUMO

Collagen cross-linking is an important step in optimal scar formation. Myocardial infarction (MI) results in loss of cardiomyocytes that are replaced with a scar (infarct) tissue. Disintegrin and metalloproteinases (ADAMs) are membrane-bound proteases that can interact with molecules intra- and extra-cellularly to mediate various cellular functions. ADAM15 is expressed in the myocardium, however its function in heart disease has been poorly explored. We utilized mice lacking ADAM15 (Adam15-/-) and wildtype (WT) mice. MI, induced by ligation of the left anterior descending artery, resulted in a transient but significant rise in ADAM15 protein in the WT myocardium at 3-days. Following MI, Adam15-/- mice exhibited markedly higher rate of left ventricular (LV) rupture compared to WT mice (66% vs. 15%, p<0.05). Echocardiography and strain analyses showed worsened LV dysfunction in Adam15-/- mice at 3days, prior to the onset of LV rupture. Second harmonic generation imaging revealed significant disarray and reduction in fibrillar collagen density in Adam15-/- compared to WT hearts. This was associated with lower insoluble and higher soluble collagen fractions, reduced cross-linking enzyme, lysyl oxidase-1 (LOX-1), and fibronectin which is required for LOX-1 function, in Adam15-/--MI hearts. Post-MI myocardial inflammation was comparable between the genotypes. In vitro, primary adult cardiac fibroblasts from Adam15-/- mice showed suppressed activation in response to ischemia (hypoxia+nutrient depletion) compared to WT fibroblasts. Adam15-deficiency was associated with reduced PAK1(p21-activated kinase-1) levels, a regulator of fibronectin and LOX-1 expression. In female mice, the rate of post-MI LV rupture, PAK1 signaling, LOX-1 and fibronectin protein levels were comparable between Adam15-/- and WT, indicating less impact of ADAM15 loss in females post- MI. This study reports a novel function for ADAM15 in collagen cross-linking and optimal scar formation post-MI which may also apply to scar formation in other tissues.


Assuntos
Cicatriz , Infarto do Miocárdio , Proteínas ADAM/metabolismo , Animais , Cicatriz/genética , Cicatriz/patologia , Colágeno/metabolismo , Feminino , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Infarto do Miocárdio/genética , Infarto do Miocárdio/metabolismo , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Remodelação Ventricular/genética
13.
Sci Rep ; 11(1): 19022, 2021 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-34561473

RESUMO

Phosphatidylinositol glycan anchor biosynthesis class N (PIGN) has been linked to the suppression of chromosomal instability. The spindle assembly checkpoint complex is responsible for proper chromosome segregation during mitosis to prevent chromosomal instability. In this study, the novel role of PIGN as a regulator of the spindle assembly checkpoint was unveiled in leukemic patient cells and cell lines. Transient downregulation or ablation of PIGN resulted in impaired mitotic checkpoint activation due to the dysregulated expression of spindle assembly checkpoint-related proteins including MAD1, MAD2, BUBR1, and MPS1. Moreover, ectopic overexpression of PIGN restored the expression of MAD2. PIGN regulated the spindle assembly checkpoint by forming a complex with the spindle assembly checkpoint proteins MAD1, MAD2, and the mitotic kinase MPS1. Thus, PIGN could play a vital role in the spindle assembly checkpoint to suppress chromosomal instability associated with leukemic transformation and progression.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Transformação Celular Neoplásica/genética , Instabilidade Cromossômica/genética , Leucemia/patologia , Fosfotransferases/fisiologia , Fuso Acromático/metabolismo , Proteínas de Ciclo Celular/genética , Linhagem Celular , Progressão da Doença , Expressão Gênica , Células HL-60 , Humanos , Células K562 , Proteínas Mad2/genética , Proteínas Mad2/metabolismo , Fosfotransferases/genética , Fosfotransferases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Tirosina Quinases/genética , Proteínas Tirosina Quinases/metabolismo
14.
Cell ; 184(14): 3812-3828.e30, 2021 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-34214472

RESUMO

We study a patient with the human papilloma virus (HPV)-2-driven "tree-man" phenotype and two relatives with unusually severe HPV4-driven warts. The giant horns form an HPV-2-driven multifocal benign epithelial tumor overexpressing viral oncogenes in the epidermis basal layer. The patients are unexpectedly homozygous for a private CD28 variant. They have no detectable CD28 on their T cells, with the exception of a small contingent of revertant memory CD4+ T cells. T cell development is barely affected, and T cells respond to CD3 and CD2, but not CD28, costimulation. Although the patients do not display HPV-2- and HPV-4-reactive CD4+ T cells in vitro, they make antibodies specific for both viruses in vivo. CD28-deficient mice are susceptible to cutaneous infections with the mouse papillomavirus MmuPV1. The control of HPV-2 and HPV-4 in keratinocytes is dependent on the T cell CD28 co-activation pathway. Surprisingly, human CD28-dependent T cell responses are largely redundant for protective immunity.


Assuntos
Antígenos CD28/deficiência , Padrões de Herança/genética , Papillomaviridae/fisiologia , Pele/virologia , Linfócitos T/imunologia , Adulto , Sequência de Aminoácidos , Animais , Sequência de Bases , Antígenos CD28/genética , Antígenos CD28/metabolismo , Linfócitos T CD4-Positivos/imunologia , Criança , Endopeptidases/metabolismo , Feminino , Genes Recessivos , Células HEK293 , Homozigoto , Humanos , Imunidade Humoral , Memória Imunológica , Células Jurkat , Queratinócitos/patologia , Masculino , Camundongos Endogâmicos C57BL , Oncogenes , Papiloma/patologia , Papiloma/virologia , Linhagem , Sinais Direcionadores de Proteínas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
15.
Front Neurosci ; 15: 596976, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34149342

RESUMO

The blood-brain barrier (BBB) hinders the distribution of therapeutics intended for treatment of diseases of the brain. Our previous studies demonstrated that that a soluble form of melanotransferrin (MTf; Uniprot P08582; also known as p97, MFI2, and CD228), a mammalian iron-transport protein, is an effective carrier for delivery of drug conjugates across the BBB into the brain and was the first BBB targeting delivery system to demonstrate therapeutic efficacy within the brain. Here, we performed a screen to identify peptides from MTf capable of traversing the BBB. We identified a highly conserved 12-amino acid peptide, termed MTfp, that retains the ability to cross the intact BBB intact, distributes throughout the parenchyma, and enter endosomes and lysosomes within neurons, astrocytes and microglia in the brain. This peptide may provide a platform for the transport of therapeutics to the CNS, and thereby offers new avenues for potential treatments of neuropathologies that are currently refractory to existing therapies.

17.
Front Mol Biosci ; 8: 611367, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33869275

RESUMO

The blood-brain barrier (BBB) hinders the distribution of therapeutics intended for treatment of neuroinflammation (NI) of the central nervous system. A twelve-amino acid peptide that transcytoses the BBB, termed MTfp, was chemically conjugated to siRNA to create a novel peptide-oligonucleotide conjugate (POC), directed to downregulate NOX4, a gene thought responsible for oxidative stress in ischemic stroke. The MTfp-NOX4 POC has the ability to cross the intact BBB and knockdown NOX4 expression in the brain. Following induction of ischemic stroke, animals pretreated with the POC exhibited significantly smaller infarcts; accompanied by increased protection against neurological deterioration and improved recovery. The data demonstrates that the MTfp can act as a nanomule to facilitate BBB transcytosis of siRNAs; where the NOX-4 specific siRNA moiety can elicit effective therapeutic knockdown of a gene responsible for oxidative stress in the central nervous system. This study is the first to conclusively demonstrate both siRNA-carrier delivery and therapeutic efficacy in any CNS disease model where the BBB remains intact and thus offers new avenues for potential treatments of oxidative stress underlying neuroinflammation in a variety of neuropathologies that are currently refractory to existing therapies.

18.
Int J Nanomedicine ; 16: 2297-2309, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33776434

RESUMO

PURPOSE: Accurate tumor identification and staging can be difficult. Aptamer-targeted indocyanine green (ICG)-nanoparticles can enhance near-infrared fluorescent imaging of pancreatic and prostate tumors and could improve early cancer detection. This project explored whether calcium-phosphosilicate nanoparticles, also known as NanoJackets (NJs), that were bioconjugated with a tumor-specific targeting DNA aptamer could improve the non-invasive detection of pancreatic and prostate tumors. METHODS: Using in vivo near-infrared optical imaging and ex vivo fluorescence analysis, DNA aptamer-targeted ICG-loaded NJs were compared to untargeted NJs for detection of tumors. RESULTS: Nanoparticles were bioconjugated with the DNA aptamer AP1153, which binds to the CCK-B receptor (CCKBR). Aptamer bioconjugated NJs were not significantly increased in size compared with unconjugated nanoparticles. AP1153-ICG-NJ accumulation in orthotopic pancreatic tumors peaked at 18 h post-injection and the ICG signal was cleared by 36 h with no evidence on uptake by non-tumor tissues. Ex vivo tumor imaging confirmed the aptamer-targeted NJs accumulated to higher levels than untargeted NJs, were not taken up by normal pancreas, exited from the tumor vasculature, and were well-dispersed throughout pancreatic and prostate tumors despite extensive fibrosis. Specificity for AP1153-NJ binding to the CCK-B receptor on pancreatic tumor cells was confirmed by pre-treating tumor-bearing mice with the CCK receptor antagonist proglumide. Proglumide pre-treatment reduced the in vivo tumoral accumulation of AP1153-NJs to levels comparable to that of untargeted NJs. CONCLUSION: Through specific interactions with CCK-B receptors, tumor-targeted nanoparticles containing either ICG or rhodamine WT were well distributed throughout the matrix of both pancreatic and prostate tumors. Tumor-targeted NJs carrying various imaging agents can enhance tumor detection.


Assuntos
Aptâmeros de Nucleotídeos/química , Diagnóstico por Imagem , Nanopartículas/química , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias da Próstata/diagnóstico por imagem , Silicatos/química , Animais , Cálcio , Linhagem Celular Tumoral , Corantes , Fluorescência , Humanos , Verde de Indocianina/química , Raios Infravermelhos , Masculino , Camundongos , Neovascularização Patológica/diagnóstico por imagem , Neoplasias Pancreáticas/irrigação sanguínea , Neoplasias da Próstata/irrigação sanguínea , Receptores da Colecistocinina/metabolismo , Rodaminas/química , Microambiente Tumoral
19.
Environ Sci Pollut Res Int ; 28(16): 20247-20260, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33410068

RESUMO

The sulfur-doped graphene oxide (sGO)-integrated Ag3PO4 composite displayed very high catalytic activity toward prominent water pollutants like textile dyes and fungicide under sunlight. The optimum amount of sGO doping was found as 5% for degradation. The novel composite degraded 99% of methylene blue (MB) in only 5 min of sunlight exposure, which is 16 and 8 times faster than Ag3PO4 and 5% GO-Ag3PO4. High mineralization was observed for MB with a total organic carbon (TOC) removal of 98% in 30 min. The composite mineralized rhodamine B, methyl orange, and acid red 18 dyes with a TOC removal above 95%. Moreover, a toxic dithiocarbamate fungicide thiram was degraded in 1 h with a TOC removal of 82% leaving less toxic thiourea. The formation of sGO-Ag3PO4 n-n heterojunction increases charge transport and photocatalytic activity of the composite to incredible extent along with hollow morphology and in situ formed Ag nanoparticles (AgNPs).


Assuntos
Poluentes Ambientais , Fungicidas Industriais , Nanopartículas Metálicas , Nanocompostos , Poluentes da Água , Catálise , Corantes , Grafite , Fosfatos , Prata , Compostos de Prata , Enxofre , Água
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